Does probability come from quantum physics?

February 5, 2013, UC Davis

(Phys.org)—Ever since Austrian scientist Erwin Schrodinger put his unfortunate cat in a box, his fellow physicists have been using something called quantum theory to explain and understand the nature of waves and particles.

But a new paper by physics professor Andreas Albrecht and graduate student Dan Phillips at the University of California, Davis, makes the case that these actually are responsible for the of all actions, with far-reaching implications for theories of the universe.

Quantum theory is a branch of that strives to understand and predict the properties and behavior of atoms and particles. Without it, we would not be able to build transistors and computers, for example. One aspect of the theory is that the precise properties of a particle are not determined until you observe them and "collapse the wave function" in physics parlance.

Schrodinger's famous thought experiment extends this idea to our scale. A cat is trapped in a box with a vial of poison that is released when a radioactive atom randomly decays. You cannot tell if the cat is alive or dead without opening the box. Schrodinger argued that until you open the box and look inside, the cat is neither alive nor dead but in an indeterminate state.

For many people, that is a tough concept to accept. But Albrecht says that, as a , he concluded some years ago that this is how probability works at all scales, although until recently, he did not see it as something with a crucial impact on research. That changed with a 2009 paper by Don Page at the University of Alberta, Canada.

"I realized that how we think about quantum fluctuations and probability affects how we think about our theories of the universe," said Albrecht, a theoretical cosmologist.

One of the consequences of quantum fluctuations is that every collapsing spits out different realities: one where the cat lives and one where it dies, for example. Reality as we experience it picks its way through this near-infinity of possible alternatives. Multiple universes could be embedded in a vast "multiverse" like so many pockets on a pool table.

There are basically two ways theorists have tried to approach the problem of adapting to the "real world," Albrecht said: You can accept it and the reality of many worlds or multiple universes, or you can assume that there is something wrong or missing from the theory.

Albrecht falls firmly in the first camp.

"Our theories of cosmology say that quantum physics works across the universe," he said. For example, quantum fluctuations in the early universe explain why galaxies form as they did—a prediction that can be confirmed with direct observations.

The problem with multiple universes, Albrecht said, is that it if there are a huge number of different pocket universes, it becomes very hard to get simple answers to questions from quantum physics, such as the mass of a neutrino, an electrically neutral subatomic particle.

"Don Page showed that the quantum rules of probability simply cannot answer key questions in a large multiverse where we are not sure in which pocket universe we actually reside," Albrecht said.

One answer to this problem has been to add a new ingredient to the theory: a set of numbers that tells us the probability that we are in each pocket universe. This information can be combined with the quantum theory, and you can get your math (and your calculation of the mass of a neutrino) back on track.

Not so fast, say Albrecht and Phillips. While the probabilities assigned to each pocket universe may seem like just more of the usual thing, they are in fact a radical departure from everyday uses of probabilities because, unlike any other application of probability, these have already been shown to have no basis in the quantum theory.

"If all probability is really , then it can't be done," Albrecht said. "Pocket universes are much, much more of a departure from current theory than people had assumed."

The paper is currently posted on the ArXiv.org preprint server and submitted for publication and has already stimulated considerable discussion, Albrecht said.

"It forces us to think about the different kinds of probability, which often get confused, and perhaps can help draw a line between them," he said.

Explore further: Physicists Calculate Number of Parallel Universes

More information: albrecht.ucdavis.edu/

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EyeNStein
1.9 / 5 (18) Feb 05, 2013
The whole point of the schroedinger cat experiment is the absurdity of extrapolating from quantum to macro or even universe scales. The cat knows if its alive, even if we only know a probability figure for its demise. An autopsy would clearly show when the cat died, not when it entered some superimposed state.
Tektrix
3.4 / 5 (5) Feb 05, 2013
The paper is pretty neat. An example of what is being talked about here is coin flipping. How can the probability of the outcome of a coin flip be traced back to quantum mechanical uncertainty?

