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Posted: Thu Jun 26, 2008 2:32 pm
Guest
On Fri, 20 Jun 2008 22:12:15 -0400, Yousuf Khan <bbbl67 at (no spam) yahoo.com>
wrote:

Quote:
Pentcho Valev wrote:
Journalists believe Newton can also bend light:

http://blogs.nature.com/news/blog/2007/09/arthur_eddington_was_innocent.html
Journalists: "And contrary to popular belief, Newtonian physics did
not predict that light would remain undeflected – Einstein himself
pointed out in 1911 that Newtonian gravity should cause some deviation
too."

Who is right: Lee Smolin ("popular belief") or journalists?

The journalists are right.

Journalists have a culture of trying to check facts all the way back
to their primary sources: physicists sometimes have a bad habit of
simply believing and repeating what they were taught by their elders.

The physics community tends to be a firm believer in the merits of
peer review, and if something is generally taught and believed within
their community, physicists will often tend to reckon that the thing
//must// be true because somebody somewhere //must// have checked it.
They also tend to reckon that if a thing is checked and found to be
wrong, that the correction will propagate speedily through the
community, and the bad information will be extinguished.

Unfortunately, it doesn't always work like that.
The more strongly that people believe the system already works really
well, the easier it is for that system to go badly wrong: People don't
check facts because they think that "someone else" will have done it,
and when corrections appear they're sometimes dismissed and
disbelieved on the basis that the correction can't possibly be right,
because it conflicts with what a physicist was taught.

When a piece of bad mythology takes hold in the physics community it
can take decades to root it out. Sometimes longer. A thing
//nominally// gets corrected, but you find that some lecturers are
still teaching the older "bad" version forty years after the
correction is supposed to have reached everybody.



Quote:
Let's not forget that during Newton's time, the speed of light was not
known, and was considered to be infinite.

No, I'm afraid that's at odds with the contemporary historical record.
Get hold of copies of "Principia" and "Opticks" and do a bit of
skimming. Newton draws diagrams of light bending around objects, and
light bending at a lightspeed boundary, and in Opticks he tries to
describe the action of a gravitational field on bodies as the effect
of a lightspeed variation associated with the gravitational field.
Basically he associates the concentration of mass with a variation in
the density of a background medium, associates that density-variation
with a lightspeed-variation, and from there he suggests that the thing
that we know of as gravity is the result of the "refraction" of bodies
by the lightspeed differential.

He also explains that the speed of light is known to be finite, thanks
to astronomical measurements of the apparent eclipse times of the
moons of Jupiter, and says that it takes light several minutes to
reach the Earth from the Sun.



Don't believe what you're told about physics and physics history in
school, college or university without actually checking the stuff out
yourself. At lot of it is factually wrong, with the highest
concentration of "junk" facts seeming to cluster around anything to do
with special relativity, how special relativity compares to earlier
theories, or the testing of special relativity.

Just because the person telling you something is a professor, it
doesn't mean that you can't disprove what they're telling you with a
bit of trig, or half an hour judiciously spent at the local science
library. Professors are busy people. They often don't have time to
spend weeks combing through their university's library, fact-checking
all the bad things that they and their colleagues were taught back
when they were fifteen.

If they're telling you something that they can prove or demonstrate,
then fair enough. If they're telling you something that's supposed to
be true because everyone //knows// that it's true, and because it's in
the physics textbooks, and because everyone who knows the subject
supposedly agrees ... reserve judgment.



Quote:
A finite lightspeed of 300,000
kps (186,000 mps) would still be deflected by Newtonian gravity, but an
infinite lightspeed would not be deflected by anything.

