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Moving faster than light cannot stop biological aging! Or can?

  1. Nov 1, 2013 #1
    Hi everyone, before I post I apologize for my bad English!
    I am not a physicist but I am interested in this stuff (I've read relativity theory and...)
    But I have a question regarding time traveling
    Imagine that it is true that we can travel at speed of light...So here is the famous example of identical twins:
    one of whom makes a journey into space in a high-speed rocket and returns home to find that the twin who remained on Earth has aged more.
    it could be that, aboard the space-ship, two years of flight-time have passed - on-board clocks and calendars show that two years have elapsed, and both spaceship and travelling twin have aged by exactly that amoung of time. On Earth, however, a whopping 30 years have passed between the spaceship's departure and its return. Just like all other humans on the planet, the twin on Earth has aged by 30 years during that time.

    So here is my question:
    Does the brother who was on the space looks younger? I mean his face? is it true that one of them looks like a child while the other one looks like an adult? Does biological ageing like growing cells and chemical reactions in our body go slower like time?
    Or it is just a matter of relativity meaning that they just had different experience of time and both of them are look the same regarding their face and body?
     
  2. jcsd
  3. Nov 1, 2013 #2

    Doc Al

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    Yes! The traveling brother really is younger.
     
  4. Nov 1, 2013 #3
    Do you know why? why do you say that? any proof or logical explanation?
     
  5. Nov 1, 2013 #4

    Nugatory

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  6. Nov 1, 2013 #5

    Doc Al

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    You seem to accept that ordinary clocks carried by the traveling brother would show less time. Why do you think that biological "clocks" would work differently? (All temporal processes show the same effects.)
     
  7. Nov 1, 2013 #6

    Dale

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    If clocks slow down then so must biological aging, according to the first postulate of relativity.

     
  8. Nov 1, 2013 #7
    So you think our body clock (our heartbeat or biological clock) works as a CLOCK? you consider it as a kind of TIME? what if our body is different with what we think? I mean what if aging process does not follow physics principle?
    I think the consent of time that we have about ourself is something like interior feeling of changes of our organs and changes happening around us... So the traveling brother ageing would not affected by his speed, he would just experience changing events in different scale

    Imagine two person are given 100 years of living in our planet. Mr.A start traveling at speed of light. Mr.B start a normal life.
    I think Mr.A would die just in one week which is equal to 100 years on living of Mr.B.....They would die together !!
     
  9. Nov 1, 2013 #8

    Nugatory

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    we've tried this experiment - not with people, but with various subatomic particles of known lifetime. It doesn't work the way you're expecting - the moving particles die after the stationary ones, in exactly the way that relativity predicts.
     
  10. Nov 1, 2013 #9

    Dale

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    Yes. Definitely.

    That simply is not the case. The human body obeys the laws of physics. If you step off a building the human body is subject to gravity and will fall. If you grab an electrical wire the human body is subject to electromagnetism and will conduct current. If you swallow a radioactive substance the human body is subject to the strong and weak nuclear forces and will radiate. The body is subject to all of the laws of physics and all of the laws of physics demonstrate time dilation.

    As Nugatory mentioned this experiment has been done with particles and your thought is contrary to the actual measured behavior of the universe.
     
  11. Nov 1, 2013 #10

    A.T.

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    If a light-clock slows down then aging must too. Otherwise you get different outcomes, for different observes.

    Imagine you are locked in a cage. The lock is controlled by a light clock, that opens after 1 day in your frame so you walk out. An observer who moves fast relative to the cage will observe the light clock slown down and open after 1000 years. If he wouldn't observe your aging slown down, he would see you die in the cage. But that contradicts the fact that you walked out of the cage.
     
  12. Nov 1, 2013 #11
    Interesting.
    I wish I were Physicist
    So just to know more, would the effects of traveling at speed of light on ageing and time, happen in slower speed?
    For example if you travel with a car at high speed you are getting older slower than a person who walks?? or no you should be out of planet earth to see this happening?
     
  13. Nov 1, 2013 #12

    Nugatory

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    Yes, although the effect is too small to notice at those speeds. Time dilation is just barely detectable with the most sensitive equipment (yes, this experiment has been done too) with clocks carried in jet aircraft.
     
  14. Nov 1, 2013 #13

    phinds

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    I find it a bit odd that no one has commented on the subject line of your post. It is impossible for anything with mass to travel AT the speed of light, much less faster than light. All of the discussion above is about situations traveling SLOWER than light.
     
  15. Nov 1, 2013 #14
    Yes you are right, I wanted to change the topic but I couldn't. Sorry about that but all the discussions are what I was searching for
     
  16. Nov 1, 2013 #15
    Talking about most sensitive equipment, like atomic clock, I was wondering how this clock works?
    I know it uses the resonance frequencies of atoms and the resonator is regulated by the frequency of the microwave electromagnetic radiation emitted or absorbed by the quantum transition of an atom...but how they measure this frequency? I mean how they change it into time scale? like seconds!?
     
  17. Nov 1, 2013 #16

    pervect

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    That part is simple. The period of the radiation is 1/frequency, and the period of the radiation has units of seconds.

    So you can either measure the frequency and convert it to a period, or measure the period, and you get units of seconds.
     
  18. Nov 1, 2013 #17
    I guess I have to understand the nature of time! I think it is the changing states of matter and energy. and it is nonsense without moving, something like space-time, but does it really true? is this the true concept of time? or is there any scientific definition of time and its nature and concept?
     
    Last edited: Nov 1, 2013
  19. Nov 1, 2013 #18

    Ibix

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    According to Einstein, time is what clocks measure. Distance is what rulers measure. Slightly suprisingly, the two concepts aren't completely separate.

    That's about all there is to know about the nature of time.
     
  20. Nov 2, 2013 #19
    yes time is what clocks measure but it is not its nature, it is just device for human to make it understandable, kind of agreement. I'm looking for its nature, from where it is stemming?
     
  21. Nov 2, 2013 #20

    Vanadium 50

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    That's not a question physics can answer.
     
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