From: Daryl McCullough on
Thomas Smid says...

>> >There is nothing in our previous equations
>> >that would have prevented me from making this assumption
>>
>> On the contrary, it leads to a contradiction.
>
>Which would be what? Setting B=0 and A=1 (or vice versa) is fully
>consistent with the assumptions x=ct and x'=ct' (which are the only
>relevant equations regarding the propagation of light).

But there are other criteria to consider. If someone is travelling
at speed v relative to the (x,t) coordinate system, then he is at
*rest* relative to the (x',t') coordinate system. This implies that

for any event e such that x(e) = v t(e),
x'(e) = 0.

Going back to

x' = A x + B t

this implies that

B = - vA

Choosing B=0 is inconsistent.

>> >which, as mentioned above merely implies that t and t'
>> >are independent variables.
>>
>> They aren't independent variables. Given x and t, t' is
>> determined.
>>
>> > (1) x1'(x1,t) + c t'(x1,t) = (A+B) (x1 + ct)
>> > (2) x2'(x2,t) - c t'(x2,t) = (A-B) (x2 - ct)
>> >
>> >and additionally we have
>> >
>> >(3) x1'(x1,t) - c t'(x1,t) = 0
>> >(4) x2'(x2,t) + c t'(x2,t) = 0
>> >(5) x1=ct
>> >(6) x2=-ct
>> >
>> >Now by virtue of (3)-(6), (1) and (2) become
>> >
>> >(7) 2ct'(x1,t)=(A+B)2x1
>> >(8) 2ct'(-x1,t)=(A-B)2x1
>> >
>> >The question is how ct'(-x1,t) relates to ct'(x1,t). For this we
>> >consider the original transformation for ct'
>> >
>> >(9) ct'(x1,t) = Bx1+Act
>> >
>> >which by virtue of Eq.(5) becomes
>> >
>> >(10) ct'(x1,t) = (B+A)x1
>> >
>> >which obviously means that
>> >
>> >(11) ct'(-x1,t) = -(B+A)x1 =-ct'(x1,t)
>>
>> Thomas, you forget that x1 in equation 10 is *not*
>> an independent variable, it is a *function* of t.
>> In particular, x1 = ct, so (10) should be written
>> as follows:
>>
>> (10) ct'(ct,t) = (B+A)ct
>>
>> Now, if you replace t by -t, you get the correct
>> version of (11)
>>
>> (11) ct'(-ct,-t) = -(B+A)ct = -ct'(ct,t)
>>
>> [Rest deleted, since it relies on a false step]
>
>I am sorry, but I don't think you are right. We can't change the sign
>of the explicit t-dependence here (after all negative times are not
>defined).

You were the one who replaced x1 by -x1. Since x1 = ct, that
is impossible, unless you are replacing t by -t. So don't blame
me.

[Aside: But actually, saying negative times are not defined is
incorrect. The parameter t measures the time since some particular
reference point. For example, in years, 2005 means 2005 years *after*
the birth of Jesus. The year -600 means 600 years *before*
the birth of Jesus. Negative times are just as meaningful
as positive times.]

Anyway, what you have are these:

x'(x,t) + ct'(x,t) = (A+B) (x+ct)
x'(x,t) - ct'(x,t) = (A-B) (x-ct)


If you specialize the first equation to the case x=ct,
and the second equation to the case x=-ct, then these
become:

2ct'(ct,t) = (A+B) 2ct
- 2ct'(-ct,t) = -(A-B) 2ct

or

t'(ct,t) = (A+B) t
t'(-ct,t) = (A-B) t

--
Daryl McCullough
Ithaca, NY

From: Bilge on
Mike:

I'm going to skip your attempt to avoid the fallacies of your
argument. Do you or do you not think the coordinate transformations
for spatial rotations is valid? Is that a yes, no, or does the
answer require a lot fallacious conditions to fit some ideology
you like?

>Bilge wrote:
>> Mike:
>> >If you were just a bit more careful reading my post, I do not claim any
>> >of this stuff. Dr. ALL did claim it.
>>
>> What you did was try to set up a strawman.
>
>I would have done that if I assumed: Bilge <---> Strawman
>
>But since I did not, you claiming I tried to set up a strawman is a
>strawman.
>
>Are you an idiot by the way?

Not unless your thought processes are contagious.


From: Bilge on
Perspicacious:
>Igor wrote:
>> Congratulations! You've just discovered that the average speed of two
>> light rays moving in opposite directions vanishes. What this has to do
>> with inconsistencies in the Lorentz transformation, which you didn't
>> even get to, I have no idea. My first reaction was that this had to be
>> a big joke, since no one could be that stupid. But I could be wrong.
>
>The greatest riddle, with as yet an undiscovered rationale, is why so
>many kooks are drawn to special relativity.

Since you're a kook and you believe you are the world's foremost
authority on the subject, you should have a lot of insight into
the answer.

>I believe the answer is
>that it special relativity is taught primarily by physicists who
>strive for sensationalism and not by mathematicians who prefer
>clarity and logical consistency.
>
>http://www.everythingimportant.org/relativity/special.pdf
>
From: Thomas Smid on
Daryl McCullough wrote:
> Thomas Smid says...
>
> >> >There is nothing in our previous equations
> >> >that would have prevented me from making this assumption
> >>
> >> On the contrary, it leads to a contradiction.
> >
> >Which would be what? Setting B=0 and A=1 (or vice versa) is fully
> >consistent with the assumptions x=ct and x'=ct' (which are the only
> >relevant equations regarding the propagation of light).
>
> But there are other criteria to consider. If someone is travelling
> at speed v relative to the (x,t) coordinate system, then he is at
> *rest* relative to the (x',t') coordinate system.

