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[Neruz]

Not really problems per-say, the correct answer to "Which way is the Electron spinning" is "Yes"

Human logic tells us something can't be two things at once, but why should the Universe conform to Human logic?

[andrea]

I like to think that it spins in a direction but we just will never be able to determine which is, which means that we have to say it is spinning in both directions. That however, is just personal opinion.

universe shouldn't conform to human logic of course. The problem is that humans HAVE to, which means that at some point the answer to "which way the electron is spinning" becomes " the electron isn't moving, my head started spinning".
we seriously need the cultural equivalent of a big kick in the posterior part of our body so that quantum physics become easier to accept. Which means they are easier to study too, for most people.

[alway]

Well, quantum physics obviously can not be correct. After all, the aliens in episode 16 of Stargate SG-1 said so! 

I, unfortunately, do not have a good or even rudimentary understanding of quantum theory. Although at this point in time, it could be argued no one really does... However, considering the theory is likely to change dramatically in my lifetime, if not the next few years, it almost seeems as if learning it would be pointless for the moment. Although I get the feeling this will be a year in which my curiosity drives me to study the very small. The question I find most interesting is whether current quantum theory is approaching the basic principles of the universe... or if it is turtles all the way down.

[shadow_slicer]

Also, something strikes me as odd. What exactly prevents you from continuously accelerating if the lightspeed is a limit only for an outside observer? Sure, for the observer your acceleration quickly approaches zero as you approach lightspeed, but if you keep accelerating, to you it should seem that you keep going faster and faster.

Nothing keeps you from accelerating. And if you calculate your speed based on stationary distance measurements and your accelerating time measurements, you will perceive that you continually accelerate towards infinite velocity. If you measure things like that, with separate reference frames, then the speed of light would seem essentially infinite (since you will never go faster than light). If however you use the same frame of reference for distance and time, you will find the speed of light is still c, and you are not moving faster than the speed of light relative to any single reference frame.

Edit: Just because we assume the speed of light is the limit, it doesn't mean it is. Think: We call it the limit because light is the fastest thing we have seen. It is the only thing we can see. So, technically there could be ways of faster travel, an unlimited amount, but we cannot see it or detect it unless it abides by the effects of light, otherwise, it'd move so fast, it would literally be invisible.

There is a theoretical particle that supposedly moves faster than light: the tachyon. This particle apparently has imaginary mass and travels backward in time. No one has detected this particle, and Wikipedia says that most physicists think that it is too unstable to exist. If it does exist, it probably doesn't interact with normal matter (otherwise it would violate causality).

If anyone is curious about more of this stuff, a good book to get a simple non-mathematical explanation is Einstein's Universe. That was the book I read for an introduction to this stuff, and I haven't seen something better.

[alway]

I learned it from The World of Physics, Volume 2 by Simon and Schuster which I read in elementary school. I found black holes very fascinating, and as such, I went into middle school with a moderate knowledge of relativity. I was awesome as a kid. 

[Flaede]

Ok, all you cats talking about That Damn Cat and electrons:
I know that this is a step back from the stuff you have been laying on up here, but I have trouble with something basic that gets in the way of following the less basic. The problm I have is of there being two states, with no in-between. The here or there, one spin or the other, and there is no inbetween.

Isn't this the same as the earlier talk of continuous and non-continuous functions? That it must work for all points? how can it be here, there, and never inbetween? Is it just that "the math sez so" (which I'd regretfully accept), or is there some handle in reality that this can hang on?

[Idiom]

Intermission:
There's a theory that antimatter is regular matter traveling reverse in time. When it collides with regular matter and is "annihilated" that is actually the point that it reverses it's chronological direction.

Where did I read this? I can't remember.

Another intermission:
A time machine that is actually being built relies on lasers bent into a loop. The light like this has the right properties to twist space-time, or so they say.

[ChairmanPoo]

A time machine that is actually being built relies on lasers bent into a loop. The light like this has the right properties to twist space-time, or so they say.

[citation needed]

[Grek]

Btw. Black holes. If it wasn't for all the random atomic crap orbiting them, they'd be perfect for catapulting off into space with the gravity slingshot. Or not. I suspect the gravity gradient would become too steep near the thing's surface, and the ship would be quite effectively torn apart when its bow starts to weigh twenty million times more than its aft.

I read a book a long time ago that if you had a rotating black hole, it would be possible to fly into it at exactly the right angle and go "somewhere". Where that "somewhere" is isn't really certain, as the math for it gets really, really funky. The author was suggesting that it would, from the veiwpoint of an outside observer, instantly teleport you to a location in the universe determined by the location of the black hole and your entry vector. It was really weird.

Also, something strikes me as odd. What exactly prevents you from continuously accelerating if the lightspeed is a limit only for an outside observer? Sure, for the observer your acceleration quickly approaches zero as you approach lightspeed, but if you keep accelerating, to you it should seem that you keep going faster and faster.

The only thing preventing you from accelerating would be the rapidly increasing mass of the ship as you approach lightspeed. Increases in speed result in increases in energy which result in increases in mass. As you go faster and faster, you need more and more energy to continue to accelerate at the same speed you were accelerating at.

[DreamThorn]

And I could recommend 'A briefer history of time', by Stephen Hawking.

The part where antimatter has a negative time-direction is on page 112.  It speaks of Feynman's quantum mechanical calculations.  I may have made a mistake when saying negative mass, but, AFAICT, rest mass and time-rate is the same thing.

Just because a theory is found to be inaccurate does not discredit the theory's inventor.  Otherwise we wouldn't still be teaching Newtonian physics in school.

