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Thread: can we survive without relativity? is it a worse or a better world, now?

  1. #1 can we survive without relativity? is it a worse or a better world, now? 
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    hallo folks, In a way I have been lucky: I joined this forum because I wanted to understand the necessity of relativity. News from Cern make my quest topical and relevant:

    what is the use of relativity?

    AFAIK it was devised mainly to explain and justify 0) the invariance of C . Now , could you help me and tell me

    1) what problems solved relativity besides this one? are there any?

    2) as regards (0) I never could understand the big surprise about the MM experiment. Why sould speed of light be influenced by the motion of the emitting body?
    being EM radiation, it cannot be influenced by anything, let alone by kinetic energy!

    Thanks for your help


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    Relativity has been tested in numerous different ways and has given the correct answer very accurately in every test I'm aware of (Mercury's orbit and gravitational lensing being the two I can best remember off the top of my head).

    It's not the emitting body, it's the medium carrying light that they thought might be moving. Imagine dropping a stone in a moving stream versus a still pond. The speed of the ripples upstream and downstream would be different. Of course, the speed of the emitting body does make a difference. Look up the Doppler shift, or the relativistic Doppler effect for light in specific.


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    Relativity is the cornerstone of modern physics.I dont think you will find any credible scientist will argue about Einstein's Theories of relativity.The only conclusion is highly probable that CERN have missed some error in their most credible tests.
    The correct approach is to duplicate the experiment at another location.Namely Fermilab,who are indeed in the process of.
    There is another location in Japan,but due to the Tsunami several months ago,are not in a position to test this yet.
    There is an increase of interest about this,which is indeed most welcome.After all,the more people working in Science (all fields),the better i say.
    Theoretically though,kinetic energy is not the issue
    hope this helps
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    Anyone who uses a GPS unit is using relativity. The GPS satellites had to have their internal clocks adjusted for the amount of time-dilation predicted by relativity, otherwise the GPS system wouldn't work properly. Time is relative.
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    I did draw the same conclusion about synchronising the clocks...what about the hard wired feedback ?(presumable fed through a comparitor,to confer the time stamped signal)
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    Michelson and Morley were not looking for a change in speed caused by motion of the emitting body. Because of the apparent wave nature of light, and by analogy to other waves like sound or water waves, they expected light to travel in a medium. This hypothetical medium was called the aether and was presumed to be stationary with respect to some absolute reference frame. No motion with respect to the aether was found. Absence of any detectable motion relative to the aether is evidence for Einstein's theory.

    If light is a particle instead of a wave, then Newton's laws of motion predict that the light from an approaching source should be traveling faster. This is analogous to a projectile's motion from a moving vehicle which goes faster if thrown forward, slower if thrown backwards from the moving vehicle.
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    If only Newton had seen this in the experiments he unknowingly observered, related to duality,he could have founded our current understandings much ealier.Easy to say in hindsight,true...but hard to realise in context...newton is indeed held in high regards
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    Does a fish move to the water if not swimming ? Yes, flying-fish do.
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    Quote Originally Posted by Harold14370 View Post
    .1) No motion with respect to the aether was found. Absence of any detectable motion relative to the aether is evidence for Einstein's theory.
    2)This is analogous to a projectile's motion from a moving vehicle which goes faster if thrown forward,....
    Thanks Harold, as usual you go to the core of the problem

    1) that is the key issue. The concept of aether was unnecessary, because space is the medium, and that is exactly what Einstein did: he called "the aether" space, not explicitly, of course, but he shifted the necessary properties of aether (homogeneity, istropy...) to space, didn't he?

    2) isn't that what you just disproved: a bullet on a train has KE that it sums to the explosion energy, the photon, even if we consider it a particle, has only some properties of a particle, but no KE to be summed.

    so isn't "invariance of C [in any frame]" an obvious postulate? why did we need SR? can you be more specific?

