Physicist: With very few exceptions, yes. What we normally call “random” is not truly random, but only appears so. The randomness is a reflection of our ignorance about the thing being observed, rather than something inherent to it.
For example: If you know everything about a craps table, and everything about the dice being thrown, and everything about the air around the table, then you will be able to predict the outcome.
Not actually random.
If, on the other hand, you try to predict something like the moment that a radioactive atom will radioact, then you’ll find yourself at the corner of Poo Creek and No. Einstein and many others believed that the randomness of things like radioactive decay, photons going through polarizers, and other bizarre quantum effects could be explained and predicted if only we knew the “hidden variables” involved. Not surprisingly, this became known as “hidden variable theory”, and it turns out to be wrong.
If outcomes can be determined (by hidden variables or whatever), then any experiment will have a result. More importantly, any experiment will have a result whether or not you choose to do that experiment, because the result is written into the hidden variables before the experiment is even done. Like the dice, if you know all the variables in advance, then you don’t need to do the experiment (roll the dice, turn on the accelerator, etc.). The idea that every experiment has an outcome, regardless of whether or not you choose to do that experiment is called “the reality assumption”, and it should make a lot of sense. If you flip a coin, but don’t look at it, then it’ll land either heads or tails (this is an unobserved result) and it doesn’t make any difference if you look at it or not. In this case the hidden variable is “heads” or “tails”, and it’s only hidden because you haven’t looked at it.
It took a while, but hidden variable theory was eventually disproved by John Bell, who showed that there are lots of experiments that cannot have unmeasured results. Thus the results cannot be determined ahead of time, so there are no hidden variables, and the results are truly random. That is, if it is physically and mathematically impossible to predict the results, then the results are truly, fundamentally random.
What follows is answer gravy: a description of one of the experiments that demonstrates Bell’s inequality and shows that the reality assumption is false. If you’re already satisfied that true randomness exists, then there’s no reason to read on. Here’s the experiment:
The set up: A photon is fired at a down-converter, which converts it into two entangled photons. These photons then go through polarizers that are set at two different angles. Finally, photo-detectors measure whether a photon passes through their polarizer or not.
1) Generate a pair of entangled photons (you can do this with a down converter, which splits one photon into an entangled pair of photons).
2) Fire them at two polarizers.
3) Randomly change the angle of the polarizers after the photons are emitted. This prevents information about one measurement to affect the other, since that would require that the information travels faster than light.
4) Measure both photons (do they go through the polarizers (1) or not (0)?) and record the results.
The amazing thing about entangled photons is that they always give the same result when you measure them at the same angle. Entangled particles are in fact in a single state shared between the two particles. So by making a measurement with the polarizers at different angles we can measure what one photon would do at two different angles.
It has been experimentally verified that if the polarizers are set at angles 
We can do two experiments at 0°, 22.5°, 45°, 67.5°, and 90°. The reality assumption says that the results of all of these experiments exist, but unfortunately we can only do two at a time. So C(0°, 22.5°) = C(22.5°, 45°) = C(45°, 67.5°) = C(67.5°, 90°) = cos2(22.5°) = 0.85. Now based only on this, and the reality assumption, we know that if we were to do all of these experiments (instead of only two) then:
C(0°, 22.5°) = 0.85
C(0°, 45°) ≥ C(0°, 22.5°) + C(22.5°, 45°) -1 = 0.70
C(0°, 67.5°) ≥ C(0°, 45°) + C(45°, 67.5°) -1 = 0.55
C(0°, 90°) ≥ C(0°, 67.5°) + C(67.5°, 90°) – 1 = 0.40
That is, if we could hypothetically do all of the experiments at the same time we would find that the measurement at 0° and the measurement at 90° are the same at least 40% of the time. However, we find that C(0°, 90°) = cos2(90°) = 0 (they never give the same result).
Therefore, the result of an experiment only exists if the experiment is actually done.
Therefore, you can’t predict the result of the experiment before it’s done.
Therefore, true randomness exists.
