physics.cpp

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Re: physics.cpp

Postby chuck_starchaser » Fri Mar 26, 2010 9:53 pm

Errol_Summerlin wrote:@chuck ah, at last I have met my counterpart, one who can match my long-windedness.
Hahaha, glad to have the honor. :)

chuck_starchaser wrote:Therefore, I believe that to change the speed of light in vacuum, you'd have to affect its dielectric constant
and/or its magnetic permeability, which may or may not imply a change in energy level; but I'd simply say
that energy level is a secondary issue at best. The trick is figuring out where these constants are produced,
or set, and find a way of tweaking them.

I don't think you need to qualify that with "I believe". Mu and epsilon determine the speed of light in a given medium. This is true for all materials. Changing them is obviously the key to changing the speed of light in a vacuum, but there is some question as to whether or not the maximum speed of massive objects would be changed by this. For example, air has a different speed of light than vacuum (n=1.0008). For highly energetic particles entering the atmosphere, they are traveling at speeds> c/n but still <c and they produce cherenkov radiation. However, the air slows the particle down to sub-luminal speeds very quickly. The question is, if the air was not there to slow it down, but the refractive index was somehow still 1.0008, would the incoming cosmic rays be slowed to c/n. When a light wave leaves a material with refractive index >1 and re-enters vacuum, it resumes traveling at the speed of light. This does not appear to happen for massive objects.
My gut feeling is that it would apply to particles as much as it does for waves; BUT, you'd have to take into account that refractive indexes are not constant; they are in fact VERY non-linear. Even for vacuum I'm not sure n would prove to be constant for ALL wavelenths... That's why prisms split light. It's also why if you calculate the refractive constant for water as the square root of its dielectric constant, you get a large number, but the refractive constant is actually pretty small.. !?!?! Why? That's because dielectric constants are usually measured at around 1 MHz, whereas refractive constants are mostly (if not universally) measured using visible light, at least for tables for practical uses.
If you compute the wave function of a Grayhound bus moving at 100 km/hr, you get a very short wavelength (tons of energy), and I doubt that n for air would read 1.0008 at that energy level/wavelength.

Energy level is too broad a concept. At its absurdest, it would imply that for waves to travel faster on the
surface of a lake, you have to kill all other waves. I don't think it would affect the speed of your waves
much, to have perfectly still water to begin with; though you would get a tiny benefit, I believe, from
some non-linearities in wave mechanics on water, which may very well apply to EM waves in space.
The "absurdest" is pretty much exactly what this paper showed http://arXiv.org/pdf/hep-th/9810221.
I'll check it out.
It is the paper referred to in the quote in my earlier post. Equation 10 is the relevant equation showing that the refractive index perpendicular to the mirrors is < 1. I am not an expert on QED, but it was accepted to a reputable journal which means that somebody who knows QED said this result was valid. Between the plates, the speed of light should be > c. If you are talking about water, this wouldn't work. Water molecules have mass and the molecules themselves are in excited energy states with far more energy than the vacuum. They also experience physical collisions rather than wave interference. Basically, the analogy that has worked well so far breaks down when you start talking at the quantum level.
Ah, some anisotropic modulation of n... Interesting.
There was an article in SciAm, about a year or two ago, about observations about the behavior of light-waves near the horizons of black holes that would seem to support the concept of space being made of "space particles"; --IOW, the article proposed that space has "structure".

I feel hinky about time being a "dimension" in cosmology as well, but the math works out and explains observations, so there must be some truth to the equations if not, necessarily, to their interpretation.
That's what I'm told every time. My counter-question is are those "working equations" necessary? Or simply may-be's, like Euclid's Fifth Axiom?

And where does all this tie with Vegastrike?

Nowhere. I was just trying to say that current theories are full of shit baggage and conceptual confusion,
and that in their present form they can't hope to point the way to a workable solution for FTL. We're going
to have to wait for a new generation of scientists more capable of critical thinking, IMNSHO.