    3) I read in a thread that E=m*C2 is relativity, isn't it an independent issue ascertained before SR by Planck, Wien et al., didn't SR only formalize it?
    4) the same applies to mass-increase, that is related to 3, isn't it foreign to relativity?


    Thanks folks , for your response, please address the individual questions, just put numbers
    Last edited by logic; October 6th, 2011 at 08:04 AM.
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    Logic
    2. When we do calculations using Newton's equations we don't start out with kinetic energy. We start out by treating velocity as a vector, which we sum by vector addition. Then we can calculate kinetic energy. If you think special relativity is obvious, you are a better man than I. I suggest browsing through the relativity primer sticky thread. If you understand that thoroughly, my hat is off to you.
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    Hi Harold, thanks again, probably it was not clear I was not referring to relativity, but to the invariance of C. This, and only this, in my view should be obvious, because speed of light is intrinsic and that is clear from Maxwell. Nothing can influence that, even obscure radiation like gravity can influence frequency and not speed. As to SR I have studied it and I didn't find it difficult, I can't say if I understood it, that's why I am here.

    But only you can assess that. I study logic and I think there might be some flaws, but before I can present any argument to your attention, I need to define, delimit the problem. If you are willing to continue discussion with me I'll be honoured.
    1) is my assumption right? space is considered the medium of propagation of light?
    3)4) these formulas are indepentent of SR?
    0) then, Is the use of SR limited to the invariance of C?, are there arguments against it that force us to use SR?

    2)sorry, I do not see any sum of vectors, I excluded it, I said: a train is speeding at 300 km/h, a shot-bullet has the same kinetic energy, a photon emitted has no kinetic energy to add.
    If
    this assumption is correct, the logic conclusion seems to me ,( if there aren't other reasons I am not aware of, if EMR cannot be influenced even by another radiation) the invariance is obvious
    I'll read the primer and see if it has any answer to my quest

    thanks, everybody

    (note: my opinion is not relevant, but I, too, suppose there might be a trivial mistake of calculation of the distance at CERN)
    Last edited by logic; October 6th, 2011 at 08:06 AM.
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    Logic, I don't really understand the line of reasoning you are taking. What is it you are asking? If C is invariant? or why SR requires it to be?

    1. Space is not regarded as a "medium", that sounds more like ether, a kind of universal reference frame, which there has been 0 evidence discovered in it's favour. SR relates to inertial reference frames relative to other inertial frames, a local theory. GR consists of field equations, which space and time are interlinked as a four dimensional space-time curvature, that includes how mass/energy and gravity affect it. So "space is a medium" means nothing on its own. It is all entwined.
    3-4. I don't understand what you mean

    Photons are massless particles, it really is not an issue for them to move around at C.

    Can you clarify what it is you are asking?
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    Quote Originally Posted by Steiner101 View Post
    1. Space is not regarded as a "medium", that sounds more like ether, 3-4. I don't understand what you mean
    Photons are massless particles, it really b) is not an issue for them to move around at C.
    Thanks steiner,
    I am asking what are the problems that only SR solved or can solve.Why is SR necessary/indispensable.
    3) E = mC is just a formula, (it existed before Einstein and annus mirabilis with different values:3/4...), and it is just a replica of the old E=mv/2
    4) mass increase is just a formula, plots experimental data by extrapolation into the curve of a co(secant)
    (b) you seem to agree) invariance of C is obvious from Maxwell
    all these problems are usually (and probably wrongly) linked with SR

    The only thing related to SR I can see is: Time dilation and space-contraction, and I have a doubt that it might depend on a wrong choice of frame of reference, but we'll discuss THAT when you decide if it is the only problem for which we need SR.
    is my reasoning clear?, I just would like to delimit the problem first, and then move to Time dilation.
    now as to your replies:

    1) space is regarded as a medium in general physics when you ascribe to it properties: such as homogeneity and isotropy,
    space is regarded as a medium in cosmology when you say it expands
    space is regarded as a medium in QM when you talk of quantum foam and "polymers"
    and so on and so forth....

