Relativistic Mass ?

Discussion in 'Pseudoscience Archive' started by Lakon, Jan 6, 2013.

  1. quantum_wave Contemplating the "as yet" unknown Valued Senior Member

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    But before I changed velocity I had no sense of motion and I saw and then sat in the car that I observed to be standing still relative to the road, so I'm not blind to the road. I observed my motion relative to the road as I accelerated and could see the road go by under me from front to back. All very up and up, I was pushed back by the acceleration.
     
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  3. Prof.Layman totally internally reflected Registered Senior Member

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    The accepted veiw in science is that the acceleration of an object that is close to the speed of light would not be Galilean Invariant. It would be harder for an object observed traveling at a relative speed close to the speed of light than it would for the same acceleration that is not close to the speed of light. But, in Galilean Relativity there would be no way to know which one is actually traveling close to the speed of light. So then there would be no way to determine which one had a harder time accelerating.

    It is just the wrong common sense approuch that has found its way into science, there is no theory that actually proves that it would be harder for one object to accelerate because of its relative motion. It is just, "yes sir physics", that says an object cannot travel the speed of light. It gets the correct answer but in the wrong way.
     
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  5. Prof.Layman totally internally reflected Registered Senior Member

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    The is no difference between acceleration and deceleration other than the direction of your increase or decrease of velocity. A change in velocity can be an increase or decrease depending on the frame of refrence that you are in.
     
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  7. quantum_wave Contemplating the "as yet" unknown Valued Senior Member

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    Were you addressing my post because I'm not sure I see how. Did your response address my question or was it aimed at the thread in general? If to me, can you relate it to my post more specifically?
     
  8. Prof.Layman totally internally reflected Registered Senior Member

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    I was addressing the comments to you because I have seen you post that you think that the increase in mass is only relative to the outside observer and not the observer that is traveling along with that frame. I think that is how it should be, and you probably will not get much of an argument out of people because of this. I just think you should be aware of the fact that it is taught as science that they would detect the same mass increase as an outside observer and this keeps them from traveling faster than the speed of light relative to them. So you could run into someone that doesn't agree with it but swears up and down that is how it is taught as real science, because in some places it actually is. It hasn't really seen much popularity on the internet. And a lot of people on the internet would agree with me.
     
  9. quantum_wave Contemplating the "as yet" unknown Valued Senior Member

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    Thank you for the clarification. I have derived much of my understanding, right or wrong, from a variety of sources and views and have not taken anything that I have been taught as gospel unless I thought if fit with my unindoctrinated perspective, lol.
     
    Last edited: Jan 10, 2013
  10. billvon Valued Senior Member

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    Correct. However, that is only true to an outside observer. To an observer on the object, acceleration works like it always does.

    That information is not needed since an observer on the object sees no change in his ability to accelerate; hence no need to know which direction he is going in.

    Agreed; indeed there is no theory that even claims this is the case (for an observer on the object, that is.)

    (I also agree that many people do not make that distinction.)
     
  11. Prof.Layman totally internally reflected Registered Senior Member

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    Then this would create some type of twin paradox. The oustside observer would have to measure the same velocity relative to the ship as the ship measures to the outside observer. You couldn't end up with either of them measuring a different velocity between each other. There would be a "velocity paradox", the relative velocity they measure between themselves should always be the same.
     
  12. billvon Valued Senior Member

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    That assumes that their time bases are the same - which they are not. Velocity is distance over time, and as the time metric changes, so do velocity measurements. Thus a ship that is accelerating will see a different velocity in objects around their ship than it would ift hadn't changed its speed.

    However, in the long term you still have the twin paradoxes caused by this changing time metric on both ships.
     
  13. brucep Valued Senior Member

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    There is no increase in mass because mass is an invariant. The increase associated with the acceleration and instantaneous velocity is momentum and energy. Mass is an invariant and NOT frame dependent. That's the real science regardless what you think. Anybody on the internet or off the internet that agrees with the nonsense your spewing is as clueless as you are.
     
  14. Prof.Layman totally internally reflected Registered Senior Member

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    No, I just assume that v' = d' / t' and v' = v so then v' = d / t. The only changes a ship would see in the velocity of other objects is due to the change in the relative velocity of those objects. I see no reason why relativity would say something different about the speed of other objects other than what Newton would say about it because of the same changes in speed. There is no theory of relativistic velocity. There is addition of velocity but I think that is for another discussion.
     
  15. Prof.Layman totally internally reflected Registered Senior Member

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    Do you not know what invariant even means? Or have you not even learned about relativistic mass increase? It is textbook...
    I know it isn't covered in that book you have been reading.
     
  16. OnlyMe Valued Senior Member

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    Well.., acceleration is nothing more than a change in velocity (over time), so in that sense acceleration and deceleration are the same thing.

    When we distinguish between the two, we are making a judgement that the acceleration is relative to some other (usually fixed) frame of reference. When we drive a car we accelerate and decelerate relative to the road we ride on, but from the frame of the car the two are both accelerations. In both cases the car experiences a change in velocity (over time).
     
  17. OnlyMe Valued Senior Member

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    "Relativistic mass" is pretty much an archaic concept, which does more to add confusion to lay oriented discussions than any enlightenment.

    Mass is invariant as you have been told, several times now. What was once described as relativistic mass, is an object's frame dependent momentum.

    Try working your way through, The Concept of Mass..., by Lev Okun

    Note, the above link is to a newer publication of the paper than I have and I have not read through it to note any changes, additions or deletions. The original paper did a pretty good job of describing the issue...
     
  18. Prof.Layman totally internally reflected Registered Senior Member

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    http://en.wikipedia.org/wiki/Invariant_(mathematics)

    "In mathematics, an invariant is a property of a class of mathematical objects that remains unchanged when transformations of a certain type are applied to the objects."

    The mass is observed to be different with different velocity, so then the relativistic mass would not be invariant to velocity.
     
  19. OnlyMe Valued Senior Member

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    Like I said try reading through the paper in the link I gave in the last post. Mass does not vary with velocity. An object's kinetic energy does, which means its momentum does, but then both of those are frame dependent. The mass is not. It is invariant.

    Just do a little reading... There is some math but not too much I think.

    I will add that in discussions between physicists, use of "relativistic mass" does not generally cause problems. Mostly because everyone pretty much understands what they are talking about... And because of that, you will often find the phrase even in discussions, by physicists, intended for a lay audience, which very often does lead to misunderstanding... As has been here demonstrated!
     
  20. Aqueous Id flat Earth skeptic Valued Senior Member

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    The seat transmits the force developed by the traction of the wheels onto your body. This is easily resolved by choosing the inertial reference frame at the initial conditions before the car was started.
     
  21. Prof.Layman totally internally reflected Registered Senior Member

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    That paper is bull, it doesn't even have the equation for relativistic mass in it, and right now I don't see a link that has the equation that I was talking about. I have seen it in first year physics text. Mass is said to be directly associated with velocity.
     
  22. Motor Daddy Valued Senior Member

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    You seem a little confused. To be more precise than your word salad, acceleration is the rate of change of velocity. If the initial velocity is 100 m/s and one second later the final velocity is 125 m/s then the rate of change of velocity (acceleration) for that 1 second was 25 m/s^2. But in reality, since you don't know your absolute velocity then you have no way of knowing the initial or final velocity. You also don't know which direction of travel you are traveling, so you have no way of knowing if your velocity is increasing or decreasing when you accelerate.
     
  23. Motor Daddy Valued Senior Member

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    Maybe you can clear up my confusion. You are traveling down a road in a car at a constant speed. You step on the brake pedal. Did you increase velocity or decrease velocity?
     

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