00:01
In this question, we're going to talk about the cosmological constant problem.
00:08
Now, you might recall that the cosmological constant is a, or perhaps was, a piece of einstein's theory of general relativity.
00:25
And in general relativity, it was added in so that the universe could be in a steady state.
00:33
Basically, dermorovativity predicted that gravity would pull eventually all of the objects in the universe together.
00:43
The universe would be shrinking in on itself.
00:46
So einstein introduced the cosmological constant in order to resist gravity, basically push outward against it, keeping everything in essentially a static state.
01:05
However, what we see now is that the universe is not actually static, but the universe is accelerating and everything, all the galaxies and the universe are accelerating away from each other, which we call expansion.
01:35
So the universe is expanding.
01:45
And that's one attribute of einstein's cosmological constant, is that if it resists gravity, when it's superliction, strong enough to overpower gravity, then eventually it's going to cause the universe to expand rather than contract and at an accelerating rate.
02:05
Now, one explanation for the cosmological constant comes from quantum fields.
02:15
And quantum fields are the idea that all the particles that we know of like photons and even, you know, leptons and quarks, they're all excitations of quantum fields the way that a photon is an excitation.
02:33
A photon is an excitation of an electromagnetic field.
02:48
And the other examples.
02:52
And what we can do is we look at all of the quantum fields that should permeate the whole universe and add them all up...