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| Paul Stowe... |
 Posted: Fri Nov 06, 2009 1:12 pm |
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On Nov 6, 2:45 pm, BURT <macromi... at (no spam) yahoo.com> wrote:
[quote]Physics is questionable as a science?
Has someone gone into denial?
Mitch Raemsch
[/quote]
I disagree, physics is not a questionable science, some of the current
practices/practitioners are questionable. You will find that most
thing I claim I can back up with quantifiable references and/or data. |
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| PD... |
| Posted: Fri Nov 06, 2009 1:19 pm |
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On Nov 6, 4:27 pm, Paul Stowe <theaether... at (no spam) gmail.com> wrote:
[quote]On Nov 6, 2:17 pm, PD <thedraperfam... at (no spam) gmail.com> wrote:
On Nov 6, 4:00 pm, PaulStowe<theaether... at (no spam) gmail.com> wrote:
On Nov 6, 1:49 pm, PD <thedraperfam... at (no spam) gmail.com> wrote:
On Nov 6, 3:39 pm, PaulStowe<theaether... at (no spam) gmail.com> wrote:
On Nov 6, 12:50 pm, PD <thedraperfam... at (no spam) gmail.com> wrote:
On Nov 6, 2:03 pm, Vern <vthod... at (no spam) gmail.com> wrote:
Ether theory(ies) model every aspect of nature in this domain as well
as providing models in other domains and are not ruled out by
experimental or observational data.
Except for that slowing business you just mentioned. Ruled out by
experimental data.
You MAY want to take that into consideration.
You see, you just did something useful with the ether model -- you
came up with a prediction of a measurable phenomenon that clearly
distinguishes it from relativity. That is an admirable accomplishment,
because it sets the stage for unambiguously determining which of the
two is actually right. As it turns out, though (and this is the way it
should be), nature has made its unbiased evaluation -- and the ether
model's prediction tanked.
PD
Show me some numbers... How much change in speed do you expect??? If
some particle is moving at 2.85E+08 m/sec and is experiencing 2E-05 m/
sec^2 deceleration in one kilometer it will see a 0.2 m/sec change.
That's ~7E-08% change. EVEN IF! you were looking for it I doubt you
could detect it. If you have another model to quantify deceleration,
by all means show us!
Where do YOU get 2E-5 m/s^2 deceleration?
Where do you get one from??? All I see is undefined denials...
Look back in this thread and the equation is given...
The one that was given was this:
A_d = (-fu/c)v
Where f = the aether's momentum flux (kg/m-sec^2) = 6.74E+00
u = the mass attenuation coefficient (m^2/kg) = 3.15E-06
c = the Root Mean Speed of the aether (m/sec) = 3.00E+08
v = the net speed of the mass in m/sec
It's interesting that this expression does not include the mass of the
object in the aether, which means that a bowling ball is decelerated
at the same rate as a helium balloon of the same volume, and at the
same rate as a proton.
It also predicts a sizable energy loss from stars to the surrounding
medium, so that 1/r^2 radiative scaling would not apply. This is
easily testable.
It also predicts a sizable delay between particles observed from
stellar sources, compared to the photon equivalents. We can measure
the speed of the particles upon their arrival at the observatory (with
a TOF or Cerenkov counter, eg.), use the relation above to integrate
what the source speed was, and then use that velocity profile to track
back the time of the release of the particles compared to that of the
light. This time would be much earlier than a similar traceback that
assumes the particles traveled at constant speed from the origin. If
the origin time is weeks before the origin of the light, would this
make you suspect that the relation has a problem?
What I don't see is anything quantitive from you... It was 'you' who
claimed Vern's process proved something, not him, so show us the
numbers & analysis to back that up.
[/quote]
Particle buckets are timed at fixed target machines (free flight
beamlines) to a precision of 12 ps. The FNAL beamline out to the first
MINOS station is about 2.5 km. The transit time of particles out to
that location from extraction is 8 usec. The transit time to the
second station is 2.4 msec. And that's a SHORT throw, compared to
stellar generators.
[quote]
Do you find it strange that a feather would decelerate at the same
rate as a uranium bowling ball? Where else is this property seen?
[/quote]
When something is receding from a large gravitational mass. Not when
one is traveling perpendicular to one, for example. |
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| John Kennaugh... |
| Posted: Sat Nov 07, 2009 5:01 am |
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PD wrote:
[quote]On Nov 5, 11:46 am, John Kennaugh <J... at (no spam) notworking.freeserve.co.uk
wrote:
PD wrote:
On Nov 5, 7:34 am, Vern <vthod... at (no spam) gmail.com> wrote:
On Nov 4, 5:53 pm, "Inertial" <relativ... at (no spam) rest.com> wrote:
"PD" <thedraperfam... at (no spam) gmail.com> wrote in message
snip
Please. Look up Minkowski space.
Also see the definition of what 'flat' means
http://www.answers.com/topic/flat-space
http://www.answers.com/topic/flat-space-time
Minkowski spacetime is a geometry that is flat.
In terms of a model for explaining known phenomena, space-time in the
absense of gravity would then only be posited to account for a speed
limit,
And the invariance of that limit with respect to inertial reference
frame, or if you like, independence on source speed.
right, and as a result, mass must increase as speeds approach
"c" and time slows down.
These are comic-book versions of what relativity says. The invariant
mass remains invariant. There was once a bridge concept called
"relativistic mass" which was the product of two terms in the
relativistic equation of momentum, so that the product could look
something like the classical equation of momentum. This bridge concept
is no longer really thought of as being useful, it being much more
straightforward to just recognize that the classical expression is
simply an approximation to the more correct one.
And the mechanism (how it's caused) for this
is still unknown.
There is no "mechanism" needed. Even in classical physics, the kinetic
energy of a single object can be zero and nonzero at the same time in
two different reference frames.
As I have previously pointed out that is a non sense argument. If two
objects fly through space and collide one may calculate the kinetic
energy involved in the collision but it is silly to attribute kinetic
energy to one or other of the objects. One may arbitrarily do so for
calculation but it is otherwise meaningless. Kinetic energy involves an
interaction of two (or more) objects and is dependent on their relative
speeds. It is therefore nonsensical to say that "the kinetic energy of a
single object can be zero and nonzero at the same time in two different
reference frames". The kinetic energy of a single object is a
meaningless concept (except for rotational kinetic energy which we are
not dealing with here).
Fascinating. And yet kinetic theory makes extensive use of the kinetic
energy of the individual elements in the medium.
Do you have any references from classical physics that support your
position on this?
[/quote]
Do you have any logical argument against my position?
[quote]
There is no "mechanism" of how the
kinetic energy suddenly appeared in one frame when it was zero in the
other.
If I am hit by a bullet one may arbitrarily think of the bullet as
having the kinetic energy but it is wrong to do so. It is no more and no
less sensible to suggest that it is I who bring the energy involved in
the collision. If I *change my speed* w.r.t the gun and am hit by an
identical bullet then the energy of the interaction will change and the
process/mechanism which caused that change in the kinetic energy of
interaction is that which changed my speed - I put my foot on the
accelerator ............
If someone else travelling at a different speed is hit by a bullet then
that is an entirely different interaction between him and the bullet and
again it is meaningless to talk about whether it is him or the bullet
which has the kinetic energy.
The problem is that people like you are so used to talking about frames
of reference they start to become real to you and an excuse for all
sorts of twisted thinking. As a FoR does not physically exist, then
anything sensible in physics should be capable of explanation without
using the phrase. You should try it.
--
John Kennaugh
[/quote]
--
John Kennaugh |
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| PD... |
| Posted: Sat Nov 07, 2009 6:54 am |
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On Nov 7, 7:00 am, John Kennaugh <J... at (no spam) notworking.freeserve.co.uk>
wrote:
[quote]PD wrote:
On Nov 1, 5:39 am, John Kennaugh <J... at (no spam) notworking.freeserve.co.uk
wrote:
Paul Stowe wrote:
On Oct 31, 7:08 am, PD <thedraperfam... at (no spam) gmail.com> wrote:
On Oct 31, 5:49 am, John Kennaugh <J... at (no spam) notworking.freeserve.co.uk
snip for brevity.
John, PD may understand (I don't think he's that stupid) but, is he
capable of acknowledgement, that's the real question.
I got a strong indication at one point that PD teaches/lectures in
physics. When asked he refused to answer but I think I hit the nail on
the head.
Why do you think it matters?
It is always nice if ones deductions are confirmed.
The first clue is when you and I discussed history where you insisted in
wrapping it up in all sorts of flannel. I persisted and eventually won
the day with my argument and in the end you changed tack and stated "IT
DOESN'T MATTER where the second postulate came from". I might say that
you earned my respect in that faced with a strong enough argument you
did give ground. There are few around here who will do that.
Such a person's role is to present (sell) physics to students
not to question it.
I'm sorry, but here I have to object. You have NO idea, obviously,
what a professor's role is in teaching students.
Before you can teach them any of that you have first to get them to
accept certain things which they may be reluctant to accept. SR being
the most obvious. You cannot go honestly through the history and show
that it follows logically because it doesn't. It is what you would call
counter-intuitive (I might describe it in more earthy language).
You really have no choice in that you have to persuade your students to
accept relativity because unless they do you cannot move on. In fact if
you cannot persuade a student, your only option is to suggest he takes
another course of study.
[/quote]
This is flat wrong. Let me give you a simple example to illustrate.
In FIRST semester physics, students are taught a number of things and
why we have come to believe that they are correct.
For example, that velocities transform from one inertial reference
frame by simple vector addition with the relative velocity between
frames.
For example, that momentum is mv, and that kinetic energy is mv^2/2.
For example, that the mass of a system is the sum of the masses of the
objects in that system.
For example, that the universal law of gravitation that seems to work
for everything is given by F = GMm/r^2.
Now, it would be foolish of you to say that we expect students to
*accept* these statements because they have to, otherwise they cannot
go on. We do not expect students to *accept* these statements because
we know FULL WELL that by the end of the second semester, we will have
told those same students that those statements are wrong, and how we
know they are wrong.
Teaching science is not at all about what statements to accept. It is
teaching them how the process of induction of physical laws works: why
we believe they are right, how they are tested, how they are applied,
and then what to do when we find cases where the application does not
seem to work so well.
It is clear that YOU were led to believe that the statements presented
in your classes were just to be accepted. This is unfortunate, and may
be the result of a poor teacher or you being a poor student or a
combination of both. In any event, if this is what you were led to
believe, then you missed the point of your education in physics almost
completely.
[quote]
You *believe* that relativity is correct and that the modern physics
built upon that foundation is both sound and fascinating.
[/quote]
That is actually not quite what I believe. I believe that relativity
has been extremely useful in its own right and in being one of the
struts used to build other theories (like quantum field theories) that
have also turned out to be extremely useful. I also believe that there
does not seem to be credible or reproducible evidence that indicates
that relativity is wrong -- SO FAR. This does not mean that I believe
relativity is inviolate -- just that I have no reason yet to doubt it.