What I would propose for Vegastrike, in terms of FTL, is some mumbo jumbo
This is where I have to differ. Yes, MANY of the theories are contradictory. None of them explain everything, and most of them cannot be proven in any way shape or form. But rather than just make some "mumbo jumbo" up, I prefer to find a theory that COULD be right and run with it to its logical conclusion.
Okay; I'm with you; but I think we'll be able to come up with a number of plausible models; and it may still boil down to game convenience. Just to go out on a limb, as a way of example: We don't know what causes inertial mass. Higgs particles?
These guys will have none of them: ag-physics: The Origin of Mass
Ever heard of the "kinemassic field"? Some guy (not a scientist by title or profession) supposedly built a machine to experiment with a theory he had about the strong force being related to the spins of the nucleons involve. So he built a big, heavy machine... A [] -like, square frame of copper, about 200 kilos. On the sides of the frame, he made cylindrical cut-outs, like ( ) turned 90 degrees, cutting through the sides of the frame. Inside those cylindrical spaces on both sides, he put precision fitting copper cylinders: one (on the left side) rotated around its axle by a motor that rotated it very slowly, like one turn per hour. On the right side, the cylinder could rotate freely. Each cylinder was actually made of two quasi-half cylinders with a one-inch gap between them. Inside those gaps he had precision-machined disks of copper, tightly fitting in the slots, and made to rotaty very fast by air-jets.
So, these fast-spinning copper torts were like gyroscopes, opposing having their axis being rotated; but they were suspended inside slots in the middle of beefy copper cylinders that, on the left side, forced the axis of the gyro to rotate slowly; and on the right side simply allowed the axis to rotate, if for some mysterious reason it wanted to.
He reported long tables of measurements.
Essentially, forcing the axis of the gyroscope on the left to rotate, seemed to cause the axis of the gyroscope on the right side to oscillate on its own, with a cycle matching the rotational speed of the gyro on the left; but this effect took several hours to travel from the left side of the frame to the right side.
Why copper? To rule out magnetism, and because according to his calculations, odd atomic number and an even number of neutrons would make it highly permeable to this force he postulated and claimed to have demonstrated.
He claimed that "shorting" the frame top-to-bottom with iron or steel had no effect; but that shorting top to bottom with a bar of copper completely killed the coupling between the gyroscopes.
I don't know if I believe it or not; just something I read and I "shelved" in my mind. And I'm not sure if it would relate to mass.
Now, let's assume it were true...
Perhaps rotational inertia has something to do with the random orientations of counter-spinning pairs of nucleons, and if we could force them all to line-up, perhaps with a very strong "kinemassic filed", maybe rotational inertia might become anisotropic?
Perhaps as rotational inertia vanishes around one axis, linear inertia might go away along that same axis? I think that to postulate such a thing for game purposes would probably be good enough, with a whole book's worth of history full of imaginary experiments to go with it.
There was also the physicist that lectured at a convention I attended in Atlanta, many years ago, who presented an entirely new understanding of what a particle IS. To him, a particle was essentially a trapped wave. Trapped in what? In a tiny relativistic bubble. He was saying, paraphrasing, "if I'm standing in the middle of a circular platform that is spinning so fast that the perimeter is going at the speed of light, and I step away from the center, I start to accelerate towards the edge; but once I reach the edge I start moving backwards...", or something along the lines. He classified fermions, bosons, by the number of wave-lengths within the trap, and he obtained consistent figures for spin, charge and... yep, mass. To him inertial mass was simply a consequence of wave-pressure differentials on the "walls" of the relativistic trap, as the particle is accelerated.
The only requirement for this theory is that A) it has not been proven obviously and catastrophically wrong and B) its logical conclusion works for gameplay.
Exactly.
In essence, I selectively picked one of the theories out there to suit my gaming needs instead of just making one up that suits my gaming needs.
Keep in mind that scientists are forever terrified of getting a bad name by "going too far". Essentially, they can question up to 1.25 assumptions of the Standard Model, or accepted cosmology, but not question anywhere nearly 1.75 assumptions in one paper. But I suspect that many suspect assumptions come in pairs; and, anyways, that makes it difficult to find very imaginative theories, however plausible and sound they might be. Lots of self-censorship.

The casimir effect and its implications for the local speed of light are a proven effect. If we could find a way to kill off all the harmonics and not just a few in the perp direction, we could substantially change C within that medium. Our manipulation of em waves is getting pretty good now. The invisibility cloak is coming along nicely. (They have light travel around the wearer and come out exactly on the opposite side instead of hitting the wearer.) I used the analogy of the sound-canceling technology on cars by way of explanation. Obviously any sort of em harmonic killing emissions would be substantially more complicated, but based on the same principle.
Doesn't the speed of light slow down a great deal in bose-einstein condensates? Yet there's no huge energy concentration in them; in fact they are near 0 degK. I'm not doubting casimir; I'm just not sure that "energy" is the key. I'd be more inclined to suspect refractive index anisotropy. Wonder if anyone's measured the speed of light in pyrolytic graphite...

that allegedly allows us to
reduce the inertial mass of a ship, but leaves its gravitational mass untouched. Whether that involves
producing "anti-dark-matter that disperses through the ship cancelling mass", I don't care, but the benefits
of inertial mass reduction are just too great to ignore:
  • Increases acceleration per unit of impulse
  • Increases SPEED without spending energy!!! --conservation of momentum dictates that speed must go up as mass is reduced
  • with non-modified gravitational mass, gravity would be stronger relative to inertia/centrifugal force, so ships would use sling-shot maneuvers and stuff in spite of great FTL speeds, making the over-all effect similar to time-compression, but without the game-busting implication of years of planet time having elapsed during your short trip.
These, I say, are too many advantages to mass-reduction-based FTL to ignore it.


