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Paticle accelerator in space ship help pls

  1. Apr 18, 2008 #1
    Referring to fig 1


    I have a particle accelerator in a space ship. The accelerator part is a point A and the particles are accelerated to point B. The velocity of the particles is measured by the observer at D and the energy input is measured by a meter at E.

    All of the points and the observer are at rest wrt the space ship

    V is the velocity of the space ship which of course will be unknown to the observer.

    I want to try an experiment to see if the observer can tell if he is moving.

    While the space ship is stationary on the launch pad the observer accelerates a particle up 0.99c as measured by the observer and measures the energy required. Lets say the energy to do this is X

    While the space ship is still stationary on the launch pad the observer turns the accelerator through 180 degrees so point B is now where point A used to be and point A is where point B used to be. The observer again accelerates a particle up 0.99c as measured by the observer and measures the energy required. Lets say the energy to do this is Y

    Will Y be equal to X I think it would be does anyone disagree?

    Finally the rocket takes off and accelerate until it reaches it terminal velocity at which time it will achieve a constant velocity.

    The observer now accelerates a particle up 0.99c as measured by the observer and measures the energy to required. Lets say the energy to do this is W.

    The observer again turns the accelerator through 180 degrees so point B is now where point A used to be and point A is where point B used to be. The observer again accelerates a particle up 0.99c as measured by the observer and measures the energy required. Lets say the energy to do this is Z.

    Assume the space ship is traveling at a velocity of 0.5c

    Is
    X = Y
    Z = X
    W = X

    will all the energy measurements be the same. If they are not then the observer will think two things
    1 something is broken
    2 I must be moving and the velocity on me moving is adding or subtracting from the velocity of the particle thus requiring less or more energy to accelerate it.
     

    Attached Files:

  2. jcsd
  3. Apr 18, 2008 #2

    paw

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    Because your observer and apparatus are all in the same inertial reference frame both before launch and after acceleration to 0.5c the results of the experiment will be the same in both cases. Thus you will be unable to determine from this exercise that you are in motion without reference to an outside frame.

    Having read some of your other posts I have to say you are persistant. This is a good thing in many ways. But believe me, many, many people have tried to think of ways to prove some form of absolute motion without success. Unless you stumble on some new physics you are doomed to failure.
     
  4. Apr 18, 2008 #3

    D H

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    It appears you are assuming there is some absolute reference frame in which one can say the velocity of the space ship is V. No such absolute reference frame exists.

    Ignoring gravity, X=Y=W=Z. (Since the vehicle is initially sitting on a launch pad, X will differ from Y by some amount, most likely an immeasurably small amount.)
     
  5. Apr 18, 2008 #4
    Im persistant because I know at the core of my being the science is wrong

    In a particle accelerator energy input is directly proportional to the absolute velocity of the particle not its relative velocity. Keep in mind that particles are ballistic the velocity of the frame adds to the velocity of the particle at rest within that frame. It is irrelevenat if an observer within that frame doesnt know they are moving are know the velocity of the frame. The velocity still adds, just cos it is unknown is irrelevant.

    You are in a moving car and you throw a ball you see the ball moving at the speed of your throw. An observer standing on the side of the road see the ball moving much faster as the speed of the moving car adds to the speed of the ball. The true energy that the ball contains is energy from the car and energy from the throw. If the ball hit a pasenger in the car it wouldnt hurt much as the passenger is moving away from the ball at the same velocity as the car. If the ball flew through the window of the car and hit the dude on the road it would knock him over. What is the true energy of the ball . Did the energy of the ball miraculaously increase as it flew from inside the car (one frame of reference) to oustside the car (a different frame of reference) ?

    If energy was proportional to reltive velocity it would be possible to accelerate a particle faster than c. ie get in a space ship travel east at 0.5 c and accelerate the particle easterly at 0.7c the particle is now travelling faster than c which would require infinite energy!

    Ignoring gravity demostrate to me why I should accept your answer ?

    I think you should be a little more accurate an absolute frame of refernce doesnt exist YET. I love absolute statements in sceince they make me laugh
     
  6. Apr 18, 2008 #5

    D H

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    Both of these statements are incorrect. There is no such thing as absolute velocity, and at relativistic speeds velocities are not additive. You can do as many erroneous thought experiments as you want. Physicists have done real experiments that prove that velocities do not add at relativistic speeds.
     
  7. Apr 18, 2008 #6

    Hootenanny

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    Your understanding of relativity is fatally flawed. Both observers (inside & outside the car) are correct, this is the essence of special relativity. Even though the calculated energy of the ball differs between difference reference frames all the energy values are correct in that reference frame. The only calculation that will not differ between the different reference frame travelling at different velocities is the invariant mass i.e. calculated in the ball's rest frame.
    No, the energy didn't 'miraculously' increase in energy. The measured energy of the ball depends on the relative motion of the reference frames
    Okay, in future we shall make predictions based on an as yet unknown theory :yuck:. Tell me, how shall we analyse phenomina if not using current theory?

    I'm not going to bother replying to the rest of your post. I suggest you start by learning some physics. Once you understand current theory, then you may 'challenge' it, but right now you don't understand the theory you are trying to disprove. Perhaps if you understood it you might accept it.
     
  8. Apr 18, 2008 #7
    The first thing you have to accept is that there is no such thing as absolute motion.
     
  9. Apr 18, 2008 #8

    russ_watters

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    And I love irony. Nevertheless, Special Relativity has been thoroughly tested in its hundred years of existence. The flaw that you think exists would be huge(one of the two main postulates!) if, in fact, it did exist. It doesn't. You are wasting our time and yours.

    I would also like to point out to you that this forum has a rule against posting unverified personal theories. You continually violate this rule. Please stop.

    [edit] You have a lot to learn about physics:
    Before you start to tackle Einstein's Relativity, you will need to learn about how Galileo described the universe. Your understanding of that is wrong as well and Galilean relativity is an important precurser to Einsteinian.
     
    Last edited: Apr 18, 2008
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