[quote]It is in the
interests of your students that they be persuaded and that justifies the
tactics you employ. Once over the initial difficulty you are confident
that when the student sees what has been built on those less than
satisfactory foundations he will realise that where they originated
doesn't matter.
[/quote]
Yes, this is correct, because the historical thought process IS NOT
CENTRAL to the truth of the propositions. That does not hinge on
whether the right answer was inevitable from the information give, or
whether it was landed on by good instinct and practically nothing
else, or even whether the correct answer was stumbled on through a
*mistake*. The reason is that the truth is not determined by the
*deduction* but by the tests of its predictions in experiment. In
science, the deductive methodology is *completely* secondary to the
experimental verification.
[quote]
From your point of view it is legitimate to use spin and carefully
chosen ways of presenting it. Hence I spotted you as an educator because
you have been treating me as a troublesome student.
[/quote]
Not troublesome, but not very promising either, because you have
missed the point almost completely about how science works. This is
not a personal slam against your intellect. It is simply pointing out
that you have missed something really important.
[quote]Applying all the
tricks and techniques you have developed over the years to get a student
on board (for his own good) even resorting to ridicule suggesting that
my problem was with Classical mechanics - which was a tad dishonest you
must admit. Hence my comment that you are intelligent enough to know
that you are being dishonest.
One problem is that at the end of the course you do not go back and put
it right. Students leave with a totally false sense of the origins of SR
and continue to believe the myth throughout their career.
[/quote]
I'm sorry that you were left with some mistaken impressions in your
education and that you feel misled as a result.
I would suggest that students only come to a full appreciation of the
real development of concepts and how science works after four or six
years of concentrated immersion in it. It is not pedagogically useful
to dot the i's and cross the t's in the early courses, and it
CERTAINLY is not in the interests of the authors of popularizations to
do so. Those who take a special interest in crossed ts and dotted i's
are invited to further study.
[quote]
People compiling text books do so to make money. To do that they require
that educators choose their book as the 'course book' and for that to
happen they have to help the educator side step the difficult issues.
[/quote]
No, they do not. They are adopted if they do a good job presenting the
difficult issues. I don't know what textbook you used, but most of
them that I've used are careful to point out those places where we
don't yet have a full understanding. However, they DO present things
that they will later retract, or that they know will have to be looped
back upon in later courses.
[quote]You want to give the students the impression that there was no
alternative to relativity so the chosen book will not mention Ritz. If
it did you might get bogged down trying to explain why his theory was
rejected and that would be difficult - so best not mention him. If the
subject was raised you might have to distort history (as you have tried
with me) mentioning experiments which occurred long after the event,
without making that clear.
[/quote]
There are ALWAYS choices made in presenting materials. There are
*hundreds* of alternative models that are available to choose from in
any given chapter of any given book. The fact that your favorite is
not brought up in the book you chose is not suppression, it is page-
count management.
[quote]
It is also a good idea for a book to play down the role of Lorentz, even
going as far as leaving the false impression that his length contraction
was a rather silly ad-hoc assumption when it wasn't. Lorentz was a first
rate physicist
[/quote]
Yes, he was, and good physics books make a point of saying so.
[quote]but you have to sell Einstein - who wasn't (personal
opinion) and as far as SR is concerned came up with nothing which
Lorentz had not already come up with. You will perpetuate the myth that
Einstein came up with a marvellous theory which showed the aether to be
unnecessary. This isn't true, Physics quite arbitrarily changed its own
definition as to what a theory was
[/quote]
No, sir. You are mistaken. However, it DID question itself as to what
the essential aspects of a physical theory must entail.
For example, you are under the impression that at one time a theory
had to be time-ordered and deterministic to even be considered a
theory at all. And that if anything came along that didn't feature
time-ordered determinism and it was called a theory, then it was
redefining what "physical theory" even meant. That is wrong.
[quote]and deemed physical interpretation
unnecessary - thus the aether, as the physical explanation previously
underpinning physical theory became redundant. It did not result from
anything Einstein did (he supported the aether concept) but from the
desire by others to accept his theory despite him not having come up
with a theoretical structure to replace the one of Lorentz which he had
objected to.
The book will typically place great emphasis on Maxwell's *equations* to
avoid mention of the key role of the aether. The fact is that history
makes no sense without the aether, without something you have to teach
is a silly idea. A text book can safely claim that Maxwell's equations
imply whatever it wants - a first year student won't understand them so
cannot challenge it.
[/quote]
That is also mistaken. A first year student is given the opportunity
to challenge it, but may be promised that this will be addressed in
SECOND year.
If you are so impatient that you need it addressed in the first year,
then you have the opportunity for side study.
[quote]
When my interest in relativity was first kindled I realised that the
book I had
[/quote]
Which was what? And why were you using just one book? And who was your
guide through that book?
[quote]was using semantic slight of hand - "the MMX has showed that
an observer's speed did not affect the speed of light" (not actually
untrue IN CONTEXT of the MMX although it would be more accurate to talk
of the speed of the observer's apparatus). By using identical wording in
the relativity chapter it tried to leave the impression that the second
postulate follows directly from the MMX
[/quote]
You're right, that is a MISTAKEN impression. You got a mistaken
impression from the book you were reading. So? Who's to blame for
that?
[quote]i.e. that it had been
experimentally proven.
[/quote]
The second postulate was certainly not proven at the time it was
posited. However, there is a WEALTH of information that has been
collected since that time.
[quote]It appears that some people around here still
believe that and they are in good company. Stephen Hawking has
apparently based his life's work on that belief. I found the same
technique in several books - authors look to see how other books get
around a difficulty.
I realised the problem presented by Doppler shift. By definition Doppler
frequency shift is the result in a change of speed relative to the wave.
[/quote]
No sir. That is NOT the definition of Doppler shift. If you were led
to that impression, then again you were misled.
[quote]Text books tend to avoid it for good reason. I looked in various text
books - they side stepped the issue talking about train whistles and
"similar principles apply". I only found one book which attempted to
deal with it differently and when I had got my head around the over
complicated description, it was attempting to draw a distinction between
speed and rate of change of distance!
I eventually realised that text books only ever describe light leaving a
source as viewed from the source's FoR. This was what was inhibiting my
understanding. In the observer's FoR the source is an object like any
other object and SR requires that light travels at c w.r.t the FoR not c
w.r.t every object moving in the FoR and it is therefore not c w.r.t a
source moving in the observers FoR. "Oh yes it is" I was told. It
eventually became clear that physics has hijacked the English language
so that it was almost impossible to express this idea. I was told that
no matter what lengths I went to, to explain that I was describing it
from the PoV of the observer's FoR that as soon as I wrote "w.r.t. the
source" it was taken to mean that I had changed my FoR to that of the
source. I have had to learn my own semantic work-around. In an
observer's FoR light can have a speed of separation from the source
between 0 and 2c as is the case of the speed of separation or closure of
any other object in the observer's FoR.
[/quote]
It appears you are severely lacking a competent guide through the
material, and somehow others are to blame for that.
[quote]
In Sound there are two different physical mechanisms producing Doppler.
Change in the speed of the source (freq changes because the wave
separates from the source at a slower speed ahead of the source and
faster behind the source so wavelengths are compressed forward and
stretched behind it), and observer moving (freq change because he is
passing the wavecrests at a different speed).
There is only one mathematical basis for Doppler in SR and that is a
change in the speed of separation from the source generating different
wavelengths.
[/quote]
No, this isn't right, either.
[quote]This has to act for both a change of speed of the source
and a change of speed of the observer thus avoiding the need for the
speed of the wave relative to the observer ever changing as one might
expect if the observer changes his speed. There is a problem with that.
If I change my speed the frequency changes instantly. Clearly It is not
my change in speed w.r.t the light source - which may be 1 ly away and
may have ceased to exist, nor is it my change in absolute speed - which
is a concept denied by SR. I have changed my relationship with the light
locally and the only thing which has changed is my speed.
You can wrap that up in any degree of mathematical sophistication you
like it doesn't alter the fact that it is physical nonsense. It also
exposes the weakness of accepting a mathematical model as a "physics
theory". It isn't. Physical interpretation is an essential part of
physics whether you like it or not. A mathematical model does not care
a fig whether it is describing something physically impossible. So if my
decision to change my speed requires that light started separating from
the source at a different speed a year previous in anticipation of that
decision - there is NOTHING in a mathematical model to prevent that
neither is there anything inhibiting the existence of many separate
realities simultaneously and my moving from one to another.
As I say above. Having used all sorts of spin, reflected in text books
students can go through their career without it ever being corrected.
Tom Roberts for example is confused.
Me : The wavelength is a function of the speed of separation of the
light at the source 1 ly away.
Tom: This is grotesquely wrong.
Me It is absolutely right.
Tom: Nonsense. The "speed of separation of the light at the source" is
c, a single value.
Me: Only in the FoR of the source.
Tom: If wavelength were indeed a function of the speed of separation
from the source, then all light would necessarily have a single
wavelength -- it doesn't.
Your basic error is saying "the wavelength", implicitly thinking it is a
property of the light; it isn't. It requires an instrument to measure
the wavelength of light, and the value obtained depends on properties of
the instrument (e.g. its velocity wrt the source of the light).
Me: How can the RELATIVE velocity of the source affect my ruler or the
clock of my frequency counter?
Tom did not respond despite having two further opportunities to do so.
Although text books go to some length to avoid saying so it is inherent
that in the observer's FoR light separates from the source at whatever
speed is necessary for it to be c in the observer's FoR and that SR
requires that that has an affect on what you physically measure by way
of frequency.
I do not accept that a particular generation of "physicists" has a right
to say that "Physics is whatever we say it is". The dumbing-down of
physics is a highly regrettable expedient but you as an educator CANNOT
question that wisdom if you want to retain your post, anymore than
someone teaching theology can question the existence of god.
[/quote]
Of COURSE someone teaching theology can question the existence of God.
It is the questioning, and how those questions get answered, that is
the very basis of doing the study!
[quote]
The professor's job
is to make excellent investigators of nature, highly trained in the
best methodology obtained for that purpose -- the scientific method.
It is the full expectation that students who go on to be outstanding
investigators will make a singular mark, and you'll note that awards
and honors are given to those investigators that *break* with the
status quo. You only need look at the list of Nobel laureates and
their work to understand that. Positions of investigatory freedom and
support for such work, however, comes at the cost of demonstrating
competence with the methodology. This includes understanding how to
probe the validity of ANY idea (including time-ordered determinism)
with a well-crafted experimental test, as well as being comfortable
with the mathematical toolbox that is so useful in shorthanding
underlying concepts without excess baggage.
It is NOT the job of the professor to drum into student's head this
assertion or that assertion. It IS the job of the professor to get
students to see HOW we know those things we think we do know, as well
as those things we DON'T know and how we might go about finding the
answers to them. It is the poor student that just accepts things
without asking how we know, and it is also the poor student who just
reject things without entertaining the same.
[/quote]
You see?