If we are just making up "mumbo jumbo" anyway, it is best not to put too much physics into it. Just multiply deltaX by some factor X every time step when the thing is on, eat X times as much power while it is on and be done with it.
Well, I would agree it would be super-cool if people in the 3rd millenium study in school about a game called Vegastrike which postulated a theory that turned out to be true and allowed humanity to travel to other stars. :D Failing that, I'd look for some believable AND plausible mumbo jumbo to explain inertial mass reduction.
If the relativistically trapped waves guy is right, we could "jump" TO the speed of light, I reckon, simply by accelerating all particles to the speed of light at once in a given direction.
That would necessitate that we first colinearize and synchronize all the trapped waves, so that they all move forward and all move back in unison. As the wave of every particle is passing through the middle of the trap in the forward direction, with very small energy (>>zero) we can accelerate the whole ship forward to the speed of light. The waves and their relativistic traps move forward together as if frozen. IOW, time stops. Which is what travel feels like to a photon. Now here. Instantly elsewhere (12 billion years later).
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Re: physics.cpp

Postby chuck_starchaser » Fri Mar 26, 2010 10:13 pm

Neskiairti wrote:Chuck:
I agree with you 100% about the issue of time. I seriously hate that people try to lump time in with dimensional theories.
there are so many concepts for FTL, any of them would work really. Mass Cancellation is a good one.
Glad to hear I'm not alone. Seriously, you're the first person I meet that agrees with me on this. I had a friend, or acquaintance, that we started arguing about this; he was a physics graduate; and, after 4 or 5 times we met to argue, he reluctantly admitted that time doesn't behave "exactly like the other dimensions of space", but to him there was no question about the continuity between space and time, and insisted that "why they 'appear' different is the question that needs answering". And the reasons for his unshakeable faith was that "equations work so well" [that mix them together as a continuum]. That's no different than people putting complete faith on superstring theory just because it's "elegant", IMO (after which they all jumped onto "branes"; --but none of them understands the difference between an N-space and an N-manifold... They use the terms as if they were synonyms...)
That time has "extent" is a matter of faith on clocks; --and not just on their accuracy, but on the meaning and implications of the nature of what they allegedly so accurately measure.
To me, time has only one Real extent: a SIMULATION_ATOM... err... TIME_STEP (one Plank's Time?); and all other extents and measures are just frame-counters of various accuracies and sophistications.
But I understand this would shatter the premises of crime and punishment, etceteras, if we could say that the past is no-more, and therefore the question of what really happened is irrelevant, if perhaps arguably meaningful; so there are social and political pressures for time having extent; but they don't make it true.
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Re: physics.cpp

Postby chuck_starchaser » Fri Mar 26, 2010 10:53 pm

People say that quantum physics' "observer affecting result" is somehow impossible to understand.
I'd rather put the focus on human understanding; an I have a perfect example of a human scale phenomenon
where knowledge alone appears to affect a probablility. This was related to me by my boss: There was a Mensa,
highest IQ people TV show, where high IQ people were being asked tricky questions to see how well they fared.
And there was a lady that had a super-high IQ and she was asked this:

You are at a TV game show. You are shown 3 closed doors, and told that behind one of the doors there is a
prize to win, if you pick the right one. So, you pick a door at random.
Now, the show's host says that to make your choice easier, he will open one door, and he opens one door, and
there's no prize behind it. Of course, he knows where the prize is, so the door he opened, he knew was not
the prize door.
Now he gives you a chance to change your mind...
The question is, should you,
  • Stay with your first choice?
  • Switch to the remaining closed door?
  • Does it matter?
I said at once to my boss, "it doesn't matter; the probability is 50-50."
Well, the high IQ lady said one should switch to the last door; and her answer was right.
But why?
It turns out the probability that her first choice of door is right still remains at 33.3%, whereas the probability
that the last remaining door is the right one is now 50%.

It took me about 4 years to figure out why this is so.

