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The reason why you can't accelerate to light speed

  1. Jun 30, 2013 #1
    I had thought about it, and came to this conclusion:

    In order to accelerate your mass faster and faster, you'll need a higher and higher amount of energy in order to move yourself; this energy (which could be considered mass?) curves space/time and causes time dilation.

    How off am I?
  2. jcsd
  3. Jun 30, 2013 #2


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    Staff: Mentor

    Not even in the right zip code :smile:
    The effects of special relativity (length contraction, time dilation, relativity of simultaneity, and the like) have nothing to do with space-time curvature.

    Space-time curvature only comes n when gravitational effects are present.
  4. Jun 30, 2013 #3
    I thought time dilation was the result of the curvature of space/time :cry:
    Is there an explanation for it?
  5. Jun 30, 2013 #4


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    Staff: Mentor

    There is an explanation, and your best bet is to start with an exposition of special relativity starting from Einstein's two postulates of special relativity. If you want to really follow in the footsteps of the master, you'll start with Einstein's 1905 paper "On the electrodynamics of moving bodies" (easy to find online); but although the math is not especially demanding, it's not exactly a gentle tutorial introduction. There a bunch of other good ones out there - I'll let some other posters weigh in with their suggestions.
  6. Jun 30, 2013 #5
    try this current discussion:


    nobody really understands why only massless particles can travel at 'c'....we have theories that describe such experimental observations, but if the observations were different we would have developed different theories to match different observations.
    Last edited: Jun 30, 2013
  7. Jun 30, 2013 #6
    'curvature' is a complicated mathematical subject. It turns out only gravity causes what scientists refer to as spacetime curvature. Time dilation and length contraction effects in special relativity [SR} do not create spacetime curvature that is attributed to gravity in general relativity [GR}. It turns out that mathematically the speed which causes time and space is morph into each other in SR, whose effect is to keep the speed of light a constant for all inertial observers, is quite different than the gravitational potential of GR which actually 'curves' spacetime. [Mathematically, vectors adequately describe time dilation and length contraction, but it takes multi dimensional vectors called tensors to describe gravity. Gravity is unique among the 'forces' of nature. ]
  8. Jun 30, 2013 #7
    I heard that Einstein came upon time dilation through the implication that c is constant for any observer. Is there a deeper "cause" to it than that (as far as general relativity says)?
  9. Jul 1, 2013 #8
    The history is here:


    As I already posted, time dilation and length contraction were utilized by Einstein in SR.

    Each was being studied icw 'aether' just when Einstein was working on SR. He utilized those concepts realizing 'c' is constant and that space and time are not...so no 'aether' is required...
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