Re: IRT: A New Theory of Relativity

From: kenseto (kenseto_at_erinet.com)
Date: 02/02/05 

Date: Wed, 02 Feb 2005 18:22:04 GMT

"Jesse Mazer" <vze2ztqw@mail.verizon.net> wrote in message
news:42002F0E.4090204@mail.verizon.net...
>
>
> kenseto wrote:
>
> >"Jesse Mazer" <vze2ztqw@mail.verizon.net> wrote in message
> >news:41FC2F54.80901@mail.verizon.net...
> >
> >
> >>kenseto wrote:
> >>
> >>>>Lorentz may have formulated them this way, but Einstein showed that if
> >>>>each observer measures coordinates in terms of rulers and clocks at
rest
> >>>>relative to himself, and each observer synchronizes his own set of
> >>>>clocks based on the assumption that light travels at the same speed in
> >>>>all directions in his own frame, then the Lorentz transformation will
> >>>>work for *any* two frames, regardless of their velocity relative to
the
> >>>>ether (which renders the ether superfluous).

The LT works only if the state of the absolute motion of the observer is
lower than that of the observed frame. It doesn't work if the state of
absolute motion of the observer is higher than that of the observed frame.
For example A and B are in the same frame and B accelerated away and becomes
inertial again. The LT will work from A's point of view because he has a
lower state of absolute motion than B. However the LT will not work from B's
point of view because B has a higher state of absolute motion than A.

> >>
> >>
> >
> >So why I am wrong? You are saying the same thing.
> >
>
> No, you are saying that Einstein assumed the observer using the Lorentz
> transformations was in a state of rest relative to the ether, I am
> saying you are wrong, in SR the Lorentz transformation will work for
> transforming between *any* two inertial coordinate systems, even if you
> assume both are in motion relative to the ether,

This is not true. In this case, the LT works only for the inertial
coordinate system that has a lower state of absolute motion.

>or if you are
> transforming from the coordinates of an observer in motion relative to
> the ether into the coordinates of one at rest relative to the ether.

This is not true. The ether frame clock has the fastest clock rate by
definition. An observer moving in the ether can't say that the ether frame
clock is running slow compared to his clock.!!!!!
>
>
> >
> >
> >
> >>It works out this way because
> >>different observers define simultaneity differently.
> >>
> >>
> >
> >IRT disagrees with this assertion. This assertion violates the isotropy
of
> >the speed of light in all inertial frames.
> >
>
> No it doesn't. The relativity of simultaneity is based on the assumption
> that each observer synchronizes his clocks by assuming light moves the
> same speed in all directions in his own frame. If you actually try
> plugging numbers into the Lorentz transformation, you'd see that if the
> distance/time between two events in one frame is c, then it must also be
> c in the other frame, regardless of the spatial positions of the two
events.

NO....RoS is derived from the bogus assumption that the train observer is
moving wrt the light fronts and the track observer is not. The reason why
this assumption is bogus because it assumes that the direction of absolute
motion of the train is parallel to the track. On earth the direction of
absolute motion for all objects is in the vertical direction. BTW, that's
the reason for the MMX null result. The MMX will show a positive result if
it is oriented with the plane of the arms in the same vertical direction of
the absolute motion of the apparatus. This way different orientations of the
arms will produce different light path lengths and thus the positive
results.
>
> For example, suppose that in frame A a supernova goes off at position
> x=0 light years at time t=0 years, and that light from the nova is
> detected by two telescopes--the first is at position x = 1 ly and it
> detects the light at time t=1 y, and the second is at position x= -1 ly
> and it also detects the light at time t=1 y. You can see that in A's
> frame the light moved at a rate of c = 1 ly/y in both directions. So how
> will this look in the frame of an observer B moving at v=0.6c relative
> to A? The Lorentz transformation equations are:

