Einstein got it all wrong?

Discussion in 'Physics & Math' started by scifes, Mar 26, 2011.

  1. Emil Valued Senior Member

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    2,801
    No, length contraction is happening on the earth or on the planet, it depends where you are.Lorentz transformation does not apply outside the corps, which are in relative motion one from another.
    So it does not applies to the space.

    Very important to note that Einstein did not say so, he claimed the opposite.
    ........................................................................................................ Theory of relativity,Scope
    ........................................................................................................ Special relativity
     
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  3. Janus58 Valued Senior Member

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    Wrong. Length contraction applies to measurement of length whether that measurement is of an object or the distance betwwen objects.
    Wrong again.
    Nothing in this links disputes what I've said.
     
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  5. OnlyMe Valued Senior Member

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    The Lorentz transformations define length contraction. Lorentz developed the equations before the introduction of special and general relativity, in an attempt to defend his ether model by explaining why the Michelson & Morley experiments did not detect the motion of the earth in relation to a stationary ether. Within this context the length contraction did not apply to space, only to the length of an object in motion.

    Einstein incorporated the Lorentz Transformations into the special theory of relativity. Still they applied to the object in motion not space.

    General relativity evolved as a model of gravity from an application of special relativity to the context of a 4 dimensional Minkowski space-time, in which the curvature of space is curved. The length contractions of the Lorentz transformation played a major role.

    I am not sure that strictly speaking curved space is the same as length. Since even if a light year were curved in a way that from a theoretical external perspective it appeared shorter, light would still take the same time to travel the distance. In any case it is a dramatically over simplified explanation of the involved theories and concepts.

    Some of the above represents my an attempt to explain, things not directly addressed, at least in the early presentations of the involved theories.
     
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  7. Emil Valued Senior Member

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    I only talk about special relativity and not about general relativity.

    @ scifes,
    Im sorry but it seems that Einstein was right.
    Everything I've read so far I agree with Einstein and I plead on his behalf against various interpretations and additions to special relativity.
    ...................................................................................History of special relativity
    ...................................................................................History of special relativity, Special relativity
     
  8. OnlyMe Valued Senior Member

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    Good reference. And from Wiki.

    Even though I have been reviewing much of that early work, over the past couple of years, there are a couple of historical markers in there I had not run across.


     
  9. Emil Valued Senior Member

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    2,801
    I have not found in the work of Einstein, where he asserts, can not exceed the speed of light. If anyone does, please give the link.
    Can not exceed the speed of light is an assumption that leads to the conclusion that time is not universal but is variable depending on the relative velocity of two bodies.
    For me it is more plausible assumption that time is universal, invariable and leads to the conclusion that can exceed the speed of light.

    But suppose that the first version is correct.
    This means:
    ............................................................................................Special relativity
    I define two events as follows:
    The body A moving at speed V1 when it reach the point X in space, is the event E1.
    E2 event is when the body B moving at speed V2 it reach the same point X in space.
    When both E1 and E2 events taking place simultaneously means that they collided.
    For me it is unacceptable "Two events, simultaneous for one observer, may not be simultaneous for another observer if the observers are in relative motion."

    So if a meteor is on a collision course with Earth,
    We only have to send an "observer" in space with a proper speed so that the collision do not occur.

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  10. onelight Registered Member

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    It will still occur, just the timing and relative velocities of the impact will depend on the observer. Such a shame that simple newtonian physics and math refuse to explain the matrix we are in... You should have taken the blue pill...
     
  11. Janus58 Valued Senior Member

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    If SR only applied to objects and not the distances between them, it would be internally inconsistent. A classic example would be a light clock which bounces light along a path parallel to motion as well as perpendicular to it, such as in the following animation:

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    Here we see two light clocks, one at rest relative to us and the other in motion. They both have light pulses bouncing back and forth between two sets of mirrors, one pulse going up and down and the other left and right.

