Special relativity from first principles
December 19, 2011 By Steve Nerlich, Universe Today
There's hope for us all if a mild-mannered patent office clerk can become Person Of The 20th Century.
Einsteins explanation of special relativity, delivered in his 1905 paper On the Electrodynamics of Moving Bodies focuses on demolishing the idea of absolute rest, exemplified by the theoretical luminiferous aether. He achieved this very successfully, but many hearing that argument today are left puzzled as to why everything seems to depend upon the speed of light in a vacuum.
Since few people in the 21st century need convincing that the luminiferous aether does not exist, it is possible to come at the concept of special relativity in a different way and just through an exercise of logic deduce that the universe must have an absolute speed and from there deduce special relativity as a logical consequence.
The argument goes like this:
1) There must be an absolute speed in any universe since speed is a measure of distance moved over time. Increasing your speed means you reduce your travel time between a distance A to B. At least theoretically you should be able to increase your speed up to the point where that travel time declines to zero and whatever speed you are at when that happens will represent the universes absolute speed.
2) Now consider the principle of relativity. Einstein talked about trains and platforms to describe different inertial frame of references. So for example, you can measure someone throwing a ball forward at 10 km/hr on the platform. But put that someone on the train which is travelling at 60 km/hr and then the ball measurably moves forward at nearly 70 km/hr (relative to the platform).
3) Point 2 is a big problem for a universe that has an absolute speed (see Point 1). For example, if you had an instrument that projected something forward at the absolute speed of the universe and then put that instrument on the train you would expect to be able to measure something moving at the absolute speed + 60 km/hr.
4) Einstein deduced that when you observe something moving at the absolute speed in a different frame of reference to your own, the components of speed (i.e. distance and time), must change in that other frame of reference to ensure that anything moving at the absolute speed can never be measured moving at a speed greater than the absolute speed.
Thus on the train, distances should contract and time should dilate (since time is the denominator of distance over time).
The effect of relative motion. Measurable time dilation is negligible on a train moving past a platform at 60 km/hr, but increases dramatically if that train acquires the capacity to approach the speed of light. Time (and distance) will change to ensure that light speed is always light speed, not light speed + the speed of the train.
And thats it really. From there one can just look to the universe for examples of something that always moves at the same speed regardless of frame of reference. When you find that something, you will know that it must be moving at the absolute speed.
Einstein offers two examples in the opening paragraphs of On the Electrodynamics of Moving Bodies:
-- the electromagnetic output produced by the relative motion of a magnet and an induction coil is the same whether the magnet is moved or whether the coil is moved (a finding of James Clerk Maxwells electromagnetic theory) and;
-- the failure to demonstrate that the motion of the Earth adds any additional speed to a light beam moving ahead of the Earths orbital trajectory (presumably an oblique reference to the 1887 Michelson-Morley experiment).
In other words, electromagnetic radiation (i.e. light) demonstrated the very property that would be expected of something which moved at the absolute speed that it is possible to move in our universe.
The fact that light happens to move at the absolute speed of the universe is useful to know since we can measure the speed of light and hence we can then assign a numerical value to the universes absolute speed (i.e. 300,000 km/sec), rather than just calling it c.
More information: None! That was AWAT #100 more than enough for anyone. Thanks for reading, even if it was just today. SN.
Source: Universe Today
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Dec 19, 2011
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Dec 19, 2011
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First of all THE Person of the 20th Century was awarded to Einstein by Time Mag in `99 !!!
2ndly, PhysOrg should consult its own arxiv prior to running articles from weak mags like UT which make `amazing claims', that are actually well documented history
http://www.physor...100.html
Dec 19, 2011
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Dec 19, 2011
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Although referred to as "failed" experiments to demonstrate the concept of aether, the experiments actually make sense if you consider that the Earth is actually stationary in the universe. A supposedly ridiculous notion but theoretically possible when the entire universe's stars are taken into account as having a cumulative gravitational effect. Which has also been proven in other experiments.
And, a dense aether medium at Planck scale into which the entire universe is embedded also gives many other explanations to "mysteries". It can be shown that this medium which some theorists describe as superstrings accounts for the universe without the need for "dark matter".
Dec 19, 2011
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Dec 19, 2011
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In the piece-wise defined, psuedo-vector space of relativity, distance equals zero when velocity equals "c" because of length contraction.
