Re: Androcles, one more try

From: Androcles (dummy_at_dummy.net)
Date: 12/29/04 

Date: Wed, 29 Dec 2004 20:11:28 GMT

"Randy Poe" <poespam-trap@yahoo.com> wrote in message
news:1104338617.032514.210040@z14g2000cwz.googlegroups.com...
>
> Randy Poe wrote:
>> I've decided to see what happens if I make one more good
>> faith effort to work through a derivation of SR. This time
>> I'm not going to get into an argument about what Einstein
>> said. This will be my own derivation. It will be based
>> very closely on my reading of "Electrodynamics" but I
>> will define my own terms. The Einstein paper will not be
>> required to follow the derivation.
>>
>> So Androcles, if you want to get into an argument about what
>> the author means by a symbol, you will be arguing with ME
>> about what *I* mean by a symbol *I DEFINED*. I'm curious
>> to see whether that's the route you'll go.
>
> Androcles has been expressing increasing impatience about
> getting to the actual derivations. I note that the one post
> he has not responded to is the one in which I move forward
> into the actual derivation. I'll be charitable and assume he
> just missed it. So Androcles, wherever you are, if you are
> actually interested in moving forward, will you read this?
>
> ====================================================
>
> OK, let's move forward. Let me generalize the very key
> statement I made above, because that's where I'm moving
> forward from.
>
> "I, in the S frame, can observe x at a given time t,
> can calculate x-vt, and I will get a constant value
> no matter what time I take that observation and do that
> calculation."

Fucking whoop-de-do. How absolutely amazing.
Your brilliance astounds me.
>
> Since it distressed you to talk about a general x which
> can be applied to different things, I'll now assign everything
> a specific name.
>
> x_orig will be the x position of the origin of M (the
> paint spot on the truck). You agree this paint spot
> moves, and so x_orig changes in time.

Yeah, yeah...(fixed font req.)
________________
[Poe's Trucking Inc.] [ \_
[___________________] [__^|
 oo oo o
^x-orig goes here.

> x_orig' will be the value x_orig - vt. You agree that
> I can measure x_orig at any time, subtract the corresponding
> value of vt, and get a constant. That is, even though
> x_orig changes with time, x_orig' does not.

          ________________
            [Poe's Trucking Inc.] [ \_
            [___________________] [__^|
 oo oo o
^x-orig' goes here.

x_orig-vt is a constant in S. Got it.

                _____________________ _
                [Poe's Trucking Inc.] [ \_
                [___________________] [__^|
                 oo oo o
<-------vt------>
^ x_orig' goes here.

>
> In fact, x_orig' = 0, because I arranged things that
> way.

Ok.

> I defined t=0 to be the time at which the truck's
> paint spot was at distance 0.

Ok.

>
> You agree that I'm still measuring and calculating in
> the S frame, right?

Yeah, let's keep it that way.

> x_orig is a distance I measure in S from
> the paint spot on the road to the paint spot on the truck,
> and t is the time in the S frame (a variable) at which I make the
> measurement.

Yeah. Do go on.

> Now I'll track another spot on the truck. It's going to be
> in the cargo area of the truck, where a scientist is going
> to be conducting light-reflection experiments. The position
> of the light reflector AS MEASURED IN THE S FRAME will be
> called x1.

                _____________________ _
                [Poe's Trucking Inc.] [ \_
                [___________________] [__^|
                 oo oo o
<-------vt------>
                ^x goes here ^ x1 goes here.

You agree that x1 is changing in time, right,
> since x1 is attached to the truck and the truck is moving
> away down the road?

Yeah.

>
> And I'll define x1' = x1 - vt. Do you agree that x1' is a
> constant, since we showed that x-vt is a constant for
> anything moving with the truck at velocity v?

Yeah.

>
> I'm almost afraid to take one more baby step, but what
> the heck, here it is:
>
> Now the truck paint spot is moving in x alone, so it's
> y and z coordinates, y_orig and z_orig are constants in
> time.

Yeah.

> Do you see that I can give you four parameters
> (x_orig', y_orig, z_orig, t) and
>
> - The first three are constants (I gave you x_orig', not
> x_orig)

Yeah.

> - You can easily calculate x_orig from x_orig' and t

Yeah.

> - So these three constants plus one variable (t) tell you
> everything you need to know (position and time) about the
> paint spot at any time in the future?

Yeah.

> This is a very key point.

Editorial comment ignored.

>
> The very next post will define tau, I promise, so long
> as we agree on these simple but very important things.

This is like pulling fucking teeth.

Androcles.