[quote]
Many of his posts seem to be well honed techniques
of presentation which carefully avoid problems. Others are put-downs
intended for the more difficult student and intended to make a student
look small - as if he has made a really stupid remark - when in fact he
is thinking for himself. If that be the case then acknowledgement > >> failure i.e. if he is forced to admit to his students that the subject
he is teaching is fundamentally flawed he can't do his job.
Forgive me if this sounds like sour grapes, uttered by someone who has
felt inadequate in the study of physics and finds it confusing.
I never suggested that you felt inadequate or that you find it
confusing. I credit you with believing in what you are doing. That it is
in the best interests of your students.ou
Might
I suggest you try again with an education in the subject, being more
selective with both your materials and your teachers?
Perhaps some other educator would succeed where you have failed  )
I am certainly not going to be convinced by anyone trying to convince me
by distorting history, applying spin, and bullying tactics and I am now
an expert at spotting those techniques.
[/quote]
I am certainly not attempting to educate you on a newsgroup. A
newsgroup is NOT a place to get an education in physics.
If you want to get an education in physics, I can make some
suggestions about a more effective venue.
[quote]
I don't object you or anyone thinking for yourself. However, if you've
not availed yourself of the information that is pertinent to your
ponderings,
What information would that be.
then you have some work to do and that burden does lie on
you -- unless you've *paid* for the service of being guided through
it.
If it your belief that you are entitled to an education that
satisfies you on Usenet, then I'm afraid I have bad news.
You can find things on the Internet which no educator would want in his
text book - not because they are not true but because they would make
his life difficult.
[/quote]
This is bullshit. On the internet there is no quality control and
someone with a misaligned bullshit meter will get led astray EVERY
TIME.
[quote]
Perhaps I should try a historian to get a balanced view. Perhaps I
should study Sir Edmund Whittaker's The History of Theories of Aether
and Electricity - trouble is it runs to several volumes. Apparently
there is a chapter on relativity, entitled, "The Relativity Theory of
Poincare and Lorentz." Einstein is mentioned for the first time in a
paragraph on the thirteenth page.
"(1905) Einstein published a paper which set forth the relativity
theory of Poincare and Lorentz with some amplification, and which
attracted much attention. He asserted as a fundamental principle the
constancy of the velocity of light, i.e., that the velocity of light in
a vacuum is the same in all systems of reference which are moving
relatively to each other, an assertion which at the time was widely
accepted. In this paper Einstein gave modifications which must now be
introduced into the formulae for aberration and for the Doppler effect."
--
John Kennaugh "... what at its beginnings is recognised as a speculation, with
greater or less plausibility, develops with time into a compulsory dogma, which
whosoever disbelieves thereby brands himself as an ignorant fool." Dingle[/quote] |
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| Paul Stowe... |
| Posted: Sat Nov 07, 2009 6:56 am |
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On Nov 6, 3:19 pm, PD <thedraperfam... at (no spam) gmail.com> wrote:
[quote]On Nov 6, 4:27 pm, PaulStowe<theaether... at (no spam) gmail.com> wrote:
On Nov 6, 2:03 pm, Vern <vthod... at (no spam) gmail.com> wrote:
Ether theory(ies) model every aspect of nature in this domain as well
as providing models in other domains and are not ruled out by
experimental or observational data.
Except for that slowing business you just mentioned. Ruled out by
experimental data.
You MAY want to take that into consideration.
You see, you just did something useful with the ether model -- you
came up with a prediction of a measurable phenomenon that clearly
distinguishes it from relativity. That is an admirable accomplishment,
because it sets the stage for unambiguously determining which of the
two is actually right. As it turns out, though (and this is the way it
should be), nature has made its unbiased evaluation -- and the ether
model's prediction tanked.
PD
Show me some numbers... How much change in speed do you expect??? If
some particle is moving at 2.85E+08 m/sec and is experiencing 2E-05 m/
sec^2 deceleration in one kilometer it will see a 0.2 m/sec change.
That's ~7E-08% change. EVEN IF! you were looking for it I doubt you
could detect it. If you have another model to quantify deceleration,
by all means show us!
Where do YOU get 2E-5 m/s^2 deceleration?
Where do you get one from??? All I see is undefined denials...
Look back in this thread and the equation is given...
The one that was given was this:
A_d = (-fu/c)v
Where f = the aether's momentum flux (kg/m-sec^2) = 6.74E+00
u = the mass attenuation coefficient (m^2/kg) = 3.15E-06
c = the Root Mean Speed of the aether (m/sec) = 3.00E+08
v = the net speed of the mass in m/sec
It's interesting that this expression does not include the mass of the
object in the aether, which means that a bowling ball is decelerated
at the same rate as a helium balloon of the same volume, and at the
same rate as a proton.
It also predicts a sizable energy loss from stars to the surrounding
medium, so that 1/r^2 radiative scaling would not apply. This is
easily testable.
It also predicts a sizable delay between particles observed from
stellar sources, compared to the photon equivalents. We can measure
the speed of the particles upon their arrival at the observatory (with
a TOF or Cerenkov counter, eg.), use the relation above to integrate
what the source speed was, and then use that velocity profile to track
back the time of the release of the particles compared to that of the
light. This time would be much earlier than a similar traceback that
assumes the particles traveled at constant speed from the origin. If
the origin time is weeks before the origin of the light, would this
make you suspect that the relation has a problem?
What I don't see is anything quantitive from you... It was 'you' who
claimed Vern's process proved something, not him, so show us the
numbers & analysis to back that up.
Particle buckets are timed at fixed target machines (free flight
beamlines) to a precision of 12 ps. The FNAL beamline out to the first
MINOS station is about 2.5 km. The transit time of particles out to
that location from extraction is 8 usec.
[/quote]
At 2.5 km with speed c it's 8.34E-06 usec. If the precision is +/- 12
psec, that's 4 orders of magnitude too large to see the predicted
change in the arrival time due to aether deceleration and that's EVEN
IF! you could separate it from an imparted energy vavriance.
[quote]The transit time to the
second station is 2.4 msec. And that's a SHORT throw, compared to
stellar generators.
[/quote]
If m is mil, then at c that's 72 km. At that distance the delay in
arrival would be ~24 psec, a change in 1 part in 10^8. Again, there
is no way you can separate this from imparted energy to the
particle... Thus your 'off the cuff' claim,
"... As it turns out, though (and this is the way it
should be), nature has made its unbiased evaluation
-- and the ether model's prediction tanked."
is false, and in fact at (no spam) 12.2 kps the predicted deceleration is 8.6E-10
m/sec^2 and the Pioneer spacecraft moving at ~12.2 kps when compared
to a measured deceleration of 8.7E-10 +/- 1.33 m/sec^2 matches the
long term (20 yrs) observation. Thus it is just the opposite of your
bluster, it is the aether model that clearly is shown by observation
to be the correct predictor. There is more of course, that same model
says the big G is the product of two physical terms, aether flux (f)
and a mass attenuation coefficient (u) such that,
G = fu^2 (6.74)(3.147E-06) -> 6.673E-11 m^3/kg-sec^2
and has NO! expectation of being constant since in a medium the
momentum flux is a function of density, and, as we all know, density
can vary with position. As we also know, wave speed c also varies
with density. Thus in that case, IN the EFEs G and c cannot be taken
as constants.
[quote]Do you find it strange that a feather would decelerate at the same
rate as a uranium bowling ball? Where else is this property seen?
When something is receding from a large gravitational mass. Not when
one is traveling perpendicular to one, for example.
[/quote]
This just indicates your lack of understanding the model. In the weak
limit the aether 'field' acts equally upon all sub-atomic constituents
uniformly, thus bulk mass plays no role in such a process. |
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| John Kennaugh... |
| Posted: Sat Nov 07, 2009 8:00 am |
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Guest
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PD wrote:
[quote]On Nov 1, 5:39 am, John Kennaugh <J... at (no spam) notworking.freeserve.co.uk
wrote:
Paul Stowe wrote:
On Oct 31, 7:08 am, PD <thedraperfam... at (no spam) gmail.com> wrote:
On Oct 31, 5:49 am, John Kennaugh <J... at (no spam) notworking.freeserve.co.uk
[/quote]
snip for brevity.
[quote]
John, PD may understand (I don't think he's that stupid) but, is he
capable of acknowledgement, that's the real question.
I got a strong indication at one point that PD teaches/lectures in
physics. When asked he refused to answer but I think I hit the nail on
the head.
Why do you think it matters?
[/quote]
It is always nice if ones deductions are confirmed.
The first clue is when you and I discussed history where you insisted in
wrapping it up in all sorts of flannel. I persisted and eventually won
the day with my argument and in the end you changed tack and stated "IT
DOESN'T MATTER where the second postulate came from". I might say that
you earned my respect in that faced with a strong enough argument you
did give ground. There are few around here who will do that.
[quote]Such a person's role is to present (sell) physics to students
not to question it.
I'm sorry, but here I have to object. You have NO idea, obviously,
what a professor's role is in teaching students.
[/quote]
Before you can teach them any of that you have first to get them to
accept certain things which they may be reluctant to accept. SR being
the most obvious. You cannot go honestly through the history and show
that it follows logically because it doesn't. It is what you would call
counter-intuitive (I might describe it in more earthy language).
You really have no choice in that you have to persuade your students to
accept relativity because unless they do you cannot move on. In fact if
you cannot persuade a student, your only option is to suggest he takes
another course of study.
You *believe* that relativity is correct and that the modern physics
built upon that foundation is both sound and fascinating. It is in the
interests of your students that they be persuaded and that justifies the
tactics you employ. Once over the initial difficulty you are confident
that when the student sees what has been built on those less than
satisfactory foundations he will realise that where they originated
doesn't matter.
From your point of view it is legitimate to use spin and carefully
chosen ways of presenting it. Hence I spotted you as an educator because
you have been treating me as a troublesome student. Applying all the
tricks and techniques you have developed over the years to get a student
on board (for his own good) even resorting to ridicule suggesting that
my problem was with Classical mechanics - which was a tad dishonest you
must admit. Hence my comment that you are intelligent enough to know
that you are being dishonest.
One problem is that at the end of the course you do not go back and put
it right. Students leave with a totally false sense of the origins of SR
and continue to believe the myth throughout their career.
People compiling text books do so to make money. To do that they require
that educators choose their book as the 'course book' and for that to
happen they have to help the educator side step the difficult issues.
You want to give the students the impression that there was no
alternative to relativity so the chosen book will not mention Ritz. If
it did you might get bogged down trying to explain why his theory was
rejected and that would be difficult - so best not mention him. If the
subject was raised you might have to distort history (as you have tried
with me) mentioning experiments which occurred long after the event,
without making that clear.
