Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Cosmology Problem, Friedman equation

  1. Dec 29, 2005 #1
    I am asked in a question to show that the friedman with k<0 equation can be solved by substituing

    a= b(1-cos(theta)) and t = c(theta- sin(theta).

    a is scale factor,
    t is time
    b,c are constants

    Can anyone outline the general procedure to go about solving this.

    I've tried substituting da/dt using the chain rule to obtain da/d(theta)*d(theta)/dt, but this leads to an uneliminated cos terms...
    Last edited: Dec 29, 2005
  2. jcsd
  3. Dec 31, 2005 #2
    Can you please write the friedman equation. Need to know your notations.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook