Sean Carroll

But the laws of physics, as we currently understand them, might not be right.

So I wouldn't even call that impossible.

I would say it violates the laws of physics.

Cold fusion, as far as we know, doesn't even necessarily violate the laws of physics.

When it first came out, that was like when I first arrived at graduate school, roughly speaking.

So I was at Harvard, and there were people in the physics department, applied physics, astronomy, who were thinking very hard about, you know, could this work?

Could we understand this?

Could we do the math?

understand quantum tunneling and nuclei and things like that.

And they basically all came around and said, no, it doesn't seem to actually work.

But that's different than impossible, right?

Like, you know, you might, I don't think there's a theorem that says that something like cold fusion cannot possibly work.

I think what there is is the real world scientific progress that says, you know, we've done the experiments.

We've seen experimentally that a lot of these claims are not true.

We've done the theory.

We see that the particular setup that people have been looking at can't really work this way according to the laws of physics as we understand them.

And we move on.

But we don't claim that things are impossible in science.

Things are just not as clear-cut as that.

We learn by going back and forth between theory and experiment and so forth.