A Very Brief History of the Universe:Notes:
(abbreviated G) is the international term for 1,000,000,000 or 109
. In the U.S. this is called a billion
– almost everywhere else it is a milliard. We use G to avoid confusion. M is for million. The universe
is about 13G years old.
eV are electron
-volts; and electron
has a mass-energy (E=mc2
, remember) of 0.511 MeV.
rad = radiation
, CBR= cosmic background radiation
=quasars, BH=Black hole
, Msun= mass of our Sun.
A.U. is astronomical units
(Sun-Earth distance, = 8 light-minutes); pc is parsecs
: 2.36 light-years.