Hint: Change the setting to there being 100 doors. You pick one. Then the host opens 98 doors, and gives you
a chance to stay with your first choice or switch to the other door. You see now why the other door he left
closed is more relevant than your first choice?
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Re: physics.cpp

Postby Deus Siddis » Fri Mar 26, 2010 10:55 pm

Actually I haven't bought the "time is a dimension" theory either, since I was like 14. Because the first three dimensions make up space, and on each axis I can travel in either dimension at will. With time, everything flows always in one direction and always at the same rate. Not at all like things, IMO.
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Re: physics.cpp

Postby Neskiairti » Fri Mar 26, 2010 11:32 pm

HAHAHA.. I spent two weeks trying to explain the monty hall phenomena to my room mate, a year ago. He just couldn't grasp that even though there was now only 2 doors, the first door was still 33%. I even tried to explain it with 100 doors, but still no.

I think you know me well enough, to know I fail at math, horribly. I'm pretty sure i expressed that to you through correspondence.

Anyway, I think it is that very fact, that I have trouble with equations yet have a very strong grasp of physics that allows me not to be lured by the concept of time.
Yes, time is just a measure of that universal (or perhaps less universal) ticking.
for instance, particles move and interact, that movement eventually allows us to think and perceive. the slower that happens, the slower 'time' is for us. I have always pictured the time dilation stuff as simply, something having to due with movement across the surface of space causing particles to interact slower. For all intensive purposes, that is time slowing, whether it is something like friction against the surface of space dragging particles farther apart so it takes them longer to oscillate or what not.. it really doesn't matter, its going to have the same effect.

anyway.. Theories can be elegant and still wrong, some theories can be ugly as fuck, and be right. People settling for a theory without challenging, that is the cause of technological stagnation.
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Re: physics.cpp

Postby chuck_starchaser » Fri Mar 26, 2010 11:37 pm

@Deus: Exactly. And if time was "THE fourth dimension of space", then what's "THE first dimension"?, "THE second"?, "THE third"?, ...
The proverbial three dimensions of space can be picked in any arbitrary rotation; but you can't turn a long-lasting metal ball 90 degrees such that it turns into a short-lived metal bar.
But the ultimate absurdity of the time-as-dimension model is the postulation that the perception of change is due to "consciousness moving along the time dimension". At what speed is consciousness moving through time?, and in what units would such speed be quantified? Seconds per second?
Plus, the lack of evidence for the past still existing or the future already existing.
IMO, the concept of "space-time" is a matter of irrational faith held with religious fervor.
Much of it boils down to people liking Albert Einstein, and if he believed in "space-time" it must be so; but he was dead wrong more than once, and that's well known, so it doesn't make sense.

@Neskiairti: Good for you! Indeed, Relativity is not so hard to understand. The example of the two mirrors on a space-ship says it all. Light is reflecting off the two mirrors as a way to measure time, but as the ship approaches the speed of light, the light is zig-zagging at very shallow angles between the two mirrors, so the clock is going slower. Where people don't make the connection is that "light bouncing between two mirrors" is a metaphor for all physical, chemical and physiological processes, which are mediated by forces, which are mediated by exchanges of particles. So ALL clocks (artificial AND natural) slow down in unison, so you become so slow that the slow clock seems to be going at its normal speed.
No rocket science... :)
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Re: physics.cpp

Postby Neskiairti » Fri Mar 26, 2010 11:46 pm

aye, even Einstein knew he wasn't all knowing :P he was just smarter than the rest of the kids. and I thank him daily for his contribution to my favorite genera. (so many delicious concepts!)

another concept of the speed of light that always amuses me. Our galaxy is already traveling through space at such tremendous velocity. how fast? no idea, but fast.
So if we try to reach .99C going ahead of the galaxy, we will not get very far very fast. If we go the other direction at 99C.. then what, are we traveling (relative to the galaxy) at ~1.5C? and it will take us even longer to get back.

yet people always talk about the trip at .5C to and from a destination, as taking the same amount of time... it wont unless we are directly 90 degrees from the vector of momentum our galaxy is on.

ahh you edited, so i edit to your edit!

yes, its not rocket science, its a bit harder to comprehend than a couple volatile compounds and a vector :p

but really, the hardest thing to under stand is this god damned ogre documentation! its worse than Vegastrike documentation!
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Re: physics.cpp

