Question about quantum mechanics!

[Muon321]

I am confused about group velocity, phase velocity, and signal velocity of waves. Which of these would be the velocity of the corresponding particle to that wave? And, what's the difference between signal and group velocity? Is there a difference?

[Izzy_Bee]

Hello, I just want to point out that a question like this can be broken down, into a couple and you can yield some fantastic answers from books and the internet, that have some good examples and great definitions.

You should bare in mind that there are a lot of ways to explain a wave and it's behavior, and this is simply because there are many different waves kinds to consider.

Group velocity = velocity that the wave packet moves through the medium in question.
Phase velocity = velocity that a single market node or anti-node moves through the medium in question.
Signal velocity = velocity at which information carried by the carrier wave propagates through medium. This is usually equal to the group velocity, if the medium is linear for example.

When asking if there is a difference between group velocity and signal velocity, it's some what like asking what the difference is between a single banana and a group of them! There is a difference, that's why they have a different name, it's just hard to see or explain unless you can visually show it to the person with animated illustrations, hopefully my description of them will help you see the difference.

Either way, hope this helped.