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| Marvin Barley... |
 Posted: Sun Nov 01, 2009 10:11 pm |
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Let's go back to the twin paradox ...
Two twins. One speeds up to 0.99 c and the other remains on Earth.
After going to Alpha Centauri and back - the traveling twin finds out
his twin brother advanced in age, I will not calculate how much
exactly now.
Uh - oh.
Everything is relative. So it is impossible to say which system is the
reference system. But only one brother ages faster? How to explain
that. But I've covered this one previously, and the challenge was
unmet with evidence.
Everything is relative. Yet, only one twin brother experiences
acceleration/deceleration, getting glued to his chair in the space
vessel from multiple Gs. While he is experiencing his body to grow in
weight to 300 kg, he feels pretty well which system is accelerating,
and which isn't. Right?
Is everything so relative?
Maybe spacetime has "memory" over what accelerated and what didn't,
providing the means for twin paradox to occur?
Perhaps then it is possible to find a non-moving point and speed in
the Universe? |
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| jbriggs444... |
| Posted: Mon Nov 02, 2009 2:52 am |
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On Nov 2, 3:11 am, Marvin Barley <mtodorov3... at (no spam) yahoo.com> wrote:
[quote]Let's go back to the twin paradox ...
Two twins. One speeds up to 0.99 c and the other remains on Earth.
After going to Alpha Centauri and back - the traveling twin finds out
his twin brother advanced in age, I will not calculate how much
exactly now.
Uh - oh.
Everything is relative. So it is impossible to say which system is the
reference system.
[/quote]
"Everything is relative" is not a correct synopsis of the theory of
relativity. Furthermore, there is a difference between "inertial
frame of reference" and "reference system".
Let's start with the second part and work back to the first.
A frame of reference is a standard for being at rest. It can be
thought of as a coordinate system with an x, y and z axis in space and
a t axis for time.
You can tie the origin of the coordinate system to an object so that
the object is always at the point where x=y=z=0. In such a coordinate
system, the chosen object is always at rest. But if the object is a
rocket whose thrusters are firing, the coordinate system in which the
rocket is at rest will not be _inertial_. Such a frame is called an
"accelerating frame of referrence" as opposed to an "inertial frame of
reference". With respect to an accelerating frame of reference,
objects that are not subject to external forces will be observed to
accelerate
The principle of relativity says that in any _inertial_ frame of
reference (i.e. a frame in which Newton's laws hold good), all the
laws of physics will work identically.
You can analyze the twin's paradox from any inertial frame you like.
It doesn't even have to be a frame tied to one of the objects in the
twin's scenario.
What you're not allowed to do is choose a frame of reference tied to
the travelling twin and pretend that the laws of physics still hold
good in this frame. The frame of reference tied to this trajectory is
not inertial. |
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| Igor... |
| Posted: Mon Nov 02, 2009 4:46 am |
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On Nov 2, 3:11 am, Marvin Barley <mtodorov3... at (no spam) yahoo.com> wrote:
[quote]Let's go back to the twin paradox ...
Two twins. One speeds up to 0.99 c and the other remains on Earth.
After going to Alpha Centauri and back - the traveling twin finds out
his twin brother advanced in age, I will not calculate how much
exactly now.
Uh - oh.
Everything is relative. So it is impossible to say which system is the
reference system. But only one brother ages faster? How to explain
that. But I've covered this one previously, and the challenge was
unmet with evidence.
Everything is relative. Yet, only one twin brother experiences
acceleration/deceleration, getting glued to his chair in the space
vessel from multiple Gs. While he is experiencing his body to grow in
weight to 300 kg, he feels pretty well which system is accelerating,
and which isn't. Right?
Is everything so relative?
Maybe spacetime has "memory" over what accelerated and what didn't,
providing the means for twin paradox to occur?
Perhaps then it is possible to find a non-moving point and speed in
the Universe?
[/quote]
The twin paradox is easily resolved by analyzing which twin has the
longer path through spacetime. And as far as your statement that
everything is relative, it just ain't so, even in relativity. |
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| PD... |
| Posted: Mon Nov 02, 2009 7:56 am |
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On Nov 2, 2:11 am, Marvin Barley <mtodorov3... at (no spam) yahoo.com> wrote:
[quote]Let's go back to the twin paradox ...