As it turns out, it all starts with water and polypeptides in your nervous system. Quantum uncertainty at that level introduces enough probability in molecular transport to evoke less-than-perfect physical prowess, which ultimately leads imprecise control of the energy required to repeatedly produce a perfect flip and snatch.
ValeriaT
1.2 / 5 (18) Feb 05, 2013
Quantum computing is neither faster, neither more secure than the classical computing (but it's still good grant and salary generator for physicists, who manage to pretend the opposite): Why quantum computing is hard - and quantum cryptography is not provably secure, No quantum trick – no matter how complex or exotic – can improve the capacity of quantum optical communication
ValeriaT
1.7 / 5 (12) Feb 05, 2013
BTW The article title "does probability come from quantum physics" is logically orthogonal to the preprint abstract "..we claim there is no physically verified fully classical theory of probability..".
Whydening Gyre
1.4 / 5 (11) Feb 05, 2013
"God does not play with Dice." - Albert Einstein.
He has, however, found a coin or two to flip...
kochevnik
2 / 5 (8) Feb 05, 2013
@EyeNStein The cat
There are at least two cats. Your feeble attempt to square QM with classical physics employing a hidden English predication failed
Just another non-falsifiable speculation.
You're wrong. Perhaps SOME experiments are beyond present abilities, but others are doable by brighter minds than you
EyeNStein
1.4 / 5 (9) Feb 05, 2013
two cats.
The invention of a second non-verifiable cat doesn't add to our understanding of the universe it only adds confusion. If you had mentioned that micro scale vibrators can be simultaneously vibrating and not: I would have agreed. But concious cats and the cyanide release sensors constitute a measurement-improbability collapses-clasical reality appears. No second cat is required.
axemaster
4.5 / 5 (15) Feb 05, 2013
You can accept it and the reality of many worlds or multiple universes, or you can assume that there is something wrong or missing from the theory.

WOW! What a ridiculous statement! Many, many physicists accept the veracity of quantum theory but reject the idea of multiple universes. Multiple universe are NOT required by the theory, and are completely speculative! Whether or not other universes exist is a matter of philosophical OPINION. Moreover, the issue is unscientific in nature, since there's not even any way to test it!

You'd expect to hear this sort of thing on TV and among the general public, but from a physicist! Unbelievable!
ValeriaT
1.6 / 5 (14) Feb 05, 2013
Whether or not other universes exist is a matter of philosophical OPINION
Well, not quite. For me it's mostly a question of physically and logically rigorous definition of multiverse.
kochevnik
1.9 / 5 (9) Feb 05, 2013
Whether or not other universes exist is a matter of philosophical OPINION.
So is the question of existence itself. Existence is completely dependent upon what David Bohm described as "implicit order," which is only peripherally understood
vacuum-mechanics
1.3 / 5 (16) Feb 05, 2013
One of the consequences of quantum fluctuations is that every collapsing wave function…..

It is interesting to note that up to now we still could not understand 'wave function of what, or what is wavy? Conventionally, it is just a mathematical abstraction; this is one real problem in quantum mechanics. Understanding the mechanism of quantum mechanics as below, could answer the problem.
http://www.vacuum...19〈=en
Tektrix
3.9 / 5 (11) Feb 05, 2013
Quantum computing is neither faster, neither more secure than the classical computing . . .


Unfortunately, this article is about probability and its origins, not quantum computing.

zorg
1 / 5 (2) Feb 05, 2013
Studies reported on this site have shown that "collapse" of a wave function is an "overshadowing" by another wave function and that the overshadowed function(s)still exist. In addition, the "observer" is not the research staff but a hidden, ordering "field."
TheGhostofOtto1923
1.6 / 5 (13) Feb 05, 2013
The whole point of the schroedinger cat experiment is the absurdity of extrapolating from quantum to macro or even universe scales. The cat knows if its alive, even if we only know a probability figure for its demise. An autopsy would clearly show when the cat died, not when it entered some superimposed state.
Cat knowing, forensics, the ASPCA, and T gondii are some of the many parameters not included in the thought experiment.
tigger
3.4 / 5 (14) Feb 05, 2013
The human sensors are a magical waveform collapsing mechanism... um... no.

The observer is as part of the system as anything else... there IS NO OBSERVER.

Yes, think about it... the human eye looking at something to observe is no different than photons interacting with a rock.

Interacting with matter... be it a rock, a magnetic field, a human eye... they are all the same, they all change the properties of the thing they are interacting with.

Why the continual, somewhat arrogant, fixation that the human body is a magical device that collapses waveforms into a reality? Is this because you think there is a 'soul'... some part of the human body that is outside the bounds of physics?

Eikka
2.3 / 5 (9) Feb 05, 2013
The cat knows if its alive, even if we only know a probability figure for its demise. An autopsy would clearly show when the cat died, not when it entered some superimposed state.


Collapsing the wavefunction also decides when the cat died.

Consider that at the moment of observation the cat exists in all possible states it can take while it is in the box, which includes all the possible histories, and all possible times of death.