    so I concluded that Einstein was only shrewd and tranferred to space the properties of the medium aether. Is my logic flawed?
    thanks

    (btw: could someone continue discussion on angular momentum?)
    Last edited by logic; October 6th, 2011 at 08:12 AM.
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    Quote Originally Posted by logic View Post
    3) E=mC is just a formula, (it existed before Einstein and annus mirabilis with different values:3/4...), and it is just a replica of the old [B]E=mv/2
    Except that it isn't just a replica of the Newtonian formula of kinetic energy. There is a fairly decent write up of the derivation here: Einstein’s derivation of E=mc^2 What’s new The derivation relies on SR.
    invariance of C is obvious from Maxwell all these problems are usually (and probably wrongly) linked with SR
    It is not clear what we are to do with the speed of light from Maxwell's work alone. It could be that there is a specific system of coordinates in which that speed is measured. We need to develop a different theory of coordinates from that Maxwell used in order to allow the speed of light to be the same in all systems of coordinates.
    1) space is regarded as a medium in general physics when you ascribe to it properties: such as homogeneity and isotropy,
    It may be that these properties are ascribed to the contents of spacetime, given a certain system of coordinates. This is the case in the standard model of cosmology.
    space is regarded as a medium in cosmology when you say it expands
    This is a popular expression, but the models work if we think of the expansion as a change in the relationships between objects.
    space is regarded as a medium in QM when you talk of quantum foam and "polymers" and so on and so forth....
    These are, as yet, speculations not recognized as supported by the available observations and they are not part of QM.
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    Sure, Maxwell's equations say that c is invariant, but Maxwell came 200 yrs after Newton.
    Newton's failing, and the part which you are missing, is the idea of absolute space and absolute time. There is no such thing.
    Relativity, even the special case for inertial frames, is Machian. The space/time metric is determined by the distribution of mass/energy throughout the universe and as such, can change.

    It was the invariance of c AND the dismissal of absolute space and absolute time that showed Einstein's genius.
    Incidentally, the unification of space/time was initially opposed by Einstein, and proposed by Hermann Minkowsky, Einstein's old math professor who, while Einstein was his student , had called him a 'lazy dog'. That is the reason a lot of people assume Einstein was bad at math.
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    Quote Originally Posted by SpeedFreek View Post
    GPS satellites had to have their internal clocks adjusted for the amount of time-dilation predicted by relativity
    Time is relative.
    Hi, speedFreek, could you give some details on that adjustment, its value and why we need it, because of the speed of satellite?
    what is time?
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    Quote Originally Posted by Harold14370 View Post
    Michelson and Morley ... expected light to travel in a medium... . Absence of any detectable motion relative to the aether is evidence for Einstein's theory..
    Quote Originally Posted by Harold14370 View Post
    If you think special relativity is obvious
    I do not think it is obvious, as a matter of fact I am asking the opposite question: has it done anything more than just applying Lorentz transformation. Nothing, it appears. Now, before examining the logical implications of SR, I would like to respond to MME[xperiment].
    Harold, you are an expert and concrete physicist, I am not, solve this simple problem:

    Imagin a platform A and a train T speeding N[orth] at 50 m/s. On both they are playng bowls, a man pushes [N] a ball bA, bT [mass= x Kg] with equal effort: bA moves at 51 m/s, bT at 1m/s N, is this correct, right?
    bA has an increase of KE [2550 times] greater than bT ?
    Last edited by logic; October 6th, 2011 at 08:15 AM.
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    Quote Originally Posted by logic View Post
    I do not think it is obvious, as a matter of fact I am asking the opposite question: has it done anything more than just applying Lorentz transformation. Nothing, it appears.
    There is something called "Lorentz Ether Theory" which is mathematically the same so maybe you have a point. Most physicist find Einstein's interpretation more elegant, though.
    Lorentz ether theory - Wikipedia, the free encyclopedia
    The only difference was the metaphysical[C 7] postulate of a unique absolute rest frame, which was empirically undetectable and played no role in the physical predictions of the theory. As a result, the term "Lorentz ether theory" is sometimes used today to refer to a neo-Lorentzian interpretation of special relativity.
    Now, before examining the logical implications of SR, I would like to respond to MME[xperiment].

