As I understand it and will attempt to clarify David Barclay’s position, picture experiment participants Alan, Bob and Charlie. At a signal from Charlie, Alan shines a flashlight at Bob, who reports the exact time he sees the beam of light. Charlie makes various calculations to derive the speed of light; a nice constant 299,000-ish km/s. Now put Alan and Bob on a spaceship and rocket them past the relatively stationary Charlie at 0.999… c and repeat the experiment. Will Bob observe a different result? Will Charlie?
As I understand it, most of us will say “no and yes”, while David maintains “yes and yes”. Of course, I may be way off, having forgotten to carry the one, or something.
Bell’s inequality and the double slit experiment are both concrete evidense for the same weirdness. Instead of information not being able to travel faster than the speed of light (which, without the ether we haven’t found yet, it can’t), why not theorize that there is no transmission at all, but an inherent property of the universe (like the forces of gravity, etc). I am very skeptical of any physics math explanations that cannot be reflected in real experiments (a lot of quantum physics).
How easy/hard is it to entangle two electrons when performing an experiment? Converesly how hard/easy is it to not entangle them? I assume that the entangled pair must be generated or split off of the atom, etc. at the same time or the entanglement couldn’t occur.
As to “collapse of the wave function”: my macroscopic experience suggests that an entangled pair of electrons would simply be generated at one point in time with one Spin-Up and one Spin-Down. Then when measured later you would see one as Up and one as Down. It is “random” in that you don’t know which went which way because you don’t know anything until you measure. But it doesn’t seem mysterious. What is missing from this simple view?
My analogy is picking a black or white marble, putting it in an ideal hula hoop and spinning it around. Another person would have to cut the tube and see which color is in the tube. It is random from their perspective. A similar analogy is me putting two bouncing rubber marbles in the same ideal tube, starting the second one bouncing when the first one I tossed bounced into the tube. Whenever you finally cut the tube and make your measurement, one marble is black, the other white, one is bouncing up and the other bouncing down. My entanglement in the beginning causes all the correlation later, but no infomation is being exchanged to keep them correllated. What is missing here?
From my understanding (and again, I’m just a freshman physics major), the very point of quantum mechanics is that both of them have superposition of spins. That is, they both are spin-up and spin-down at the same time until you observe one of them. That’s the whole reason why a single photon can interfere with itself. It goes through both paths at the same time.
A lot of the explanations (if by explanations you mean the interpretations) cannot be reflected in real experiments, but the physics itself is, by definition, only that which is subject to experiments. In some cases, the experiments are very difficult to do, and the technology has not yet caught up with the theory, but if it inherently isn’t subject to experiment at all, then it isn’t physics, nor even science. This is, in fact, why many physicists prefer not to talk about the interpretations at all: There’s no physics in, say, the Schrödinger’s Cat “experiment”.
The original questioner said: “streets full of Middle Eastern men indiscriminately firing guns straight up into the air.”
Since your website is about ameliorating ignorance, I’m surprised you are unable to detect the ignorance, not to mention jingoist bigotry, of this statement. I live surrounded by rural white Americans for whom no better kick exists than to fire their guns into the air, usually after consuming large quantities of alcohol.
My guess is that American civilians kill more people with careless use of firearms than any citizenry on earth. Think about it.
I’m not certain to what you are refering. The original post in this thread said nothing of the sort, nor did the question to Cecil in the column that spawned this thread. Are you certain you are posting in the correct thread?
The response link on the above column doesn’t seem to work, or I’m doing something wrong. Anyway, I’ve begun a new thread, “More on falling bullets…”, for anyone who wants to pursue this topic. Thanks…
At parallel to the gun, the bullet would remain constant to that point. Stationary to the bullet, any direction but toward you, it would never be seen. What’s weird is if it was shot near you, first would be the impact, then the backwards view of the path back to the gun!! I thinks thats right?
I’m almost certain you’ve got this completely wrong. Time dilation is included (and is necessary) to preserve the constant speed of light - time stretches at high relative velocities because distance shrinks. The time/distance ratio thus remains constant.
I did not mention time dilation or refer to it. The speed of light as we presently perceive it is based on two things, a clock and a meter rule. If you slow the clock you slow the speed of light. If you extend the length of the meter rule you slow the speed of light. If you speed the clock up you increase the speed of light and if you shorten the length of the meter rule you increase the speed of light.
If you want to preserve the speed of light in relation to a constant, in that the speed of light is the same regardless of where you are in the universe you are going to need more than time dilation to preserve the constant speed of light, because the speed of light presently corresponds to a localized condition and is confined to a linear definition.
As the universe is not static, but is in fact dynamic, it is impossible to describe universe through the use of static linear terms other than as an imaginary concept.
The speed of light is the upper speed limit of any mass, in relation to a linear relationship. And in this respect the speed of light remains relative to the system of reference, whereby the speed of light is different for all systems.