>
> x'=gamma(x - vt)
> t'=gamma(t - vx/c^2)
>
> where gamma = 1/squareroot(1 - v^2/c^2). So, plugging these numbers in:
>
> x=0, t=0 in A's frame converts to x'=0, t'=0 in B's frame.
>
> x=1, t=1 in A's frame converts to x'=1.25(1 - 0.6*1)=0.5, t'=1.25(1 -
> 0.6*1/1) = 0.5 in B's frame
>
> x=-1, t=1 in A's frame converts to x'=1.25(-1 - 0.6*1)=-2, t'=1.25(1 +
> 0.6*1/1) = 2 in B's frame.
>
> So in B's frame, the light beam moving right took 0.5 years to reach the
> telescope on the right, which was 0.5 light years from the origin of B's
> coordinate system at that moment; the light beam moving left took 2
> years to reach the telescope on the left, which was 2 light years from
> the origin of B's coordinate system at that moment. So, B also saw the
> light travelling at a rate of 1 light year/year in both directions,
> despite the fact that he did not agree with A that the light beams
> reached both telescopes simultaneously.

B must use his own clock and rod to determine the locations and the relative
velocity of the two telescopes wrt him. Then use the LT to determine if the
light fronts will arrive at the telescope simultaneously. You calculations
using A's measurements is not valid from B's point of view.

>
> >
> >
> >These diagrams assumes rod contraction and time dilation in the moving
syate
> >m. Clearly this is not correct if the observer who is doing the moving
and
> >the observed relative motion is due to the observer's motions.
> >
>
> No they don't assume that, they can be used to *prove* that. Let's say A
> is in a state of absolute rest and B is in a state of absolute motion,
> OK? Then if the distance between markings on B's ruler shrinks by 1/2,
> and the ticks of B's clocks slow down by 1/2, and B synchronizes his
> clocks by assuming light moves at the same speed in both directions in
> his frame, then do you agree that
> http://www.jessemazer.com/images/RulerAFrame.gif shows which ruler
> markings on B will line up with which markings on A at any given time in
> A's frame, and what the clock on B's ruler at that marking will read at
> the moment they line up?
>
> If so, you can draw the diagram for how things look in B's frame just by
> assuming he must get the same answers about what positions/clock
> readings on his ruler match up with what positions/clock readings on A's
> ruler. For example, if you look at the middle part of the diagram in A's
> frame, you see that when the clock at the 0-meter mark on ruler A reads
> "1 microsecond", it is lined up with the -519.3-meter mark on ruler B,
> and the clock at that mark on ruler B reads "2 microseconds". So do you
> agree that when we switch to ruler B's frame, this *must* mean that at a
> time of 2 microseconds in B's time coordinate, the -519.3-meter mark on
> his ruler must be lined up with the 0-meter mark on ruler A, and the
> clock at that mark on ruler A *must* read "1 microsecond"? The only
> assumption here is that B defines his own time-coordinate by readints on
> his own clocks, and that both frames must agree on local events (ie if a
> photo is taken of a particular mark on one ruler passing a particular
> mark on another, they can both look at the photo and agree on what the
> clock mounted on that mark read at that moment). Just by looking at what
> markings/clock readings line up in A's frame, you can construct the
> diagram at http://www.jessemazer.com/images/RulerAFrame.gif of what
> things look like in B's frame, without making any additional assumptions.

I have no idea what you are talking about.
>
>
>
> > So what is
> >your point? IRT says a rod moving wrt the observer is contracted (or a
> >longer light path length) but it also says that a rod moving wrt the
> >observer is expanded (or shorter light path length).
> >IRT says a cl*** moving wrt the observer is running slower than the
> >observer's clock but it also says that a clock moving wrt the observer is
> >running fast compared to the observer's clock.
> >
> >
> >>Do you agree that in the first diagram corresponding to ruler A's
> >>reference frame, all of ruler B's clocks are ticking at half the correct
> >>rate and all the markings on ruler B are squished to half the correct
> >>length?
> >>
> >>
> >
> >You already assumed this when you make the iagrams so what is your point?
> >
>
> No, all I assumed is that if an observer in the A-frame sees a
> particular clock of his line up with a particular clock on ruler B at a
> particular moment, then whatever the readings on these two clocks as
> they pass next to each other, then these same two clocks must also show
> the same readings as they pass each other in the B-frame. Do you
> disagree with that assumption?

