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Re: bringin einstein and lorentz to justice

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Dirk Van de moortel

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Sep 10, 2008, 6:20:58 AM9/10/08
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dedanoe <ded...@gmail.com> wrote in message
2d2bc633-140c-4bf0...@k13g2000hse.googlegroups.com
> Under the leadership of Einstein's SRT:
>
> t'=(t-V/c x/c)/Sqrt(1-Sqr(V/c))
> t=(t'+V/c x'/c)/Sqrt(1-Sqr(V/c))
>
> x'=(x-Vt)/Sqrt(1-Sqr(V/c))
> x=(x'+Vt')/Sqrt(1-Sqr(V/c))
> ---------------------------------
> As cited from "General Physics I"
> SBN: 9989-43006-3
> =================================
> The hack:
> ---------------------------------
> x'/t = (x-Vt)/(t'+V/c x'/c) and
> x/t' = (x'+Vt')/(t-V/c x/c) ==>
> x't'+VSqr(x'/c) = xt-Vt^2 and
> xt-VSqr(x/c)=x't'+Vt'^2 ==>
>
> x't'-xt=-V(Sqr(x'/c)-t^2) and
> x't'-xt=-V(Sqr(x/c)-t'^2) ==>

Typo.
That should be +t^2 and +t'^2
x't'-xt=-V(Sqr(x'/c)+t^2)
x't'-xt=-V(Sqr(x/c)+t'^2)

>
> -(x't'-xt)/V=(t^2+Sqr(x'/c)) and
> -(x't'-xt)/V=(t'^2+Sqr(x/c)) ==>

This is correct again.

>
> t^2+Sqr(x'/c)=t'^2+Sqr(x/c) ==>

Yes, we normally write this as
(x/c)^ - t^2 = (x'/c)^2 - t'^2
It's called the invariance of the interval.

>
> (t-t')(t+t')=(x-x')/c (x+x')/c

sure.

>
> V=x/t=c and V'=x'/t'=c

Where do you get this from?

When you about the coordinates of a light signal sent
out from the origin, you can say, and derive from the
transformation that
if the signal has equation
x/t = c
in the in the unprimed system, then it has equation
x'/t' = c
in the in the primed system.

Do you understand this?

Dirk Vdm
[ removed silly newsgroups and followup to sci.physics.relativity ]

dedanoe

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Sep 11, 2008, 4:34:44 AM9/11/08
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On Sep 10, 12:20 pm, "Dirk Van de moortel"
<dirkvandemoor...@nospAm.hotmail.com> wrote:
> dedanoe <deda...@gmail.com> wrote in message
>
>   2d2bc633-140c-4bf0-bf4c-f22036660...@k13g2000hse.googlegroups.com
>   [ removed silly newsgroups and followup to sci.physics.relativity ]- Hide quoted text -
>
> - Show quoted text -

(x, t) and (x', t') are the properties of the moving body that we
observe in K and K' coordinate systems thereby they cannot be
considered as property of the light signal at the same instance. the
light signal must have its own (X, T) and (X', T') properties in K and
K' reference frame.

Dirk Van de moortel

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Sep 11, 2008, 1:34:41 PM9/11/08
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dedanoe <ded...@gmail.com> wrote in message
d222601b-abe3-4864...@m36g2000hse.googlegroups.com

You see this much too narrow.
In the context of the Lorentz transformations (provided by you)
(x, t) and (x', t') are the coordinates of arbitrary events as
measured, observed or calculated in two coordinate systems.
Any event taking place at location x at time t, as observed in
system K, takes place at location x' at time t', as observed in
system K', whereby the four numbers x,t,x',t' are related by
the transformation equations.

When you write x/t = c and x'/t' = c, the numbers x,t,x',t'
are still related by the transformation equations, but this time
they are only valid for events taking place on the path of a
particular light signal.

Do you understand that?

Dirk Vdm

glird

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Sep 14, 2008, 9:43:52 PM9/14/08
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On Sep 11, 1:34 pm, "Dirk Van de moortel" wrote:
> dedanoe <deda...@gmail.com> wrote

<<< When you speak about the coordinates of a light signal sent


out from the origin, you can say, and derive from the

transformation that if the signal has the equation
x/t = c
in the in the unprimed system, then it has the equation
x'/t' = c
in the primed system. >>>


>
<< (x, t) and (x', t') are the properties of the moving body that we
observe in K and K' coordinate systems

In the context of the Lorentz transformations (provided by you)
(x, t) and (x', t') are the coordinates of arbitrary events as
measured, observed or calculated in two coordinate systems. >>
>

One of the two is moving at a different velocity than the other,
as plotted by both of them.

< Any event taking place at location x at time t, as observed in
system K, takes place at location x' at time t', as observed in
system K', whereby the four numbers x,t,x',t' are related by
the transformation equations. >
>

in classical physics the relation was given by the Galilean
transformation equations. In relativistic physics it is given
by the Lorentz transformation equations.

< When you write  x/t = c and x'/t' = c, the numbers

[denoted by the symbols] x,t,x',t'


are still related by the transformation equations, but this time
they are only valid for events taking place on the path of a
particular light signal.
Do you understand that?
Dirk Vdm >>
>

That's correct wrt the Lorentz transformations. It is also correct
for an infinity of cases in which the length and time deformations are
NOT those required by the LTE.
It is false wrt the Galilean transformations

glird

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