What is some evidence for the Big Bang? Why do some people not agree?
The expansion of the universe redshifts the light coming from galaxies. The remnant of the heat liberated in the primordial explosion is the cosmic back ground microwave radiation
They have some reason for red shift.other than expansion. The big bang is not all. The problem is that the universe is too young to have had time to thermalise, i.e. to equilibrate its temperature over such a large scale. To remedy this problem, a period of hyper-expansion, called inflation, had to be postulated, which precedes the Big Band itself.