You assumed that the clock at the B ruler is ticking at half of the rate of
A's clock. This assumption is followed from that A is at a lower state of
absolute motion. The fact that A and B agree that their clocks show the same
readings when they pass next to each other is irrelevevant.

>Or do you agree with it, but disagree
> that http://www.jessemazer.com/images/RulerAFrame.gif shows how things
> will line up in the A-frame, even if you assume A is a state of absolute
> rest?
>
>
>
> >
> >
> >
> >>Do you also agree that in the second diagram corresponding to
> >>ruler B's reference frame, all of ruler A's clocks are ticking at half
> >>the correct rate and all the markings on ruler A are squished to half
> >>the correct length? Do you agree that the way the readings on one
> >>ruler/clock system match up to the readings on the other ruler/clock
> >>system in these diagrams matches the predictions of the Lorentz
transform?
> >>
> >>
> >
> >Sure it matches the LT but it is incomplete. Why ? becasue it excludes
the
> >possibility that it was the observer who is at a higher state of absolute
> >motion than the observed frame.
> >
>
> Nope, the LT works even if you believe in a state of absolute rest
> defined by the ether rest frame, and even if neither observer is at rest
> relative to the ether, or even if you want to transform *from* the
> coordinates of an observer in motion relative to the ether *to* the
> coordinates of one at rest relative to the ether. The only assumptions
> needed are:
>
> 1. Rulers moving at velocity v relative to the ether shrink by
> squareroot(1 - v^2/c^2), and clocks moving at velocity v relative to the
> ether extend their ticks by a factor of 1/squareroot(1 - v^2/c^2).

This is true only from the ether frame point of view. But in real life both
the observer and the observed frame are in different states of absolute
motion. Therefore the observer must use the IRT. That means that the
observed ruler is shrank by 1/gamma or expanded by gamma and the tick rate
of the observed clock is running at a rate of 1/gamma or gamma compared to
the observer's clock..
>
> 2. In the rest frame of the ether, light travels at c in all directions.

This is true in all inertial frames. The reason is that the speed of light
is a constant math ratio in all frames as follows:
Light path length of rod (299,792,458m)/the absolute time content for a
clock second co-moving with the rod.
>
> 3. All observers, even those in motion relative to the ether,
> synchronize spatially separated clocks using the assumption that light
> travels at the same speed in all directions *relative to themselves*.

Yes.
>
> 4. Each observer defines their coordinate system in terms of local
> readings on a network of rulers and clocks which are at rest relative to
> themselves, and with the clocks synchronized using assumption #3

There is no clock synchronization required.
>
> 5. observers in different frames must agree on local events, like the
> readings on each of their clocks when the two clocks pass right next to
> each other.

I don't see your point on this.
>
> If all these assumptions hold, you can prove absolutely that the LT will
> accurately convert between the coordinate systems of *any* two
> observers, regardless of how each one is moving relative to the ether.

These assumptions do not hold for the reasons stated above.

> Do you need me to show you this proof, or do you accept that this does
> follow from these assumptions, but you just disagree with one or more of
> the assumptions?

I disagree with assumption #1. That's the reason why SR is incomplete and
that's why I invented IRT.
>
>
> >
> >
> >>
> >>
> >>>
> >>>
> >>I'm asking about how the PoR works in SR, not in your theory. Do you
> >>agree that the coordinate system assumed in the Lorentz transformation
> >>in SR is not based on "light path length",
> >>
> >>
> >
> >It is based on light path length. Why? Because rod contraction is the
same
> >as longer light path length with the rod remaining at the same physical
> >length.
> >
> >
> >
> >>but just based on the
> >>measurements of rulers and clocks at rest with respect to each observer,
> >>with each observer synchronizing his clocks by making the assumption
> >>that light travels at the same speed in both directions relative to
> >>
> >>
> >himself?
> >
> >I don't understand why an observer need to synchronized any clcoks at
all.
> >All he need is one cl*** to make time interval measurements.
> >
>
> Because the point of an observer's own time-coordinate is to label the
> moment the event actually happened, not the moment I saw the event.

