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Thermodynamics Destroys SR (end of whole story)

  1. Mar 24, 2004 #1
    1. Suppoes clock A and clock B are of identical construction, both in inertial reference frames, and let the relative speed be zero.

    Therefore, they tick at the same rate.

    2. Let clock B be located inside a ship.

    As long as the ship doesn't turn on its engines clock B will remain at rest with respect to clock A, but if the ship turns on its engines then clock B is being accelerated by an outside force, and is no longer in an inertial reference frame.

    Let us now suppose that the ship is uniformly accelerating, thus the speed of clock B relative to clock A is getting faster and faster.

    Clock A is in an inertial reference frame, and can use the time dilation formula to conclude that clock B ticks slower and slower, and if the relative speed reaches c then clock B stops ticking (else the time dilation formula leads to division by zero error).

    However, if time inside the ship stopped passing, then there would be no motion inside the ship, which would mean that the ship's temperature reached absolute zero degrees kelvin, which is thermodynamically impossible. Thus, clock B cannot be accelerated from rest to the speed of light (by thermodynamics).

    In conlusion, as clock B moves faster and faster, its temperature gets closer and closer to absolute zero, and can be made arbitrarily close to zero, as the relative speed v gets arbitrarily close to c, but never reach absolute zero (and never reach speed c).

    Therefore, SR is overthrown.


    Well, let us suppose that after some amount of time, the ship stops uniformly accelerating, and coasts along at some constant final speed V which is necessarily less than c. (V is the final relative speed of the clocks to one another)

    After the ship stops accelerating, clock B is again in an inertial reference frame. Hence, the time dilation formula can be used in clock B's frame, and the conclusion is that clock A is now ticking slower than clock B.

    Likewise, by the same formula, clock A concludes that clock B is ticking slower than clock A.

    Thus, one theory leads to two conclusions:

    After the ship stops accelerating:
    1. Clock A is ticking slower than clock B
    2. Clock B is ticking slower than clock A

    From which we can extrapolate the explicit contradiction that:

    Clock B is and isn't ticking slower than clock A.

    Thus, thermodynamics overthrows SR.

    Yet, the rate of clock B slowed during its acceleration, and went back to its normal rest rate as soon as the uniform acceleration was over.

    At that point, clock B now ticks at its rest rate, which is the same as the rest rate of clock A. And clock A's rate never changed. Hence, at the end of the event, clock B does and doesn't tick at the same rate as clock A, which is impossible.

    Therefore, the time dilation effect isn't relative.
  2. jcsd
  3. Mar 24, 2004 #2

    SR doesn't say that passengers on the space ship will see clock B ticking slower when the space ship is moving. In fact, SR says just the opposite: passengers on the space ship will see clock B ticking at exactly the same rate, no matter how fast the ship is moving.
  4. Mar 24, 2004 #3
    You do not need thermodynamics to reach this conclusion. Einstein in his work demonstrated that nothing can make the leap from sub-light speeds to over-light speeds. Anything, such as your clock, that is traveling below the speed of light will always do, and you cannot accelerate it beyond the speed of light.

    As for your claim that relativity is debunked by thermodynamics, it results from your misunderstanding of it.
  5. Mar 25, 2004 #4
    I didn't say passengers on the ship will see their clock slowing, the logic of the argument is saying this:

    If you are in the accelerating ship, then you are getting colder and colder, as the speed of the ship approaches the speed of light.


    As the ship accelerates, it ticks slower and slower, relative to clock A.

    In other words, even if you don't sense time slowing down while on the ship, still there is a mathematical relation to your clock reading, and a reading on a clock outside your ship, and then just follow the mathematical logic.

    There is really nothing to it.


    Best Regards,

    The Star
    Last edited: Mar 25, 2004
  6. Mar 25, 2004 #5
    Re: Re: Thermodynamics Destroys SR (end of whole story)

    No no no chen, it is you who are misunderstanding it.

    First off, I didn't claim that thermodynamics is the only way to reach the conclusion that no object can be accelerated from rest to the speed of light. In fact, that conclusion can be reached using thermodynamics, special relativity, OR even Quantum Mechanics.

    Lastly, relativity can be debunked by thermodynamics. The conclusion you are trying to reach is this:

    The temperature of clock A is greater than the temperature of clock B, and the temperature of clock A isn't greater than the temperature of clock B.

    And you are trying to reach the previous conclusion using only one assumption, namely that the time dilation formula is true.

    There is really nothing to either the thermodynamic argument, or the accelerating reference frame argument. Please keep in mind, that they are different arguments with the same conclusion.

    Best Regards,

    The Star
  7. Mar 25, 2004 #6


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    Staff: Mentor

    If your clock ticks at the same rate (according to you, standing there next to the clock) and the speed of molecular motion hasn't changed (according to you, standing there next to the clock), so how can you be getting colder?

    That's the funamental postulate of relativiy (not just Einstein's version): for you standing there next to your clock, nothing changes in your local frame of reference.

    Also, you mention there is logic to you argument: that statement which apparently contains the logic (it has an "if" and a "then") does not follow logically as you haven't shown why the "if" and the "then" should be connected.
    Last edited: Mar 25, 2004
  8. Mar 25, 2004 #7


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    Science Advisor

    "...from B's frame of reference..."

    "...from A's frame of reference."

    This makes both of these statements true to experimental observation.
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