The laws of quantum mechanism apply equally to what and where and when. The isotope that relases the poison by decaying is not in superposition only for decaying or not decaying, but when it decays if it does.

The cat knowing that it is alive is irrelevant, because nobody outside the box can read its mind telepathically.
Zackc
1 / 5 (8) Feb 05, 2013
One crucial factor missed out is the human mind, not measurable and yet it could be the main factor responsible for materializing which probability or pocket of universes it desires. At one time, the earth was flat, but now the mind now "knows" that the earth is actually a ball in space.
brodix
1 / 5 (5) Feb 05, 2013
One other explanation for probability is that the lightcone of any event is not complete prior to the event, so there is no way to verify total input prior to an event. The laws may be deterministic, but input is not.
As for multiworlds, it is a question of whether we view time as a vector from a determined past into a probabilistic future, or the changing configuration of what is, that turns future probability into actuality. Consider this image; http://en.wikiped...film.svg
Do we view it as the present moving from left to right, or the frames moving right to left?
Before a race, there are many possible winners, but after it, only one.
StarGazer2011
1.5 / 5 (8) Feb 06, 2013
seems it at least partially depends on if you consider that the cat is in BOTH states or in NEITHER state, if its in NEITHER then there is no requirement for multiverse obviously.
But this whole 'collapsing the waveform' or 'quantum uncertainty' seems to be mistaking ignorance for epiphany to me.
Ugh, if a phenomena requires an observer to be in a collapsed state, how did dinosaurs exist, or perhaps they didnt? Copenhagen taken to its extreme form seems to be sort of creationism to me, with the implicit assumption that before humans there was some sort of 'universal observer'.
VendicarE
3.2 / 5 (5) Feb 06, 2013
The state of the cat is entirely irrelevant to the issue of probability.

The probability that the cat is dead or alive is identical - by the design of the experiment - as the probability that the radioactive source decays.

The state of the cat is only a macroscopic indicator of that decay.

The problem with the question of course, is not having a precise definition of probability that is devoid from connection with the real world.

The words "choice" or "selection" are part of the definition of probability and therefore make the definition dependent upon physical existence.

There can be no choice or selection without physical existence.

On the other hand defining probability without any physical connection seems to leave the definition simply a matter of creating a weighted set, and comparing the weight of one element with the weight of the set.

This certainly has no connection to quantum mechanics.

theon
1 / 5 (5) Feb 06, 2013
The only hope to reach a convincing interpretations of quantum mechanics is by modelling the dynamics of measurements. This has been done in a rich enough model, which clarifies the cat issue: the cat dies because of its interaction with the apparatus. This approach leads to a minimal interpretation: the statistical interpretation, about which Einstein wrote even in his last year. Trying to solve our problems with QM in other universes, as the authors do, is a non-minimal approach; it can and should be neglected.
Eikka
2.5 / 5 (13) Feb 06, 2013
Copenhagen taken to its extreme form seems to be sort of creationism to me, with the implicit assumption that before humans there was some sort of 'universal observer'.


The problem many people seem to be having with QM is that they interpret the word "observer" to mean a literal concious and cognitive observer.

What the word in QM means is simply the interchange of information. The superposition can only be in all states if no other thing depends on it being in a certain state. The classical world arises from these dependencies where A depends on B depends on C depends on... where each limits the possible states of the other according to the rules of physics until you're left with no wiggle room for the wavefunctions.

For that purpose, a rock can be the observer, and that is also the reason why Shrödingers cat has to be in a box so nothing else can interact with it until the box is opened. Quantum systems only behave in "weird" ways when you isolate them.

vlaaing peerd
2 / 5 (1) Feb 06, 2013
I don't think flipping a coin on macro scale has anything to do with probability or in the least so little it has no influence on the outcome.

When you are able to count in all influencing factors one should be able to exactly predict the outcome of the flipping coin. Probably (no pun intended) the bigger the scale the less likely quantum scale probability would have influence on it.
rkolter
5 / 5 (3) Feb 06, 2013
The whole point of the schroedinger cat experiment is the absurdity of extrapolating from quantum to macro or even universe scales.