The time coordinate can be determined by the time of the moment when you saw
the event less the time for light to traverse the distance between the event
and you.

>If I
> only have one clock, I can only use that clock to find the time I
> actually saw light from an event, not the time the event actually
> happened.

The time the event actually happened is the time that you saw the event less
the time that light needed to traverse the distance between you and the
event.

>Of course, if I know the distance the event was when it
> happened (as measured by a ruler at rest relative to me), I can
> *calculate* the time the event happened by dividing this distance by the
> speed of light, then subtracting the resulting time interval from the
> time when I saw the light from the event. But if I have a network of
> synchronized clocks throughout space, I don't need to do any
> calculations, I can just look at the reading on the clock of mine which
> was right next to the event at the moment it happened. In a way it
> doesn't matter which method I use, because both methods will result in
> my assigning the same time-coordinate to the event--if you agree that
> they both give the same answer, are you willing to assume *for the sake
> of the argument* that we use the synchronized-clock method rather than
> the (time I saw event) - (distance of event when it happened)/c
> calculation?

NO, I don't agree. Your net work of synchronized clocks are imaginary. You
can't read the clock reading of that imaginary clock next to the supernova.
>
>
>
> >
> >
> >
> >
> >>Again, look at the diagrams
> >>I drew above to see how this works out. For example, in the diagram
> >>showing ruler A's frame at
> >>http://www.jessemazer.com/images/RulerAFrame.gif , look at the clock on
> >>the "-346.2 m" mark on ruler B. You can see that in the top part of the
> >>diagram, this clock reads a time t'=1 microsecond and is lined up with a
> >>clock on ruler A reading t=0 microseconds; then in the bottom part of
> >>the diagram, this clock reads a time of t'=2 microseconds and it's lined
> >>up with a clock on ruler A reading t=2 microseconds. So in ruler A's
> >>frame, this clock has only ticked forward 1 microsecond while 2
> >>microseconds have actually passed according to A's time-coordinates.
> >>
> >>
> >
> >All this means is that a micro second in A's frame does not correspond to
a
> >microsecond in B's frame. However, in terms of absolute time content
> >1 microsecond in B's frame=2 microseconds in A's frame.
> >
>
> Only if you assume A is in a state of absolute rest!

But that's what you were assuming when you said that 2 microseconds of A's
clock will fit into 1 microsecond of B's clock.

>If you assume it is
> B who is in a state of absolute rest, then 1 microsecond in B's frame =
> 1/2 microsecond in A's frame, in terms of absolute time.

So what is your point??

>But either way,
> both A and B will *measure* the other one's clock to be ticking at half
> the rate of their own clock,

No it doesn't.

>even if you believe one of them is making
> "inaccurate" measurements in terms of absolute space and time. Again,
> this follows from the 5 assumptions I outlined earlier.
>
>
>
> >
> >
> >>But now look at the same situation in ruler B's frame, in the diagram at
> >>http://www.jessemazer.com/images/RulerBFrame.gif ...if you look at the
> >>same clock on ruler B at "-346.2 m" in the middle and bottom part of the
> >>diagram, you again see that when this clock reads t'=1 microsecond, it's
> >>lined up with a clock on ruler A that reads t=0 microseconds (the one at
> >>the -173.1 m mark on ruler A) and when this clock reads t'=2
> >>microseconds, it's lined up with a clock on ruler A that reads t=2
> >>microseconds (the one at the 346.2 m mark on ruler A). However, from B's
> >>point of view this isn't because the clocks on ruler A are ticking
> >>faster, it's just because the clocks on ruler A are out-of-sync--in B's
> >>frame, the clock at the 346.2 m mark on ruler A is consistently 0.5
> >>microseconds ahead of the clock at the -173.1 m mark on ruler A (look at
> >>the top part of the diagram, for example). If you follow each of these
> >>clocks from one moment to the next in B's frame, you see that
> >>individually they do tick at half the rate of B's clocks, not twice the
> >>rate.
> >>
> >>
> >
> >All these imaginary situations is pointless. If an observer wants to
predict
> >the rate of a clock or the length of a rod moving wrt him he uses the LT
or
> >IRT. The LT is incomplete because it assumes that the observer is at
> >absolute rest.
> >
>
> Nope, it doesn't. Again, if the 5 assumptions I outlined earlier hold
> up, then the LT will work for transforming between the measurements of
> any two observers, regardless of their absolute motion.

