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How did it all begin?

The universe I mean.

Well, it's complicated.

You know, this is actually a strangely controversial topic to disguise.

It's a deep existential question that philosophers and religions have given answers to.

This is a separate discipline than those two, but it does offer some mathematical answers.

Wrap up in the dominant theory that's been around for decades.

The Big Bang.

So one way of thinking about the Big Bang is it's the moment from which all other time

and therefore space time follows.

Those of us who work in the field of cosmology, which I do, sometimes use the phrase Big Bang

to refer to the time period after space time begins when everything's very hot and

very compressed.

That's Dr. Chanda Prescott Weinstein, a theoretical physicist at the University of New Hampshire.

As a physicist, it's her job to ask these deep questions about how we and the rest of

the universe got to this moment.

How the universe began and how it evolved.

The whole chain of events started really, really fast with what physicists call the

hot Big Bang.

Then immediately afterwards, there is a phase that's less than a second long called the

inflationary period, where space time expands exponentially and becomes rapidly large.

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