Question

What is big bang theory?

Answer 1

hii dear friend!!

If we trace the Hubble expansion back in time, we conclude

1). All matters in the universe should be in a very small volume long time ago:

if we trace back to t =0, the size of the universe is zero!

2). At t =0, all matters must be compressed into zero size.

The universe close to Big Bang (For time 0<t<0.0001 second)

Universe is filled with high energy photons.Temperature is high, about 1012KDensity is high about 1013g/cc.Few massive particles that interact continuously with photons.High energy photons create particle and antiparticles pairs.
i think it may help u dear!!!!!

Answer 2

The Big Bang is a scientific theory about how the universe started, and then made the groups of stars called galaxies. The universe began as very hot, small, and dense with no stars, atoms, form or structure.