The 5 assumptions you outlined do not hold up.
>
>
> >>
> >>
> >
> >Sure he uses the LT and his measurements of the supernova to predict what
is
> >the reading in your clock when the supernova will happen.
> >
>
> No, he doesn't need to do any calculations at all, he just looks at a
> photo of the supernova as it happened, and observes that in this photo,
> the physical clock on my physical ruler which was right next to the
> supernova as it happened reads "1905" in the picture.

So now you can take a picture of an imaginary clock??
>
>
> >
> >
> >
> >>But each observer will
> >>have his own series of clocks, and will assign a time-coordinate to the
> >>supernova by looking at the reading on the clock in *their own* system
> >>which was next to the supernova when it happened. Just by taking a
> >>picture of the location of the supernova, and looking at the reading on
> >>each observer's clock which was next to it at the moment it happened, I
> >>can see what time-coordinate each observer assigns to the
> >>supernova--this makes the physical meaning of each observer's
> >>coordinate-system completely transparent, as opposed to the case where
> >>each observer has to perform some mathematical calculations to figure
> >>out the time-coordinate of distant events based on measurements made at
> >>other places and times.
> >>
> >>
> >
> >You can do all that without calculations using the LT or IRT??
> >
>
> Yes, you just look at the actual readings on physical clocks which are
> at rest in a given observer's frame, and which the observer has
> "synchronized" by assuming light moves at the same speed in all
> directions relative to himself (which means that if he is moving
> relative to you, then his clocks will look out-of-sync from your point
> of view...this is the RoS). Again, Einstein *derived* the LT from
> exactly this sort of physical picture, I can provide you with references
> if you like.

Jesse there is no physical clock next to the super nova!!!!
>
>
>
> >
> >
> >>
> >>
> >>
> >>>The LT or IRT can calculate what each observer will see the super
> >>>nova using his own clock.
> >>>
> >>>
> >>>
> >>Yes, but this isn't as physically transparent as just looking at the
> >>reading on the clock in each observer's system which was right next to
> >>the supernova when it happened.
> >>
> >>
> >
> >You can read what each clock says next to the supernova without
> >calculatations?
> >
>
> Sure, just look through your telescope, and at the moment the supernova
> occurs, look at what the clock right next to it said at that moment. No
> calculations are needed at all for this.

So according to you this clock next to the supernova really exist
physically. I don't buy that at all.
>
>
> >>>
> >>>
> >>No, see above. If each observer synchronizes his clocks based on the
> >>assumption that light travels at the same speed in all directions
> >>relative to himself (with speed defined in terms of what you called
> >>'OWLS' above), then different observers will disagree about
> >>simultaneity, and it is this disagreement which allows *every* observer
> >>to measure that rulers moving relative to himself shrink, and clocks
> >>moving relative to himself slow down.
> >>
> >>
> >
> >OWLS has never been measured. It is likely that OWLS is distance
dependent.
> >
>
> I am not sure exactly what you mean by "OWLS", I was just using that
> term because you seemed to be saying earlier that if you measure the
> position and time a light beam was emitted and compare to the position
> and time it was received, then calculate (distance interval)/(time
> interval), this would be an OWLS measurement--was I understanding
> correctly?