Postby chuck_starchaser » Sat Mar 27, 2010 1:03 am

Another thing that gets me is the rampant contradictions in cosmology. Calculating from red shift, the furthest galaxies appear to be receding at faster speeds than the speed of light. So the self-appointed fire-fighters jump to explain that the popular view of the universe expanding linearly *through* space is a misconception; and that the theory of universal expansion is that space itself is stretching; and that galaxies are like stationary pimples on the surface of an inflating balloon. I'd almost bet money Mr. Hubble was NOT thinking about balloons. The nature and spirit of his theory have been changed completely --would you say co-opted?
Popular misconception my ass! That's a *new theory* altogether.
But then we hear that the mapping of background microwave radiation proves that the universe is flat...
Well, the whole idea the mapping experiment was based on was the premise that the microwave background is the remnants of gamma rays that were produced in the big bang; and that the reason they appear as microwaves is that the waves have stretched due to the stretching of space; and the reason they are still kicking around is that they've gone around the universe multiple times...

Well, excuse me...

If those forsaken photons have been going "around the universe", it means your whole theory is based on the premise of the universe being closed (a closed manifold). If that premise led you to device an experiment whereby you proved the universe is flat... ahem... I guess your brilliant experiment proves that your premise was wrong to begin with, and therefore you experiment is garb... inconclusive.
Number two, if space is expanding at faster than the speed of light, even if it were a closed manifold, those gamma rays would never have cought up with the expansion of the universe to make it back here, whether as microwaves or as darkness of any color.
Number three: If waves stretch as they travel along this inflating balloon, I guess the light that reaches us from the furthest galaxies would be no exception; would it? So, if it left home 15 billion years ago, the age of the universe, supposedly, they should have stretched about as much as the gamma rays from the big bang have stretched to microwaves. No? IOW, we should see so much red shift as to think those galaxies are receding from us at 700 c perhaps. The fact that they only seem to be receding at 2.2 c would be indicative that they are actually coming towards us at 697.8 c.
Number four: How is it that there's two sets of universal laws? --one for galaxies, and another for background radiation?!! Galaxies keep getting farther away, but background radiation "keeps going around"...
Now, when that distant galaxy, 14 billion ly away, sent out the photons that are striking our eyes and telescopes now, how far away was it then? Well, if the age of the universe is about 14 billion years, 14 billion years ago that galaxy was poking us in the ass. So it can't be that the light we see now left that galaxy 14 billion years ago. What this implies is that 14 billion years ago, that galaxy WAS 14 billion light years away from us. Where it is NOW?, who the heck knows? But if we are getting 14 billion year old photons here, it means the age of the universe can't be less than 28 Billion years old. Can it?
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Re: physics.cpp

Postby Neskiairti » Sat Mar 27, 2010 1:17 am

-chuckles- I am reminded of a theory i read a few months back, which for the life of me I cant find or remember in entirety.

Essentially, the big bang didn't happen, instead the universe just stretches on and on and on in to infinity or something like that. a constantly churning mass of energy, strewn out across space. The universe that we think we know, is just a bubble of hot gas in a cloud of cold gas, the microwaves were seeing, is just the trailing edge of energy that made it to us through all that inter galactic dust.

something like that anyway :p
I prefer to think of the universe that way, the big bang always struck me as a god replacement.

We think in finite terms, but that doesn't mean the universe is finite. I can accept, even If I cannot conseptualize, a universe that was never born and will never die.

hum.. i think this thread has been completely derailed :p oh well.
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Re: physics.cpp

Postby klauss » Sat Mar 27, 2010 2:33 pm

Neskiairti wrote:HAHAHA.. I spent two weeks trying to explain the monty hall phenomena to my room mate, a year ago. He just couldn't grasp that even though there was now only 2 doors, the first door was still 33%. I even tried to explain it with 100 doors, but still no.

The game show is simply wrong.

Unless the lady had chosen a door the host already showed to be prize-less, the two remaining doors share a 50% chance of being right.

Both.

So even if you keep your previous choice you have 50% chances of being right. The chances changed, no need to choose again.

The problem is of conditional probabilities: the first probability (33%) is the probability of door 1 (suppose I choose 1) holding the prize. The second probability (50%) is the probability of door 1 holding the prize knowing that door 3 doesn't.

Now, all this ignores one factor: the motivation the host has to give you the choice. This shifts probabilities, but it's a risky move, since you have to gauge motivations accurately to win. If the host had anything to gain from you loosing, he'd probably give you the choice to make you choose another (he knows people is likely to choose another), and he wants you to choose another, because you chose the right one. It's not necessarily so, but there is a chance it is so. The other possibility is that he's doing it for the show. If you factor in those chances, I don't know the result, but it could be that it's in fact better to stay with your original choice.