    Harold, you are an expert and concrete physicist, I am not, solve this simple problem:

    Imagin a platform A and a train T speeding N[orth] at 50 m/s. On both they are playng bowls,
    a man pushes [N] a ball bA, bT [mass= x Kg] with equal effort: bA moves at 51 m/s, bT at 1m/s N, is this correct, right?
    bA has an increase of KE [2550 times ]greater than bT ?
    Yes, that is correct. But the kinetic energy is relative to the frame of reference. In the train's frame of reference the change in KE is the same as that of the bowling ball thrown 1 meter per second on the platform, relative to the platform's frame.
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    Quote Originally Posted by Harold14370 View Post
    Yes, that is correct. But the kinetic energy is *relative to the frame of reference. In the train's frame of reference the change in KE is the same as that of the bowling ball thrown 1 meter per second on the platform, relative to the platform's frame.
    -----------------------
    ( Harold, allow me to disagree: 'Frames of reference' are not real (like Greenwich meridian), they cannot produce KE!. KE is an absolute value, it is not even dependent on time The world is one, has no frames, if it has: just one. In our bowls-problem 'frame of reference' is earth. Edit: [I discuss in another thread])
    ------------------------
    But, anyway that is not my issue, I would like to examine what happens in real world when we apply SR.

    Imagine a *ship S orbiting the earth
    below the moon in a circular orbit r = C, C = 2π C, tangential speed 0.866 C, (at rest) L = 20m, W = 10m, H= 5m
    they communicate all the time via radio with base B

    can someone put nicely γ , the full formulas (M,T,L), and make a drawing of the hyperbolic curves they produce? please tell me,
    1) are the curves of M mass increase and Ttime increase the same?what kind of hyberbolic curves are they? or
    2) is M : (co)secant and T: k = arcs x - (ct) ?, can you plot the two curves together?
    3) can you give the SR details for such orbiting ship?

    Please answer at least 3 , so we can examine the example*
    Last edited by logic; October 6th, 2011 at 08:19 AM.
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    Quote Originally Posted by logic View Post
    Quote Originally Posted by Harold14370 View Post
    .1) No motion with respect to the aether was found. Absence of any detectable motion relative to the aether is evidence for Einstein's theory.
    2)This is analogous to a projectile's motion from a moving vehicle which goes faster if thrown forward,....
    Thanks Harold, as usual you go to the core of the problem

    1) that is the key issue. The concept of aether was unnecessary, because space is the medium, and that is exactly what Einstein did: he called "the aether" space, not explicitly, of course, but he shifted the necessary properties of aether (homogeneity, istropy...) to space, didn't he?
    No, he did not. What he did was show that the Aether, or any other "medium" through which light could be said to propagate with respect to was superfluous. He did not replace the aether with "space".

    2) isn't that what you just disproved: a bullet on a train has KE that it sums to the explosion energy, the photon, even if we consider it a particle, has only some properties of a particle, but no KE to be summed.
    Yes it does. The difference is that while the bullet's increase in energy is tied to an increase in its velocity, a photon does not change its velocity but instead changes its frequency. Higher frequency photon are more energetic.

    so isn't "invariance of C" an obvious postulate? why did we need SR?can you be more specific?
    Maybe we should discuss what "invariance of c" means first. I'll use an example.
    You are running past me with a relative speed of 0.5c We both have flashlights which we turn on the instant that you pass me.

    According to you, the light from both flashlights travel neck and neck away from you at c. After 1 sec, the front of the beams will be ~300,000 km from you. At that same time I will be ~150,000 km behind you making the distance from the front of the the beams and me ~450,000 km.

