The not so Big Bang
Astrophysics with SL again. Started by discussing Newtons static model of the Universe and they quickly got the idea that if the universe is static then it must be infinitely big and time must be infinite, one student then made an interesting observation. " remember what you said about the end fate of the universe being the point at which energy had completely spread out then there would be non temperature gradients so no work could be done? Well if time was infinite then we would have reached that state already:"
Good point.
After that I decided to build the universe in Interactive physics so set about arranging particles for the big bang. The students got a bit bored so I pointed ou that the original had taken 7 days so what's a few minutes when the result will be the most important event in history. The idea ids to group some particles in the middle of the screen, turn off gravity switch on electrostatic force the POW they fly apart. Completely fake of course but the purpose is to show that if you make any of the particles the frame of reference then all the others will move away from it. It worked last time as you can see here.
This time the force was a bit big and all the particles flew apart so quickly you couldn't see anything. Quite realistic really