EDIT: postulating time as a dimension works for the equations because the things being measured or predicted in those equations show correlation of time vs space coordinates. Ie: time and space aren't independent "dimensions" in data space. It doesn't mean time is, physically, a dimension. In fact, the fact that you can't turn a "short stick" into a "short-lived stick" is a nice paradox I'll be using ;) - and one that shows time is indeed physically different from the other "dimensions". Also remember that the word "dimension" only denotes a variable in math and statistics, nothing else.
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Re: physics.cpp

Postby chuck_starchaser » Sat Mar 27, 2010 3:57 pm

klauss wrote:
Neskiairti wrote:HAHAHA.. I spent two weeks trying to explain the monty hall phenomena to my room mate, a year ago. He just couldn't grasp that even though there was now only 2 doors, the first door was still 33%. I even tried to explain it with 100 doors, but still no.

The game show is simply wrong.

Unless the lady had chosen a door the host already showed to be prize-less, the two remaining doors share a 50% chance of being right.

Both.

So even if you keep your previous choice you have 50% chances of being right. The chances changed, no need to choose again.

The problem is of conditional probabilities: the first probability (33%) is the probability of door 1 (suppose I choose 1) holding the prize. The second probability (50%) is the probability of door 1 holding the prize knowing that door 3 doesn't.

Now, all this ignores one factor: the motivation the host has to give you the choice. This shifts probabilities, but it's a risky move, since you have to gauge motivations accurately to win. If the host had anything to gain from you loosing, he'd probably give you the choice to make you choose another (he knows people is likely to choose another), and he wants you to choose another, because you chose the right one. It's not necessarily so, but there is a chance it is so. The other possibility is that he's doing it for the show. If you factor in those chances, I don't know the result, but it could be that it's in fact better to stay with your original choice.

Klauss, indeed the host is the evil factor here. Think of it as 100 doors, instead of 3, and you'll see what's happening:
You choose a door at random, and your chance of being right is exactly 1%.
Now the host opens 98 doors.
But here's the thing: The host will NOT open the door that has the prize behind. NOR will he open the door you already chose.
That means that, assuming your first choice was wrong (99% chances), he will have to leave that door close, AND ONE more
door, which by elimination has to be the one with the prize behind it. He really has no choice on which 98 doors to open, because
he MUST leave two doors closed: the one you chose, AND the one with the prize; and MUST open all the rest. The chance that the
choice you made at first is the good one is still 1%. It can't have become 50% just because the host opened a lot of doors.
But the chance that the other door he left closed is the one with the prize is now as high as 100% minus the chance that your
first choice was right, so 99%. IOW, it is almost a certainty that the prize is behind the other door he didn't open.
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Re: physics.cpp

Postby klauss » Sat Mar 27, 2010 4:44 pm

chuck_starchaser wrote:He really has no choice on which 98 doors to open, because
he MUST leave two doors closed: the one you chose, AND the one with the prize; and MUST open all the rest.

No, that's not the case.

He MUST leave two doors closed: the one with the prize, and one more. One of the two has to be the one you chose... but there's no telling which. You could have chosen the one with the prize, and then he has a choice on which other door to leave closed.

But I'm beginning to see the reasoning... there's a 1% chance that you chose the one with the prize and maintaining your choice would be beneficial. And there's a 99% chance that you chose the one without the prize, and then the other one would be the choice to make. So the numbers favor choosing the other one.

But that's also wrong, in the sense that you're ignoring the new information when computing the probability of having made the right choice the first time: you now know 98 doors without prize, and now your chances of having been right are, indeed, 50-50. Chances only model uncertainty, and the host, by opening up doors, effectively changed the amount of uncertainty in your problem.

So... again... there's a 50% chance that you chose the one with the prize, and maintaining your choice would be beneficial. And there's a 50% chance that you chose the one without the prize, and then the other one would be the choice to make. Still 50-50.
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Re: physics.cpp

Postby chuck_starchaser » Sat Mar 27, 2010 4:58 pm

No, Klauss; you're wrong. Write a python program and convince yourself.
There's nothing special about the door you originally chose. The ONLY reason the host MUST keep it closed
is the fact that you chose it.
Whereas the other door MUST contain the prize, UNLESS you chose right the first time, and the chances
of that are still as small as they were when all the doors were closed.
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Re: physics.cpp

Postby Neskiairti » Sat Mar 27, 2010 8:33 pm

oh god klauss.. no.. dont start this argument up again D: i spent weeks at it.. yes, write yourself a program and prove it to yourself.

