James Fodor

speaker

3,084 appearances 4 recordings 1 series first heard Jun 2026 last heard 30 Aug

James Fodor’s voice in public audio — every appearance, attributed to the second.

Trend

recordings per month · last 12 months

Recordings per month over the last 12 months — 4 in all, peaking in Aug 2026 with 2.

Appearances

newest first · ▶ plays the moment

The Science of Everything Podcast · Episode 164: Gauge Theory and the Higgs Boson · 30 Aug 2026 podcast

How is it that we get this non-zero vacuum expectation value?

Like, where does it come from?

Another way to ask this question is we're gonna add in an energy term into our Lagrangian, right?

It's gonna be a new potential, which corresponds to this Higgs field.

So we're gonna have to add this in.

What does the form of that potential have to look like in order to get a non-zero vacuum expectation value?

Because it's gonna have to be something different to normal fields.

Most of the potentials and and interactions that we put into our Lagrangian have a quadratic structure, which means it's two fields multiplied together.

So you kind of have a squared term, and so the potential looks like a quadratic.

It's like a parabola, like uh it goes down and then it goes up again.

It turns out that, however, we can get this non-zero vacuum expectation value by introducing a potential with a different structure.

Instead of this quadratic term, which is typical, it has a quartic function.

So that's to the power of four.

And if you uh sketch a quartic function, uh what it looks like, at least the sort of positive version, is that it looks a bit like a W, except the middle part is is smaller.

So like you have a it goes it starts high, goes down, has a trough.

Goes up again and there's a little hill in the middle, down again, and then up again at the end.

So like a W but with a small bit in the middle.

That's what the potential looks like.

And that is very important because just to explain what this potential means, the vertical axis corresponds to the potential energy of the field, the horizontal axis corresponds to the value of the field.

So normally, let's think about what happens when we have our quadratic case.

Showing 541–560 of 3,084 · page 28 of 155