PD
Posts:
2,970
Registered:
5/25/05
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Re: Preferred Frame Theory indistinguishable from SR
Posted:
Jul 10, 2010 12:13 PM
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On Jul 9, 7:05 pm, kenseto <kens...@erinet.com> wrote:
> On Jul 9, 3:02 pm, PD <thedraperfam...@gmail.com> wrote:
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> > On Jul 8, 8:59 pm, colp <c...@solder.ath.cx> wrote:
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> > > On Jul 9, 10:09 am, PD <thedraperfam...@gmail.com> wrote:
>
> > > > On Jul 7, 5:43 pm, colp <c...@solder.ath.cx> wrote:
>
> > > > > On Jul 7, 8:52 am, PD <thedraperfam...@gmail.com> wrote:
>
> > > > > > On Jul 6, 3:03 pm, colp <c...@solder.ath.cx> wrote:
>
> > > > > > > On Jul 7, 3:07 am, PD <thedraperfam...@gmail.com> wrote:
> > > > > > > > The problem, you see, is that the comic-book statement you are using
> > > > > > > > as your launching point belongs in COLP's Oversimplified Relativity.
>
> > > > > > > It's not a comic book statement any more than Einstein's statement
> > > > > > > that a moving clock lags behind a stationary clock is a comic book
> > > > > > > statement.
>
> > > > > > Not so. Einstein's statement included things that you have discounted.
>
> > > > > I haven't discounted them.
>
> > > > > > For example, he makes note of specific events, rather than just making
> > > > > > the general statement that "moving clocks" run slow.
>
> > > > > The description of the specific events only serves to illustrate that
> > > > > it is the moving clock that runs slow compared to the stationary
> > > > > clock.
>
> > > > Then you have misunderstood what he said. The EVENTS do more than
> > > > that.
>
> > > How, exactly?
>
> > > > > > Furthermore, he
> > > > > > makes EXPLICIT mention of the statement that the clocks at points A
> > > > > > and B are initially synchronized IN THE K FRAME.
>
> > > > > Assuming that they weren't synchonized in my general description of
> > > > > "the moving clock runs slow" would be arbitrary and illogical.
>
> > > > They are synchronized in the K frame. They are not synchronized in the
> > > > K' frame. This is essential and cannot be dismissed.
>
> > > If they are not synchronized in the K' frame, then the K frame becomes
> > > the preferred frame of reference, which contradicts Einstein's first
> > > postulate.
>
> > Why? Two clocks being synchronized or not synchronized do not
> > determine a preferred frame.
> > A preferred frame is one in which the LAWS OF PHYSICS are different
> > than in other frames.
>
> In that case what are the differences in the LAWS OF PHYSICS between a
> preferred frame and an inertial frame?
Well, that would be the point. We've never discovered a frame in which
the laws of physics are different.
> For eample: Does a preferred
> observer's clock runs at a different rate than an inertial SR
> observer's clock....does it runs fast or slow??? Failure to answer
> this question will mean that you are trying to bull shit your way out.
Ken, the rate of a clock is not a law of physics.
It might help to learn the meaning of terms used in physics before
trying to discuss them.
Here's one to learn: "law of physics".
>
> Ken Seto
>
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>
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> > Perhaps the difficulty is in your understanding of what a preferred
> > frame means.
>
> > > > > Remember I was talking about _the_ clock, in reference to the moving
> > > > > clock described in "Electrodynamics of Moving Bodies", not to a clock
> > > > > in an arbitrary system.
>
> > > > I understand that completely. There are two clocks involved here: One
> > > > that moves from A to B and one that remains at B. There is a frame K
> > > > in which points A and B are at rest, and there is a frame K' in which
> > > > points A and B are moving and the first clock above is at rest.
>
> > > Yes, I agree.
>
> > > > > > A contradiction would
> > > > > > arise by making the clock at B the moving clock only if the clocks are
> > > > > > claimed to be intially synchronized also in the K' frame -- but they
> > > > > > are NOT, and this is the essential detail that you have missed.
>
> > > > > No, it isn't a missing detail, it is an implication of Einstein's
> > > > > first postulate of relativity.
