Question:
Would you please explain what amplitude is in quantum
physics.

Replies:
Aaron,

In quantum physics, particles are not described as being in one place at one
time. We use items known as wave functions to describe particles. Research
shows that knowing where a particle is at one moment does not mean we can
know where it is one second later. Also, measuring where something is will
usually make it move. To talk about a real particle, we can only say where
it is likely to be. We can only say how it is likely to be moving. Most of
quantum physics is based on probability.

The "wave function" of a particle provides a way to combine all these
probabilities into one function. The mathematics is easier to deal with if
we can use trigonometric functions. The amplitude is the value of the wave
function at a certain position and time. The square of that amplitude
corresponds to how likely the particle is to exist at that position and that
time. Where the amplitude is largest is where the particle is most likely
to be at a certain time.

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.