    According to me, the light from both flashlights travel neck and neck away from me at c. After 1 sec, the front of the breams will be ~300,000 km from me. At the same time, you will be ~150,000 km in front of me and ~150,000 km from the leading edge of the beams.

    This is not obvious.

    Before Relativity, there would have been only two possible outcomes that would have been considered for this scenario.

    1. The light would be effected by the velocity of the source. In this outcome I would see my light traveling away from me at c and your traveling away from you at c, the two beams would not travel neck. You would agree to the same thing. IOW, at any given moment, we would agree as to our respective distances from the leading edge of either light beam. There is no absolute frame of rest in this outcome.

    2. The light would not effected by the velocity of the source but would travel at a fixed speed relative to some medium or some frame of absolute rest. In this outcome, We would both see the beams running neck and neck, but I would see them as traveling at c away from me and you would see them moving at 0.5c away from you. Again, at any given moment we would agree at to our respective distances from the leading edge of the beams.

    The Maxwell equations eliminated the first outcome, because they showed that velocity of light was independent of the velocity of the source. This left the second outcome. However, this flew in the face of the principle of relativity, which held that there was no preferred frame of absolute rest by which motion could be measured. The principle of relativity had been a part of physics for a long, long time.

    What Einstein's invariance of c postulate did was preserve the principle of relativity while at the same time preserving the independence of lights velocity from the velocity of the source. In the process, it forced us to reconsider the nature of time and space itself. It represented a major paradigm shift in the way we looked at the universe.


    3) I read in a thread that E=m*C2 is relativity, isn't it an independent issue ascertained before SR by Planck, Wien et al., didn't SR only formalize it?
    4) the same applies to mass-increase, that is related to 3, isn't it foreign to relativity?

    While bits and pieces of what would become SR were hinted at before Einstein, they were never part of any over-arcing theory that tied them all together in one package. This is part of the beauty of Relativity, they were all shown to be the consequence of just a couple of postulates.
    "Men are apt to mistake the strength of their feelings for the strength of their argument.
    The heated mind resents the chill touch & relentless scrutiny of logic"-W.E. Gladstone


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    Quote Originally Posted by logic View Post
    Quote Originally Posted by SpeedFreek View Post
    GPS satellites had to have their internal clocks adjusted for the amount of time-dilation predicted by relativity
    Time is relative.
    Hi, speedFreek, could you give some details on that adjustment, its value and why we need it, because of the speed of satellite?
    what is time?
    I'll give it to you...from here: GPS and Relativity

    "To achieve this level of precision, the clock ticks from the GPS satellites must be known to an accuracy of 20-30 nanoseconds. However, because the satellites are constantly moving relative to observers on the Earth, effects predicted by the Special and General theories of Relativity must be taken into account to achieve the desired 20-30 nanosecond accuracy.

    Because an observer on the ground sees the satellites in motion relative to them, Special Relativity predicts that we should see their clocks ticking more slowly (see the Special Relativity lecture). Special Relativity predicts that the on-board atomic clocks on the satellites should fall behind clocks on the ground by about 7 microseconds per day because of the slower ticking rate due to the time dilation effect of their relative motion.

    Further, the satellites are in orbits high above the Earth, where the curvature of spacetime due to the Earth's mass is less than it is at the Earth's surface. A prediction of General Relativity is that clocks closer to a massive object will seem to tick more slowly than those located further away (see the Black Holes lecture). As such, when viewed from the surface of the Earth, the clocks on the satellites appear to be ticking faster than identical clocks on the ground. A calculation using General Relativity predicts that the clocks in each GPS satellite should get ahead of ground-based clocks by 45 microseconds per day.

