Recent content by neurobio

Thank you all for the answers. It now makes sense. I'll still have to open a book, though. The first thought that came to mind was "but wouldn't that require a photon to split into multiple photons - i.e. if a single photon of 200 nm light is detected as 400 nm, we would need to have two...

It kind of makes sense, but I think I'm reaching the boundaries of my understanding. To go further on this, I'll need to crack open a few math and physics textbooks. Oh well, that is what libraries are for... :) Thanks again for the explanations. :)

Thank you both, the general explanation makes sense. I do have a sub-question, although feel free to ignore it if the answer is too complex for forum explanations: what is the energy converted into? In the analogy with the ball, the potential energy is still available (I can let go off the...

A very basic question (I hope this is the right place for it). A distant star emits, say, a high-energy x-ray. Due to expansion of space, this reaches us as visible light (say, red part of the spectrum). The light that reaches us has less energy per photon (E=h*nu) then the light emitted...

Thanks! :) With this explanation and a bit more thought, I figured it out.

I highly appreciate these answers, but I'm still managing to stay confused. Sorry. :( Perhaps the problem is this: I'm not talking about the reality (I can grasp that there is one underlying reality, as described by spacetime intervals). I'm confused by what the observer would see. In...

Thanks! I'm still a bit confused at the third point (I don't quite "get" the answer to the Bell's exercise, so please bear with me). Let's simplify the issue: one rod, AB, length x. It accelerates, then stops accelerating, traversing 10x during the acceleration period. Then, when there is...

A few "paradoxes" in STR As you can guess from my username, I come from a biology background. I've recently had the dubious pleasure of discussing evolution with a guy who is also a major physics crank; now, my physics is good enough to dismiss most of his nonsense, but he gave me pause with...