I didn't see anyone really give you a full response. The whole point of the schroedinger cat is not to point out the absurdity of scaling up quantum effects to macro-scale objects. It is to provide a reference that is based in reality that surrounds us. For a LOT of people, it is far easier to understand "the cat is in an undetermined state" than it is to understand any explanation using waves and particles. The cat "experiment" was never meant to be taken seriously. When I explain it, I always end it with, "But in this case we know the cat is DEAD. Nobody poked air holes in the box..." You'd be surprised how often someone says, "Yeah if they poked air holes in we could see the cat..." And ta-da, a light goes off. :)
antialias_physorg
3 / 5 (6) Feb 06, 2013
For an intersting thought experiment on how the conscious observer is (or isn't) a crucial part of QM one may take a look at the "Wiegner's friend" extension of the Schrödinger's cat experiment.

http://en.wikiped...s_friend

A rather more dramatic form can be achieved by placing a conscious observer (again Wiegner's friend) inside the box.
rkolter
5 / 5 (2) Feb 06, 2013
I do not believe in QT. First of all "random" does not exist. Period. We know there is some forces determining the result of an event. We just don't know what they all are, and we don't understand how they work entirely. If we did have complete understanding of any given system, we would be able to 100% predict any behavior.


I don't know how you can say with certainty that randomness does not exist when you openly admit we do not know everything there is to know about physics. Simply put, what if the laws of physics include randomness? We have plenty of evidence of random events occuring. It seems more likely that random behaviour DOES exist, and we simply don't know why it exists. That question would then fall into a huge category of very interesting unknowns we can confirm, but do not fully understand yet.
antialias_physorg
3.9 / 5 (11) Feb 06, 2013
I know because you cannot show me a single event in nature that is random.

Radioactive decay would be one (of many) examples.
While you can fit curves to random processes (distributions) you cannot predict when an individual event will occur. Randomness is constrained - but it can be shown that it cannot be the result of smaller, fully deterministic processes. (such smaller processes would constitute 'hidden variables').

And by the Bell tests we have a strong argument that hidden variables do not exist. You could only save that with non-local hidden variables as in the deBrogli-Bohm interpretation of QM. But that opens up an entirely different box of problems.

And there is a strong indication that complete determinism isn't in the cards. (e.g. if you do double slit experiments with single electrons in the apparatus you still get interference patterns)
Valentiinro
3.3 / 5 (7) Feb 06, 2013
"Radioactive decay would be one (of many) examples."
I already dealth with this specific arguement in my previous post. If radioactive decay is random, then how is it the most precise event we can use to determine the passage of time with.
If we can predict exactly how long it will take to happen, than how can it possibly be a random event? There is a very specific set of rules governing radioactive decay. We simply do not understand. I tell you again. Your quantum theory is "witchcraft" and very very unscientific.


You don't know how an atomic clock works.

http://en.wikiped...ic_clock

It has nothing to do with radioactive decay, which is random.
antialias_physorg
3.8 / 5 (10) Feb 06, 2013
If radioactive decay is random, then how is it the most precise event we can use to determine the passage of time with.

Over many decay events you can average out - that's how we can use decay for measuring time (if there were few events then the dating via radiooactivity wouldn't work nearly as well).

It's like flipping a coin - you can't predict any one specific outcome, but over a million coin tosses you can map all the possible paths and see that the paths that lead to a near 50/50 split are VASTLY in the majority over those that are all heads - so betting on teh average outcome is better than betting on the extreme one.

I think you need to look up the difference between a probabilistic event and a probability distribution.
ValeriaT
1.6 / 5 (13) Feb 06, 2013
First of all "random" does not exist. Period.
I don't think so. Sometimes the information is simply lost. For example, the surface of water droplet cannot reflect the movements of all water molecules which are bouncing and colliding inside of it. Some of these movements are simply lost for the observer from outside for ever. How we can be sure, that the randomness of quantum mechanics doesn't work in the similar way?
Royale
1 / 5 (1) Feb 06, 2013
The paper is pretty neat. An example of what is being talked about here is coin flipping. How can the probability of the outcome of a coin flip be traced back to quantum mechanical uncertainty?

As it turns out, it all starts with water and polypeptides in your nervous system. Quantum uncertainty at that level introduces enough probability in molecular transport to evoke less-than-perfect physical prowess, which ultimately leads imprecise control of the energy required to repeatedly produce a perfect flip and snatch.


