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Constant Motion being relative leaves me with a paradox. I must me missing something,

  1. Mar 16, 2009 #1
    this is my 1st post, and its a question that i had developed, most likely out of ignorance, so plz save me from my sad paradox. lol
    Thank you, in advanced.

    I understand if i where floating in the bulk of space with no visual queues to give me aid in telling me if I were moving, i could simply say im stationary but just as easily be in constant motion.

    And if say, you are also out in space facing me and we are about to pass each other, I could say I am stationary and you are passing me, and well you have equal grounds of saying. Im passing you.

    Now say we pass at 95% the speed of light. I appear, to you, to be going 667 million miles per hour, but to me, you appear to be moving toward me at that speed.

    And here is paradox number 1, the one i understand.
    We both see each other in slow motion. All my gestures appear slower then yours, but i see all your gestures are slower then mine.
    I see your slower then me, and You see im slower then you.

    now this is my sad paradox.
    say you and your brother are physicists, and you both decide to do an experiment. You are going to get into a ship and without acceleration travel at 95% the speed of light, away from earth, and you will bring a magical telescope and as you stay at your constant speed you will observe your brother.

    Your brother with his magical Telescope will watch you, observing you.

    now, you launch instantly and can now say earth is leave you at 95% the speed of light,
    and your brother can now say u are leaving earth at 95% the speed of light.. we find are selves back at relative Constant Motion

    you travel 3 years, YOUR 3 years not your brothers. in your 3 years its been 30 for your bro.
    your brother had watched you for 30 years.
    you watch your brother for 3.

    this is the mind meld.

    how can your brother move slower then you, and still have watched longer?
    this leaves you watching your brother's slow motion 30 years, in only 3 years.
    were logically if you watched 30 years in slow motion, it will most definitely take longer then 30 year to watch it in its entirety

    the only way for you to watch 30 years within 3 years is if the 30 years where in fast motion.

    but according to constant motion(not accelerating), there is no fast motion at play.

    would u miss 27 years in your instant acceleration?
  2. jcsd
  3. Mar 16, 2009 #2


    Staff: Mentor

    Re: Constant Motion being relative leaves me with a paradox. I must me missing someth

    See the http://math.ucr.edu/home/baez/physics/Relativity/SR/TwinParadox/twin_paradox.html" [Broken] FAQ.
    Last edited by a moderator: May 4, 2017
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