Yes.....OWLS=one-way speed of light measured with two spatially separated
and synchronized clocks.
Einstein realized that OWLS is not equal to c so he invented the e-synched
clocks to make OWLS equal to c.
>

> >

> >>>
> >>>
> >>If you believe in ether that may be true "objectively", but it will
> >>nevertheless be true that each observer will *measure* all rulers moving
> >>relative to himself to shrink and all clocks moving relative to himself
> >>to slow down, if they make these measurements in the way that was
> >>specified by Einstein (a network of rulers and clocks at rest relative
> >>to the observer, with the clocks 'synchronized' using the assumption
> >>that light has the same speed in all directions relative to the
> >>observer, even if this assumption is 'objectively' wrong).
> >>
> >>
> >
> >The problem with Einstein's net work of clocks and rulers is that he
assumed
> >that these net works are at a state of absolute rest.
> >
>
> No he didn't. Again, see my 5 assumptions above, as long as they all
> hold then it is absolutely certain that the LT will accurately transform
> between the measurements of *any* two observers regardless of their
> "absolute motion".

Your 5 assumptions do not hold.
>
>
>
> >>

> >I understand the relativity of simultaneity very well and I understand it
is
> >based on the bogus assumption that the observer in the train is moving
wrt
> >light.
> >
>
> Only from the track observer's point of view.

The track observer's point of view has no relevancy what the train observer
will see.

>>From the train observer's
> point of view, the RoS is a consequence of the fact that light moves at
> the same speed in all directions relative to himself, but the observer
> on the track is moving wrt light. Either of these points of view is
> equally valid and will lead to the same conclusions about the RoS. Thus
> the RoS is based on the idea that each observer believes light moving at
> the same speed in all directions *relative to himself*.

Each observer will reach his own conclusion and they both will conclude that
the flashes are simutlaneous but the simultaneity will occur at different
times due to the train and the track are in different states of absolute
motion.
>
>
>
>
> >>No, the LT does not use the notion of "light path length". In the LT,
> >>the "length" of a moving rod is found just by comparing the position of
> >>the back end of the rod and the position of the front end of the rod "at
> >>the same moment", with the notion of "the same moment" defined to mean
> >>that the reading on the clock at the same position as the back end
> >>matches the reading on the clock at the same position as the front end,
> >>with the clocks at rest relative to the observer and "synchronized"
> >>using the assumption that light travels at the same speed in all
> >>directions relative to the observer (so that if a light flash is emitted
> >>at the midpoint of two clocks, the clocks should both read the same time
> >>when the light beam hits each one). Of course, this "synchronization"
> >>procedure guarantees that two clocks which are in-sync in their own rest
> >>frame will be out-of-sync when compared with a set of clocks in motion
> >>relative to them, so different observers will define simultaneity
> >>differently.
> >>
> >>
> >
> >When you are using clocks to measure length you are measuring light path
> >length.
> >
>
> When you measure light-path length, the time when the light is emitted
> at one end of the object is *different* from the time when the light is
> received on the other end, no? If so, this is different from the
> procedure for measuring length I gave above, where you compare the
> position of the back end at a given time with the position of the front
> end at the *same* time (according to local clocks).

You can't measure the light path length of a moving rod that way.
>
>
> >
> >
> >
> >>But this is how you are assumed to measure length according to the LT.
> >>Of course, you can then prove that if each observer does define length
> >>this way, and that if each observer also defines "simultaneity" in the
> >>way I've already discussed, then each observer will get exactly the same
> >>value for distance/time between the emission of a light beam and its
> >>detection. Based on this, you know that each observer is *also* free to
> >>define length as (time for light to travel between two ends of an
> >>object)*(speed of light), but this will only work for an object which is
> >>at rest relative to the observer. It is certainly not true that current
> >>physics would define the length of a *moving* object this way,
> >>
> >>
> >
> >Length of a moving object is determined by the LT or IRT.
> >
>
> You can't define "length" in terms of some abstract mathematical
> transformation, you have to define it in purely physical terms, and then
> *derive* the transformation from those physical assumptions.

