Download 2.5.8 the future of the universe

 To
escape the effects of gravity on this
planet you have to reach a minimum of 11.2
km s-1
 Less than that, you will fall back to the
surface.
 More than that, the spare kinetic energy will
propel you out of the gravitational well and
you will continue into space.
 Bearing
this in mind, if we calculate the
mean density of the universe, we can work
out what will happen to the Universe we live
in.
 If we assume the Universe is homogenous,
and we divide the total mass of all of the
galaxies by the current volume of the
Universe, we get a value of 10-27 kg m-3 .
 Consider
then, instead of something trying to
escape the confines of the Earths
gravitational well, but the gravitational well
of a galaxy and all surrounding galaxies.
 In order to do so, the Ep of a galaxy would
have to equal the Ek of the same galaxy.
 Substituting H0 in (v = H0r) into the
equations, we get a value ρc = 9.5 x 10-27 kg m-3 .
 At
present, calculations of density are of the
same order of magnitude as the critical
density.
 It is, however, too close to call as to the
outcome of the Universe.