Yousuf Khan


=Erk= (Eric Baird)
: Deep-fried strawberries! http://www.youtube.com/user/ErkDemon
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Androcles...
Posted: Thu Jun 26, 2008 3:35 pm
Guest
<Eric Baird> wrote in message
news:gdl764tdqn3sbea0d053ved3j83dka8hs4 at (no spam) 4ax.com...
| On Fri, 20 Jun 2008 22:12:15 -0400, Yousuf Khan <bbbl67 at (no spam) yahoo.com>
| wrote:
|
| >Pentcho Valev wrote:
| >> Journalists believe Newton can also bend light:
| >>
| >>
http://blogs.nature.com/news/blog/2007/09/arthur_eddington_was_innocent.html
| >> Journalists: "And contrary to popular belief, Newtonian physics did
| >> not predict that light would remain undeflected - Einstein himself
| >> pointed out in 1911 that Newtonian gravity should cause some deviation
| >> too."
| >>
| >> Who is right: Lee Smolin ("popular belief") or journalists?
|
| The journalists are right.
|
| Journalists have a culture of trying to check facts all the way back
| to their primary sources: physicists sometimes have a bad habit of
| simply believing and repeating what they were taught by their elders.
|
| The physics community tends to be a firm believer in the merits of
| peer review, and if something is generally taught and believed within
| their community, physicists will often tend to reckon that the thing
| //must// be true because somebody somewhere //must// have checked it.
| They also tend to reckon that if a thing is checked and found to be
| wrong, that the correction will propagate speedily through the
| community, and the bad information will be extinguished.
|
| Unfortunately, it doesn't always work like that.
| The more strongly that people believe the system already works really
| well, the easier it is for that system to go badly wrong: People don't
| check facts because they think that "someone else" will have done it,
| and when corrections appear they're sometimes dismissed and
| disbelieved on the basis that the correction can't possibly be right,
| because it conflicts with what a physicist was taught.
|
| When a piece of bad mythology takes hold in the physics community it
| can take decades to root it out. Sometimes longer. A thing
| //nominally// gets corrected, but you find that some lecturers are
| still teaching the older "bad" version forty years after the
| correction is supposed to have reached everybody.
|
|
|
| >Let's not forget that during Newton's time, the speed of light was not
| >known, and was considered to be infinite.
|
| No, I'm afraid that's at odds with the contemporary historical record.
| Get hold of copies of "Principia" and "Opticks" and do a bit of
| skimming. Newton draws diagrams of light bending around objects, and
| light bending at a lightspeed boundary, and in Opticks he tries to
| describe the action of a gravitational field on bodies as the effect
| of a lightspeed variation associated with the gravitational field.
| Basically he associates the concentration of mass with a variation in
| the density of a background medium, associates that density-variation
| with a lightspeed-variation, and from there he suggests that the thing
| that we know of as gravity is the result of the "refraction" of bodies
| by the lightspeed differential.
|
| He also explains that the speed of light is known to be finite, thanks
| to astronomical measurements of the apparent eclipse times of the
| moons of Jupiter, and says that it takes light several minutes to
| reach the Earth from the Sun.
|
|
|
| Don't believe what you're told about physics and physics history in
| school, college or university without actually checking the stuff out
| yourself. At lot of it is factually wrong, with the highest
| concentration of "junk" facts seeming to cluster around anything to do
| with special relativity, how special relativity compares to earlier
| theories, or the testing of special relativity.
|
| Just because the person telling you something is a professor, it
| doesn't mean that you can't disprove what they're telling you with a
| bit of trig, or half an hour judiciously spent at the local science
| library. Professors are busy people. They often don't have time to
| spend weeks combing through their university's library, fact-checking
| all the bad things that they and their colleagues were taught back
| when they were fifteen.
|
| If they're telling you something that they can prove or demonstrate,
| then fair enough. If they're telling you something that's supposed to
| be true because everyone //knows// that it's true, and because it's in
| the physics textbooks, and because everyone who knows the subject
| supposedly agrees ... reserve judgment.
|
|
|
| >A finite lightspeed of 300,000
| >kps (186,000 mps) would still be deflected by Newtonian gravity, but an
| >infinite lightspeed would not be deflected by anything.
| >
| > Yousuf Khan
|
|
| =Erk= (Eric Baird)
| : Deep-fried strawberries! http://www.youtube.com/user/ErkDemon

I endorse your comments, Eric. You are quite correct.
Nice fractal, BTW. What algorithm did you use?

--
Androcles, proud to be as British as Baldric.
http://www.androcles01.pwp.blueyonder.co.uk/MagnaCarta.wmv
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Androcles...
Posted: Thu Jun 26, 2008 7:02 pm
Guest
"xxein" <xxein1 at (no spam) bellsouth.net> wrote in message
news:4fbde41d-fdfe-4e11-b6ac-06a27d2ce48f at (no spam) f63g2000hsf.googlegroups.com...
On Jun 21, 7:53 pm, Pentcho Valev <pva... at (no spam) yahoo.com> wrote:
Quote:
On Jun 22, 12:52 am,xxein<xxe... at (no spam) bellsouth.net> wrote:





On Jun 20, 2:46 am, Pentcho Valev <pva... at (no spam) yahoo.com> wrote:

On Jun 20, 5:16 am,xxein<xxe... at (no spam) bellsouth.net> wrote:

On Jun 19, 7:32 pm, Pentcho Valev <pva... at (no spam) yahoo.com> wrote:

http://streamer.perimeterinstitute.ca/mediasite/viewer/NoPopupRedirec...
Lee Smolin: "Newton's theory predicts that light goes in straight
lines and therefore if the star passes behind the sun, we can't
see
it. Einstein's theory predicts that light is bent...."