    The combination of these two relativitic effects means that the clocks on-board each satellite should tick faster than identical clocks on the ground by about 38 microseconds per day (45-7=38)! This sounds small, but the high-precision required of the GPS system requires nanosecond accuracy, and 38 microseconds is 38,000 nanoseconds. If these effects were not properly taken into account, a navigational fix based on the GPS constellation would be false after only 2 minutes, and errors in global positions would continue to accumulate at a rate of about 10 kilometers each day! The whole system would be utterly worthless for navigation in a very short time. This kind of accumulated error is akin to measuring my location while standing on my front porch in Columbus, Ohio one day, and then making the same measurement a week later and having my GPS receiver tell me that my porch and I are currently about 5000 meters in the air somewhere over Detroit.

    The engineers who designed the GPS system included these relativistic effects when they designed and deployed the system. For example, to counteract the General Relativistic effect once on orbit, they slowed down the ticking frequency of the atomic clocks before they were launched so that once they were in their proper orbit stations their clocks would appear to tick at the correct rate as compared to the reference atomic clocks at the GPS ground stations. Further, each GPS receiver has built into it a microcomputer that (among other things) performs the necessary relativistic calculations when determining the user's location.

    Relativity is not just some abstract mathematical theory: understanding it is absolutely essential for our global navigation system to work properly!"
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    Quote Originally Posted by logic View Post
    Imagine a *ship S orbiting the earth ...3) can you give the SR details for such orbiting ship?
    Thank you everybody for your response, could we examine now a concrete example?
    can anyone make drawings or animations, that would be great!
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    Quote Originally Posted by Janus View Post
    While bits and pieces of what would become SR were hinted at before Einstein, they were never part of any over-arcing theory that tied them all together in one package. This is part of the beauty of Relativity, they were all shown to be the consequence of just a couple of postulates.
    could you tell me what postulate has the implication that E = mC, and m = γmo ? Thanks
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    Quote Originally Posted by logic View Post
    Quote Originally Posted by Janus View Post
    While bits and pieces of what would become SR were hinted at before Einstein, they were never part of any over-arcing theory that tied them all together in one package. This is part of the beauty of Relativity, they were all shown to be the consequence of just a couple of postulates.
    could you tell me what postulate has the implication that E = mC, and m = γmo ? Thanks
    1. The laws of physics are the same for any inertial frame of reference.
    2. The speed of light in invariant for any inertial frame of reference.

    Every conclusion of SR stems from those two postulates.
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    The heated mind resents the chill touch & relentless scrutiny of logic"-W.E. Gladstone


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    Quote Originally Posted by Janus View Post
    Quote Originally Posted by logic View Post
    could you tell me what postulate has the implication that E = mC, and m = γmo ? Thanks
    1. The laws of physics are the same for any inertial frame of reference.
    2. The speed of light in invariant for any inertial frame of reference.

    Every conclusion of SR stems from those two postulates.
    sorry, but my question was :"how these postulates imply E=mC and the formula for mass-increase", you do not show any implication, any math or logical demonstration

    can you tell what happens to our ship orbiting at o.866 C?
    could you make an animation?
    thanks
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    Quote Originally Posted by logic View Post
    Quote Originally Posted by Janus View Post
    Quote Originally Posted by logic View Post
    could you tell me what postulate has the implication that E = mC, and m = γmo ? Thanks
    1. The laws of physics are the same for any inertial frame of reference.
    2. The speed of light in invariant for any inertial frame of reference.

    Every conclusion of SR stems from those two postulates.
    sorry, but my question was :"how these postulates imply E=mC and the formula for mass-increase", you do not show any implication, any math or logical demonstration

    can you tell what happens to our ship orbiting at o.866 C?
    could you make an animation?
    thanks
    Actually your question was "could you tell me what postulate has the implication that E = mC, and m = γmo ?"

    To which Janus answered correctly, that everything in SR comes from the two postulates he quoted. You didn't ask how.