Your procedure is non-physical. Furthmore there is no way to measure the
length of a moving rod physically.
>
>
> >
> >>>I assign corrdinates using the LT or IRT.
> >>>
> >>>
> >>>
> >>Again, by "assign coordinates" I'm talking about what physical
> >>measurements you must make to determine the coordinates of a given
event.
> >>
> >>
> >
> >The observer makes measurement with his clock and ruler to determine the
> >coordinates of the event and he uses the LT or IRT to transform these
> >coordinates to another frame.
> >
>
> Again, this would make relativity into an exercise in abstract
> mathematical games, not a physical theory. The whole point of the LT is
> that they *predict* how measurements made by one observer's physical
> ruler-clock system will match up with measurements made by another
> observer's system. None of the observers need to know anything about the
> LT in advance in order to build these physical measuring systems.

So now you are saying that there is no need for the LT. In that case why did
Einstein bother to invent it??
>
>
> >>

> >>No, the RoS is *based* on the isotropy of the speed of light in each
> >>reference frame.
> >>
> >>
> >
> >No RoS is not based on the isotropy of the speed of light. In Einstein's
> >train example he said that the train observer is runhing toward the light
> >front from the front of the train and he is receding away from the light
> >front from the back of the train.
> >
>
> Only from the point of view of the observer on the track!

The track observer doesn't see that at all. He knows that the second
postulate of SR applies in the train and therefore he concludes that the
ends of the train is not moving wrt to the light in the direction of
relative motion between the track and the train.

>You could
> equally well consider things from the point of view of the observer on
> the train--in this frame, it would be the observer on the track who is
> moving towards the light emitted at the back of the train and away from
> the light emitted at the front of the train.

Similarly the train observer knows that the SR postulate forbids that the
track observer to move wrt to the light fronts in the direction of relative
motion between the track and the train.

>Whichever way you look at
> it, you will get exactly the same predictions about how the
> train-observer's clocks readings match up with the track-observer's
> clock readings at the moment a given pair of clocks pass next to each
other.
>
>
> > Clearly this means that the speed of light
> >in the train is not isotropic.
> >
>
> In the frame of the track-observer, light moves at the same speed in all
> directions relative to himself, but not relative to the observer on the
> train. In the frame of the train-observer, light moves at the same speed
> in all directions relative to himself, but not relative to the observer
> on the track. So, the speed of light is isotropic in each observer's
> rest frame.

That's right but then you assumed that the direction of relative motion
between the track and the train as the direction of absolute motion for the
train and reached the conclusion that one of the train observer is moving
wrt the light fronts and the track is not. You use this bogus assumptuon to
arrive at the bogus concept of RoS.
>
>
> >
> >
> >
> >>Suppose the observer on the train has two clocks at
> >>either end of the train, and flashes a light at the exact midpoint of
> >>the train, then "synchronizes" the two clocks so that each clock has the
> >>same reading at the moment the light hits it (in other words, he assumes
> >>light must take the same amount of time to travel from the midpoint of
> >>the train to the clocks on either end, which means he's assuming it
> >>travels at the same speed in both directions in the train's rest frame).
> >>But from the point of view of the observer on the track, the back end of
> >>the train is moving towards the point in space where the flash of light
> >>was emitted, while the front end of the train is moving away from it, so
> >>if the observer on the track assumes that light travels at the same
> >>speed in all directions in *his own* frame, that guarantees that he will
> >>see the two clocks of the train-observer to be out-of-sync if the
> >>train-observer "synchronizes" them in this way.
> >>
> >>
> >
> >The train observer doesn't care what the track observer sees. The train
> >observer will conclude that if he emits a pulse of light in both
directions
> >simultaneously it will hit the ends of the train simultaneously.
> >Likewise the track observer doesn't care what the train observer sees. He
> >will sees both light pulses hit the ends of the train simultaneously.
> >
>
> No, the track observer can't see the light hit both ends simultaneously
> or it would violate the isotropy of light in his own frame.

You are wrong. The track observer will see the light hit both ends
simultaneously because at the time the light pulses were emitted
simultaneously both end of the train were at an equal distance from the
point of emission.

>In his
> frame, the light was emitted from the midpoint of the train, but the
> back of the train is moving towards the point where the light was
> emitted and the front is moving away from that point, so he must see the
> light hit the back end first if light travels at the same speed in both
> directions in his own frame.