It is also a good idea for a book to play down the role of Lorentz, even
going as far as leaving the false impression that his length contraction
was a rather silly ad-hoc assumption when it wasn't. Lorentz was a first
rate physicist but you have to sell Einstein - who wasn't (personal
opinion) and as far as SR is concerned came up with nothing which
Lorentz had not already come up with. You will perpetuate the myth that
Einstein came up with a marvellous theory which showed the aether to be
unnecessary. This isn't true, Physics quite arbitrarily changed its own
definition as to what a theory was and deemed physical interpretation
unnecessary - thus the aether, as the physical explanation previously
underpinning physical theory became redundant. It did not result from
anything Einstein did (he supported the aether concept) but from the
desire by others to accept his theory despite him not having come up
with a theoretical structure to replace the one of Lorentz which he had
objected to.
The book will typically place great emphasis on Maxwell's *equations* to
avoid mention of the key role of the aether. The fact is that history
makes no sense without the aether, without something you have to teach
is a silly idea. A text book can safely claim that Maxwell's equations
imply whatever it wants - a first year student won't understand them so
cannot challenge it.
When my interest in relativity was first kindled I realised that the
book I had was using semantic slight of hand - "the MMX has showed that
an observer's speed did not affect the speed of light" (not actually
untrue IN CONTEXT of the MMX although it would be more accurate to talk
of the speed of the observer's apparatus). By using identical wording in
the relativity chapter it tried to leave the impression that the second
postulate follows directly from the MMX i.e. that it had been
experimentally proven. It appears that some people around here still
believe that and they are in good company. Stephen Hawking has
apparently based his life's work on that belief. I found the same
technique in several books - authors look to see how other books get
around a difficulty.
I realised the problem presented by Doppler shift. By definition Doppler
frequency shift is the result in a change of speed relative to the wave.
Text books tend to avoid it for good reason. I looked in various text
books - they side stepped the issue talking about train whistles and
"similar principles apply". I only found one book which attempted to
deal with it differently and when I had got my head around the over
complicated description, it was attempting to draw a distinction between
speed and rate of change of distance!
I eventually realised that text books only ever describe light leaving a
source as viewed from the source's FoR. This was what was inhibiting my
understanding. In the observer's FoR the source is an object like any
other object and SR requires that light travels at c w.r.t the FoR not c
w.r.t every object moving in the FoR and it is therefore not c w.r.t a
source moving in the observers FoR. "Oh yes it is" I was told. It
eventually became clear that physics has hijacked the English language
so that it was almost impossible to express this idea. I was told that
no matter what lengths I went to, to explain that I was describing it
from the PoV of the observer's FoR that as soon as I wrote "w.r.t. the
source" it was taken to mean that I had changed my FoR to that of the
source. I have had to learn my own semantic work-around. In an
observer's FoR light can have a speed of separation from the source
between 0 and 2c as is the case of the speed of separation or closure of
any other object in the observer's FoR.
In Sound there are two different physical mechanisms producing Doppler.
Change in the speed of the source (freq changes because the wave
separates from the source at a slower speed ahead of the source and
faster behind the source so wavelengths are compressed forward and
stretched behind it), and observer moving (freq change because he is
passing the wavecrests at a different speed).
There is only one mathematical basis for Doppler in SR and that is a
change in the speed of separation from the source generating different
wavelengths. This has to act for both a change of speed of the source
and a change of speed of the observer thus avoiding the need for the
speed of the wave relative to the observer ever changing as one might
expect if the observer changes his speed. There is a problem with that.
If I change my speed the frequency changes instantly. Clearly It is not
my change in speed w.r.t the light source - which may be 1 ly away and
may have ceased to exist, nor is it my change in absolute speed - which
is a concept denied by SR. I have changed my relationship with the light
locally and the only thing which has changed is my speed.
You can wrap that up in any degree of mathematical sophistication you
like it doesn't alter the fact that it is physical nonsense. It also
exposes the weakness of accepting a mathematical model as a "physics
theory". It isn't. Physical interpretation is an essential part of
physics whether you like it or not. A mathematical model does not care
a fig whether it is describing something physically impossible. So if my
decision to change my speed requires that light started separating from
the source at a different speed a year previous in anticipation of that
decision - there is NOTHING in a mathematical model to prevent that
neither is there anything inhibiting the existence of many separate
realities simultaneously and my moving from one to another.
As I say above. Having used all sorts of spin, reflected in text books
students can go through their career without it ever being corrected.
Tom Roberts for example is confused.
Me : The wavelength is a function of the speed of separation of the
light at the source 1 ly away.
Tom: This is grotesquely wrong.
Me It is absolutely right.
Tom: Nonsense. The "speed of separation of the light at the source" is
c, a single value.
Me: Only in the FoR of the source.
Tom: If wavelength were indeed a function of the speed of separation
from the source, then all light would necessarily have a single
wavelength -- it doesn't.
Your basic error is saying "the wavelength", implicitly thinking it is a
property of the light; it isn't. It requires an instrument to measure
the wavelength of light, and the value obtained depends on properties of
the instrument (e.g. its velocity wrt the source of the light).
Me: How can the RELATIVE velocity of the source affect my ruler or the
clock of my frequency counter?
Tom did not respond despite having two further opportunities to do so.
Although text books go to some length to avoid saying so it is inherent
that in the observer's FoR light separates from the source at whatever
speed is necessary for it to be c in the observer's FoR and that SR
requires that that has an affect on what you physically measure by way
of frequency.
I do not accept that a particular generation of "physicists" has a right
to say that "Physics is whatever we say it is". The dumbing-down of
physics is a highly regrettable expedient but you as an educator CANNOT
question that wisdom if you want to retain your post, anymore than
someone teaching theology can question the existence of god.
[quote]The professor's job
is to make excellent investigators of nature, highly trained in the
best methodology obtained for that purpose -- the scientific method.
It is the full expectation that students who go on to be outstanding
investigators will make a singular mark, and you'll note that awards
and honors are given to those investigators that *break* with the
status quo. You only need look at the list of Nobel laureates and
their work to understand that. Positions of investigatory freedom and
support for such work, however, comes at the cost of demonstrating
competence with the methodology. This includes understanding how to
probe the validity of ANY idea (including time-ordered determinism)
with a well-crafted experimental test, as well as being comfortable
with the mathematical toolbox that is so useful in shorthanding
underlying concepts without excess baggage.
It is NOT the job of the professor to drum into student's head this
assertion or that assertion. It IS the job of the professor to get
students to see HOW we know those things we think we do know, as well
as those things we DON'T know and how we might go about finding the
answers to them. It is the poor student that just accepts things
without asking how we know, and it is also the poor student who just
reject things without entertaining the same.
Many of his posts seem to be well honed techniques
of presentation which carefully avoid problems. Others are put-downs
intended for the more difficult student and intended to make a student
look small - as if he has made a really stupid remark - when in fact he
is thinking for himself. If that be the case then acknowledgement =
failure i.e. if he is forced to admit to his students that the subject
he is teaching is fundamentally flawed he can't do his job.
Forgive me if this sounds like sour grapes, uttered by someone who has
felt inadequate in the study of physics and finds it confusing.
[/quote]
I never suggested that you felt inadequate or that you find it
confusing. I credit you with believing in what you are doing. That it is
in the best interests of your students.ou
[quote]Might
I suggest you try again with an education in the subject, being more
selective with both your materials and your teachers?
[/quote]
Perhaps some other educator would succeed where you have failed )
I am certainly not going to be convinced by anyone trying to convince me
by distorting history, applying spin, and bullying tactics and I am now
an expert at spotting those techniques.
[quote]I don't object you or anyone thinking for yourself. However, if you've
not availed yourself of the information that is pertinent to your
ponderings,
[/quote]
What information would that be.
[quote]then you have some work to do and that burden does lie on
you -- unless you've *paid* for the service of being guided through
it.
If it your belief that you are entitled to an education that
satisfies you on Usenet, then I'm afraid I have bad news.
[/quote]
You can find things on the Internet which no educator would want in his
text book - not because they are not true but because they would make
his life difficult.
Perhaps I should try a historian to get a balanced view. Perhaps I
should study Sir Edmund Whittaker's The History of Theories of Aether
and Electricity - trouble is it runs to several volumes. Apparently
there is a chapter on relativity, entitled, "The Relativity Theory of
Poincare and Lorentz." Einstein is mentioned for the first time in a
paragraph on the thirteenth page.
"(1905) Einstein published a paper which set forth the relativity
theory of Poincare and Lorentz with some amplification, and which
attracted much attention. He asserted as a fundamental principle the
constancy of the velocity of light, i.e., that the velocity of light in
a vacuum is the same in all systems of reference which are moving
relatively to each other, an assertion which at the time was widely
accepted. In this paper Einstein gave modifications which must now be
introduced into the formulae for aberration and for the Doppler effect."
--
John Kennaugh "... what at its beginnings is recognised as a speculation, with
greater or less plausibility, develops with time into a compulsory dogma, which
whosoever disbelieves thereby brands himself as an ignorant fool." Dingle |
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| eric gisse... |
| Posted: Sat Nov 07, 2009 8:27 am |
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John Kennaugh wrote:
[...]
[quote]It is therefore nonsensical to say that "the kinetic energy of a
single object can be zero and nonzero at the same time in two different
reference frames". The kinetic energy of a single object is a
meaningless concept (except for rotational kinetic energy which we are
not dealing with here).
Fascinating. And yet kinetic theory makes extensive use of the kinetic
energy of the individual elements in the medium.
Do you have any references from classical physics that support your
position on this?
Do you have any logical argument against my position?
[/quote]
Is it your intent to look like a fool?
In the few sentence above, you have demonstrated that...
* you don't understand classical physics, specifically the concepts of the
reference frame and relativity.
* you don't understand kinetic theory, which is the underlying basis of your
dumb-as-shit argument.
* you don't know that there is no such thing as 'rotational kinetic energy',
closely related to you not understanding classical physics. If you meant to
say 'angular momentum', congratulations you confused energy and momentum and
expect to be taken seriously.
[... |
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| doug... |
| Posted: Sat Nov 07, 2009 9:43 am |
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John Kennaugh wrote:
[quote]PD wrote:
On Nov 1, 5:39 am, John Kennaugh <J... at (no spam) notworking.freeserve.co.uk
wrote:
Paul Stowe wrote:
On Oct 31, 7:08 am, PD <thedraperfam... at (no spam) gmail.com> wrote:
On Oct 31, 5:49 am, John Kennaugh <J... at (no spam) notworking.freeserve.co.uk
snip for brevity.
You *believe* that relativity is correct and that the modern physics
built upon that foundation is both sound and fascinating.
[/quote]
And that belief is built on a century of experiements which you
are totally ignorant of so you come here to look stupid.
It is in the
[quote]interests of your students that they be persuaded and that justifies the
tactics you employ. Once over the initial difficulty you are confident
that when the student sees what has been built on those less than
satisfactory foundations he will realise that where they originated
doesn't matter.
From your point of view it is legitimate to use spin and carefully
chosen ways of presenting it. Hence I spotted you as an educator because
you have been treating me as a troublesome student.
[/quote]
No, you are an ignorant person who pretends he has all the answers
with his prejudices but who is knows nothing of science.
Applying all the
[quote]tricks and techniques you have developed over the years to get a student
on board (for his own good) even resorting to ridicule suggesting that
my problem was with Classical mechanics - which was a tad dishonest you
must admit.
