Larrythesphericalcow

What do you think is the most interesting celestial body and why?

Also any advice for someone older who wants to become a physicist?

Thanks for the great answer.

My favorite is Proxima B.

What else is there before that? Addition and Multiplication?

To be fair when most people talk about linear algebra they mean something a bit more advanced then the Algebra one would learn in high school.

Most people will never learn linear algebra so good for OP for taking the initiative to learn it. Although commenting on qunatum mechanics the way he is before fully understanding math that a first or second year physics undergrad would take is pretty inexcusable.