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What's wrong with this thinking?

  1. Dec 16, 2005 #1
    Before I even venture into the maze, a question:

    what I'm meaning to do, is post a 'personal theory about relativity' that some guy told me. Now, it's quite ludicrous, even though the dear man tries to stick to the right principle. Which makes it hard for me, who is not really interested in relativity, to point out where the flaw of his argument lies.

    So: the purpose of this post would not be to vent a personal theory - but to rebute it.

    Is this allowed in this forum? Can I proceed? If not, a quick notice is enough, then I'll delete this post myself.
     
  2. jcsd
  3. Dec 16, 2005 #2

    Pengwuino

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    I doubt the mods would see anything wrong with it since you're not pushing a theory, you're really only asking whats wrong with a certain way of looking at something.
     
  4. Dec 20, 2005 #3

    -Job-

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    Expect "passionate" replies. :)
     
  5. Feb 10, 2006 #4
    Alright, so here's the theory:

    Bear with me, because it's hard to state his theory in concrete facts... I had a whole discussion with him, but he really didn't manage a clearer view. Also I edited his message a bit, so the more tiring and less relevant segments of the discussion are cut out of the message.
    Where the meaning of the sentences is vague, this is probably due to my bad translations,- so do ask for clarification where it is needed. I've also had more talks with this person than I've included here, so maybe there's some extra feedback I can give if necessary.

    Allons...

    Speed of light ... 0

    Although in physics it is still assumed that the speed of light is the highest attainable speed, I suspect it to be the opposite. According to my view, the speed of light is the absolute zero of time and movement. I believe that I have a couple of arguments that support my views, and the flaws found in current science.

    1. Time and space

    He starts by introducing basic relativistic concepts, space-time as a four dimensional continuum. He wonders whether time can exist if the universe is completely empty (ie. matterless). I don't think it's an essential part of his thinking (his reasoning ends with the assertion of time and space always being in existence together, so that's nothing special).

    Everyone knows that space is nothing else than a distance. We measure distances by choosing two points and calculating the distance in between these points. These points are then for instance different masses. A distance from your house to the supermarket, is in essence nothing different from the distance between your front door and the front door of the supermarket (so he implies that the distance between physical objects is measured as being the distance between the points that represent these physical objects in a modelled, mathematical space.).

    This is where it gets odd.
    Starting from the moment you want to go from your house to the supermarket, you have a certain road to travel. Even though nobody consciously recognizes this, a travelled road only consists out of travelled time. This is because, without time, you cannot travel a road. (Having trouble translating a 'travelled road', a trajectory, into English here... any suggestions?.)
    You do move over a road, but the space between you and the supermarket really is nothing different than the time you can travel. Whether you will effectively do this is not important.
    When distances exists, time exists as well. The distance from the earth to the moon eventually exists solely out of the time needed to get from the earth to the moon.

    So from this one could conlcude that time and space are essentially the same. Every distance represents a piece of time wherein you have determined the amount of time needed to travel this distance. At the moment it's believed that the speed of light (about 300000 km/s) is the highest attainable speed, from which you can derive that the minimal 'time' between us and the moon, which is also about 300.000 km, is 1 second. So if you would fly to the moon with the speed of light, this will take you 1 second and so you would be 1 second older.
    Your travelled road will then be 300.000 km and 1 second.

    Now all of the time we move with different velocities (In Dutch, there's no distinction between speed and velocity.. I apologize for a wrong use of the term.), or even stand still ; but time always seems to go by with a fixed speed. We might feel that an hour lasts longer or shorter, but a clock will not pay attention to your feelings. Still time may indeed run faster or slower. This has been shown in diverse experiments.

    He then talks about these experiments, including the 'fly around the earth' experiment.

    So what was the conclusion? The clock that flew along the rotary direction of the earth ran ahead on the fixed clock, and the clock that flew contrary to the rotary direction of the earth ran behind. Imagine the earth as a rotating disc and visualize a fixed point somewhere at the edge of this disc. 1 full rotation of the disc then represents 40.000km.

    Now 1 rotation lasts exactly 24 hours and you let those two clocks fly in opposite direction. These clocks move with exactly the same speed, and both take 24 hours to travel 40.000 km.
    The clock that moves along with the rotary direction of the disc travels 40.000 km in 24 hours in reference to the fixed clock, plus the 40.000km that the fixed clock travelled. So the total distance is 80.000km. The other clock does 40.000 km in reference to the fixed clock, minus the travelled road of the fixed road. So in fact it has travelled 0km.

    So this shows that time passes less quickly when you travel less kilometers. Time and travelled road are thus closely connected. Time will run slower when you travel less kilometers.

    Eh.. what?..

    This contradicts the relativity theory because this theory shows that time passes slower when you travel more kilometers.
    At the speed of light, you travel a lot of kilometers per second, and so time should be practically standing still. I wonder what kind of speed a foton would measure because for a foton no time has passed after 300.000km. When a second passes for a foton, it would have travelled an infinite amount of kilometers. Which would mean the actual light speed would be far higher than we think.


    I'll do the rest of his theory some other time... If I understand it correctly, his point is that we should choose the speed of light to be zero, because it can count as an absolute reference point, ... in another discussion he mentions that no matter ever stands still (because of vibrations etc.), and thus there is no 'zero speed' (which is pretty evident, because if there were zero speed, then also an absolute zero temperature would be attainable).
     
