In an introductory physics course, there are three big ideas. There is the work-energy principle, the momentum principle and then the angular momentum principle. I'll skip the work-energy principle ...

When a magnetic material like nickel is zapped with an incredibly short laser pulse, it loses its magnetism almost instantly within femtoseconds, or a millionth of a billionth of a second. But physics ...

When a magnetic material is bombarded with short pulses of laser light, it loses its magnetism within femtoseconds (10 –15 seconds). The spin, or angular momentum, of the electrons in the material ...

It depends on what you mean by rotate. A planet in a locked orbit to its star doesn’t rotate with reference to its star; it rotates once (in essence its day) in the same period as its year (orbital ...

Topological insulators do not allow conduction in the bulk, yet they support edge modes that travel along the boundary only in one direction, determined by the carried electron spin, with inherent ...