Two twins. One speeds up to 0.99 c and the other remains on Earth.
After going to Alpha Centauri and back - the traveling twin finds out
his twin brother advanced in age, I will not calculate how much
exactly now.
Uh - oh.
Everything is relative. So it is impossible to say which system is the
reference system.
[/quote]
No, relativity does NOT say this. This is precisely the point of the
teaching puzzle, is to illustrate that applying such oversimplistic
statements will get you in trouble really quick.
[quote]But only one brother ages faster? How to explain
that. But I've covered this one previously, and the challenge was
unmet with evidence.
Everything is relative. Yet, only one twin brother experiences
acceleration/deceleration, getting glued to his chair in the space
vessel from multiple Gs. While he is experiencing his body to grow in
weight to 300 kg, he feels pretty well which system is accelerating,
and which isn't. Right?
Is everything so relative?
Maybe spacetime has "memory" over what accelerated and what didn't,
providing the means for twin paradox to occur?
Perhaps then it is possible to find a non-moving point and speed in
the Universe?[/quote] |
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| Sam Wormley... |
| Posted: Mon Nov 02, 2009 12:31 pm |
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Guest
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Marvin Barley wrote:
[quote]Let's go back to the twin paradox ...
Two twins. One speeds up to 0.99 c and the other remains on Earth.
After going to Alpha Centauri and back - the traveling twin finds out
his twin brother advanced in age, I will not calculate how much
exactly now.
Uh - oh.
Everything is relative. So it is impossible to say which system is the
reference system. But only one brother ages faster? How to explain
that. But I've covered this one previously, and the challenge was
unmet with evidence.
[/quote]
Which brother experienced acceleration?
Which did not?
Physics FAQ: The Twin Paradox
http://math.ucr.edu/home/baez/physics/Relativity/SR/TwinParadox/twin_paradox.html |
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| Uncle Al... |
| Posted: Tue Nov 03, 2009 12:02 am |
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Marvin Barley wrote:
[quote]
Let's go back to the twin paradox ...
[/quote]
1) Twin Paradox
http://www.hawaii.edu/suremath/SRtwinParadox.html
http://sheol.org/throopw/sr-twin-01.html
<http://physics.syr.edu/courses/modules/LIGHTCONE/twins.html>
2) idiot
[quote]Two twins. One speeds up to 0.99 c and the other remains on Earth.
After going to Alpha Centauri and back - the traveling twin finds out
his twin brother advanced in age, I will not calculate how much
exactly now.
Uh - oh.
Everything is relative. So it is impossible to say which system is the
reference system. But only one brother ages faster? How to explain
that. But I've covered this one previously, and the challenge was
unmet with evidence.
[/quote]
1) The twin that traverses the most space accumulates the least
time. The foru-vector is conserved.
2) idiot
[quote]Everything is relative. Yet, only one twin brother experiences
acceleration/deceleration, getting glued to his chair in the space
vessel from multiple Gs. While he is experiencing his body to grow in
weight to 300 kg, he feels pretty well which system is accelerating,
and which isn't. Right?
Is everything so relative?
[/quote]
Acceleration is irrelevant.
[In the Newtonian approximation to GR, the line element for "Newtonian
coordinates" is to excellent approximation:
ds^2 = -(1 - 2\phi) dt^2 + dx^2 + dy^2 + dz^2
where \phi is the Newtonian gravitational potential, c=1
The only deviation from Minkowski spacetime is in the time coordinate
- using these coordinates the 3-space corresponding to a given value
of t is Euclidean flat.]
Twin Paradox: One twin travels relativistically, one twin stays
home. They reunite. The traveling twin aged much less. The twin who
travels through more space accumulates less time; also true for an
orbit. Interval sqrt(t^2 - x^2 - y^2 - z^2) between the two events,
expressed in inertial coordinate system (t,x,y,z), is conserved.