I just have to say Tektrix, that this almost a goddamn PERFECT comment. I've reused it (with a reference) on Facebook, and about to add it to Google .
SethD
1.7 / 5 (12) Feb 06, 2013
Nothing comes from nothing.
Disproselyte
1.5 / 5 (8) Feb 06, 2013
Not only randomness is an evident essential aspect of QM, claiming determinism as a universal fact to predict everything is not serious today: already deterministic gravitationally bound systems exceeding 3 bodies have been shown for more than a century to totally lose determinable properties beyond a time dependant predictability horizon. Beyond that horizon, only probalilistic approaches allow to do statisical predictions for those chaotic systems ruled by resonance. Determinism, although very useful, is only a practical simplification, just as linearity and so on, applicable in some limited artificial cases, which are idealising reality, which is evidently independant of us humans. It is our perception and interpretation to understanding, which is totally subjective.
BTW, the theory of scale relativity still gives the most elegant interpretation, but this is another sensitive argument.
antialias_physorg
4 / 5 (8) Feb 06, 2013
Control every variable down to the quantum level and you can make the coin land the same way every time.

Since you can't control it to the quantum level that's a nonsensical approach. At the quantum level values aren't discrete but a probability distribution.
ValeriaT
1 / 5 (10) Feb 06, 2013
The problem with multiple universes, Albrecht said, is that it if there are a huge number of different pocket universes
This article got into exactly the opposite conclusion. In this article The Multiverse Created Probability To Explain The Multiverse (synopsis)
Whydening Gyre
1 / 5 (11) Feb 06, 2013
Does probability come from quantum physics?

I would say -
Probably...
Whydening Gyre
1.4 / 5 (11) Feb 06, 2013
One crucial factor missed out is the human mind, not measurable and yet it could be the main factor responsible for materializing which probability or pocket of universes it desires. At one time, the earth was flat, but now the mind now "knows" that the earth is actually a ball in space.

Humans knew that LONG before they thought it was flat...
VendicarE
3.7 / 5 (3) Feb 06, 2013
Your faith is not supported by experiment.

"We could determine the exact moment of the cats death. Unwitnessed." - Jalmy
VendicarE
4.2 / 5 (5) Feb 06, 2013
You are confusing random with unpredictable.

A coin toss can produce completely random results, and yet the statistical character of those tosses are absolutely predictable.

"The fact that these rates are measurable and can be generalized with a formula tells you that they are not random." - Jalmy

If Statistics wasn't predictable, then it would have no value.

Since it does, it is.

Since it is, you are wrong.
EyeNStein
1.4 / 5 (9) Feb 07, 2013
"The cat knowing its alive" is not irrelevant. The cat would be very aware of being locked in a confined space. Its only human vanity that is prepared to create whole universes rather than admit the obvious classical nature of a cat collapsing its own wave function even if it is not fully sentient.
daywalk3r
3.1 / 5 (14) Feb 07, 2013
At the quantum level values aren't discrete but a probability distribution.

In the scope of CI QM, yes.

But what about out of it? What if QM does not = reality? Is it still all "random"? Because you said so? Because the Copenhagenists said so? Or just because the sky is blue?

What makes you so certain (that nothing is certain)? Isn't that allready a flawed logic construct to begin with?

The Bell experiments? There were no loophole-free Bell tests done yet. Double-slit? Without a truckload of fundamental assumptions, essentially inconclusive.. What else?

Nuclear decay? As random as a humans lifespan. While the average might converge to a certain value, it doesn't strictly dictate the path of an individual (which cannot be predicted without fully understanding the underlying principles and having sufficient data).

...

At this point, the only reasonable and honest conclusion that can be drawn is, that we can NOT be certain of either..

Ergo, WE SIMPLY DO NOT KNOW (yet).
rkolter
3.9 / 5 (7) Feb 07, 2013
Something being predictable at any lvl means it is not random. If there is a patern to it then it isn't "random" that's the whole point.


Your whole point is wrong, then.

You can measure the probability of something happening with great accuracy. That does not mean that an individual event of that class is not random.

Since you say half-life is not random, consider carefully what half-life means. For a given sample of element X, 50% of the atoms in that sample will decay within the half-life. So if element X has a half-life of 10 minutes, some atoms will decay in 1 second. Some in 2 minutes. Some in 9 minutes and four seconds. Some in 15 minutes. Some in an hour...

You can say with great certainty that the half-life is 10 minutes. You can not say with any certainty when exactly a single atom (a single event) will decay. This is not because there are hidden variables we do not know about. It is because the decay is random.
daywalk3r
2.8 / 5 (11) Feb 07, 2013
IF you had the ability to measure the orbit of the electron around a the nucleus of Hydrogen atom you could apply a vector coordinate to every position it occupies. These would be discrete coordinates, not probabilistic ones.

I'm affraid it might be a bit more complicated..

There is no such thing as an absolute discrete coordinate either, as that would also require an absolute discrete point in time. And in the light of last several years of data, Planck time doesn't seem to fit that bill.