0 = sqrt(1 - (v^2/c^2)), when "v" = "c".
therefore, contrary to the popular understanding of Relativity, it does NOT take a year to travel a light-year at the speed of light.
Light crosses the entire universe instantaneously, because in the frame of reference of the photon, the distance is zero.
Similarly, a relativistic rocket ship does not require "billions of light years" to cross the universe.
It will actually cross the universe in as little as a few seconds.
Dec 19, 2011
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At 99% of light speed, it becomes 0.141.
At 99.99% it becomes 0.0141..
Etc.
In Relativity theory, travel time approaches a horizontal assymptote of zero as velocity approaches c, because distance approaches zero as velocity approaches c.
Dec 19, 2011
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Dec 19, 2011
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Dec 19, 2011
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Who cares. It contains words like Einstein, relativity, aether - traffic of posters guaranteed.You probably shouldn't confuse aether model with superstring theory. String theorists consider space-time empty and particles as a strings. The idea of stringy environment belongs rather into loop quantum gravity theory.
Dec 19, 2011
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Dec 19, 2011
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But the light waves are transverse (they're polarizable) and the speed of transverse waves doesn't depend on the (speed of) environment at all (after all, in the same way, like the speed of transverse waves in every particle environment).
The silly physicists just confused these two models together. After all, if aether model would be wrong, then Mr. Maxwell couldn't use it for derivation of his equations. But from Maxwell's equations (which are based on the transverse wave model) the constant speed of light follows clearly.
http://www.vttoth...otes/167
How is it possible, the same model can lead into such different predictions?
Dec 19, 2011
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Aether model is actually the only model, which enables to predict/derive the postulate of invariant speed of light from "first geometric principles" instead - the special relativity just conjectures it without any deeper reasoning.
Dec 19, 2011
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IMO this paradox could have two reasons. At first, Maxwell wasn't aware of the concept of the invariance of speed of light too well. This result was derived a way later with Einstein from Maxwell's equations.
At second, at the time of Maxwell only low energy radiowaves and visible light were considered as an electromagnetic waves. In sparse aether a threshold of wavelength must exist, above which the transverse waves are changing into longitudinal ones and the longitudinal waves suffer with aether drag apparently. Because Maxwell didn't know about energetic X-rays and gamma rays, he could believe quite well, the visible light could violate the transverse wave model already, because in his time the visible light represented the upper frequency limit for EM waves.
Dec 19, 2011
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Dec 19, 2011
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But the Sagnac Effect difference should show up in measurements of the measured velocity of light at the equator in the east and west directions. The measurements cannot be the same because of the rotation of the earth. If they were the same than the light would have to travel faster or slow in one direction than the other.
Dec 19, 2011
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Dec 19, 2011
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From article:
Few people need convincing, but some are unconvincible. Right Zephir!
More like, if you make the assumption that there is an absolute speed - from there you can deduce special relativity as a logical consequence. The initial "exercise of logic" is anything but. I guess it got us thinking though.
Dec 19, 2011
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Dec 19, 2011
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Dec 19, 2011
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So this medium accounts for gravitational lensing?
Dec 19, 2011
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http://en.wikiped...vitation
The curvature of light is interpreted like the curvature of space-time in general relativity, but gravity lens exhibit another hyperdimensional phenomena too, like the surface tension.
Dec 19, 2011
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The curvature of light seems to be perfectly capable of explaining gravitational lensing unless I missed something.
Dec 19, 2011
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Dec 19, 2011
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Dec 19, 2011
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It is perfectly logical to assume a universe in which space is absolute (even if it proves difficult to establish one's position or speed) and speed is unbounded and not at all linked to time dilation. From such a starting point, it is not possible to prove by logical deduction alone the existence of an absolute speed. The author is either pulling our leg or really truly stupid.
Dec 19, 2011
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Dec 20, 2011
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Mild mannered? Very bad mannered indeed. A. Einstein was the incorrigible zionist plagiarist of the century and that is my lasting and final opinion.
Dec 20, 2011
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Dec 20, 2011
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Dec 20, 2011
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Time is not dimension of space so X4 is not t, X4 = ict and time t is the numerical sequence of material change, see more on http://physicsess...rized=no
Dec 20, 2011
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This behaviour is easy to understand in two dimensions with using of water surface model. The moving object creates wake wave, which undulates and expands water surface a bit around object. It prolongs the path for another surface ripples, so that they're spreading more slowly around it. The dilatation of water surface is therefore the manifestation of another dimension perpendicular to spatial dimension (surface plane), i.e. like the temporal dimension. This model is consistent with deBroglie wave of quantum mechanics
Dec 20, 2011
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Dec 20, 2011
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Dec 20, 2011
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Particles, however, can get speeds greater than light speed, just as the jets can get speeds greater than sound.
