Recent content by Mr Wolf

Ok, first of all, I think it's one of the most important experiment ever made in Physics. ...Even if I don't understand clearly the "why" and "how", even if I do agree that the "why" is something that goes beyond Physics and Science in general. Having saing that, as far as I've understood, the...

What about when you make the double slit experiment shooting one photon or one electron at the time? Why do the photon or the electron pass through the slits and form an interference pattern, instead of being absorbed by the screen in which the slits are created?

I can't believe my whole island (Sardinia) didn't exist 20 million years ago! ...And that at that time it seemed "stuck" to France. ... ?:)

Well, I guess I get what your point is: that is, if I move along the surface of a sphere I don't actually reach an edge. :eek: As far as I've read and understood (I studied Physics many years ago, but not Cosmology and Astrophysics), there's not an empty space in which the Universe expands, but...

Sorry, I'm a bit in a hurry now. But... you're talking about the example of the Universe expanding like a balloon?

I don't know if it's a tricky question, but a sphere is a 3 dimensional object. :biggrin: However, I'd say where the edge begins depends on the length of its radius.

What's there, then?

Well, M1 and M2 which appear in Newton's law of universal gravitation are the "property" (gravitational mass) of a body so that two bodies can actract each other, while the M2 which appears in Newton's second law of motion is a different "property" (inertial mass) that causes a body to oppose to...

I have a very noob question. Let's suppose to be at the edges of the Universe, and there are objects which produce light, like quasars, stars or whatever. So, what happens to the light that moves forward (not toward the inside of the Universe)? Where does it propagate? Does it "generate"...

To make things a "little" more complicated, it's interesting to point out that, when you compare the two laws, M1 and M2 that appear in Newton's law of universal gravitation are conceptually pretty different from the M2 that appears in Newton's second law of motion. :biggrin:

What movie was that? Googling it, I couldn't find it. :/ Some times ago, I watched a movie called "Another Earth", in which a "copy" of the Earth was discovered. Then, there is "Melancholia" (by von Trier - one the worst directors ever ?:)), in which a planet from nowhere is going to collide...

Thank you! I was just reading that topic right now, searching for Okun's name here! That article (even if it's quite old and I can't even say if it's right or no) stuck in my mind, when I studied physics, many years ago. Reading a discussion about it is quite impressive to me.

Without entering into the discussion, I just want to mention two articles. One, that I read for the first time many years ago, is: Lev B. Okun - The concept of mass (Physics today - June 1989) - If you search, you can find it online. I also found another more recent articles by the same author...

I think this thing came to my mind some times after I studied Electromagnetism when I studied Physics; otherwise, I would have asked it to my professor. (Incidentally, I'm still studying and I'm involved in Electromagnetism, but for a totally different course :wideeyed:) We know from Coulomb's...

Yeah, but it's the Math behind that discourages ...and too much Maths burns out the brain.o0) Ok, later I'll open another thread. I'll try not to be too naive.