Given the invariant interval, the larger sqrt(x^2 + y^2 + z^2) is the
smaller sqrt(t^2) must be.
The ratio by which the two aged when they are again local is identical
in all reference frames: ratio = sqrt(t^2 - x^2 - y^2 - z^2)/t (units
of c=1).
Acceleration is irrelevant, demonstrated by Triplets.
Three identical clocks as kits and not constructed until the
experiment is running. Each clock has a short toggle switch.
Individual spaceships carry a kit each. Set up the experiment.
CLOCK 1: Our clock sits stationary in our inertial reference frame
with its toggle sticking out. Touch the toggle and "off" state goes
"on" or "on" state goes "off." Build it from parts just before
needed, in the "off" state, zeroed.
CLOCK 2: In a spaceship traveling at 0.999c relative to our inertial
frame and positioned far to our left. Clock 2 was built after all
acceleration ceased during setup, set to zero, "off" state. It skims
past Clock 1 (our clock) in vacuum free fall, toggles touch, both
Clocks 1 and 2 are "on" and locally synchronized by touching. Elapsed
time accumulates in each clock.
CLOCK 3: In a spaceship traveling at 0.999c relative to our inertial
frame of reference, but 180 degrees counter in direction to Clock 2,
far far to our right. It was built after all acceleration ceased
during setup, set to zero, "off" state.
An arbitrary time after Clocks 1 and 2 synchronize and turn "on" by
touching, Clocks 2 and 3 brush past each other, both in vacuum free
fall, touching toggles. Clock 2 is now "off," Clock 3 is now "on."
Write down the elapsed time in "off" Clock 2. The spaceship with
Clock 3 returns over the path taken by the spaceship with Clock 2.
CLOCK 1: Our clock. It sits stationary in our inertial reference
frame with a little toggle sticking out. Clock 3 vacuum free falls
past, toggles touch. Clocks 3 and 1 are off. Write down elapsed
times. No clock accelerated while "on" or while existing.
BOTTOM LINE: Send results by radio. Numbers on paper don't change.
Throughout the entire run three clocks were passive observers in
vacuum free fall with zero acceleration.
Compare elapsed times. Elapsed times #2+#3 does not equal #1, the
local stationary reference frame summation. The sum of #2+#3 elapsed
time is about 4.5% that than of #1's accumulated elapsed time. The
Twin (Triplets) Paradox obtains without any clock having been
accelerated.
[quote]Maybe spacetime has "memory" over what accelerated and what didn't,
providing the means for twin paradox to occur?
Perhaps then it is possible to find a non-moving point and speed in
the Universe?
[/quote]
idiot
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz4.htm |
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| zzbunker at (no spam) netscape.net... |
| Posted: Tue Nov 03, 2009 5:34 am |
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On Nov 2, 3:11 am, Marvin Barley <mtodorov3... at (no spam) yahoo.com> wrote:
[quote]Let's go back to the twin paradox ...
Two twins. One speeds up to 0.99 c and the other remains on Earth.
After going to Alpha Centauri and back - the traveling twin finds out
his twin brother advanced in age, I will not calculate how much
exactly now.
Uh - oh.
Everything is relative. So it is impossible to say which system is the
reference system. But only one brother ages faster? How to explain
that. But I've covered this one previously, and the challenge was
unmet with evidence.
Everything is relative. Yet, only one twin brother experiences
acceleration/deceleration, getting glued to his chair in the space
vessel from multiple Gs. While he is experiencing his body to grow in
weight to 300 kg, he feels pretty well which system is accelerating,
and which isn't. Right?
Is everything so relative?
[/quote]
In thought experiments everything is relative.
Which is also why the people who understand science, history,
speeds and velocity and
the crank Hamilitonians of Quantum Mechanics even work on 1, 2,, 3,
and 4D Holographics,
Desktop Publishing, On-Line Publishing, Drones, Biodiesel,
Diigital Books, Pv Cell Energy,
Rapid Prototyping, CD, DVD, Home Broadband, Microwave Cooling,
Thermo-Electric Cooling,
Reverse Compilers, Post GM-nomics, and the 21st Century, rather
than with idiot physicists
and mu-on accelerators,
And Multiplexed Fiber Optics, HDTV, GPS, Weather Satellites, Data
Fusion, Digital Terrain Mapping,
UAVs, Atomic Clock Wristwatches, Light Sticks, and Blue Ray rather
than
with NASA and the Turing Machine Hypersphereians.