As an aside, it turns out that the absolute randomness comes from the fact that every result of every interaction is expressed in parallel universes (you can’t predict two or more mutually exclusive, yet simultaneous results). “Parallel universes” are not nearly as exciting as they sound. Things are defined to be in different universes if they can’t coexist or interact. For example: in the double slit experiment a single photon goes through two slits. These two versions of the same photon exist in different universes from their own points of view (since they are mutually exclusive), but they are in the same universe from our perspective (since we can’t tell which slit they went through, and probably don’t care). Don’t worry about it too much all at once. You gotta pace your swearing.
As another aside, Bell’s Inequality only proves that the reality assumption and locality (nothing can travel faster then light) can’t both be true. However, locality (and relativity) work perfectly, and there are almost no physicists who are willing to give it up.
“Randomly change the angle of the polarizers after the photons are emitted.”
This statement assumes randomness already exists in the brain of the tester and the seemingly unmeasurable variables in the rest of the universe. You can not prove nor disprove a statement without assuming your result proving randomness doesn’t exist with implying randomness already exists.
It’s like describing the colour blue to a person that has never seen before. They may believe they understand the colour based on what the can visualise and they are not incorrect.
I believe that there is randomness from the human perception of results, however as the human viewing the results is limited in their ability to measure the variables without impacting the variables. Thus there would be no true way to prove randomness in anything but concept. If you are unable to prove the concept to be adaptable to real world experiments then you would fundamentally be saying it’s possible if it exists already. So something is true if it’s already assumed to be true but false if it’s already assumed to be false.
This was a very enjoyable read though, thank you for your time.
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@Sean
I totally missed the “Randomly change the angle” part…
You’re right… definitely an assumption there. I’m a programmer and have tried and tried to create true randomness from binary logic and cannot do it, so I’m inclined to say that it doesn’t exist. Perhaps I’m wrong in my own assumption but I died a little bit after reading this article until I read your comment. Thanks : )
You have to get down to the quantum level. If you created bits based on quantum uncertainty then you would have what you are looking for.
Therefore, you can’t predict the result of the experiment before it’s done.
Therefore, true randomness exists.
Im troubled by this. If the results of flipping a perfect but weighted coin are random how do you explain that the result would fail a frequency when the results would be prejudiced by the added weight.
I’m just confused about the idea of supposedly random numbers that contain a biased outcome.
“Therefore, you can’t predict the result of the experiment before it’s done.
Therefore, true randomness exists.”
Lack of predictability based on our current methods/intelligence/perspective can’t really give a definitive answer about randomness, we may not even be able to comprehend how everything works but that doesn’t conclude it therefore MUST be random.
Have we technically proven that there are things that exist outside of cause/effect or been able to perform an identical experiment and get different results?
(though I’m assuming we can never truly repeat any experiment unless we exist outside of time since the environment/conditions would be different, however minimal that difference may be)
I agree with Chris’ point. I think the biggest problem we face here is that the debate has included 2 questions. There is a big difference in being able to prove true randomness and perceived randomness. If you define randomness as something that can not be predicted by humans – then yes, randomness must exist. If you choose not to undertake study of circumstances then you will not know the result before the experiment has completed.
The other argument is if true randomness exists outside the realms of probability and predictability. Can an experiment that always produces a colour of red or blue as a result, ever produce a new colour just for no reason or rationality. Again, if you classify it by human perception then yes, if you stand at a different angle or “change your perspective/environment” then maybe you will SEE a different result – well that must be random.
The way I try and describe my thoughts on the matter to others is by taking a spec of dirt on the ground. If I knew every single force, decay, gravity, wind, water effect that has played a part on that spec of dirt – could I work out where it came from or which piece of rock it came from. I believe the answer is yes – but with a “but”. But it’s impossible for me to work all that out.. that doesn’t make me think it’s placement on the pavement next to me is random – just that I can’t perceive or even imagine the forces I would need to know to work out how it got there. I believe the rules of the universe are very specific and seem to return the same results time and time again.