[/quote]
Well, the fact that you were spouting nonsense was a pretty
good clue that you do not know classical mechanics.
Hence my comment that you are intelligent enough to know
[quote]that you are being dishonest.
One problem is that at the end of the course you do not go back and put
it right. Students leave with a totally false sense of the origins of SR
and continue to believe the myth throughout their career.
People compiling text books do so to make money. To do that they require
that educators choose their book as the 'course book' and for that to
happen they have to help the educator side step the difficult issues.
You want to give the students the impression that there was no
alternative to relativity so the chosen book will not mention Ritz.
[/quote]
Ritz was shown to be wrong and is only of historical interest.
But there were lots of others who were wrong.
If
[quote]it did you might get bogged down trying to explain why his theory was
rejected and that would be difficult - so best not mention him.
[/quote]
The explanation is short: Experiments showed him to be wrong.
If the
[quote]subject was raised you might have to distort history (as you have tried
with me) mentioning experiments which occurred long after the event,
without making that clear.
[/quote]
The results of the experiment show how the universe is. Are you
disputing that or are you suggesting the universe changed its
mind?
[quote]
It is also a good idea for a book to play down the role of Lorentz, even
going as far as leaving the false impression that his length contraction
was a rather silly ad-hoc assumption when it wasn't. Lorentz was a first
rate physicist but you have to sell Einstein - who wasn't (personal
opinion) and as far as SR is concerned came up with nothing which
Lorentz had not already come up with.
[/quote]
You keep showing your ignorance of science.
You will perpetuate the myth that
[quote]Einstein came up with a marvellous theory which showed the aether to be
unnecessary. This isn't true, Physics quite arbitrarily changed its own
definition as to what a theory was
[/quote]
Again you show your ignorance of science. Your prejudices do not
count as science.
and deemed physical interpretation
[quote]unnecessary - thus the aether, as the physical explanation previously
underpinning physical theory became redundant. It did not result from
anything Einstein did (he supported the aether concept) but from the
desire by others to accept his theory despite him not having come up
with a theoretical structure to replace the one of Lorentz which he had
objected to.
[/quote]
Oh, my.
[quote]
The book will typically place great emphasis on Maxwell's *equations* to
avoid mention of the key role of the aether. The fact is that history
makes no sense without the aether, without something you have to teach
is a silly idea. A text book can safely claim that Maxwell's equations
imply whatever it wants - a first year student won't understand them so
cannot challenge it.
[/quote]
Clearly you do not understand them yet.
[quote]
When my interest in relativity was first kindled I realised that the
book I had was using semantic slight of hand - "the MMX has showed that
an observer's speed did not affect the speed of light" (not actually
untrue IN CONTEXT of the MMX although it would be more accurate to talk
of the speed of the observer's apparatus). By using identical wording in
the relativity chapter it tried to leave the impression that the second
postulate follows directly from the MMX i.e. that it had been
experimentally proven. It appears that some people around here still
believe that and they are in good company. Stephen Hawking has
apparently based his life's work on that belief. I found the same
technique in several books - authors look to see how other books get
around a difficulty.
I realised the problem presented by Doppler shift. By definition Doppler
frequency shift is the result in a change of speed relative to the wave.
Text books tend to avoid it for good reason. I looked in various text
books - they side stepped the issue talking about train whistles and
"similar principles apply". I only found one book which attempted to
deal with it differently and when I had got my head around the over
complicated description, it was attempting to draw a distinction between
speed and rate of change of distance!
[/quote]
Yes, we know that you keep repeating the same nonsense about having
an effect on the source a year away. That is laughably wrong and
you keep showing your ignorance.
[quote]
I eventually realised that text books only ever describe light leaving a
source as viewed from the source's FoR. This was what was inhibiting my
understanding. In the observer's FoR the source is an object like any
other object and SR requires that light travels at c w.r.t the FoR not c
w.r.t every object moving in the FoR and it is therefore not c w.r.t a
source moving in the observers FoR. "Oh yes it is" I was told. It
eventually became clear that physics has hijacked the English language
so that it was almost impossible to express this idea. I was told that
no matter what lengths I went to, to explain that I was describing it
from the PoV of the observer's FoR that as soon as I wrote "w.r.t. the
source" it was taken to mean that I had changed my FoR to that of the
source. I have had to learn my own semantic work-around. In an
observer's FoR light can have a speed of separation from the source
between 0 and 2c as is the case of the speed of separation or closure of
any other object in the observer's FoR.
[/quote]
Yes, you really have not understood relativity.
[quote]
In Sound there are two different physical mechanisms producing Doppler.
Change in the speed of the source (freq changes because the wave
separates from the source at a slower speed ahead of the source and
faster behind the source so wavelengths are compressed forward and
stretched behind it), and observer moving (freq change because he is
passing the wavecrests at a different speed).
There is only one mathematical basis for Doppler in SR and that is a
change in the speed of separation from the source generating different
wavelengths. This has to act for both a change of speed of the source
and a change of speed of the observer thus avoiding the need for the
speed of the wave relative to the observer ever changing as one might
expect if the observer changes his speed. There is a problem with that.
If I change my speed the frequency changes instantly. Clearly It is not
my change in speed w.r.t the light source - which may be 1 ly away and
may have ceased to exist, nor is it my change in absolute speed - which
is a concept denied by SR. I have changed my relationship with the light
locally and the only thing which has changed is my speed.
[/quote]
You assume that if you get a wrong answer from your ignorance that
the universe must change to agree with your mistake.
[quote]
You can wrap that up in any degree of mathematical sophistication you
like it doesn't alter the fact that it is physical nonsense.
[/quote]
No, it is your ignorance.
It also
[quote]exposes the weakness of accepting a mathematical model as a "physics
theory". It isn't. Physical interpretation is an essential part of
physics whether you like it or not.
[/quote]
This desire is clearly not helping you at all.
A mathematical model does not care
[quote]a fig whether it is describing something physically impossible.
[/quote]
If the experiments agree with the equations, then they are right.
It means your prejudices were wrong. See QM.
So if my
[quote]decision to change my speed requires that light started separating from
the source at a different speed a year previous in anticipation of that
decision - there is NOTHING in a mathematical model to prevent that
neither is there anything inhibiting the existence of many separate
realities simultaneously and my moving from one to another.
[/quote]
There is only your ignorance of what relativity says.
[quote]
As I say above. Having used all sorts of spin, reflected in text books
students can go through their career without it ever being corrected.
Tom Roberts for example is confused.
[/quote]
Well, no. You look like a fool trying to talk to Tom.
[quote]
Me : The wavelength is a function of the speed of separation of the
light at the source 1 ly away.
Tom: This is grotesquely wrong.
Me It is absolutely right.
[/quote]
Tom is correct.
[quote]
Tom: Nonsense. The "speed of separation of the light at the source" is
c, a single value.
Me: Only in the FoR of the source.
Tom: If wavelength were indeed a function of the speed of separation
from the source, then all light would necessarily have a single
wavelength -- it doesn't.
Your basic error is saying "the wavelength", implicitly thinking it is a
property of the light; it isn't. It requires an instrument to measure
the wavelength of light, and the value obtained depends on properties of
the instrument (e.g. its velocity wrt the source of the light).
Me: How can the RELATIVE velocity of the source affect my ruler or the
clock of my frequency counter?
Tom did not respond despite having two further opportunities to do so.
[/quote]
He was too busy laughing at you as well as realizing that you are
here to bluster in your ignorance and have no interest in truth.
You are only here to say that you do not like relativity.
[quote]Although text books go to some length to avoid saying so it is inherent
that in the observer's FoR light separates from the source at whatever
speed is necessary for it to be c in the observer's FoR and that SR
requires that that has an affect on what you physically measure by way
of frequency.
I do not accept that a particular generation of "physicists" has a right
to say that "Physics is whatever we say it is".
[/quote]
Physics is what the universe says it is. You do not want to accept
that and want your prejudices. That is why you cannot understand
science.
The dumbing-down of
[quote]physics is a highly regrettable expedient but you as an educator CANNOT
question that wisdom if you want to retain your post, anymore than
someone teaching theology can question the existence of god.
The professor's job
is to make excellent investigators of nature, highly trained in the
best methodology obtained for that purpose -- the scientific method.
It is the full expectation that students who go on to be outstanding
investigators will make a singular mark, and you'll note that awards
and honors are given to those investigators that *break* with the
status quo. You only need look at the list of Nobel laureates and
their work to understand that. Positions of investigatory freedom and
support for such work, however, comes at the cost of demonstrating
competence with the methodology. This includes understanding how to
probe the validity of ANY idea (including time-ordered determinism)
with a well-crafted experimental test, as well as being comfortable
with the mathematical toolbox that is so useful in shorthanding
underlying concepts without excess baggage.
It is NOT the job of the professor to drum into student's head this
assertion or that assertion. It IS the job of the professor to get
students to see HOW we know those things we think we do know, as well
as those things we DON'T know and how we might go about finding the
answers to them. It is the poor student that just accepts things
without asking how we know, and it is also the poor student who just
reject things without entertaining the same.
Many of his posts seem to be well honed techniques
of presentation which carefully avoid problems. Others are put-downs
intended for the more difficult student and intended to make a student
look small - as if he has made a really stupid remark - when in fact he
is thinking for himself. If that be the case then acknowledgement =
failure i.e. if he is forced to admit to his students that the subject
he is teaching is fundamentally flawed he can't do his job.
Forgive me if this sounds like sour grapes, uttered by someone who has
felt inadequate in the study of physics and finds it confusing.
I never suggested that you felt inadequate or that you find it
confusing. I credit you with believing in what you are doing. That it is
in the best interests of your students.ou
[/quote]
No, you find physics very confusing and demonstrate that through
the stupid statements you make in every post.
[quote]
Might
I suggest you try again with an education in the subject, being more
selective with both your materials and your teachers?
Perhaps some other educator would succeed where you have failed )
I am certainly not going to be convinced by anyone trying to convince me
by distorting history, applying spin, and bullying tactics and I am now
an expert at spotting those techniques.
[/quote]
No, you do not want to learn so you will remain stupid. Why are you
proud of being a fool?
[quote]
I don't object you or anyone thinking for yourself. However, if you've
not availed yourself of the information that is pertinent to your
ponderings,
What information would that be.
[/quote]
How about all of science.
[quote]
then you have some work to do and that burden does lie on
you -- unless you've *paid* for the service of being guided through
it.
If it your belief that you are entitled to an education that
satisfies you on Usenet, then I'm afraid I have bad news.
You can find things on the Internet which no educator would want in his
text book - not because they are not true but because they would make
his life difficult.
Perhaps I should try a historian to get a balanced view. Perhaps I
should study Sir Edmund Whittaker's The History of Theories of Aether
and Electricity - trouble is it runs to several volumes. Apparently
there is a chapter on relativity, entitled, "The Relativity Theory of
Poincare and Lorentz." Einstein is mentioned for the first time in a
paragraph on the thirteenth page.