    A spaceship moving at 0.866c relative to you will be shortened to half its original length, in its direction of travel, and time on board that ship will pass at half the rate it passes for you as you observe that spaceship.
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    Quote Originally Posted by logic View Post
    what postulate has the implication that E = mC, and m = γmo ? Thanks
    implication implies how
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    Not one of them implies that (and not both together either).

    These so called "postulates" are inclusive to the theory (so Logic correctly noticed a misplaced use of the word implication or implying would mean including) because Einstein worked from them but didn,t proof them.
    You can,t ask that work then (or Einstein through studying his work) to proof these theorems. It only proofs then that the postulates are inclusive to the theory.

    But also, the postulates themselve don,t include that C is the same for all directions for the theory. C for a specific direction can be the same for all inertial frames of reference but different then C in other directions. That,s just not consistent with the idea of a spherical propagation.
    That would mean the laws of fysics are different then but that,s not the same as "the laws of fysics are the same for any inertial frame of reference".
    Last edited by Ghrasp; October 5th, 2011 at 10:19 AM.
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    thanks, so, back to square one. SR is just an "elegant" formulation of Loretz transformation.

    now, our ship is orbiting and has become a square, 1 second on ship is 2 seconds on earth, what happens to radio waves, when they enter the ship, and what happens to gravity? is it half its normal value?
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    Quote Originally Posted by logic View Post
    Quote Originally Posted by logic View Post
    what postulate has the implication that E = mC, and m = γmo ? Thanks
    implication implies how
    Yes, but you didn't ask about the implication itself. You asked which postulate had the implication. You got the correct answer. Semantics.

    Contrary to what Ghrasp says, Einstein's 1905 paper on mass/energy equivalence was based upon the work of Maxwell and Hertz, with the addition of the axioms of special relativity, and led to
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    Quote Originally Posted by SpeedFreek View Post
    Quote Originally Posted by logic View Post
    Quote Originally Posted by logic View Post
    what postulate has the implication that E = mC, and m = γmo ?
    implication implies how
    Yes, but you didn't ask about the implication itself. You asked which postulate had the implication. You got the correct answer. Semantics.
    1) Einstein's 1905 paper on mass/energy equivalence led to
    [Janus] added
    Quote Originally Posted by Logic View Post
    sorry,...[Janus]...you do not show any implications...
    I hope you are joking, quibbling
    it is advisable you check the words you are using, before you continue a discussion, please wiki: semantics, logical implication, also these articles can help: theorem, mathematical proof, logic, proposition etc.
    a correct answer must start from one[or more] postulate/premise and show how, from it, you arrive at the conclusion that E=mC, or whatever you want to prove.

    your proposition 1) implies you know the answer, how it led to that conclusion, unless you are joking. Now, I ask you explicitly [without understood implication for a scientist]
    please, show me how the paper on mass/equivalence led to that conclusion and not to E=mC/2
    Last edited by logic; October 6th, 2011 at 08:37 AM.
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    Quote Originally Posted by logic View Post
    please, show me how the paper on mass/equivalence led to that conclusion and not to E=mC/2
    Einstein’s derivation of E=mc^2 What’s new
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    the weak link in that link is point 5. the answer to that is in my thread about the absolute value of energy in one electron. Thread was not answered.
    Quote Originally Posted by logic View Post
    now, our ship is orbiting and has become a square, 1 second on ship is 2 seconds on earth, what happens to radio waves, when they enter the ship, and what happens to gravity? is it half its normal value?
    can anyone continue discussion?
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    Quote Originally Posted by SpeedFreek View Post

    Contrary to what Ghrasp says, Einstein's 1905 paper on mass/energy equivalence was based upon the work of Maxwell and Hertz, with the addition of the axioms of special relativity, and led to
    And so they where inclusive to Einsteins work as premisse then because he worked further from what where implications from their work.

    But maxwells work didn,t lead to a spherical propagation and postulate 2 is not saying that either.

    As for frequency ; what is the frequency of a gps clock if it,s set off from the fysics definition of a second ? One thing for sure.... it,s not 1/1=1/second.
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