Understanding quantum theory requires only understanding that you cannot know everything at once.  Knowing one thing makes other things uncertain.  Although, with entanglement, this sometimes works the other way around.

Understanding special relativity requires understanding that all movement is relative, the speed of light (in a vacuum) is constant and that relative motion implies relatively warped frames of reference.

The reason why I keep making mistakes with relativity theory is that it has been 8 years since I last studied it thoroughly.

And, regarding my unorthodox ideas, I try to keep them out of the discussion, but they slip in because I have been thinking about them for years.  I already take them as fact even though they have not been through peer review, which is wrong of me.

Proving that we are handling zero incorrectly is real simple though:

f(x) = x
g(x) = x - 1
h(x) = f(x) / g(x)   => has an asymptote at x = 1
h(x) * g(x) = f(x), except, at x=1 it has no value.

Shouldn't dividing and multiplying with the same value return one to the original value?  I am quite certain that has to be in the definition of division somewhere, and that it should count for all real numbers.  Maybe I should look it up.


Edit #1:

@Flaede:  Usually it is not so much a case of one state or the other, but, as you confine things, the total amount of valid states decreases.  So, for instance, in an unbound atom there are only discrete energy levels for electrons, because they are confined tightly along all three spatial dimensions.  In a conductive crystal (like metals) there are bands of valid energy states, with gaps between them.  In the case where an electron is not confined at all it can assume any energy.  Hopefully this is clearer to you now.

In the case with the cat, it is not so much that the cat is both alive and dead, but rather that the one bit of information regarding whether the cat is alive or not can have any value until the external observer opens the box.  From the cat's perspective things are quite different; the cat knows when it is alive and whether it dies.

@Idiom:  Bending a photon into a circle requires a significant warping of space-time.  I guess you might have misunderstood the original article.  (Bending due to matter-interference is another thing entirely, and will not cause warping of space-time.)

@Grek:  Your explanation of the acceleration limit is only valid for the observer staying behind.  For the person in the spacecraft it will seem like he is constantly accelerating, his mass staying constant, and gaining energy in accordance with that.  (IIRC)


Edit #2:

I've looked up the use of zero and infinity.  It has already been found useful and rigorously examined; in 1966 Abraham Robinson published the details.  http://en.wikipedia.org/wiki/Ghosts_of_departed_quantities

[Neruz]

A time machine that is actually being built relies on lasers bent into a loop. The light like this has the right properties to twist space-time, or so they say.

[citation needed]

I remember that actually, the theory was to create a 'tunnel' of lasers, which did some freaky shit to time and space and in theory should allow you to fire electrons down one end of the tunnel and they would emerge at the point in time when the tunnel was last turned on.

I'll see if i can find it.

[Il Palazzo]

Hope that made some sense.

Yeah, thanks. It's much clearer now.

[Sean Mirrsen]

Btw. Black holes. If it wasn't for all the random atomic crap orbiting them, they'd be perfect for catapulting off into space with the gravity slingshot. Or not. I suspect the gravity gradient would become too steep near the thing's surface, and the ship would be quite effectively torn apart when its bow starts to weigh twenty million times more than its aft.

I read a book a long time ago that if you had a rotating black hole, it would be possible to fly into it at exactly the right angle and go "somewhere". Where that "somewhere" is isn't really certain, as the math for it gets really, really funky. The author was suggesting that it would, from the veiwpoint of an outside observer, instantly teleport you to a location in the universe determined by the location of the black hole and your entry vector. It was really weird.

At just the right angle, you could be catapulted at the speed exceeding that of light. To an outside observer, you would have teleported. The problem with that is stopping. And, you know, being torn apart by gravity.

Also, something strikes me as odd. What exactly prevents you from continuously accelerating if the lightspeed is a limit only for an outside observer? Sure, for the observer your acceleration quickly approaches zero as you approach lightspeed, but if you keep accelerating, to you it should seem that you keep going faster and faster.

The only thing preventing you from accelerating would be the rapidly increasing mass of the ship as you approach lightspeed. Increases in speed result in increases in energy which result in increases in mass. As you go faster and faster, you need more and more energy to continue to accelerate at the same speed you were accelerating at.

But isn't lightspeed relative? Relative to yourself, you wouldn't gain mass as you accelerated, and unless your propulsion system is somehow exempt from relativity, its properties would increase just as well.

Also, I've thought about the laser-interference experiment, and could only come up with the half-assed assumption that lasers are a special case in mechanics. Just as you could send concentrated pulses of air that breached the speed of sound, lasers and their coherent resonating beams could make light travel faster than the compression threshold for the energy medium. Also, the Earth's magnetic field likely has an effect. After all, it even stops the much more intense solar wind. We'd have to conduct the same experiment out in space, unshielded, and perhaps without lasers, which would in itself require some serious engineering ingenuity. Such requirements also make me sound very cheap. I'm too lazy to look up what aberration is right now, but supposedly the theory will have to explain it as well. That'll have to happen later.

[Il Palazzo]

Keep in mind, solar wind is a fancy name for particles(H, He) ejected from the sun. It's not photons.

[Sean Mirrsen]

Yes, otherwise it'd be pretty dark in here.

But magnetism does have an effect on light, last I heard. I hate to uphold the aether thing, but using its principles, the "speed of the stream" around us is a tenth of a percent of c, and our magnetic field could easily repel that.

Also, unless memory fails me again, the Earth's magnetic field is also affected by the radiant energy from the sun. If anything, the Sun's radiance would quite literally blow all the aether away from it, and instead of basing aether speed on orbital motion, we could base it on position against the sun instead. Which has unfortunate implications of its own, like gravity and penetrating radiation that can't easily be shielded against that would contaminate any outer space experiment.