This discussion is a bit deep for me but …
Predictability vs. randomness. I have one million dyed ping pong balls. They are all blue except for just one that is yellow.
If I reach in and “randomly” choose a ball it will always be blue (the yellow one is discarded as experimental error or disregarded as an outlier).
Please explain to me the nature of randomness and predictability in this scenario.
For extraccredit please distinguish between random, uncaused, and free will.
Nice that you tried to answer the question, but the answer is bogus.
This experiment fails to prove that all effecting variables are measured.
Answer to D. Peters. Sorry for answering so late. In a causal universe for any event there is a cause. What actually is a cause in our universe. It MUST be a form of energy. Further, randomness, if it exists, as opposed to deterministic, is something that appears for no cause, (it has unpredictable behaviour also), and therefore it does not require any energy to kick start. So, it would be a free lunch! The only exception is the Big Bang that we still do not understand i.e. where the total energy (“white” mass, dark mass and dark energy) in cosmos came from!
To put it short. If there is a cause it’s predictable, by the application of physical laws. If it is random its unpredictable by definition. To me the randomness is contrary to
common sense.
Finally, about Heisenberg’s principle. I would like to see it coupled with dark energy and the medium through the particles are moving when disturbed by light from the observer. I would say that it is only a first approximation of the reality at quantum level. We need to go 40 orders of magnitude lower into the micro-cosmos. Same as with theory of relativity – you need to go far enough from a mass to notice dark energy and the accelerated expansion of space. “Near” a large mass such as stars, general relativity works fine, no cosmological constant (dark energy) noticeable!
Understand what you are saying and yes the free lunch thing is generally indication that something is amiss (would you like to buy my perpetual motion machine?) There is however the case where particles at the quantum level can pop in and out of existence. Appearing to have a free lunch but paying it back shortly there after. There is no observable cause for this under the current model which displays what we would normally cause randomness. Of course the deeper we go into this discussion the more I am out of my depth.
First off, fantastic article and commentary by all of the above posters. I just wanted to bring up a few points that crossed my mind as I read through everyone’s thoughts:
The interplay between randomness and causality is very intriguing. For instance in the experiment above, they measured entangled particles – I wonder what difference the time frame variables made on the outcome? For instance if you fire the entangled particles now, versus one second later would the results shift….same for which particular particle you use. Theoretically if you could use the same particle pair repeatedly(can’t because of polarizer) would it continuously yield the same/consistent results?
The arrow of time seems to be a big player here. The only way to know for certain if predetermination is playing a role would be to go backwards in time and run the same experiment on the same particle in the same timeframe twice and check the results against each other.
Another point I wanted to touch on is randomness and human perception. As stated above I question a modern computers ability to generate true randomness when picking the angles within the experiment. As far as I know digitized randomness has not been achieved yet, as it would be the holy grail of cryptology – Quantum computing may of course change this in the future, but even if we somehow based a bitlike structure off of Heisenberg’s uncertainty principle, we are running into questions of causality.
The human mind naturally tends to look for patterns, as stated in the article we like to attribute sufficiently complex actions to randomness when in fact it is a limitation on our ability to perceive a situation properly. If we could somehow view reality in all of the possible perceptions of it combined and at once, then anything which was still unexplainable and truly without a pattern would be randomness.
However, what if this randomness was due to some type of orderly process, existing say within a higher dimension? then is it truly random, or are we again running into a lack of proper perception?
The last thing I want to throw out for consideration: a computer that is able to fully simulate every aspect of reality from the vastness of the universe, down to the spins of each individual atom would have to be bigger than the universe itself. Therefore any simulations we run will be at best very very close rough approximations. Consider then the butterfly effect, can we ever really truly measure things existing outside of the conceptual IE mathematics on paper, or just get ridiculously close? Pragmatically I guess it doesn’t matter, but theoretically its turtles all the way down 🙂
Truly inspiring article…
Randomness is something that is beyond our measure. This may imply that it has some order which is of too large scale. Okay… But the problem is when the too large becomes
something like ” infinity “. It obviously depends on our definition. For example, you may say that two parallel lines ” never meet ” or ” they meet at INFINITY “.
