1st April 2011 Big Bang Theory

 Yesterday's Starts with a Bang is about the Big Bang Theory. It ties together the stuff I've been reading about the alpha beta gamma paper, red shift and blue shift and some theories about the universe.  These are some possible explanations for the observed red shift.

• light gets tired, and simply loses energy over time,
• the Universe oscillates, contracting and expanding over time, and we are simply close to an expanding portion of it,
• physical constants, such as the speed of light, or the gravitational constant, have changed over time,
• the Universe grows steadily and evenly, and creates new matter as it expands, 
• the Universe is rotating rapidly, and that the galaxies that are moving away from us more quickly also have large -- unobservable -- translational motions
• the Universe was expanding, and that the expansion rate was faster in the past! As the Universe moves forwards in time, it cools, expands, and slows down.

The latter leads to the following prediction:

• In the beginning it was so hot the neutrons, protons and electrons couldn't stick together.
• It cooled some and the protons and neutrons got together to form deuterium, helium-3 and helium-4. 

When the cosmic microwave background was discovered, it could be explained as the left-over glow from the Big Bang, supporting this idea.