Howard, Sheldon and others in “The Einstein Approximation”

Sheldon, what the hell are you doing?

Same thing I've been doing for three days. Trying to figure out why electrons behave as if they have no mass when traveling through a graphene sheet.

With marbles?

I needed something bigger than peas now, didn't I?

Sheldon, when was the last time you got any sleep?

I don't know, two, three days? Not important. I don't need sleep. I need answers. I need to determine where, in this swamp of unbalanced formulas squateth the toad of truth.

[aside to Leonard] The toad of truth? Is that a physics thing?

No, that's a crazy thing.

[making her way to Sheldon] Okay, Sheldon, what happens to our neuro-receptors when we don't get enough REM sleep?

[looks at Bernadette] They lose their sensitivity to seratonin and norepinephrine.

Which leads to…?

Impaired cognitive function.

Right. [firmly, pointing at his bedroom] So march in there, brush your teeth and go to bed!

[in a childish manner] …But I don't wanna go to bed.

[firmly] I'm gonna count to three. One…

[exasperated] Oh, all right! [leaves]

[shocked] That was amazing how you handled him.

I know how to deal with stubborn children. My mother used to run an illegal daycare center in our basement.