According to the theory of evolution to the extent of my knowledge, the universe originated from an infinitely small, infinitely dense and infinitely hot piece of matter.
The Theory of Evolution states no such thing, nor does it event come close to attempting such a topic. Perhaps you are thinking of
The Big Bang Theory or
Abiogenesis, both of which are seperate theories from
The Theory of Evolution. Hopefully we can overcome this hurdle rather quickly in order to answer your other questions (as in: I hope you aren't trying to "bash" evolution because you can't grasp cosmology). As for the reaminder of the post, I will leave that for some of the other posters who are more versed in the laws of physics.
Who are we? We find that we live on an insignificant planet of a humdrum star lost in a galaxy tucked away in some forgotten corner of a universe in which there are far more galaxies than people
-Carl Sagan
For me, it is far better to grasp the Universe as it really is than to persist in delusion, however satisfying and reassuring.
-Carl Sagan
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