Everything is in constant motion, so every "discrete" coordinate is in essence just an average over a chosen time interval. No matter how sensitive/precise the measurements are, it will allways be like that. Sort of like the HUP in praxis.

In a certain sense, one could almost say that there is no such thing as a tangible NOW - just past, and future..

This actually makes all the arguments about discrete or probabilistic reality quite moot, as the ultimate answer seems to be neither, nor.
Whydening Gyre
1.4 / 5 (11) Feb 07, 2013
You are confusing random with unpredictable.

A coin toss can produce completely random results, and yet the statistical character of those tosses are absolutely predictable.
Aren't statistics and probability flip sides of the same coin?
"The fact that these rates are measurable and can be generalized with a formula tells you that they are not random." - Jalmy

If Statistics wasn't predictable, then it would have no value.

Since it does, it is.

Since it is, you are wrong.

Aren't statistics and probability flip sides of the same coin?
rkolter
4.2 / 5 (5) Feb 07, 2013
...The important part of it is that the probability amounts of each element is different and repeatable... If it was truely random. All elements would have the same probability of decay...

1 a: lacking a definite plan, purpose, or pattern

See the word pattern is key.


I removed your personal attacks and snide comments to try to pull the core of your argument out of your rant.

At the core of your arguement is the assumption that "no pattern" means necessarily "no solution is more likely than any other". This is not the case. It is perfectly reasonable to have a process that is random, with some options more or less likely.

Also, you excluded the second definition from Webster:

(2) Relating to, having, or being elements or events with definite probability of occurrence

This is what we've been talking about.
Tektrix
2.1 / 5 (7) Feb 07, 2013
I don't think flipping a coin on macro scale has anything to do with probability or in the least so little it has no influence on the outcome.


Regardless of what you think, the authors of the article use this very example to illustrate the premise. And AP'org is right- the intrinsic nature of QM makes the levels of control you are suggesting, impossible. The idea that perfect knowledge lends perfect control is centuries old and has been firmly refuted by the huge body of work in QM.
thrak
1 / 5 (3) Feb 07, 2013
LarryD...your comment about a "biocentric" view is well received. I tend to believe that anything, both matter and wave can be considered an observer...anything that can interact Consciousness is not required. The cat is either dead or alive, not both. A silly take on this would be, at what point in the classical sense of this mind experiment is the cat actually dead? Or is it alive? Is it when the first photon enters the observer's eye and an image of the cat forms? Is it when the observer examines the cat at rest to see if it is alive? Is it when the vet declares the poor beast deceased or in good health? I know it's silly, but my point is, existence is observation to some extent, perhaps entirely. The cat is observed by virtue of the fact that it exists. Obviously, such a claim has far reaching implications and really isn't done any justice in my flip response.
Q-Star
3.2 / 5 (13) Feb 07, 2013
Aren't statistics and probability flip sides of the same coin?


Yes, as long as you keep in mind that "statistics" only deals with things that have happened,,,, useful assessing causality.

Probability is the assessment of what might happen, once IT happens, it's no longer a probably event, it is an actual event with 100% probability (it happened.)

It is an important distinction.
antialias_physorg
3.5 / 5 (8) Feb 07, 2013
when talking about computers generating random numbers.

That's why no one talks about computer generating random numbers but only about computers generating pseudo-random numbers.
They are numbers that are generated via an algorithm (and hence absolutely predictable since the next number depends on the previous one).

The difference with truly random events in real life is that they aren't dependent on each other (and again there are tests that can be used to distinguish whether events are indpenedent or not)
Whydening Gyre
1.4 / 5 (11) Feb 07, 2013
Probability comes from the language used.{/q]
SOrry, Tau. gotta disagree with ya there - probability was here first...:)

Lite never comments. No probability there. lol


And I'm waiting for the day he/she/it does not 1 every comment I make. I'll have to go out and by a lottery ticket if THAT ever happens.
daywalk3r
3.2 / 5 (14) Feb 08, 2013
Probability comes from the language used. Lite never comments. No probability there. lol

Lite is a bot.

It has a blacklist of usernames, and continuously scours ALL articles in a predefined time interval. If it finds a comment by a blacklisted user, it automatically rates it with an assigned value (mostly 1).

As the bot is running on a server/computer, which runs off the electricity grid, and is connected to the internet through a multitude of devices (etc.), a fair bit of probability to its function still applies..

The admins who (should) manage this site seemingly don't give a damn about the comments sections, which in turn often gets pestered by spam, etc. So the next best thing in case the admins don't give a f***, is to give a s***.