Only if the two coordinate systems are also travelling with speed v
relatively to each other.

>This implies that
>
> for any event e such that x(e) = v t(e),
> x'(e) = 0.
>
> Going back to
>
> x' = A x + B t
>
> this implies that
>
> B = - vA

It should be x'=Ax+Bct i.e. B=-vA/c actually.

>
> Choosing B=0 is inconsistent.

Not surprisingly because your new conditions
x=vt
x'=0
are inconsistent with the old ones
x=ct
x'=ct'
It is with the latter conditions only that B=0 (or A=0) is consistent.

>
> >> >which, as mentioned above merely implies that t and t'
> >> >are independent variables.
> >>
> >> They aren't independent variables. Given x and t, t' is
> >> determined.
> >>
> >> > (1) x1'(x1,t) + c t'(x1,t) = (A+B) (x1 + ct)
> >> > (2) x2'(x2,t) - c t'(x2,t) = (A-B) (x2 - ct)
> >> >
> >> >and additionally we have
> >> >
> >> >(3) x1'(x1,t) - c t'(x1,t) = 0
> >> >(4) x2'(x2,t) + c t'(x2,t) = 0
> >> >(5) x1=ct
> >> >(6) x2=-ct
> >> >
> >> >Now by virtue of (3)-(6), (1) and (2) become
> >> >
> >> >(7) 2ct'(x1,t)=(A+B)2x1
> >> >(8) 2ct'(-x1,t)=(A-B)2x1
> >> >
> >> >The question is how ct'(-x1,t) relates to ct'(x1,t). For this we
> >> >consider the original transformation for ct'
> >> >
> >> >(9) ct'(x1,t) = Bx1+Act
> >> >
> >> >which by virtue of Eq.(5) becomes
> >> >
> >> >(10) ct'(x1,t) = (B+A)x1
> >> >
> >> >which obviously means that
> >> >
> >> >(11) ct'(-x1,t) = -(B+A)x1 =-ct'(x1,t)
> >>
> >> Thomas, you forget that x1 in equation 10 is *not*
> >> an independent variable, it is a *function* of t.
> >> In particular, x1 = ct, so (10) should be written
> >> as follows:
> >>
> >> (10) ct'(ct,t) = (B+A)ct
> >>
> >> Now, if you replace t by -t, you get the correct
> >> version of (11)
> >>
> >> (11) ct'(-ct,-t) = -(B+A)ct = -ct'(ct,t)
> >>
> >> [Rest deleted, since it relies on a false step]
> >
> >I am sorry, but I don't think you are right. We can't change the sign
> >of the explicit t-dependence here (after all negative times are not
> >defined).
>
> You were the one who replaced x1 by -x1. Since x1 = ct, that
> is impossible, unless you are replacing t by -t.

I replaced x2 by -x1. We have x1=ct and x2=-ct. x1 is always positive,
x2 is always negative, hence t must in both cases always be positive.

Thomas

From: Daryl McCullough on
Thomas Smid says...
>
>Daryl McCullough wrote:

>> Choosing B=0 is inconsistent.
>
>Not surprisingly because your new conditions
>x=vt
>x'=0
>are inconsistent with the old ones
>x=ct
>x'=ct'
>It is with the latter conditions only that B=0 (or A=0) is consistent.

I thought I explained to you already. These equations are for
*different* events. The assumptions are these:

1. For all events e, if x(e) = 0, then x'(e) = -v t'(e).
(The spatial origin of the (x,t) system is moving at velocity -v
as measured in the (x',t') system.)
2. For all events e, if x'(e) = 0, then x(e) = v t(e).
(The spatial origin of the (x',t') system is moving at velocity +v
as measured in the (x,t) system.)
3. For all events e, if x(e) = c t(e), then x'(e) = c t'(e).
(Anything that travels at the speed of light in one system also
travels at the speed of light in the other system.)
4. For all events e, if x(e) = - c t(e), then x'(e) = - c t'(e).
(Same as 3, but for the opposite direction.)

To complete the transformation, we actually need one more fact, which
is a symmetry condition between the two systems:

5. For all pairs of events e1 and e2 such that
x(e1) = 0 and
x'(e2) = 0 and
t(e1) = t'(e2),
then t'(e1) = t(e2).


>> You were the one who replaced x1 by -x1. Since x1 = ct, that
>> is impossible, unless you are replacing t by -t.
>
>I replaced x2 by -x1. We have x1=ct and x2=-ct. x1 is always positive,
>x2 is always negative, hence t must in both cases always be positive.

Either way, you made an error.

The equations we had originally were

x'(x,t) + c t'(x,t) = (A+B)(x + c t)
x'(x,t) - c t'(x,t) = (A-B)(x - c t)

In the special case in which x=ct, the first equation becomes

x'(ct,t) + c t'(ct,t) = (A+B) 2ct

Using x' = c t', this simplifies to

(10) t'(ct,t) = (A+B) t

In the special case in which x=-ct, the second equation becomes

x'(-ct,t) - c t'(-ct,t) = -(A-B) 2ct

Using x' = -c t', this simplifies to

(11) t'(-ct,t) = (A-B) t

These two equations don't imply B=0.

--
Daryl McCullough
Ithaca, NY