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Topic: Misner, Thorne and Wheeler, Exercise 8.5 (c)
Replies: 38   Last Post: Apr 13, 2013 11:57 PM

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 Lord Androcles, Zeroth Earl of Medway Posts: 19 Registered: 4/13/13
Re: Misner, Thorne and Wheeler, Exercise 8.5 (c)
Posted: Apr 9, 2013 3:05 AM

"Dirk Van de moortel" wrote in message
news:kk0e6p\$7g2\$1@speranza.aioe.org...

"Hetware" <hattons@speakyeasy.net> schreef in bericht
news:Duidna9WrZBIBv7MnZ2dnUVZ_rydnZ2d@megapath.net...
> On 4/8/2013 9:27 AM, Dirk Van de moortel wrote:
>> Hetware <hattons@speakyeasy.net> wrote:
>>> This is the geodesic equation under discussion:
>>>
>>> d^2(r)/dt^2 = r(dp/dt)^2
>>>
>>> d^2(p)/dt^2 = -(2/r)(dp/dt)(dr/dt).
>>>
>>> r is radius in polar coordinates, p is the angle, and t is a path
>>> parameter.
>>> The authors ask me to "[S]olve the geodesic equation for r(t) and
>>> p(t), and show that the solution is a uniformly parametrized straight
>>> line(x===r cos(p) = at+p for some a and b; y===r sin(p) = jt+k for
>>> some j and k).

>>
>> Normally we'd write dotted variables, but with quotes it's easier.
>> So write

>
> Like this?
>
> <math xmlns='http://www.w3.org/1998/Math/MathML'

[snip]

This is a text group :-)

Dirk Vdm
==============================================
I knew you would snip, you are such a predictable imbecile.

-- "Dork Van de faggot" <dirkvandemoortel@hotspam.not> wrote in message
news:ke1gcs\$f2d\$1@speranza.aioe.org...
> Indeed, writing LT and inverse:
> x' = g ( x - v t ) [1]
> t' = g ( t - v x ) [2]
> x = g ( x' + v t' ) [3]
> t = g ( t' + v x' ) [4]

[ but v' = x'/t', the inverse velocity ]
> No, imbecile, v' = 0.

"Dork Van de faggot" wrote in message news:kfp3ba\$ku0\$1@speranza.aioe.org...
How hard is it to listen to the definitions and stick with the rules?
"Did you ever had algebra?" - Dork Van de faggot
"the transformation equations are valid only for speeds below or up to c" --
Dork Van de faggot

-- So if T = 5 years and v = 0.8c, then the stay at home twin will
have aged 10 years (2T) while his travelling twin sister will have
aged 6 years (2T/g). <no silly grin>
-- Psychodork Van de improper faggot.