Therefore, CERN scientists will one day discover a gamma ray burst, they had not expected. Then they will detect particles in the accelerator, which speeds greater than light, and they discover that the light barrier has been broken.
Dec 21, 2011
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They detected it already for neutrinos. Your prediction is postdiction.
Dec 21, 2011
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www.amazon.com/Or...06465620
1975 data reported as evidence of super-heavy elements
www.omatumr.com/a...enon.pdf
Convinced Dr. Glenn T. Seaborg to organize the 1999 ACS Symposium, with the Cradle of the Nuclides on the front cover:
Since E = mc^2 and every nucleus is composed of Z
positively charged protons (P) and (A-Z) neutral neutrons (N):
1. Attractive forces between N and P
__ reduce the rest mass when Z /A ~0.5
2. Repulsive forces between N and N
__ increase the rest mass for Z/A <0.5
3. Repulsive forces between P and P
__ increase the rest mass for Z/A >0.5
That explains the ~265 Bohr-Wheeler mass parabolas.
http://arxiv.org/...2.1499v1
Here are individual mass data points:
https://dl-web.dr...8949abdc
Dec 22, 2011
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The neutrinos speed is measured outside the accelerators and a very heavy particle observable, in relation to such protons orbiting in an accelerator.
Neutrinos superluminal velocity is not fully confirmed and are still waiting for the factual documentation.
Dec 22, 2011
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Dec 22, 2011
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Dec 22, 2011
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Actually no it isn't. You are wrong. It is not behaving like an elastic membrane. The observations we attribute to / lead us to Dark matter do not indicate it behaves like "the surface of atmosphere of Earth" (whatever the heck that means).
Surface energy of gravity field? Nonsense.
Behaving like catapult? No. Bad analogy.
Hawking radiation is the "realization" of virtual pairs. The virtual particles borrow energy from the black hole with one side being ejected from near the event horizon and the other being absorbed into the black hole.
I don't understand how you demonstrate such a firm grasp of all of this at times, yet still spout such inconsistent drivel like your last post. Go back and read what you wrote and try not to laugh.
Dec 22, 2011
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You're actually arguing like some fanatic proponent of church or sect, don't you think? If you don't disagree with me in anything without reason, why to express it right here in such complicated way? The usage of downvoting button would be enough.
Dec 22, 2011
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For exampleRational thinking and logical argumentation?
Dec 22, 2011
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http://www.aether...ion3.gif
Dec 22, 2011
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So massive objects like the giant gas planets have a sparse atmosphere?
Dec 23, 2011
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Dec 23, 2011
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IMO they're formed with normal atom nuclei.
Dec 23, 2011
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One of the gravitational charging surrounding a particle, and the second gravitational charging radiates away from the particle.
When two gravitational charging are perpendicular to each other, they will attract each other.
The reason that light is deflected by the gravity field from the Sun, for example, is because light travels in a gravitational field, moving perpendicular to a different gravitational field.
Light wave motion in the gravitational field will most be able to get the speed of light 'c', precisely because the light wave motion happens in the gravitational field.
Dec 23, 2011
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Dec 23, 2011
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It is certainly possible to make testable predictions about gravity, otherwise it would not be possible to calculate the planets circle the sun or an apple drop from a tree.
Of course, the electric force and gravity is not the same. The electric and the magnetic force is also not the same.
The electric and the magnetic force acts perpendicular to each other, therefore the force of gravity could easily have this effect in itself.
This will have the force of gravity on large scale to seem attractive, much more than repulsive. Should gravity work repulsive gravitational fields must be parallel and it happens only when the particles surfaces come close to each other's surfaces.
Dec 23, 2011
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http://en.wikiped...agnetism
Dec 24, 2011
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$255.00 for that book. its official, i've decided, you have lost your mind. over the past year i've been teetering on what thoughts go through your head, now i understand its more like a demolition derby up there.
*sigh*
Dec 26, 2011
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So how did Einstein come out with the testable predictions?