And Compact Flourescent Lighting, Cyber Batteries, USB, All-IIn-One
Printers,
Content Addressable Memory, Self-Assembling Robots, Self-
Replicating Machines,
Flat Sceen Debuggers, Post 1960 Cell Phones, and Laser-Guided
Phasors,
rather than with IBM Prom Cranks.
And mp3, mpeg, Post ACME Screwthreads, Flash Memory, Distributed
Processing Software,
and Bi-Optical Computers,
rather than with GE wanks and Optical Computer Patents,
[quote]
Maybe spacetime has "memory" over what accelerated and what didn't,
providing the means for twin paradox to occur?
Perhaps then it is possible to find a non-moving point and speed in
the Universe?[/quote] |
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| G=EMC^2 Glazier... |
| Posted: Tue Nov 03, 2009 9:02 am |
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Sam Macro realm things can go well with relativity(it fits) In micro
quantum realm relativity does not relate. That makes our brains getting
dizzy thinking QM. So we have great thinkers like Feynman saying "QM is
weird: or Bohr telling us no one after studying QM can say they
understand it. Bert |
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| G=EMC^2 Glazier... |
| Posted: Tue Nov 03, 2009 9:06 am |
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Uncle Al (of Irvine) Best never to forget twin going at close to c gets
no work done(no sex) this proves there is no free lunch go figure Bert |
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| Sam Wormley... |
| Posted: Tue Nov 03, 2009 1:22 pm |
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G=EMC^2 Glazier wrote:
[quote]Sam Macro realm things can go well with relativity(it fits) In micro
quantum realm relativity does not relate. That makes our brains getting
dizzy thinking QM. So we have great thinkers like Feynman saying "QM is
weird: or Bohr telling us no one after studying QM can say they
understand it. Bert
[/quote]
Quantum Electrodynamics (QED) is the relativistic quantum field theory
of electrodynamics, Herb. So quantum realm relativity DOES relate, even
if YOU say it doesn't. |
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| G=EMC^2 Glazier... |
| Posted: Tue Nov 03, 2009 5:38 pm |
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Sam Again please read my post. I never mentioned my thoughts,but you put
me in first position. I have posted over many moons QM is humankinds
greatest theory. I in my humble,but clever brain can get reality out of
the quantum realm. Bert |
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| Aleph... |
| Posted: Wed Nov 04, 2009 8:13 am |
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On Wednesday 04 November 2009 05:44, in
<_ at (no spam) Jeff_Relf.Seattle.2009_Nov3.9.46pm.72>, _ at (no spam) Jeff_Relf.Seattle.inValid sat
down and wrote:
[quote]
Semi-Randomness is imprecise measurement, nothing more.
General Relativity is just a model,
one that requires non-random inputs.
[/quote]
So many words, so little knowledge.
--
Aleph
This message was posted to usenet so please reply that way. Emails to
this account are very likely to be ignored. |
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| G=EMC^2 Glazier... |
| Posted: Thu Nov 05, 2009 8:17 am |
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To ya all Relativity is not relative in the quantum micro realm world.
Einstein knew that immediately. He went against QM for that very reason.
Bohr realized this and it pissed him off. When Einstein said "God does
not play dice" Bohr came back with. "Einstein is now telling us what
God does" bert |
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| Sam Wormley... |
| Posted: Thu Nov 05, 2009 9:25 am |
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G=EMC^2 Glazier wrote:
[quote]To ya all Relativity is not relative in the quantum micro realm world.
Einstein knew that immediately. He went against QM for that very reason.
Bohr realized this and it pissed him off. When Einstein said "God does
not play dice" Bohr came back with. "Einstein is now telling us what
God does" bert
Quantum Electrodynamics (QED) is the relativistic quantum field theory[/quote]
of electrodynamics, Herb. |
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