>
> > > > WHAT is an implication of the first postulate? That they are also
> > > > synchronized in K'? No.
>
> > > The implication is that if there is no preferred frame of reference
> > > then predictions made in one inertial frame will be just as valid as
> > > predictions made in any other inertial frame, and if it is possible to
> > > synchronize clocks in one inertial frame them it is possible to
> > > synchronize clocks in any other inertial frame.
>
> > It is of course possible to resynchronize the clocks in K'. However,
> > this will mean that they are no longer synchronized in K. What is true
> > is that there is no way to have them be synchronized in BOTH K and K'
> > at once.
>
> > Now, again, if you are reading the principle of relativity to say that
> > "Clocks that are synchronized in one inertial frame are also
> > synchronized in other inertial frames," then you do not understand
> > what the principle of relativity says.
>
> > The principle of relativity does NOT say that an observation in one
> > inertial frame will be identical to an observation in any other
> > inertial frame. For example, an object that is stationary in one
> > inertial frame would not be expected to be stationary in other
> > inertial frames. Nor does it mean that the values of physical
> > quantities are the same in all inertial frames. For example, the
> > momentum of an object or even a closed system in one inertial frame is
> > not the same as that same quantity in other inertial frames.
>
> > The principle of relativity explicitly makes a statement about the
> > form of the LAWS OF PHYSICS in different inertial frames being
> > identical.
>
> > So, it appears that so far, we've had to explain to you what a
> > preferred frame means, and what the principle of relativity means.
>
> > > > > Here is Einstein's description of the clocks:
>
> > > > > "If at the points A and B of K there are stationary clocks which,
> > > > > viewed in the stationary system, are synchronous; and if the clock at
> > > > > A is moved with the velocity v along the line AB to B, then on its
> > > > > arrival at B the two clocks no longer synchronize, but the clock moved
> > > > > from A to B lags behind the other which has remained at B ..."
>
> > > > > Let us call the moving system K', in which the moving clocks at A' and
> > > > > B' are synchronized for an observer in K'. The stationary system K
> > > > > also has two clocks, but these two clocks are synchronized for an
> > > > > observer in K. Frames K and K' move at a constant velocity with
> > > > > respect to each other.
>
> > > > > If there is no preferred frame of reference then there is no reason
> > > > > why the clocks at A' and B' cannot also be synchronized for an
> > > > > observer in K', just as the clocks at A and B are for an observer in
> > > > > K, due to the symmetry of the two frames and their respective clocks.
>
> > > > Yes, that is true but the clock that is synchronized with B in K will
> > > > not initially show the same time as the clock that is synchronized
> > > > with B in K'.
>
> > > Are you saying that the clock at A in K (that is synchronized with the
> > > clock at B in K) will not initially show the same time as the clock at
> > > A' in K' (that is synchronized with the clock at B' in K'?
>
> > That's right, if B is synchronized with B'. Note that you do not need
> > these two extra clocks. Let's stick with the two clocks in Einstein's
> > statement, so I can explain exactly what he is saying.
>
> > > > Now YOU are the one that is adding things beyond what Einstein
> > > > actually said.
>
> > > What I am adding (two more clocks in K') does not change Einstein's
> > > postulates. Neither does making predictions from the point of view of
> > > an observer in each frame affect the postulates.
>
> > > > There are only TWO clocks in Einstein's paragraph. One that moves from
> > > > A to B and one that remains at B. In the frame K, the clocks are
> > > > synchronized when the clocks are at A and B.
>
> > > Right.
>
> > > > In the frame K' that you
> > > > propose, those same two clocks are not synchronized when the clocks
> > > > are at A and B.
>
> > > I'm not talking about the same two clocks. I'm talking about two
> > > frames which are the same in all respects except for their relative
> > > motion (in order to establish symmetry). Thus in the K frame the clock
> > > at A' moves from A to B. When point A = point A', the clocks at these
> > > points are synchronized, just as Einstein's clock at A was
> > > synchronized with B before it moved towards B.
>
> > > Looking at the situation from the point of view of an observer in K',
> > > the clock at B moves from B' to A'.- Hide quoted text -
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