Recent content by Sumo

But why do you insist on an absolute measure of distance? One of the premises that you agreed on was that this doesn't exist. Yet here you are talking as if the distance measured standing still is somehow the only real one.

Because as Doc Al pointed out, you sitting in your ship would only see the distance to your brothers ship as being 0.66 LS. And this distance is real; as you said, there is no absolute frame. So the fact that you measured the distance between the ships to be 2ls is only 2ls from a particular...

I just finished reading "Quantum Mechanics: A guide for the Perplexed", that was an excellent book. It might be a bit basic, but as far as explaining many of the concepts of QM in an easy to understand way, I haven't found better.

Well that's what I assumed was the case, originally. But take the example I gave above: LostConjugate seems to be disagreeing with you, I think: He seems to be suggesting that the presence of the original spaceship somehow causes the twin's clocks to behave differently. And I don't see how.

I'm using this because I'm trying to visualize the problem, and I haven't done much study using geodesics and spacetime curves. I will look into it though. Well this is exactly the question I raised in my first post. Regarding the twin paradox, what should have been an acceleration from twin...

Well what I mean is, imagine a scenario with the Earth and a spaceship some distance from it. The Earth is hit by an asteroid which causes it to accelerate and drift away from the spaceship. Now because the Earth is the one that accelerated, a clock there would run slower than on the ship...

I was just working on my knowledge of the twin paradox, and had a question that I couldn't find an answer to anywhere: If I understand it correctly the paradox is resolved because the two frames are not symmetrical, one is non-inertial, so that frame has it's clock run slower. So if you carry...

"When the Wind blows" That movie will make you want to blow your brains out. But Requiem for a Dream is definitely the most intense movie I've ever seen.

I was wondering the other day why we need to find a quantum explanation for gravity? Why not just try to take the QFT and put it on a curved spacetime, and see what happens. That was how I came upon quantum field theory on a curved spacetime and semiclassical gravity. My question is...

I know there are a lot of these questions, but please bear with me, I couldn't really find these precise scenarios elsewhere. First of all, am I correct in saying that if we took a distant galaxy that was highly redshifted, and had it emitting light pulses to us once every second from its...

http://www.youtube.com/watch?v=fJ-D5AUGVcI&hl=de" http://www.youtube.com/watch?v=inzgHjEVxAc&feature=channel" http://www.youtube.com/watch?v=WD3BWt85bxA&feature=channel" http://www.youtube.com/watch?v=YXDSCEX5wE8&feature=channel" http://www.youtube.com/watch?v=YX30dxKdJkc&NR=1"...

I think Lewis Epstein puts it best in his book "Relativity Visualized". He then goes on to describe the myth that is the one being discussed: That time runs slower in objects moving faster because objects are always moving through time at the speed of light, and must devert that speed to...

Well, if you take the Earth to be an isolated system. Life requires the sun, which involves a huge increase in entropy, to sustain it.

Thank you everyone, that's helped a lot. If you'll indulge me just a bit longer, so I'm sure I understand this correctly. Is this because the wavefunction for a single particle 'expands' over time? Meaning, the probability of finding a particle in one state becomes less likely over time...

Hello. Obviously I have only an amateur understanding of physics, but I am trying to gain a bit more knowledge about the concept of quantum spin. I understand that 'spin' does not refer exactly to angular momentum, but I believe more to a kind of mathematical degree of freedom which has...