"(1905) Einstein published a paper which set forth the relativity
theory of Poincare and Lorentz with some amplification, and which
attracted much attention. He asserted as a fundamental principle the
constancy of the velocity of light, i.e., that the velocity of light in
a vacuum is the same in all systems of reference which are moving
relatively to each other, an assertion which at the time was widely
accepted. In this paper Einstein gave modifications which must now be
introduced into the formulae for aberration and for the Doppler effect."
[/quote]
Oh, my, you think quoting a random paragraph from a history book
constitutes studying physics.
[quote]
[/quote] |
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| John Polasek... |
| Posted: Sat Nov 07, 2009 1:43 pm |
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On Sat, 7 Nov 2009 13:00:52 +0000, John Kennaugh
<JKNG at (no spam) notworking.freeserve.co.uk> wrote:
[quote]PD wrote:
On Nov 1, 5:39 am, John Kennaugh <J... at (no spam) notworking.freeserve.co.uk
wrote:
Paul Stowe wrote:
On Oct 31, 7:08 am, PD <thedraperfam... at (no spam) gmail.com> wrote:
On Oct 31, 5:49 am, John Kennaugh <J... at (no spam) notworking.freeserve.co.uk
snip for brevity.
snip
In Sound there are two different physical mechanisms producing Doppler.
Change in the speed of the source (freq changes because the wave
separates from the source at a slower speed ahead of the source and
faster behind the source so wavelengths are compressed forward and
stretched behind it), and observer moving (freq change because he is
passing the wavecrests at a different speed).
There is only one mathematical basis for Doppler in SR and that is a
change in the speed of separation from the source generating different
wavelengths. This has to act for both a change of speed of the source
and a change of speed of the observer thus avoiding the need for the
speed of the wave relative to the observer ever changing as one might
expect if the observer changes his speed. There is a problem with that.
If I change my speed the frequency changes instantly. Clearly It is not
my change in speed w.r.t the light source - which may be 1 ly away and
may have ceased to exist, nor is it my change in absolute speed - which
is a concept denied by SR. I have changed my relationship with the light
locally and the only thing which has changed is my speed.
You can wrap that up in any degree of mathematical sophistication you
like it doesn't alter the fact that it is physical nonsense. It also
exposes the weakness of accepting a mathematical model as a "physics
theory". It isn't. Physical interpretation is an essential part of
physics whether you like it or not. A mathematical model does not care
a fig whether it is describing something physically impossible. So if my
decision to change my speed requires that light started separating from
the source at a different speed a year previous in anticipation of that
decision - there is NOTHING in a mathematical model to prevent that
neither is there anything inhibiting the existence of many separate
realities simultaneously and my moving from one to another.
As I say above. Having used all sorts of spin, reflected in text books
students can go through their career without it ever being corrected.
Tom Roberts for example is confused.
Me : The wavelength is a function of the speed of separation of the
light at the source 1 ly away.
Tom: This is grotesquely wrong.
Me It is absolutely right.
Tom: Nonsense. The "speed of separation of the light at the source" is
c, a single value.
Me: Only in the FoR of the source.
Tom: If wavelength were indeed a function of the speed of separation
from the source, then all light would necessarily have a single
wavelength -- it doesn't.
Your basic error is saying "the wavelength", implicitly thinking it is a
property of the light; it isn't. It requires an instrument to measure
the wavelength of light, and the value obtained depends on properties of
the instrument (e.g. its velocity wrt the source of the light).
Me: How can the RELATIVE velocity of the source affect my ruler or the
clock of my frequency counter?
Tom did not respond despite having two further opportunities to do so.
Although text books go to some length to avoid saying so it is inherent
that in the observer's FoR light separates from the source at whatever
speed is necessary for it to be c in the observer's FoR and that SR
requires that that has an affect on what you physically measure by way
of frequency.
John, I invite you to look at my writeup in sci.physics for a new[/quote]
insight:
Question on the Doppler Effect Equations 11-4-9.
The volume of text you devoted above attests to the fact that Doppler
is tricky stuff. The wavelength doesn't stretch, but that's beside the
point.
Every one of five references I looked at has it wrong--it may be hard
to believe. I have a new way to analyze Doppler, based simply on the
time delay D/c and ending up with a frequency ratio
f/f0 = 1-v/c.
This contradicts the widely quoted (wrong) version:
f/f0 = 1/1+v/c
When you invert this for wavelength ratio you get
L/L0 = 1+v/c = 1+z
Which implies v/c = z, which is profoundly wrong, because
v/c = z/1+z (not z)
This clearly should cause major revisions where terms cz and cz/H0 are
used.
John Polasek |
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| Androcles... |
| Posted: Sat Nov 07, 2009 2:05 pm |
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Guest
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"John Polasek" <jpolasek at (no spam) cfl.rr.com> wrote in message
news:jlebf550gaf3bluot2e64im0qkeubo9k0p at (no spam) 4ax.com...
[quote]John, I invite you to look at my writeup in sci.physics for a new
insight:
Question on the Doppler Effect Equations 11-4-9.
The volume of text you devoted above attests to the fact that Doppler
is tricky stuff. The wavelength doesn't stretch, but that's beside the
point.
Every one of five references I looked at has it wrong--it may be hard
to believe. I have a new way to analyze Doppler, based simply on the
time delay D/c and ending up with a frequency ratio
f/f0 = 1-v/c.
This contradicts the widely quoted (wrong) version:
f/f0 = 1/1+v/c
When you invert this for wavelength ratio you get
L/L0 = 1+v/c = 1+z
Which implies v/c = z, which is profoundly wrong, because
v/c = z/1+z (not z)
This clearly should cause major revisions where terms cz and cz/H0 are
used.
[/quote]
Parsing left to right, division takes precedence over addition.
f/f0 = 1/1+v/c <> 1/(1+v/c) because 1/1 =1. |
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| John Polasek... |
| Posted: Sat Nov 07, 2009 6:01 pm |
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On Sat, 7 Nov 2009 19:05:36 -0000, "Androcles"
<Headmaster at (no spam) Hogwarts.physics_p> wrote:
[quote]
"John Polasek" <jpolasek at (no spam) cfl.rr.com> wrote in message
news:jlebf550gaf3bluot2e64im0qkeubo9k0p at (no spam) 4ax.com...
John, I invite you to look at my writeup in sci.physics for a new
insight:
Question on the Doppler Effect Equations 11-4-9.
The volume of text you devoted above attests to the fact that Doppler
is tricky stuff. The wavelength doesn't stretch, but that's beside the
point.
Every one of five references I looked at has it wrong--it may be hard
to believe. I have a new way to analyze Doppler, based simply on the
time delay D/c and ending up with a frequency ratio
f/f0 = 1-v/c.
This contradicts the widely quoted (wrong) version:
f/f0 = 1/1+v/c
When you invert this for wavelength ratio you get
L/L0 = 1+v/c = 1+z
Which implies v/c = z, which is profoundly wrong, because
v/c = z/1+z (not z)
This clearly should cause major revisions where terms cz and cz/H0 are
used.
Parsing left to right, division takes precedence over addition.
f/f0 = 1/1+v/c <> 1/(1+v/c) because 1/1 =1.
Andy:[/quote]
That's all you've got? That's it?
Thanks for letting me off easy this time!
(Algebra never was one of my strengths, but I can always count on you
to show up with one of your ineffable pearls of wisdom).
I think I was trying to say that we need to do something about some of
those plots that, without apology, show e.g., cz = 900,000 km/s for z
= 3, when my equations show that for z = 3, v/c is only 0.75,
Therefore the corresponding true velocity would be 225,000 km/s, not
900,000.
I am saying that errors like that are intolerable-can we agree on
that? (or it's okay if you don't want to).
John Polasek |
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| Paul Stowe... |
| Posted: Sat Nov 07, 2009 6:18 pm |
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On Nov 7, 8:56 am, Paul Stowe <theaether... at (no spam) gmail.com> wrote:
[quote]On Nov 6, 3:19 pm, PD <thedraperfam... at (no spam) gmail.com> wrote:
[/quote]
{Snip...}
[quote]Look back in this thread and the equation is given...
The one that was given was this:
A_d = (-fu/c)v
Where f = the aether's momentum flux (kg/m-sec^2) = 6.74E+00
u = the mass attenuation coefficient (m^2/kg) = 3.15E-06
c = the Root Mean Speed of the aether (m/sec) = 3.00E+08
v = the net speed of the mass in m/sec
It's interesting that this expression does not include the mass of the
object in the aether, which means that a bowling ball is decelerated
at the same rate as a helium balloon of the same volume, and at the
same rate as a proton.
It also predicts a sizable energy loss from stars to the surrounding
medium, so that 1/r^2 radiative scaling would not apply. This is
easily testable.
It also predicts a sizable delay between particles observed from
stellar sources, compared to the photon equivalents. We can measure
the speed of the particles upon their arrival at the observatory (with
a TOF or Cerenkov counter, eg.), use the relation above to integrate
what the source speed was, and then use that velocity profile to track
back the time of the release of the particles compared to that of the
light. This time would be much earlier than a similar traceback that
assumes the particles traveled at constant speed from the origin. If
the origin time is weeks before the origin of the light, would this
make you suspect that the relation has a problem?
What I don't see is anything quantitive from you... It was 'you' who
claimed Vern's process proved something, not him, so show us the
numbers & analysis to back that up.
Particle buckets are timed at fixed target machines (free flight
beamlines) to a precision of 12 ps. The FNAL beamline out to the first
MINOS station is about 2.5 km. The transit time of particles out to
that location from extraction is 8 usec.
At 2.5 km with speed c it's 8.34E-06 usec. If the precision is +/- 12
psec, that's 4 orders of magnitude too large to see the predicted
change in the arrival time due to aether deceleration and that's EVEN
IF! you could separate it from an imparted energy vavriance.
The transit time to the
second station is 2.4 msec. And that's a SHORT throw, compared to
stellar generators.
If m is mil, then at c that's 72 km. At that distance the delay in
arrival would be ~24 psec, a change in 1 part in 10^8. Again, there
is no way you can separate this from imparted energy to the
particle... Thus your 'off the cuff' claim,
"... As it turns out, though (and this is the way it
should be), nature has made its unbiased evaluation
-- and the ether model's prediction tanked."
is false, and in fact at (no spam) 12.2 kps the predicted deceleration is 8.6E-10
m/sec^2 and the Pioneer spacecraft moving at ~12.2 kps when compared
to a measured deceleration of 8.7E-10 +/- 1.33 m/sec^2 matches the
long term (20 yrs) observation. Thus it is just the opposite of your
bluster, it is the aether model that clearly is shown by observation
to be the correct predictor. There is more of course, that same model
says the big G is the product of two physical terms, aether flux (f)
and a mass attenuation coefficient (u) such that,
G = fu^2 (6.74)(3.147E-06)^2 -> 6.673E-11 m^3/kg-sec^2
and has NO! expectation of being constant since in a medium the
momentum flux is a function of density, and, as we all know, density
can vary with position. As we also know, wave speed c also varies
with density. Thus in that case, IN the EFEs G and c cannot be taken
as constants.
