This is gonna be the thread where we talk about stuff

Ooooh look, a mexican hat potential!

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SpoilerThat aside though, I really do like the mexican hat potential as an easily understandable analogue to spontaneous symmetry breaking - it's right up there with the balanced-pencil metaphor, but more mathematically applicable.

uuurrrr

scienceagen...rising...

The mexican hat potential is a mathematical model of the spontaneous symmetry breaking that occurred in the first moments of the universe. The Higgs particle, so recently discovered, plays a vital part in this model.

Imagine a hemispherical bowl.

Drop a marble into the bowl.

Where does the marble settle? The answer is, of course it settled in the bottom of the bowl, at the lowest point of its gravitational potential. This point, for our purposes, we'll consider it zero. So the marble moved down its potential to a stable minimum, and we'd be reasonable to suggest that that would be zero, no?

But...but what if our bowl wasn't a perfect hemisphere? What if it had bumps and dents? What if it had a bump in the center - or to look at it another way, what if there was a circular trench dug around the center point?

What we have then is the mexican hat potential! If we place a marble in the center, the zero point, then what we have is a symmetry. Everything is balanced, as long as nothing is disturbed, and the system is at a zero point.

But it's not going to be much longer. Quantum fluctuations are growing, disturbing the marble every which way, until -

It rolls off the center point and settles in a stable, non-zero end state. This is known as spontaneous symmetry breaking. For another example, imagine a pencil balanced on its point. As long as it's balanced, it's perfectly symmetrical - if you were looking at it from above, you couldn't say it was pointing anywhere (aside from down. But this is a metaphor). But it can't keep this state of affairs up, and falls over. Now, if you look at it, it's clearly pointing in a direction, and is no longer symmetrical. Not only that, the direction it points in is completely random, but once it has fallen there's no moving it again.

Now, if you link up the Higgs to the picture - the Higgs Boson generates or carries a field known as the Higgs Field, which pervades through space and gives matter its mass. If you imagine the Higgs Field being the mexican hat potential, and the boson being the marble -

IN THE BEGINNING, THE HIGGS WAS BALANCED ON ZERO POINT, AND NOTHING HAD MASS.

AND LO, LIKE THINGS THAT DON'T HAVE MASS, THEY PROCEEDED TO MOVE REALLY FAST!

LIKE, REALLY FAST. SPEED OF LIGHT FAST. AND THEY CREATED THE UNIVERSE BEHIND THEM! (Certainly it can't be said that it's possible to observe anything ahead of them, because you know, speed of light)

BUT THEN THE HIGGS DROPPED INTO A STABLE NON-ZERO STATE AND THEN EVERYTHING HAD MASS D:

AND SO IT WAS THAT INFLATION ENDED.

AND THE UNIVERSE BEGAN TO SLOW ITS EXPANSION.

IT'S STILL SLOWING DOWN TODAY!

But then one of the spacefaring races used their shrink ray on space to make it smaller so that the planets could talk.