Off-topic posts about probability (from: ext. rules to 4d)

[Geosphere]

Whenever there is a 50% chance of something happening,

This case NEVER exists. Everything that happens will have a 100% chance of happening, we just have no way to determine it.

A coin flips. 50-50.

No. 50-50 to our limited information. BUT if we knew the weight and wear on the coin, the position on the finger, the speed and angle of the finger flick, the amount of moisture on the thumbnail, the relative humidity of the air, the arc and distance travelled of the elbow and forearm, how heavily the person is breathing and the windspeed, the pressure due to distance from sea level, the ... the ... the ... ad infinitum.

Once all variable are taken into account, there is nothing random and no way that the coin can fall in any matter except in the way it does.

"Random" only means "acted upon by more variables than commonly calculable". A die roll might be different if you had a hot shower in the morning rather than a cold shower, which changes the elasticity of the skin of your fingers, and therefor to us deemed "random". But there was only 1 possible outcome of that die roll - the one that occured under the myriad conditions imposed upon it.

[Keiji]

Yes, you have a good point there. It's so obvious in fact that I can't see why I didn't realize that when I read about Schrodinger's Cat (or however you spell that).

[PWrong]

I know that seems right, but it's not actually true at the subatomic level.

The uncertainty principle says that we can't measure anything with perfect accuracy. When you measure something, you're actually measuring photons or particles that bounce off it. These particles can change the the properties of the object you're trying to measure. This means it's impossible to know an objects position and velocity exactly.

You've probably seen the old model of the atom, that looks like a mini solar system- nucleus in the middle, electrons travelling exact orbits around it. This model has been out of date for about 50 years now. The atom is now drawn with hundreds of dots representing all the places an electron might be. You can't know for certain, but quantum physicists can calculate the various probabilities exactly.
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[Geosphere]

Pwrong, that kind of proves my point...

We can't calculate it exactly, that's 100% right.

That doesn't make it random. That makes it incalculable.

[PWrong]

BUT if we knew the weight and wear on the coin, the position on the finger, the speed and angle of the finger flick, the amount of moisture on the thumbnail, the relative humidity of the air, the arc and distance travelled of the elbow and forearm, how heavily the person is breathing and the windspeed, the pressure due to distance from sea level, the ... the ... the ... ad infinitum.

Once all variable are taken into account, there is nothing random and no way that the coin can fall in any matter except in the way it does.

"Random" only means "acted upon by more variables than commonly calculable".

What are some examples of these variables, when finding the position of a single particle in a vacuum with no outside forces acting on it?

[Geosphere]

Oh, things like the starting position and spin of a particle, where the reading of such information itself would alter it.

[elpenmaster]

if you flip a united states quarter many times, it will land heads up more often

but say you were flipping a two dimensional coin. there are three ways it can land: heads up, tails up, or on its side. since a 2 dimensional coinn has zero area on the edge, it would be impossible to land exactly on the edge. but if it did. . . it would be exactly 50-50 chance of falling to either side

[PWrong]

That's only two variables. How is that "more than commonly calculable?"

If you don't know where the particle is, you can't measure where it is, and you can't calculate where it is by measuring other factors, then the particle could be anywhere. Surely that's the same as being random.

[Geosphere]

Surely that's the same as being random.

No.

You are implying that your knowledge of it (or lack of it) determines where it is.

It only determines if you are right.

It is not random. it has 100% chance of being where it is at any moment. The fact that we don't know where does not change its location.

Its very Schroedinger.

[Geosphere]

it would be exactly 50-50 chance of falling to either side

No.

Again, what if I flip it with force that makes it spin exactly 7 complete rotations before landing on the ground where it will flip 180.

ALWAYS.

Then, what it the ground were rougher? The coin more worn.

It is NOT a 50-50 chance. There is a 100% chance of it landing the way that it will - no doubt. Just not a calculable chance.

[PWrong]

How do you explain quantum experiments that deliver a different result every time, even with exactly the same initial conditions, when we know there are no outside forces acting on the particle?

Also, what about quantum tunnelling, where an electron has a small but finite chance of doing something that should be impossible? For instance, lucky electrons can break the speed of light, or simply disappear and reappear on the other side of a strong energy barrier for no reason. Any attempt to dictate what a particle can and can't do results in failure.

[Geosphere]

You're talking in such definites, as if science has no limits.

If it can do something impossible, then it isn't. (On Miracles, David Hume)

We KNOW there are no outside forces on the particle?

I absolutely 100% cannot believe that we know everything about particles to say that. There are definitely forces we cannot perceive or conceive at this time.

Once upon a time, there was no such thing as germs...

[Euclid]

I absolutely 100% cannot believe that we know everything about particles to say that. There are definitely forces we cannot perceive or conceive at this time.

This ("forces we cannot perceive or conceive at this time") evokes the notion of other dimensions. A recent speculation is that gravitons come and go. Where do they go? The thought is into another dimension that we cannot access (yet!). An experiment to test this conjecture is waiting on the completion of the hadron supercollider.

So, when the Sphere rose up out of Flatland it disappeared to A Square's perception--off into the 3rd dimension.