    Note that the with the "Stationary" clock the pulses take an equal amount of time to make the round trip between mirrors.

    For the moving clock, for the same to happen (as it must), the distance between the left and right mirrors must be contracted as measured by us. (Remember, someone moving with the light clock will measure the distances between the Up/down mirrors as being the same as that of the Left-right mirrors for his light clock and will measure the other clock as being contracted in the left-right direction.)

    It makes no difference if our light clock is a single object with the mirrors rigidly attached to each other or if the mirrors are independent objects which just share a common frame, The distance between the mirrors must undergo length contraction as measured from a frame from which they are measured as having relative motion. Anything else would violate the two postulates of SR.

    So length contraction applies to the distance between independent objects sharing a frame just as much as it does to the objects themselves.
     
  12. Janus58 Valued Senior Member

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    The Relativity of Simultaneity applies to events that are separated by a distance that is parallel to the line of Relative motion. For example, if you have a spaceship traveling at some velocity with respect to an observer, Two events that happen simultaneously in the tail and nose of the ship according to someone in the ship, do not happen simultaneously according to our outside observer. Also, if you were in a spaceship some distance from another ship and traveling along the distance separating you. Observers in each ship would disagree as what their respective clocks read at any given instant.

    On the other hand, events that are co-located (happen at the same point in space) are agreed upon by everyone. (what the readings are on the clocks of the two ships when they pass each other, or whether or not two objects collide or not, etc.)
     
  13. OnlyMe Valued Senior Member

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    The constantcy of the speed of light, in a vacuum, is drawn from experiments that demonstrate that two observers in relative motion to one anther always measure the speed of light to be the same.

    If you are in a space ship traveling at 1/2 the speed of light and shine a flash light from back to front, i.e. In the direction of motion it will not take twice as long the hit the front of the spaceship as if tye ship were not in motion. It does not slow down just because you are moving.



    If independent objects are sharing the same frame of reference they will not "experience" length contraction. If that frame of reference is in motion it would be length contracted in the line of motion for both observers, they just would not experience it differently than being at rest.
     
  14. Emil Valued Senior Member

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    2,801
    Then why do you need the second real object?
    Consider an imaginary object and apply the length contraction to the space.
    If you do not agree, I gives you another idea.
    On your direction of travel you find somewhere in the space an object whose speed it convenient, so you can apply the length contraction to the space.
    And so you tricked physics, because you do not want to go up there, but you will stop soon, because your target was an object closer but whose speed was not convenient.
     
  15. Emil Valued Senior Member

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    2,801
    And how much must be minimum distance between events, so you can apply The Relativity of Simultaneity.
    It may be a micron?
     
  16. Janus58 Valued Senior Member

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    2,394
    You don't need any physical objects at all. You can just use coordinate systems and points in space. It is just easier to visualize if you use objects as a type of "place holder"
    This makes no sense what-so-ever. The distance between two points for you is what you measure them to be. It does not matter the distance is according to some other frame or object. If I am moving between two point, I measure the distance between them as being a certain distance. Someone at rest with respect to these points will measure it as being a longer distance, and someone moving between the point at a greater realative speed will measure it as being shorter, but neither of these measurements in those frames effect how far part I measure them. The only way that I can change the distance between those two point by my measurement is to change my speed relative to them.
     
  17. Me-Ki-Gal Banned Banned

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    Sounds like we are trapped in an expanding bubble . Hey maybe free will is an illusion and there are other bubbles that react just like we have

    I like your mangling , but I would being an mg , Lets go mangle the world
     
  18. Janus58 Valued Senior Member

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    2,394
    There is no "minimum", but the difference in simultaneity decreases with distance.

    The difference is found by:

    \(\frac{vx}{c^2}\)
    where x is the distance separating the events.
    So if v is 0.5c and x is one 1 million km, the difference is 1.667 sec.

