**Quantum mechanics**, also known as

**quantum physics**or

**quantum theory**, is a branch of physics

providing a mathematical description of much of the dual particle-like and wave-like behavior and interactions of energy

and matter

. It departs from classical mechanics

primarily at the atomic and subatomic scales, the so-called quantum realm

. In advanced topics of quantum mechanics, some of these behaviors are macroscopic and only emerge at very low or very high energies or temperature

s.

If the price of avoiding non-locality is to make an intuitive explanation impossible, one has to ask whether the cost is too great.

For those who are not shocked when they first come across quantum theory cannot possibly have understood it.

...the "paradox" is only a conflict between reality and your feeling of what reality "ought to be."

I think I can safely say that nobody understands quantum mechanics.

Quantum theory was split up into dialects. Different people describe the same experiences in remarkably different languages. This is confusing even to physicists.