Here's some speculation: if gravitons are the particle that produce gravity and they shuttle between 3-space and 4, could we build a machine to shuffle large quantities of them out of this dimension such that gravity would weaken in the delpletion area?

[Geosphere]

This ("forces we cannot perceive or conceive at this time") evokes the notion of other dimensions.

No.

This evokes the lack of theoretical and technological knowledge needed.

The moment we believe we know all there is to know is the moment we stop evolving.

Once upon a time, unexplained phenomena was "Magic". Now "Extradimensional".

Bull.

Unexplained phenomena is simply unexplained. Yet.

Show a flashlight to a barbarian and it is magic. He cannot conceive of a battery, let alone a bulb. Just because he doens't know of it does not mean it is impossible. Merely impossible for his knowledge to grasp.

[PWrong]

If it can do something impossible, then it isn't. (On Miracles, David Hume)

I didn't mean actually impossible. I meant impossible under classical, non-quantum theory.

I absolutely 100% cannot believe that we know everything about particles to say that. There are definitely forces we cannot perceive or conceive at this time.

If you don't believe in the random stuff, you're in good company. "God does not play dice"-Einstein.

I don't particularly like the idea either, but it's been around for nearly 50 years now and there's a lot of evidence to suggest that there's no pattern to the results of experiments.

I'm not saying that we can't predict anything. Apparently we can predict that the probability of something is exactly something percent, to as many decimal places as we want.

It might be the result of phenomena we can't explain yet, but how do you know that randomness is impossible? Maybe we just can't comprehend an universe that is inherently random.

[Euclid]

This ("forces we cannot perceive or conceive at this time") evokes the notion of other dimensions.

No.

Yes, browse: http://www.iop.org/EJ/abstract/1126-6708/2002/12/039

Exploring Small Extra Dimensions at the Large Hadron Collider

[pat]

I don't particularly like the idea either, but it's been around for nearly 50 years now and there's a lot of evidence to suggest that there's no pattern to the results of experiments.

It's worse than just there's no pattern. Look up Aspect's experiment and Bell's Inequalities. Aspect's experiment indicates that the laws of quantum mechanics are incompatible with any local, hidden variables.

[Geosphere]

This ("forces we cannot perceive or conceive at this time") evokes the notion of other dimensions.

No.

Yes, browse: http://www.iop.org/EJ/abstract/1126-6708/2002/12/039

Exploring Small Extra Dimensions at the Large Hadron Collider

No, I'm talking about other things that are what we consider uncontrollable and unknown forces.

[Euclid]

No, I'm talking about other things that are what we consider uncontrollable and unknown forces.

I guess I am at a disadvantage here. What do you mean by "uncontrollable and unknown forces":?:

[Geosphere]

If I knew that, I would know and be in control, wouldn't I... :wink:

[Euclid]

If I knew that, I would know and be in control, wouldn't I... :wink:

Thank you. For a momemnt there I thought I was at a disadvantage.

[elpenmaster]

hey geosphere

about the 2-d coin and the 50-50 flip

if you had a 2d coin in 3d and flipped it and it came down and landed on its side, it would have a 50-50 chance of falling either way

*trick question* :twisted:

however, there is a zero chance that the coin will land on its edge, because the 2d coin would have no edge area, and thus would have a zero probability of landing on it

so, the 2d coin that landed on its edge would have the 50-50 chance of falling to either side

*HOWEVER*

the coin would have a zero chance of landing on its edge in the first place

so yes the coin could never have a chance to do the "50-50 flip" :wink:

[Geosphere]

Why in the world would the coin have no edge area? If it's a rectangle in a 11x2 ratio, there's certainly an edge.

And what if there's 2D dust/wind/tremors.

50-50 suddenly becomes something different.

[PWrong]

He's talking about a 2D coin in a 3D universe. It has no width. It doesn't really apply to probability though, and it wouldn't have a 50% chance anyway, as you said. It's easy to show that there is no real chance involved with fipping a coin. But it's not so easy to do with particles in a vacuum. I don't think it's a good idea to invent extra hidden forces to explain patterns in data, when those patterns don't exist anyway.

I didn't quite understand what that article is saying. Are they saying that they actually found the small extra dimensions, or just that it's possible to find them? The article was sent in November 2002, so they must have had some results by now.

Clearly, the effects described in that article are "unknown and uncontrollable". If there is another variable affecting the randomness in quantum mechanics, it's probably the extra dimensions.

[RQ]

Geosphere, just because it happened doesnt mean it had a 100% chance of happening, simple as that.
Scientists maybe pursuing a GUT or TOE, in hope that GOD does not play dice.

[Geosphere]

Geosphere, just because it happened doesnt mean it had a 100% chance of happening

Oh really?

I find that response 100% impossible.

[PWrong]

Maybe there's a 100% probability that God does play dice.
Most candidates for the TOE have an element of chance in them. As long as it can predict all probabilities exactly, it still counts as a consistant theory. I admit it would be nicer to have one without any chance at all, but we have to accept the universe as it is.

[Geosphere]

Is it chance or merely our inability to perceive what effects the outcome?