-edit-
and here is the final word of realism in video games: http://www.youtube.com/watch?v=9bKoahtmcHY
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Re: physics.cpp

Postby klauss » Sun Mar 28, 2010 11:01 am

No need to write a program - a formula is enough.
:p

But lets drop it.
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Re: physics.cpp

Postby chuck_starchaser » Sun Mar 28, 2010 12:13 pm

Well, I'm not sure how to put all of it in one formula.
But you can understand it by a reductio ad absurdo:
In the 100-door example, your initial chance of being right with your pick is 1%.
Can the host ***change*** that probability to 50% by opening 98 doors?
No.
The probability that you were right initially is the same: 1%.
What the host DID do is change the TOTAL (combined) probabilities to 100% for
two of the initial 100 doors.
One of them is the one you picked, and it still has a 1% chance of being right.
And one other door, whose probability is now 100-1 = 99%.
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Re: physics.cpp

Postby chuck_starchaser » Sun Mar 28, 2010 4:44 pm

Another way of looking at it:
Imagine you were playing the 100-door game 100 times.
Each time:
  • you pick a door (with a 1% chance of being right)
  • then the host opens 98 doors
  • you stick to your initial choice
Now, do you really think you'll win about 50 games?
Because that's the absurd conclusion your 50-50 mental model leads to...

It implies that the host's action of opening 98 doors somehow affects the chance of
the door you originally picked being the right door favorably. How would it do that?

If as a matter of policy you always stay with your original choice, the opening of 98
doors is irrelevant; decorative. Your best chances are of winning 1 game in 100.
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Re: physics.cpp

Postby Errol_Summerlin » Sun Mar 28, 2010 7:39 pm

My gut feeling is that it would apply to particles as much as it does for waves; BUT, you'd have to take into account that refractive indexes are not constant; they are in fact VERY non-linear. Even for vacuum I'm not sure n would prove to be constant for ALL wavelenths... That's why prisms split light. It's also why if you calculate the refractive constant for water as the square root of its dielectric constant, you get a large number, but the refractive constant is actually pretty small.. !?!?! Why? That's because dielectric constants are usually measured at around 1 MHz, whereas refractive constants are mostly (if not universally) measured using visible light, at least for tables for practical uses.
If you compute the wave function of a Grayhound bus moving at 100 km/hr, you get a very short wavelength (tons of energy), and I doubt that n for air would read 1.0008 at that energy level/wavelength.


The trouble with testing this is that most matter traveling through a medium experiences drag. The only way to test this would be to sending a WIMP like a neutrino through something with a refractive index >1 and determine A) what their speed was in the medium and B) what their speed was once they left it. If light reduces speed, but comes out on the other side with the same frequency it went in with, energy must have been conserved, so it must have been the wavelength that changed to accommodate the change in c. I wonder how a particle changes its wavelength? The greyhound bus example is interesting. We haven't actually gotten a greyhound bus up to around c yet, so we don't know what the refractive index of free space is at that wavelength(theoretically, the speed of light could not be a barrier at all to a greyhound bus), but my impression, from the behavior of energetic massive particles, is that n=1 at all frequencies in the normal vacuum of space. Other mediums may have frequency dependent refractive indexes, but the equations of special relativity would not work if the refractive index of normal empty space were not 1. But, that doesn't mean we can't change the refractive index of empty space.

Okay; I'm with you; but . . .

as to the first link, I don't get how they can claim that mass is spatial extent on anything more than a sub-atomic level. Consider two spheres of radius r. One is made of lead and the other styrofoam. Clearly the lead one has more mass, but it is exactly the same spatial extent as the styrofoam. So, the "reaction time" between particles is the same. I mean sure, that may work on an atomic level defining the mass, but then you have to ask why the mass of a macroscopic object is simply the sum of the masses of its constituent particles despite the large empty space between the atoms. One would have to claim that information and forces travel instantly across these gaps between the microscopic particles in order for the mass of the macroscopic object to be just the sum of the masses of the microscopic particles. This would, of course mean that such external forces traveling through macroscopic objects would travel faster than the speed of light(traveling the speed of light across the spatial extent of the atoms themselves and infinitely fast across the gaps between the atoms). There may be something to the idea as it does appear to work on a microscopic level, but the logical extension to macro-scopic particles (which they conveniently ignore) leads to results that are contradictory to our observed reality.

The physicist you mentioned in Atlanta has the same problem...expanding his idea to macroscopic objects is where it breaks down.

