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



Dono
Posts:
368
Registered:
11/6/06


Re: Misner, Thorne and Wheeler, Exercise 8.5 (c)
Posted:
Apr 13, 2013 7:12 PM


On Apr 8, 6:08 pm, rotchm <rot...@gmail.com> wrote: > > Yes, thats a "trivial" solution and as you hinted, there are others. > The general solution to this is > r = s(At2 + Bt + C), which can be ~ at + b if its a perfect square. >
You mean r=\sqrt(At^2+Bt+C), arithmetic ignoramus.
r = s(At2 + Bt + C) is nothing but a polynomial degree 2 multiplied by "s", whatever that may be. And, as such, this isn't a solution for the ODE.
You can't even write the solution correctly. I hate to break it to you but even as you copied this solution from a free software package, it isn't the correct solution. You were too lazy in your copying, A, B and C aren't arbitrary, they are tied to each other through some constants of integration, c1=r(0), c2=r'(0) and c3=r"(0), as the final solution needs to depend on the initial conditions. But you are too big of an idiot to know this.


Date

Subject

Author

4/7/13


Guest

4/7/13


Lord Androcles, Zeroth Earl of Medway

4/8/13


Lord Androcles, Zeroth Earl of Medway

4/8/13


Hetware

4/8/13


Lord Androcles, Zeroth Earl of Medway

4/8/13


Hetware

4/9/13


Lord Androcles, Zeroth Earl of Medway

4/9/13


Hetware

4/8/13


Hetware

4/8/13


Lord Androcles, Zeroth Earl of Medway

4/9/13


Hetware

4/9/13


Lord Androcles, Zeroth Earl of Medway

4/9/13


Hetware

4/9/13


Lord Androcles, Zeroth Earl of Medway

4/9/13


Hetware

4/8/13


Dirk Van de moortel

4/8/13


Lord Androcles, Zeroth Earl of Medway

4/8/13


rotchm@gmail.com

4/9/13


Dirk Van de moortel

4/13/13


Dono

4/13/13


rotchm@gmail.com

4/13/13


Dono

4/13/13


Dono

4/13/13


Dono

4/13/13


rotchm@gmail.com

4/13/13


Dono

4/13/13


rotchm@gmail.com

4/13/13


Dono

4/13/13


Dono

4/13/13


rotchm@gmail.com

4/13/13


Dono

4/13/13


rotchm@gmail.com

4/13/13


Dono

4/9/13


Guest

4/9/13


Dirk Van de moortel

4/9/13


Lord Androcles, Zeroth Earl of Medway

4/8/13


Rock Brentwood

4/8/13


Hetware

4/8/13


Lord Androcles, Zeroth Earl of Medway