Relative motion between the train and the track has no effect on transit
time for light to reach the target. Only absolute motion will affect the
transit time.
>
>
>
> >
> >
> >
> >Yes it does. I suggest that you check with other SRians.
> >
>
> What do you mean by "the transit time of an observed rod"? I assumed you
> meant a rod which is at rest in the observer's own frame. It's certainly
> true that the time for the light to get from one end to another of a rod
> which is *moving* in my frame will be different depending on whether the
> light was emitted at the front end or the back end, but this is just a
> consequence of the fact that I see light going the same speed in both
> directions, regardless of the velocity of the source.

This assumption is wrong. An observer will see a moving rod to have the same
transit time in all directions. That's the reason why the speed of light is
isotropic in the frame of the moving rod.
>
> >
> >
> >
> >>Again, the RoS is derived from the fact that each
> >>observer *assumes* light travels at the same speed in all directions in
> >>his own frame, and uses this assumption to synchronize his own clocks.
> >>If each observer synchronizes his clocks this way, and if there's at
> >>least one frame (the rest frame of the ether, perhaps) where a ruler
> >>moving at velocity v will shrink by squareroot(1 - v^2/c^2) and a
> >>clock's ticks will extend by 1/squareroot(1 - v^2/c^2), then it is
> >>possible to prove mathematically that the Lorentz transformations will
> >>work in *all* frames, and that all observers will measure moving rulers
> >>to shrink and moving clocks to slow down in exactly the same way. I can
> >>show this proof, if you don't believe me.
> >>
> >>
> >
> >What is this got to do with my saying that RoS makes the bogus assertion
> >that the transit time for a moving rod is different in different
directions?
> >
>
> Oh, OK, you are talking about a moving rod. But if a light wave moves at
> the same speed in both directions in my frame (ie the speed of light is
> isotropic in my frame), that means the transit time to get from one end
> to another of a rod which is moving in my frame *must* be different
> depending on which direction the wave is going. Suppose at time t=0 in
> my frame, one end of the rod is at position x=0 and the other is at
> position x=L, and the rod is moving in the +x direction with velocity v.
> In that case, if a light beam is emitted at position x=0 at time t=0,
> and it moves right at velocity c, then it will catch up with the other
> end when ct = L + vt, or when t=L/(c-v). On the other hand, if a light
> beam is emitted at position x=L at time t=0, and it moves left with
> velocity c, then it will catch up with the other end when vt = L - ct,
> or when t=L/(c+v). Since c and v are positive, L/(c+v) < L/(c-v), so
> clearly the assumption that light moves at speed c in both directions in
> my frame *requires* me to believe the transit time for a moving rod is
> different in different directions. If the transit time for a moving rod
> were the same in both directions in my frame, then the speed of light
> could not be isotropic in my frame.

The above reasoning is bogus. Transit time is affected only by the state of
absolute motion of the rod not the relative motion of a rod with that of an
ovserver.
>
>
>

> >>>>
> >>>>
> >>>This is how it works in both SR and IRT.
> >>>
> >>>
> >>>
> >>No, you're misunderstanding SR. If each observer assigns coordinates
> >>using the ruler/clock system I've described, then the train observer
> >>will indeed assign the two flashes different time-coordinates,
> >>
> >>
> >
>

> >This is a bogus assumption. The flashes occurred simultaneously when the
> >train observer was at equal distance from both flashes.
> >
> >
> >
> >>Just plug some numbers into the Lorentz
> >>transformation and you will see that this is true.
> >>
> >>
> >
> >The LT does not confirm the validity of the RoS.
> >
>
> Of course it does,

 No it doesn't.

>because if you plug in two events which have the same
> time-coordinate but different space coordinates in one frame, then you
> will *always* find the same two events have different time-coordinates
> in another frame which is in motion relative to the first. Just try
> plugging in some numbers into the equations and you will see this is true.

Each observer must use his own clock and ruler to determien the simultaneity
of distant events.

Ken Seto

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