Recent content by phina

I actually read QED about a year ago. I watched that part of that lecture, where it seemed Feynman basically said "Why does it work this way? I dunno! No one does!" so... I guess I'm not finding my answer, haha.

But.. argh. It's so frustrating. This seems like such a simple question, but there doesn't seem to be any simple answer. What is amplitude, then? Anyone know of any books that'll talk about this with some depth, but for a beginner? All books I've read have just sort of... mentioned it briefly...

Oh god, I have a feeling I'm getting myself deep into things that are way, wayy beyond my level.

Oh, okay. Though I still don't see why it's necessary to square it, rather than just... make it positive. Another question: The amplitudes of waves can interfere with each other... but probability can't, of course. That wouldn't make sense. Why?

You only lose the sign? So x+iy = |x^2 - y^2 + 2xyi| ? But... how? Are these just properties of complex numbers I'm completely unaware of?

But why is probability density equal to the amplitude of the equation? My objection comes from RedX saying that squaring a complex number still gives you the important information. I just don't understand where amplitude comes from, since the wave equation is not "real" and is just a...

Is it just a semantics thing? Does "squaring" a complex number actually mean multiplying by its complex conjugate? And if you multiply (a+i) by (a-i), wouldn't you end up with (a^2 - 1) which is still not what you started out with? Sorry, sorry, please bear with me

Could you by any chance expand on the second paragraph? How are you not changing important factors? If you have a+i, and you square it, would you not end up with a+2i-1? Am I completely misunderstanding complex numbers?

We started Quantum Physics in class, and I tried working out the Schrödinger Equation (not mathematically, of course - that's far beyond my level. Just the vague concepts) I understand it's basically a function that shows how something changes in time, and a snapshot of it at one particular...