You mentioned asking this question because you've been deeply obsessing and pondering your own mortality.

Are you perhaps a teenager? (Or an adult that has just received bad news from the doctor?)

At any rate I don't think the nature and mechanisms of the big bang will give you the answers you are seeking, if human mortality is your ultimate question.

I mean... it's not as if many people in history, who stood before the firing squad, suddenly comforted themselves by visualizing how the Universe might be an 11 dimensional string based construct!

Instead, the soothing answer and reassurance to the question of human mortality is almost always in the real of poetry and music, particularly as it relates to: love.