Physics 410/510 First Homework Assignment

Due: Jan 24 at the end of Class

1. Find some Cosmological N-body simulations on the World Wide Web and look at them. Here is a good place to start . Describe their components and the overall behavior of the simulation in terms of predictions that you would make about the observable Universe. What are some of the limitations of these simulations?

2. Integrate equation 20 to produce equation 23.

3. Using the expression for critical density determine the critical density in grams per cubic centimeter when H is in units of 100 km/s Mpc-1

4. We will later make use of a quantity known as the dynamical timescale . Give a physical argument that shows why this timescale goes as:

(G*rho)-1/2

where rho = density.

5. Verify that rho goes as R(t)-3 is the solution to equation 30.