Do you find it strange that a feather would decelerate at the same
rate as a uranium bowling ball? Where else is this property seen?
When something is receding from a large gravitational mass. Not when
one is traveling perpendicular to one, for example.
This just indicates your lack of understanding the model. In the weak
limit the aether 'field' acts equally upon all sub-atomic constituents
uniformly, thus bulk mass plays no role in such a process.
[/quote]
Just a followup, other spacecraft also perfectly match this formula,
Ulysses moving at an average of ~17 kps -> 1.2E-09m/sec^2 and the
observed overall drag is 12E-10 +/- 3 which is a speed range of 12.7
to 21.2 kps
Per: http://arxiv.org/PS_cache/gr-qc/pdf/9808/9808081v2.pdf
Data: http://ulysses-ops.jpl.esa.int/ulsfct/images/grsunrng.gif |
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| Androcles... |
| Posted: Sat Nov 07, 2009 7:08 pm |
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Guest
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"John Polasek" <jpolasek at (no spam) cfl.rr.com> wrote in message
news:7rtbf51d2frlbms8mkp0eq6tc52e5b0f7p at (no spam) 4ax.com...
[quote]On Sat, 7 Nov 2009 19:05:36 -0000, "Androcles"
Headmaster at (no spam) Hogwarts.physics_p> wrote:
"John Polasek" <jpolasek at (no spam) cfl.rr.com> wrote in message
news:jlebf550gaf3bluot2e64im0qkeubo9k0p at (no spam) 4ax.com...
John, I invite you to look at my writeup in sci.physics for a new
insight:
Question on the Doppler Effect Equations 11-4-9.
The volume of text you devoted above attests to the fact that Doppler
is tricky stuff. The wavelength doesn't stretch, but that's beside the
point.
Every one of five references I looked at has it wrong--it may be hard
to believe. I have a new way to analyze Doppler, based simply on the
time delay D/c and ending up with a frequency ratio
f/f0 = 1-v/c.
This contradicts the widely quoted (wrong) version:
f/f0 = 1/1+v/c
When you invert this for wavelength ratio you get
L/L0 = 1+v/c = 1+z
Which implies v/c = z, which is profoundly wrong, because
v/c = z/1+z (not z)
This clearly should cause major revisions where terms cz and cz/H0 are
used.
Parsing left to right, division takes precedence over addition.
f/f0 = 1/1+v/c <> 1/(1+v/c) because 1/1 =1.
Andy:
That's all you've got? That's it?
Thanks for letting me off easy this time!
[/quote]
Oh, but I'm usually gentle with kiddywinks learning the basics
for the first time.
[quote]
(Algebra never was one of my strengths, but I can always count on you
to show up with one of your ineffable pearls of wisdom).
[/quote]
Of course you can count on me. I advise you to use parentheses
redundantly, it does no harm and a computer (compiler) doesn't
mind at all.
For example,
3+1*4^2+1 = 20, but
(3+1*4)^(2+1) = 343 and
((3+1)*4)^2+1 = 65 which is the same as (((3+1)*4)^2+1)
http://en.wikipedia.org/wiki/Parsing
If you include parentheses for every pair of values and their
binary operator there can be no ambiguity.
A computer can only calculate pairs of values and it does it
sequentially.
1+2+3 = 6, the computer first produces 1+2 = 3 and
adds 3 to that. If you write 1+ (2+3) it will store the 1,
compute 2+3 = 5 and then add the 1 it stored. The result is
the same but the order changes.
[quote]I think I was trying to say that we need to do something about some of
those plots that, without apology, show e.g., cz = 900,000 km/s for z
= 3, when my equations show that for z = 3, v/c is only 0.75,
Therefore the corresponding true velocity would be 225,000 km/s, not
900,000.
I am saying that errors like that are intolerable-can we agree on
that? (or it's okay if you don't want to).
John Polasek
[/quote]
Errors are always intolerable, John.
Saying "wavelength doesn't stretch" is pretty meaningless.
All velocities are relative, and since you are not comfortable with
algebra I've drawn a picture to prove wavelengths are relative too.
http://www.androcles01.pwp.blueyonder.co.uk/Wave/Relative.gif
Algebraically, if
c = \lambda * \nu
or, easier, c = w*f
then w is a length and f is a frequency,
and since frequency = 1/duration
then
c = length/duration = x/t and dx/dt is a velocity.
Doppler isn't really all that difficult, many people have more
difficulty with relative motion.
You should really try my little quiz below.
Match the caption to the gif:
A) http://tinyurl.com/lv2fl7
B) http://tinyurl.com/njgouh
C) http://tinyurl.com/klkfc9
D) http://tinyurl.com/l6lt4g
1) applies to light (in vacuum) and sound (in air)
2) applies to light but not sound
3) applies to sound but not light
4) applies to neither light nor sound |
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| Paul Stowe... |
| Posted: Sun Nov 08, 2009 8:45 am |
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Guest
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On Nov 7, 8:54 am, PD <thedraperfam... at (no spam) gmail.com> wrote:
[quote]On Nov 7, 7:00 am, John Kennaugh <J... at (no spam) notworking.freeserve.co.uk
wrote:
PD wrote:
On Nov 1, 5:39 am, John Kennaugh <J... at (no spam) notworking.freeserve.co.uk
wrote:
PaulStowewrote:
On Oct 31, 7:08 am, PD <thedraperfam... at (no spam) gmail.com> wrote:
On Oct 31, 5:49 am, John Kennaugh <J... at (no spam) notworking.freeserve.co.uk
snip for brevity.
I'm sorry, but here I have to object. You have NO idea, obviously,
what a professor's role is in teaching students.
Before you can teach them any of that you have first to get them to
accept certain things which they may be reluctant to accept. SR being
the most obvious. You cannot go honestly through the history and show
that it follows logically because it doesn't. It is what you would call
counter-intuitive (I might describe it in more earthy language).
You really have no choice in that you have to persuade your students to
accept relativity because unless they do you cannot move on. In fact if
you cannot persuade a student, your only option is to suggest he takes
another course of study.
This is flat wrong. Let me give you a simple example to illustrate.
In FIRST semester physics, students are taught a number of things and
why we have come to believe that they are correct.
For example, that velocities transform from one inertial reference
frame by simple vector addition with the relative velocity between
frames.
For example, that momentum is mv, and that kinetic energy is mv^2/2.
For example, that the mass of a system is the sum of the masses of the
objects in that system.
For example, that the universal law of gravitation that seems to work
for everything is given by F = GMm/r^2.
Now, it would be foolish of you to say that we expect students to
*accept* these statements because they have to, otherwise they cannot
go on. We do not expect students to *accept* these statements because
we know FULL WELL that by the end of the second semester, we will have
told those same students that those statements are wrong, and how we
know they are wrong.
[/quote]
Actually, you do 'expect' students to accept these tenets. I've
personally seen the Prof denigrate students for challenging
presentations. They are also damned well expected to learn and use
them in testing. Now, you might expect to 'lead' them to the more
modern variants in the future but students learn quickly that being
argumenative is counter productive. The tenet 'shut up & learn' comes
to mind...
[quote]Teaching science is not at all about what statements to accept. It is
teaching them how the process of induction of physical laws works: why
we believe they are right, how they are tested, how they are applied,
and then what to do when we find cases where the application does not
seem to work so well.
[/quote]
Ah, if only such ideals held for all... As you should be aware, the
style and methods of teaching is as varied as are the personalities of
the teachers. I remember in my QM courses I was told, don't try to
figure it out just learn the rules and how to use the equations. John
is right here.
[quote]It is clear that YOU were led to believe that the statements presented
in your classes were just to be accepted. This is unfortunate, and may
be the result of a poor teacher or you being a poor student or a
combination of both. In any event, if this is what you were led to
believe, then you missed the point of your education in physics almost
completely.
[/quote]
As, apparently, have most.
[quote]You *believe* that relativity is correct and that the modern physics
built upon that foundation is both sound and fascinating.
That is actually not quite what I believe. I believe that relativity
has been extremely useful in its own right and in being one of the
struts used to build other theories (like quantum field theories) that
have also turned out to be extremely useful. I also believe that there
does not seem to be credible or reproducible evidence that indicates
that relativity is wrong -- SO FAR. This does not mean that I believe
relativity is inviolate -- just that I have no reason yet to doubt it.
[/quote]
So, what's the difference, quantitatively, between LET and SR? If
both are mathematically identical 'belief', not science is the only
real separation. One of those 'beliefs' is that, somehow, geometry
causes physicality. Both must contain the same 'geometry' but one
does not need to claim that it as a 'cause'.
[quote]It is in the
interests of your students that they be persuaded and that justifies the
tactics you employ. Once over the initial difficulty you are confident
that when the student sees what has been built on those less than
satisfactory foundations he will realise that where they originated
doesn't matter.
Yes, this is correct, because the historical thought process IS NOT
CENTRAL to the truth of the propositions. That does not hinge on
whether the right answer was inevitable from the information give, or
whether it was landed on by good instinct and practically nothing
else, or even whether the correct answer was stumbled on through a
*mistake*. The reason is that the truth is not determined by the
*deduction* but by the tests of its predictions in experiment. In
science, the deductive methodology is *completely* secondary to the
experimental verification.
[/quote]
That's a 'philosophy' that cannot be proven. I strongly disagree with
it and I think John does also. In fact, it usurps the first two steps
of the scientific method placing almost all of the emphasis on the
experiment. What in your mind is the difference in step one,
observation and step three testing?
[quote]From your point of view it is legitimate to use spin and carefully
chosen ways of presenting it. Hence I spotted you as an educator because
you have been treating me as a troublesome student.
Not troublesome, but not very promising either, because you have
missed the point almost completely about how science works. This is
not a personal slam against your intellect. It is simply pointing out
that you have missed something really important.
[/quote]
We would say the same about you. Leading to the phrase, 'open-minded
physicist' is an oxymoron'. This is nicely lampooned in the comety
"The Big Bang Theory"
[quote]Applying all the
tricks and techniques you have developed over the years to get a student
on board (for his own good) even resorting to ridicule suggesting that
my problem was with Classical mechanics - which was a tad dishonest you
must admit. Hence my comment that you are intelligent enough to know
that you are being dishonest.
One problem is that at the end of the course you do not go back and put
it right. Students leave with a totally false sense of the origins of SR
and continue to believe the myth throughout their career.
I'm sorry that you were left with some mistaken impressions in your
education and that you feel misled as a result.
I would suggest that students only come to a full appreciation of the
real development of concepts and how science works after four or six
years of concentrated immersion in it.
[/quote]
I would go farther, I would say indoctrination... I mentor students
in science and emphasise that they should not, EVER! buy 'it just is'
or take anything as a given but to ALWAY look for connections,
patterns, and commonality. That unless explicitly and unequivically
reuled out, assume that form follows function and believe only
observable indication.