Pentcho Valev
pva... at (no spam) yahoo.com

xxein: What about it? Do you have a question?

Journalists believe Newton can also bend light:

http://blogs.nature.com/news/blog/2007/09/arthur_eddington_was_innoce...
Journalists: "And contrary to popular belief, Newtonian physics did
not predict that light would remain undeflected – Einstein himself
pointed out in 1911 that Newtonian gravity should cause some deviation
too."

Who is right: Lee Smolin ("popular belief") or journalists?

Pentcho Valev
pva... at (no spam) yahoo.com

xxein: Who cares as long as we eventually get the physic right?

xxein: Who cares? I hate to say it in this way because I am such a
critic of present science theory, but the fact that light bends in
gravity is irrefutable. But I have never seen it described correctly.

Einstein described it correctly in 1911 when he deduced the equation
c'=c(1+V/c^2) showing how the speed of light varies with the
gravitational potential V. This equation is incompatible with
Einstein's 1905 light postulate (c'=c) and compatible with (more
precisely, equivalent to) the equation c'=c+v given by Newton's
emission theory of light.

Pentcho Valev
pva... at (no spam) yahoo.com



I have done a ton of work on this. No one has even has a clue as to
what physically happens to bent light and the reference time
associated to it for observational frames.

It is simple and complete, but nobody seems to catch on. Maybe
because I haven't presented it yet?

I know you read a lot and are not very satisfied with the present
physic as we think we know it. Have you ever stepped back far enough
to re-analyze it? There is a certain point like somewhere between
alchemy and chemistry that can give a good starting point to be able
to re-analyze that science. The same with any other or physical
knowledge in general. Try it for a few years. If you are any good at
logic, you will find that all is rotten (in Denmark).

It's not that hard to find info enough to make a rational
investigation and find the physical logic. I did it before the
Internet. That should say something because I am here now and still
find no rational argument or theory that can circumvent or alter the
behavior of the physic as I saw/see it.

If you buy the argument that guesses are all we have and that some
work better than others, then there is where I am at.

I will not and cannot lie to you. I can't figure out how to connect
the observations of QM to GR. QM shows no recognition of gravity. GR
has no interface with QM. We can think on terms of one or the other,
each missing components the other.

I'm not doing a half-bad job of making that connection. I can connect
a gravity between them and give reason, but not much else for detail.
Not that reason and logic should be sloughed off here, but there is a
lot we haven't examined and what we already have examined comes with a
preconceived baggage of interpretation. Iow, what the public is
presented with is basically the resultant conclusion of the data ---
not raw data.

Perhaps another way of saying all of the above will be more
convincing.

I can use a different notion of the physic and get the same results as
GPS. The end result is the same. But I used the objective form of
the physic and then translated it into the common subjective form for
our observation. A completely different process that can separate the
objective physic from the subjective observance of it.

I shouldn't be able to do this if our present theories were the only
answer. This shows that we can math manipulate theories all we want
to get the correct subjectively measured result.

But more importantly, GR was supposed to simplify the matter.
Instead, it ended up in a quagmire of math with no clear physic as an
answer (except for self-generated math to try to keep up with
subjective observation).

Do you understand?- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -

xxein: V or v does not relate to a non-linear gravitational function
as presented by you. Don't get stupid. You should know better.
===========================================

