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

Big bang scenario

  1. May 18, 2004 #1
    BIG BANG SCENARIO WITH ATOMS AND MOLECULES - NOT INDIVIDUAL QUARKS - AT BEGINNING

    Equation for an ideal gas:

    PV = nRT

    T = 10^10 after one second – according to steven Weinberg. I shall assume that T was close to this value when t = 0. R = 8, n, the number of moles of hydrogen in universe = 10^55

    initial radius of universe = 10 ^ 24 metres minimum because (1 – 2GM/ r c ^ 2) ^1/2

    cannot be negative or else imaginary square root results.

    volume of universe = 10 ^ 72 m ^ 3

    therefore pressure at time of big bang = 10^ - 7 N m^ - 2

    there were about 10 ^ - 27 kg m ^ - 2 at the time of big bang.

    Acceleration = force / mass

    so acceleration of 1 m^2 of mass of 10^ -27 kg was 10 ^ -7 / 10 ^ - 27

    this is 10 ^ 20 metres per second per second.

    This means universe was moving close to speed of light after 10 ^ - 12 seconds.

    It took 10 ^ 18 seconds to reach current size – this is 10 billion years.

    Initially atoms were half a metre apart so we would expect to see evidence of
    this in the cosmos at wavelengths of 1000 metres( REDSHIFT)

    If we take initial radius of universe, 10^24 metres, and current radius 10^26 metres
    we should find that:

    [ ( final radius ) ^ 4 divided by ( initial radius ) ^ 4 ] x current cmbr temperature =
    initial temperature of universe.

    ( 10 ^ 26 ) ^ 4 / ( 10 ^ 24) ^ 4 x 2.7 = 10 ^ 8 which is close to Weinberg’s
    temperature of 10 ^ 10 K and could be closer if I had used more accurate numbers.
     
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you help with the solution or looking for help too?
Draft saved Draft deleted



Similar Discussions: Big bang scenario
  1. Before the 'BIG BANG' (Replies: 1)

  2. Big Bang (Replies: 10)

Loading...