  6. Feb 10, 2006 #5

    pervect

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    If I were you, I would ask this person how he explains the fact that measurements (such as the lifetime of muons) appear to support relativity and not his theory. (I.e. muons live longer, and reach the Earth from the upper atmosphere. Muons in accelerators are also noticed to have longer lifetimes).

    I don't really follow his logic, BTW. But complaining about "poorly-motivated philosophical rambling" probably won't win any brownie points with this person, (but that's how I'd summarize my percpetion of his argument).
     
    Last edited: Feb 10, 2006
  7. Feb 10, 2006 #6
    Providing that we're ignoring accelerations (which I will assume for the rest of this post) I can agree with this statement. If I'm traveling at a constant velocity from one point to another the only difference between those two points in my reference frame is the ammount of time it took for them to pass me. I can calculate a distance (spacetime interval) assosciated with my travel between these two points and all observers will agree upon that interval, even observers who thought that I moved through both time and space to reach the points.

    No, the closer you get to 300.000 km/s the closer the moon will get to the earth and it will take less and less time, approaching zero, for you to reach the moon.

    Neither one of the ships went anywhere. Run as many experiments as you like in either one of the ships, you'll never be able to say "I traveled x kilometers" unless x is zero. The only meaningful quantity here is the instantaneous observed velocity between the ship and the ground observer.
     
  8. Feb 10, 2006 #7

    pervect

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    Well, let me try and say something useful rather than just grumbling.

    I would call a "road" a curve, which is a path through space-time. Cuves can be specified in many ways, one of the standard ways is via four functions:

    t(lambda), x(lambda), y(lambda), z(lambda)

    which give the coordinates (location on the curve) of a moving object/observer as a function of some parameter lambda.

    The parameter "lambda" may be (but is not required to be) the "proper time" of the travelling observer, i.e. what the observer reads on his "wristwatch".

    We draw a distinction between "coordinate time" and "proper time" here. Coordinate time is the time coordinate 't', assigned to an event, while "proper time", tau, is what the travelling observer reads on his wristwatch (i.e a clock that he carries along with him on his journey).

    What SR basically says is that the quantity

    [itex]
    c^2dt^2 - dx^2 - dy^2 - dz^2
    [/itex]

    called the Lorentz interval, is a universal invariant for any observer in an inertial frame.

    Hopefully the idea of "inertial frames" can be directly imported from Newtonian physics.

    As a consequence of this, the manner in which one transforms coordiantes between different inertial frames is not the familiar "Gallilean transformation", but rather the "Lorentz transformation".

    The Gallilean transformation is

    x' = x - vt
    t' = t

    and is valid for Newtonian physics.

    The Lorentz transformation is

    [itex]x' = \gamma(x - v \, t)[/itex]
    [itex]t' = \gamma(t - v \, x/c^2)[/itex]

    where [itex]\gamma = 1/\sqrt{1-(v/c)^2}[/itex]

    and replaces the Gallilean transformation when special relativity (rather than Newtonian physics) is used.

    More on the transformations can be read at
    http://hyperphysics.phy-astr.gsu.edu/HBASE/relativ/ltrans.html

    [total re-write for clarity]
    Consider two events (in a 2-d space-time, for simplicity)

    Event 1 is at (x1,t1)
    Event 2 is at (x2,t2)

    Consider the SAME two events in a different 'frame'of reference;, the "primed" frame, (which must be an inertial frame of reference)

    Event 1 is at (x1', t1')
    Event 2 is at (x2', t2')

    According to to the Gallilean transformation, the time between the two events will be invariant, i.e. the same for all observers in inertial frames.

    This is because t2' - t1' = t2 - t1

    This is no longer true in SR. In SR, what is invariant is the Lorentz interval, which is

    [itex]c^2(t2' - t1')^2 - (x2' - x1')^2 = c^2(t2-t1)^2 - (x2-x1)^2 [/itex].

    This can be seen by direct substitution of the defintion of the Lorentz transform, and a lot of mathematical substitution

    i.e x2' is defined by the Lorent transform in terms of (x2,t) by the equation

    x2' = [itex]\gamma (x2 - v t2)[/itex]

    use the similar defintions to replace x1', t2', and t1' with unprimed variables, and simplify the resulting expression.
     
    Last edited: Feb 10, 2006
  9. Jul 30, 2006 #8
    perverse, thank you for that summary, but it's not really any help here. This person understands the postulates of SR, and understands the formula's as well. Point is, he tries to do magic with relative viewpoints, and it doesn't make any sense.

    He returned, translated his stuff in English, and made it more concise. I'll give you a second run below.

    Just beforehand, I need to understand some of the stuff said above:
    dicerandom:
    1. "No, the closer you get to 300.000 km/s the closer the moon will get to the earth and it will take less and less time, approaching zero, for you to reach the moon."

    huh? The moon and earth will get closer how?


    And now for the madman:

    Let's just ignore the mumbojumbo and stick to the "science". What's wrong this thinking?
     
  10. Jul 30, 2006 #9

    ZapperZ

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    I think this is where we have to draw the line. I'm not going to delete this, but unless someone has something important to add, this thread is done. However, I would like to point out that we do not entertain crackpottery, even when one is trying to debunk such a thing. You could have easily just quoted the "science" part without advertizing the crackpottery associated with it.

    There have been many people who tried to get around our guidelines by pretending to want to ask and wanting to know what's wrong with so-and-so posts. We have no way of distinguising one from the other, and thus, we make a blanket policy of NOT allowing such a thing.

    Zz.
     
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