    At the same speed, and a distance of 1 micron, the difference is 1.667 femtoseconds (1667/1,000,000,000,000,000,000 of a second)
     
  19. Emil Valued Senior Member

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    2,801
    This example is very important because it demonstrates that the relative speed between two objects may be higher than the speed of light, even if the velocity of the object not exceeded the speed of light. This means that Lorentz transformation can not be applied between these two objects.
    I believe that these aberrant responses are your own interpretations of Special Relativity.
    If I'm wrong please give a link.
    For me it is an obvious example for an aberrant interpretation of Einstein's Theory of Relativity.
    Like I said: time is absolute and universal and can exceed the speed of light.
    Two events happen simultaneously, are simultaneous, irrespective of our perception.
    For that we are in a real world and not in a dream, where anything can happen.
    But I recognize your right to believe in what you want.

    Einstein:
    "You do not really understand something unless you can explain it to your grandmother."
    "If you can't explain something simply, you don't know enough about it."
     
    Last edited: Apr 1, 2011
  20. OnlyMe Valued Senior Member

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    Great quote!

    I wish more of those on the leading edge of science really understood what they are talking about! That way perhaps I would also.
     
  21. AlphaNumeric Fully ionized Registered Senior Member

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    6,702
    While I agree that researchers could do with being better at explaining their work and more people on the street should know more physics I think the quote about explaining stuff to your grandmother shouldn't be applied to everything, it has its limits.

    For instance, I can explain the stuff my research involved on a very superficial level to almost anyone. However, such an explanation would not provide anyone with any insight in how I reached the conclusions I did, what methodologies I used, how the details fit together. If, after hearing the superficial explanation, someone asks "But how did you prove such a result?" then they are now explicitly asking about details and by their very nature details of science require some scientific knowledge and thus cannot be explained just off the bat to anyone, grand mothers included.

    Then there are some things which are by their very nature extremely abstract. Once you scratch the surface of what my thesis pertained to you're into the realm of highly mathematical things which have no everyday analogies or examples. No one in my office understood what I did and they were all theoretical physicists too. Hell, BenTheMan and I worked in extremely similar areas (both of us used phrases like 'flux compactification' with abandon) but I don't think he understands the details of what I did, nor I him.

    To give another example a professor at Cambridge once talked about how when applying for a research position often the interview panel will involve people not in your area, or even subject (ie a historian on a panel to appoint a mathematician) and they often ask things like "So can you explain a little about your specific research, in a way that I would understand?". You should never say "No", it makes you sound arrogant and it shows you can't explain your work in plain terms. They only gave a job to one person who said that and he was Andrew Wiles, the guy who solves Fermat's Last Theorem with mathematics he developed himself which less than a dozen people in the world really understand. He, obviously, is an exception.

    Research is about pushing the understanding of mankind as a whole, being able to explain bleeding edge research to a layperson is therefore going to devoid of detail and any one asking for detail is going to have to be willing to put some effort in to understand said detail.
     
  22. Janus58 Valued Senior Member

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    2,394
    From:
    http://www.bartleby.com/173/9.html

    "Are two events (e.g. the two strokes of lightning A and B) which are simultaneous with reference to the railway embankment also simultaneous relatively to the train? We shall show directly that the answer must be in the negative." (italics mine)

    This directly from Relativity: The Special and General Theory. by none other than A. Einstein.

    I really find it hard to believe that anyone could have done any research of any depth into Relativity without coming across this concept (Along with time dilation and length contraction, one of the three "legs" of Special Relativity.

    We do live in a real world, one ruled by Relativity, and though those rules may seem counter-intuitive, they are real just the same. This is not [/i]my belief[/i], this is what the theory and the collected evidence says.

    I
    The kicker is that the person to which it is being explained must put some effort into following the explanation, which sometimes requires them to put aside ideas that they previously believed in. With Relativity this includes giving up the idea of absolute time and space.
     
  23. OnlyMe Valued Senior Member

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    You are absolute correct in this. There are things that grandmother shouldn't know.

    Another atempt at humor.
     

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