Keep in mind that scientists are forever terrified of getting a bad name by "going too far". Essentially, they can question up to 1.25 assumptions of the Standard Model, or accepted cosmology, but not question anywhere nearly 1.75 assumptions in one paper. But I suspect that many suspect assumptions come in pairs; and, anyways, that makes it difficult to find very imaginative theories, however plausible and sound they might be. Lots of self-censorship.


of course. I count myself among those. None of the things I write here would I ever publish is a real scientific journal. They are unproven ideas that would challenge much of conventional thinking....like the whole cosmology is bullshit thing. I completely agree. I can't believe they actually allow these guys to put "dark matter" in the air and space museum when there is absolutely no proof it actually exists except for a missing parameter in their equations that is need to make their equations work. It is fine to infer the existence of a thing based upon a missing parameter in an equation. But you don't go actually claiming the thing exists until you have proven that it does. These guys have committed a crime against the scientific method.

Doesn't the speed of light slow down a great deal in bose-einstein condensates?

Yeah. And I would argue that this is because you have increased the energy density by squeezing the particles so close together. Their waveforms are overlapping and there is all kinds of interference going on. I would argue that this is doing the exact opposite of what the idea I proposed before would do. The objective would be to eliminate all of the overlapping waves running back and forth and interfering with each other.
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Re: physics.cpp

Postby klauss » Sun Mar 28, 2010 7:41 pm

chuck_starchaser wrote:Another way of looking at it:
Imagine you were playing the 100-door game 100 times.
Each time:
  • you pick a door (with a 1% chance of being right)
  • then the host opens 98 doors
  • you stick to your initial choice
Now, do you really think you'll win about 50 games?
Because that's the absurd conclusion your 50-50 mental model leads to...

I see that.
But then what's the problem with my reasoning?
Perhaps I have to model the two choice steps... I was lazy and didn't want to (too many cases). Still... I don't see anything wrong with the way I modelled the problem (except that the result is wrong ;) ). I'll have to look hard.

chuck_starchaser wrote:It implies that the host's action of opening 98 doors somehow affects the chance of
the door you originally picked being the right door favorably. How would it do that?

Again... chances aren't immutable, they depend on uncertainty about something, and if you learn something new then uncertainty will change.

P(choose right) is the first probability (1%), the second is a conditional probability, P(choose right given that you know 98 doors are empty). That "new" probability can be different, by all means.

EDIT: to see how probabilities can change, think of this case: you choose one of 100 doors. Then you have 1% chance of being right, and the host opens the door you chose, and there it is, the prize. What's the chance of being right (if you were to choose that door again) now? It's the same choice, but with different probabilities of success, only because your knowledge of the world has changed.
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Re: physics.cpp

Postby chuck_starchaser » Sun Mar 28, 2010 9:30 pm

klauss wrote:
chuck_starchaser wrote:Another way of looking at it:
Imagine you were playing the 100-door game 100 times.
Each time:
  • you pick a door (with a 1% chance of being right)
  • then the host opens 98 doors
  • you stick to your initial choice
Now, do you really think you'll win about 50 games?
Because that's the absurd conclusion your 50-50 mental model leads to...

I see that.
But then what's the problem with my reasoning?
Perhaps I have to model the two choice steps... I was lazy and didn't want to (too many cases). Still... I don't see anything wrong with the way I modelled the problem (except that the result is wrong ;) ). I'll have to look hard.

chuck_starchaser wrote:It implies that the host's action of opening 98 doors somehow affects the chance of
the door you originally picked being the right door favorably. How would it do that?

Again... chances aren't immutable, they depend on uncertainty about something, and if you learn something new then uncertainty will change.
True. But does the the fact that the host leaves the door you picked closed mean anything about it?
Nope.
He leaves that door closed simply because he has to, because you picked it. Nothing more.
Whereas, the other door he leaves closed, he also HAS TO leave it closed, because it contains the prize.
This is how it works out 99% of the time, anyways.
It only changes when you picked the right door to begin with, and so he can leave any other door closed; but
this is rarely the case.

P(choose right) is the first probability (1%), the second is a conditional probability, P(choose right given that you know 98 doors are empty). That "new" probability can be different, by all means.

EDIT: to see how probabilities can change, think of this case: you choose one of 100 doors. Then you have 1% chance of being right, and the host opens the door you chose, and there it is, the prize. What's the chance of being right (if you were to choose that door again) now? It's the same choice, but with different probabilities of success, only because your knowledge of the world has changed.
True; but ditto.
After he opens 98 doors, the probabilities are 100% the prize is behind one of the two doors; but the probability
is NOT split 50-50. The reasons why those two doors are closed are very different, 99% of the time.
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