Yea, I know, very on topic.. NOT! But who cares, eh? :-)
Whydening Gyre
1.4 / 5 (11) Feb 08, 2013
That might be right except for a couple small quirks. I've noticed lite does not rate certain users or if it does, it rates them a 5.
Interesting coincidence, that...
If I didn't know better, I'd say it's my very competitive wife. However, she has to ask me how to use Word, so...
daywalk3r
3 / 5 (12) Feb 08, 2013
Daywalk - I'll add the words "in a specific inertial reference frame" to what I said regarding the vector coodinates.

Doesn't matter. There is no such thing as 'perfect vacuum', neither is it possible to perfectly isolate any volume from the 'outside world' - no matter what you do, it will allways remain part of the whole/system.

Even passing an event horizon can not be strictly considered a causal disconnect (as often believed). What falls inside a BH does not dissapear, it becomes a contributing part of a bigger whole, which still affects the 'outside', be it either by gravity, resulting magnetic field(s), etc..

The only way how to achieve such 'disconnect' (on paper) is to define a threshold bellow which everything is considered negligible, or essentially non-existent. Well hello, I present to thee the magnifficient theory of QM..

When it comes to motion (or 'change') in a fundamental context, it can neither be considered absolutely discrete, nor truely random.
alaberdy
1 / 5 (1) Feb 08, 2013
@ValeriaT - Quantum computers would not be faster regular ones when calculating something like 3x5 or 2 4. However when calculating probabilities it clearly should be much much faster regular computers (when it would start working at all). And grants would be one of the ways to speed up that development.
Moebius
1 / 5 (6) Feb 08, 2013
The answer is the theory is wrong or God DOES throw dice.
EyeNStein
1.4 / 5 (9) Feb 09, 2013
I'm not even convinced that the single radioactive atom which is imperiling Schroedingers cat is in a superposition state. Its more similar to a point on the screen of the two slits experiment. That point is either illuminated or not by impact of a single photon. The only superposition in that experiment exists while the photon is in flight through both of the slits simultaneously. The scattering of dots on the screen is a classical probability distribution not a superimposed fuzzy pattern. A geiger counter never registers half a count, even when sealed in a box with a cat. A 'classical' autopsy still reveals when the cat died once the box is observed.
antialias_physorg
2.6 / 5 (5) Feb 09, 2013
The scattering of dots on the screen is a classical probability distribution

No it is not. If it were you'd see as a result the combined results of the same experiment done twice, but with one slit occluded each time.

But instead you see an interference pattern.
EyeNStein
1.4 / 5 (9) Feb 10, 2013
antialias_physorg: You misunderstand me. I'm just saying that the photon dots are either there or not: Rather than the photons which travel through both slits and are superimposed in flight. The dots distribution follows a classical calculatable wave interference, but like decaying atoms you never know where the next one will be till it has happened.
ValeriaT
1 / 5 (7) Feb 10, 2013
The existence of photons dots on the target screen is clear tangible evidence, that these photons do behave like the localized particles. The wave-interference-like distribution of photons indicates, these photons are surrounded with wave, which affects their path. Because photons itself do behave like the particles (and they're usually much smaller, than the slit itself), it's evident, that the wave behavior of photons doesn't come from photons itself, but from vacuum which surrounds them.
It's a simple clean logics, which is inaccessible for people, who are using the complex math. It's simply another hidden layer of reality for them. But the physicists and high-school teachers don't want you to use such a clean transparent logics, because they would lose their informational monopoly and social influence, if not job. Most of people want to understand the things as cleanly as possible and they resort to complex formal description of reality only when they don't see any other option.
ValeriaT
1.4 / 5 (10) Feb 10, 2013
I admit, for fooled sheep who are downvoting me obstinately is difficult to admit, they're fooled sheep - but this is simply, how the reality currently is. This is the power of new ideas, the power of new vision of reality. The problem with its understanding isn't in complexity of math involved - it is in your head and your prejudices only - as it always was. The situation well known from medieval times just repeats again. You didn't expect, you may appear in the position of hypocritical reactionary and ignorant opponents of Galielo or Pasteur?

Well, it just happens now. The world is changing - but the thinking of average people remains.
rkilburn81
2 / 5 (4) Feb 10, 2013
Not a theory, just a "what if" idea I have been contemplating...

When we look out at all the galaxies, we are actually looking out past the boundry of our universe, like inside a marble looking out and space time bends in on itself, and so we are looking out at every possible Universe, every possible shape and fluctuation the big bang could have taken since the begining of time? Like waves of photons interacting, these island universes can also interact within the greater multiverse.

