Cosmology and the
Origin of Life
Remember the basic problem:
After t = 15 minutes:
- Temperature = one million degrees
- Fusion stops
- Universe consists of:
- Still a long way to go to reach
The Periodic Table
- Note; nuclei with 5 or 6 nucleons are very unstable and can't
exist very long
- The Universe is completely ionized at this point; no electrons
are bound to atoms
- Universe is an expanding sea of mostly photons in which are mixed
small amounts of atomic nuclei and free electrons
So How do we make GALAXIES ????
The First Problem:
- Matter and Radiation are coupled
- Coupling mechanism is photon scattering
off of free electrons
- Scattering is the random change of direction of a photon. Watch
the Blue photon
- The problem in the early universe now is that there is no place
for the photons to go - they can't escape the matter.
- Radiation and matter temperature are the same due to momentum transfer
between the photons and matter --> Therefore the matter is also at
a temperature of one million degrees.
- This momentum transfer between the radiation and the matter will
not allow the matter to clump together
To build a galaxy we need to grow a
density fluctuation ! --> How is this going to happen?
The tight coupling between the radiation and matter means that the
matter should be distributed like the radiation and we know, from
observations of the MWB, that the distribution of radiation is very
So How come there are galaxies?
The Electronic Universe Project