Yes, he should learn all about artefactual/superficially imposed yin-yangs
of sorts, right?
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Androcles...
Posted: Sun Jul 06, 2008 10:22 pm
Guest
<Eric Baird> wrote in message
news:dhj27490s997vse8l906pke0u19fvrmv8n at (no spam) 4ax.com...
| On Thu, 26 Jun 2008 21:35:06 +0100, "Androcles"
| <Headmaster at (no spam) Hogwarts.physics> wrote:
|
| >
| ><Eric Baird> wrote in message
| >news:gdl764tdqn3sbea0d053ved3j83dka8hs4 at (no spam) 4ax.com...
|
| ... SNIPP
|
| >| If they're telling you something that they can prove or demonstrate,
| >| then fair enough. If they're telling you something that's supposed to
| >| be true because everyone //knows// that it's true, and because it's in
| >| the physics textbooks, and because everyone who knows the subject
| >| supposedly agrees ... reserve judgment.
| >|
| >|
| >| =Erk= (Eric Baird)
| >| : Deep-fried strawberries! http://www.youtube.com/user/ErkDemon
| >
| >I endorse your comments, Eric. You are quite correct.
|
| Cool.
|
| PS: I don't want people to think I'm being specifically negative about
| Smolin, because I think he's okay.
|
| IMO, he didn't say anything //unusually// wrong, he just trotted out
| the same bad view of physics history that he was probably taught to
| him when he was wee, and which has probably been repeated in
| innumerable classrooms and lecture halls all over the planet, for
| generations now.
|
| He was just unfortunate enough to have a camera on him when he said
| it.
|
| Smile
|
|
|
|
| >Nice fractal, BTW. What algorithm did you use?
|
| You mean, the stuff at http://www.youtube.com/user/ErkDemon ?
|
| :To make the "Tricorn" fractal:
| Take a bog-standard Mandelbrot algorithm and just insert a minus sign
| in the line of code that deals with the imaginary component. That
| flips the Mandelbrot set into the "Mandelbar" set (aka the "Tricorn").
| http://en.wikipedia.org/wiki/Mandelbar
|
|
| :To make that odd fractal solid:
| Take the same standard Mandelbrot algorithm (X real, Y imaginary) and
| add an additional imaginary component for the Z-axis. Check that the
| Y-axis and Z-axis code is equivalent, and try a few different slices
| and animations to make sure that the code successfully generates the
| shape of a Mandelbrot set spun about its axis (which itself isn't very
| interesting).
| Then add a minus sign (as before) to the code for //one// of the two
| imaginary axes. You then have a solid that generates a Mandelbrot set
| cross-section on one plane, and a Tricorn fractal cross-section on
| another plane at right angles to it.
|
| I was going to do a high-definition version (1600*1080, ~1000
| variable-transparency slices per frame), but I figured that YouTube
| would probably compress it to hell, so in the end I only uploaded a
| 320*240, 300-slice 360-frame version. Even so, that seems to come to
| over a hundred thousand individual component images . Smile
|
| There are some more Tricorn and 3D images at
| http://www.relativitybook.com/CoolStuff/erkfractals.html
| and
| http://www.relativitybook.com/CoolStuff/erkfractals_3d.html
|


Some years ago (1990) I was fooling around with 640 * 480 pixel
256 colour Mandelbrot subset images with a Lorenz butterfly attractor
http://en.wikipedia.org/wiki/Lorenz_attractor
controlling a continuous tone RGB palette.
http://en.wikipedia.org/wiki/List_of_palettes#RGB_arrangements

(Imagine the parrot as a Mandelbrot subset)

Quite easy to do, the X, Y and Z components of the attractor
corresponded with appropriate scaling to red, green and blue,
and so I had a slowly evolving display.

What I was looking for was to project a colour changing Mandelbrot
onto a surface for a discotheque application, so I photographed my
computer screen to create slides for a projector.

Well, I didn't get much further, my girlfriend at the time took the images
and had them blown up, framed them and sold them as art.
Since she was a good salesperson it was quite a lucrative business for
a while, she was getting on average $1,000 a picture with three or four
sales a week.

I also made some n-root images based on an iterative

sqrt(x) = 1/2 [x/sqrt(x) + sqrt(x)]

which can be extended to

n_root(x) = 1/n [ x/n_root(x) + (n-1)* n_root(x) ]

where x is a complex number and the colour index into the palette is the
number of iterations needed to converge.

Seems to me that if you did create a high-definition version and then
applied standard rotation and translation to the model (as with Google
Sketchup, Flight Simulator, city builder games etc...) you'd have some
neat stuff. I wouldn't choose a YouTube limitation as a standard, that
will not remain current.
When I was creating images I was using a 12 MHz '286 processor,
much to slow for what I really wanted to do.

Newton does bend light, as shown here:
http://www.androcles01.pwp.blueyonder.co.uk/FrameA.gif
http://www.androcles01.pwp.blueyonder.co.uk/FrameB.gif

A straight universal path is a curved path in the frame of the Earth
orbiting the Sun.
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