This might explain a lot.. Thoughts?
GPhillip
not rated yet Feb 12, 2013
Well, here's a clue. The "observer" is only a simplification for what is really happening. In reality, the waveform is colapsed by decoherence from interaction with the environment. So, if my pet yellow dog is trained to bark at a live cat, and he doesn't bark when the box is opened, he becomes the observer and by hearing his bark or lack of it, I transfer that information to the environment and colapse the waveform. If however, I am out to pick up the paper and not there to hear the bark or lack of it, the cat is still in an undetermined state, with equal probability of being both alive and dead. Yes, you can perform a necropsy (on an animal, not an autopsy) and determine if the cat died earlier. This is simular to quantum erasure. It doesn't change the outcome of the thought experiment. Of course, that trick is easily demonstrated with electrons and the right setup of slits and detectors. This stuff really isn't that hard. Really, it isn't.
GPhillip
not rated yet Feb 12, 2013
Some may have missed my point. The outcome of the thought experiment doesn't depend on a human observer, or a dog or an insect. It only depends on the colapse of the probability wave by decoherence through interaction with the surrounding environment. Of course, if the outcome of the experiment has absolutely no interaction with the surrounding environment, none whatsoever, then the wave has not colapsed and the cat lives forever in an indeterminate state. More likely though, the cat would start to smell, the smell would attract flies, and so on until the interaction with the environment was great enough to colapse the waveform. Just accept it. Quantum mechanics is here to stay. As the Borg would say, resistance is futile.
antialias_physorg
3 / 5 (2) Feb 13, 2013
Rather than the photons which travel through both slits and are superimposed in flight. The dots distribution follows a classical calculatable wave interference, but like decaying atoms you never know where the next one will be till it has happened.

If that were the case they would fly through one slit or the other - because you could as easily put the screen at the slit (in which case you DON'T get an interference pattern)

But we DO see an interference pattern in the 2-slit experiment and hence they don't fly through either one slit or the other. So the 'dot' is not present until measured.

The photon is superimposed with itself because you get an interference pattern even if you space the photons so far apart that there is on average only one in the apparatus at any one time. (You can also do it with single electrons and get the same result)
GPhillip
not rated yet Feb 13, 2013
Thinking that Quantum Mechanics is just a temporary best solution and that something will come along later that makes more intuitive sense is just another way of trying to reject the science that has been proven to be absolutely accurate in 10's of thousands of experiments. Quantum Mechanics is no more a temporary best solution than the math of 2 and 2 = 4. It's correct and will always be correct and will not be proven incorrect at any point in the future. Of course we may find simpler expressions of the same concept as it is studied further. Einstein's original presentation of GR took grad level math abilities to understand, but after studying it for decades, simpler explanations of the same concept, without the complex math were possible.
As far as trying to explain paranormal phenomena with quantum effects, I'm afraid that is beyond the capabilities of the science. The scientific method requires experiments to be performed that can disprove the validity of a hypothesis.
GPhillip
not rated yet Feb 13, 2013
The very reason that some phenomena is classified as paranormal is that is cannot be subjected to falsification by experiment. So, some things like ghosts, UFO's, big foot, etc., are likely to always remain outside the capabilities of scientific investigation. Simply, science can not and does not provide an answer to everything. It has it's limitations.
ValeriaT
1 / 5 (5) Feb 13, 2013
The very reason that some phenomena is classified as paranormal is that is cannot be subjected to falsification by experiment
Unfortunately in contemporary physics many phenomena are ignored if not denied just because they depend on higher number of parameters, than the contemporary physicists can recognize. Typically the cold fusion and various psychic phenomena fall into this category: despite they're manifesting with quite tangible effects often, the general lack of reproducibility refuses the physicists who are motivated with safety and reliability of research, not with desire to reveal something new. Illustratively speaking, for modern physicists even the lightning is not real, until it cannot be reliably predicted and reproduced.
ValeriaT
1 / 5 (5) Feb 13, 2013
"refuses the physicists" should be "repels the physicists"
GPhillip
5 / 5 (2) Feb 15, 2013
I probably didn't say this well at all. Richard Hamming, a founder of modern computer science, said it much better:

Mathematics addresses only a part of human experience. Much of human experience does not fall under science or mathematics but under the philosophy of value, including ethics, aesthetics, and political philosophy. To assert that the world can be explained via mathematics amounts to an act of faith.

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