[quote]It is not pedagogically useful
to dot the i's and cross the t's in the early courses, and it
CERTAINLY is not in the interests of the authors of popularizations to
do so. Those who take a special interest in crossed ts and dotted i's
are invited to further study.
[/quote]
I think that, to graduate in a core science every student should have
to take a course in the developmental history of that science. In
physics, I would use Whittaker's book as the basis for the
curriculum. In fact, I alway urge students to read it before going to
college.
[quote]People compiling text books do so to make money. To do that they require
that educators choose their book as the 'course book' and for that to
happen they have to help the educator side step the difficult issues.
No, they do not. They are adopted if they do a good job presenting the
difficult issues. I don't know what textbook you used, but most of
them that I've used are careful to point out those places where we
don't yet have a full understanding. However, they DO present things
that they will later retract, or that they know will have to be looped
back upon in later courses.
You want to give the students the impression that there was no
alternative to relativity so the chosen book will not mention Ritz. If
it did you might get bogged down trying to explain why his theory was
rejected and that would be difficult - so best not mention him. If the
subject was raised you might have to distort history (as you have tried
with me) mentioning experiments which occurred long after the event,
without making that clear.
There are ALWAYS choices made in presenting materials. There are
*hundreds* of alternative models that are available to choose from in
any given chapter of any given book. The fact that your favorite is
not brought up in the book you chose is not suppression, it is page-
count management.
[/quote]
That's a politically cop-out, you're right you don't want to
contaminate young minds with obviously wrong notions. Which is why I
give my charges a heads up with Whittaker's treasties...
[quote]but you have to sell Einstein - who wasn't (personal
opinion) and as far as SR is concerned came up with nothing which
Lorentz had not already come up with. You will perpetuate the myth that
Einstein came up with a marvellous theory which showed the aether to be
unnecessary. This isn't true, Physics quite arbitrarily changed its own
definition as to what a theory was
No, sir. You are mistaken. However, it DID question itself as to what
the essential aspects of a physical theory must entail.
For example, you are under the impression that at one time a theory
had to be time-ordered and deterministic to even be considered a
theory at all. And that if anything came along that didn't feature
time-ordered determinism and it was called a theory, then it was
redefining what "physical theory" even meant. That is wrong.
[/quote]
Philosophy again, not science... Theories should explain nature.
What is the difference between a hypothesis, theory, and law?
[quote]and deemed physical interpretation
unnecessary - thus the aether, as the physical explanation previously
underpinning physical theory became redundant. It did not result from
anything Einstein did (he supported the aether concept) but from the
desire by others to accept his theory despite him not having come up
with a theoretical structure to replace the one of Lorentz which he had
objected to.
The book will typically place great emphasis on Maxwell's *equations* to
avoid mention of the key role of the aether. The fact is that history
makes no sense without the aether, without something you have to teach
is a silly idea. A text book can safely claim that Maxwell's equations
imply whatever it wants - a first year student won't understand them so
cannot challenge it.
That is also mistaken. A first year student is given the opportunity
to challenge it, but may be promised that this will be addressed in
SECOND year.
If you are so impatient that you need it addressed in the first year,
then you have the opportunity for side study.
[/quote]
I encourage the to read Maxwell's papers or Simpson's book on
Maxwell.
[quote]was using semantic slight of hand - "the MMX has showed that
an observer's speed did not affect the speed of light" (not actually
untrue IN CONTEXT of the MMX although it would be more accurate to talk
of the speed of the observer's apparatus). By using identical wording in
the relativity chapter it tried to leave the impression that the second
postulate follows directly from the MMX
You're right, that is a MISTAKEN impression. You got a mistaken
impression from the book you were reading. So? Who's to blame for
that?
[/quote]
I got the 'impression' that the Einstein's usurped the first & second
postulate from Maxwell as indicated in the title of their paper (yes,
Milvia's name was on the original submittal)
[quote]i.e. that it had been
experimentally proven.
The second postulate was certainly not proven at the time it was
posited. However, there is a WEALTH of information that has been
collected since that time.
[/quote]
I think Stokes had proved it for Continuum Mechanics by 1905...
[quote]It appears that some people around here still
believe that and they are in good company. Stephen Hawking has
apparently based his life's work on that belief. I found the same
technique in several books - authors look to see how other books get
around a difficulty.
I realised the problem presented by Doppler shift. By definition Doppler
frequency shift is the result in a change of speed relative to the wave.
No sir. That is NOT the definition of Doppler shift. If you were led
to that impression, then again you were misled.
[/quote]
"The Doppler effect (or Doppler shift), named after Austrian
physicist Christian Doppler who proposed it in 1842, is the
change in frequency of a wave for an observer moving relative
to the source of the wave. ..."
http://en.wikipedia.org/wiki/Doppler_effect
It seem's John is right here unless you wish to challenge the standard
definition.
[quote]In Sound there are two different physical mechanisms producing Doppler.
Change in the speed of the source (freq changes because the wave
separates from the source at a slower speed ahead of the source and
faster behind the source so wavelengths are compressed forward and
stretched behind it), and observer moving (freq change because he is
passing the wavecrests at a different speed).
There is only one mathematical basis for Doppler in SR and that is a
change in the speed of separation from the source generating different
wavelengths.
No, this isn't right, either.
[/quote]
I think you're quibbling...
[quote]I do not accept that a particular generation of "physicists" has a right
to say that "Physics is whatever we say it is". The dumbing-down of
physics is a highly regrettable expedient but you as an educator CANNOT
question that wisdom if you want to retain your post, anymore than
someone teaching theology can question the existence of god.
Of COURSE someone teaching theology can question the existence of God.
It is the questioning, and how those questions get answered, that is
the very basis of doing the study!
[/quote]
Then one should encourage the practice, not discourage and denigrate
it...
[quote]You can find things on the Internet which no educator would want in his
text book - not because they are not true but because they would make
his life difficult.
This is bullshit. On the internet there is no quality control and
someone with a misaligned bullshit meter will get led astray EVERY
TIME.
[/quote]
Ah, the 'we must protect people from themselves' argument. Some would
call that attempted mind control... As Feynman said, "What do you
care what other people think?" isn't that 'freedom'? |
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| John Polasek... |
| Posted: Sun Nov 08, 2009 12:07 pm |
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Guest
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On Sun, 8 Nov 2009 00:08:42 -0000, "Androcles"
<Headmaster at (no spam) Hogwarts.physics_p> wrote:
[quote]
"John Polasek" <jpolasek at (no spam) cfl.rr.com> wrote in message
news:7rtbf51d2frlbms8mkp0eq6tc52e5b0f7p at (no spam) 4ax.com...
On Sat, 7 Nov 2009 19:05:36 -0000, "Androcles"
Headmaster at (no spam) Hogwarts.physics_p> wrote:
"John Polasek" <jpolasek at (no spam) cfl.rr.com> wrote in message
news:jlebf550gaf3bluot2e64im0qkeubo9k0p at (no spam) 4ax.com...
John, I invite you to look at my writeup in sci.physics for a new
insight:
Question on the Doppler Effect Equations 11-4-9.
The volume of text you devoted above attests to the fact that Doppler
is tricky stuff. The wavelength doesn't stretch, but that's beside the
point.
Every one of five references I looked at has it wrong--it may be hard
to believe. I have a new way to analyze Doppler, based simply on the
time delay D/c and ending up with a frequency ratio
f/f0 = 1-v/c.
This contradicts the widely quoted (wrong) version:
f/f0 = 1/1+v/c
When you invert this for wavelength ratio you get
L/L0 = 1+v/c = 1+z
Which implies v/c = z, which is profoundly wrong, because
v/c = z/1+z (not z)
This clearly should cause major revisions where terms cz and cz/H0 are
used.
Parsing left to right, division takes precedence over addition.
f/f0 = 1/1+v/c <> 1/(1+v/c) because 1/1 =1.
Andy:
That's all you've got? That's it?
Thanks for letting me off easy this time!
Oh, but I'm usually gentle with kiddywinks learning the basics
for the first time.
(Algebra never was one of my strengths, but I can always count on you
to show up with one of your ineffable pearls of wisdom).
This was just my attempt at sardonic humor-but apparently you don't[/quote]
get it. No, let me be more specific: you don't get it, because as you
drone on, pontificating about the merits of affixing parentheses at
each and every opportunity, you're missing the big picture.
Your interest appears to be less cosmological, and more focused on
writing code that will compile.
[quote]Of course you can count on me. I advise you to use parentheses
redundantly, it does no harm and a computer (compiler) doesn't
mind at all.
For example,
3+1*4^2+1 = 20, but
(3+1*4)^(2+1) = 343 and
((3+1)*4)^2+1 = 65 which is the same as (((3+1)*4)^2+1)
http://en.wikipedia.org/wiki/Parsing
If you include parentheses for every pair of values and their
binary operator there can be no ambiguity.
A computer can only calculate pairs of values and it does it
sequentially.
1+2+3 = 6, the computer first produces 1+2 = 3 and
adds 3 to that. If you write 1+ (2+3) it will store the 1,
compute 2+3 = 5 and then add the 1 it stored. The result is
the same but the order changes.
I think I was trying to say that we need to do something about some of
those plots that, without apology, show e.g., cz = 900,000 km/s for z
= 3, when my equations show that for z = 3, v/c is only 0.75,
Therefore the corresponding true velocity would be 225,000 km/s, not
900,000.
I am saying that errors like that are intolerable-can we agree on
that? (or it's okay if you don't want to).
John Polasek
Errors are always intolerable, John.
Saying "wavelength doesn't stretch" is pretty meaningless.
It's just to highlight the fact that most attempts at analysis of[/quote]
the Doppler effect struggle to show that the wavelength stretches
during the process, see for example Weisstein and therefore end up
with the wrong results.
[quote]All velocities are relative, and since you are not comfortable with
algebra I've drawn a picture to prove wavelengths are relative too.
http://www.androcles01.pwp.blueyonder.co.uk/Wave/Relative.gif
Algebraically, if
c = \lambda * \nu
or, easier, c = w*f
then w is a length and f is a frequency,
and since frequency = 1/duration
then
c = length/duration = x/t and dx/dt is a velocity.
Doppler isn't really all that difficult, many people have more
difficulty with relative motion.
You should really try my little quiz below.
Match the caption to the gif:
A) http://tinyurl.com/lv2fl7
B) http://tinyurl.com/njgouh
C) http://tinyurl.com/klkfc9
D) http://tinyurl.com/l6lt4g
1) applies to light (in vacuum) and sound (in air)
2) applies to light but not sound
3) applies to sound but not light
4) applies to neither light nor sound
I looked at a couple of your cartoons have to say they're neither[/quote]
instructive nor correct. They have a hypnotic effect after 30 seconds.
In #B, the source of the sound is moving ahead at the same speed as
the sound wave itself. I can't immediately picture that.
Equations are good, vector diagrams are good, but cartoons are just
entertaining. For example, favor me with one equation that is made
evident by its corresponding cartoon.
John Polasek |
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