Can you always predict with 100% accuracy what you will be thinking after (say)27 minutes ?
You will find it hard; this is because even our actions at macroscopic level are almost
random. And it is clear from Heisenberg’s principle; we don’t see any level of certainty
possible there.
And consider De Broglie’s hypothesis, which accuses matter having dual nature with
a specific wavelength. Again, we cannot think of ourselves being waves, as we have a De Broglie wavelength that is negligible COMPARED to our units. But for a hypothetical observer of about 10^10 or more times larger than us, he would experience
us as waves….( Imagine his units).
As the size of a body decreases (with respect to size of universe), the more uncertain and random it seems.
But this does not imply that every random event can be decoded at microscopic level,
i.e; its large sequence, since the pattern may extend up to infinity without any
OBSERVABLE (for us) order. It is something like asking the value of 0/0, which has infinite answers….
So it is almost impossible for a modern physicist to not believe in uncertainty and randomness.
If we’re talking about causation and outcomes of events then we would likely want to trace all events through their preceding causes and ultimately the first uncaused cause; what Aristotle named the ‘Prime Mover’. So really it’s a question of how the Prime Mover emitted the pure energy in what is is called the Big Bang. All attributes of our universe such as the law of gravity, dark energy and matter, etc were contained in that initial moment of the creation of space, time, energy and consequently matter. To fully understand the degree of randomness in our Universe would require us to not be a part of or somehow independent of the Universe entirely. What I am referring to is true objective knowledge, which science or mathematics can never truly attain as they are human constructs. We can approximate the truth of the degree of randomness in our Universe to the extent allowed by the Prime Mover in its inception.
And if this primus motor accually was “caused” by a random event, or if it encoded true randomness as a consequence?
A truly awful answer. The math doesn’t make sense (the demonstration with the probabilities is very unclear; the sequence of equations do not follow from each other without added information that is not explicited by the author) and the experiment used proclaims a revolutionary result based on very weak assumption (“we’ll just assume we know everything there is to know about our setup”).
By the same token, I’ll assume I know everything there is to know about coin flipping, flip a coin, realize I couldn’t predict the result from my perfect knowledge, and conclude that randomness exist.
What a waste of time.
“I will restate that: it is impossible to accurately predict the outcome and the impossibility is an inherent part of the universe and provides for a model that represents experimental outcome at a level where no other model can.”
“The theory fails to predict an effect, let’s assume the effect is wrong.” … Also the response to Jim Nazium was hilariously absurd.
You’re making it too complicated. Things in the universe do not have attributes until we measure them. Electrons aren’t everywhere, they do not possess the attribute of position until we ask the question (can you prove they do? If not Occam’s razor guides us). It’s not that the attributes are “spread out”, they just don’t exist.
I found this difficult to swallow for years, because our egocentric view of the world wants there to be an objective, continuous, and specific reality and we can not easily disabuse ourselves of that belief. As Einstein said, “Common sense is simply that set of prejudices we learn in childhood”. (Paraphrased and he probably said it German anyway).
I had a devil of a time with this for decades, but once I broke down the egocentricity it all seemed, possible, clear, and even simple.
Quantum Mechanics is about reality; classical mechanics is about sensory illusions.
Technically speaking, if someone were to impossibly know how every particle in the universe is going to interact with eachother, there would be no randomness. So in a sort of sense, true randomness is impossible to achieve. But saying that knowing that sort of information is impossible in itself, true randomness to us does exist because of our lack of knowledge. So it can easily go either way.
It seems that much of the argument for true randomness is based on a comfort bias towards the idea of free will and uniqueness.
Denying the idea of superdeterminism undermines the validity of Bell’s experiment. The experimenter IS part of the system.
Wave functions collapsing on observation may very well be the experimenter determining which of the many worlds he is occupying. To think that observation carries the power of control seems presumptuous, even spiritual.
My comment here is not an argument.
As Einstein said of general relativity “it is too beautiful to be wrong” we can (and I do and stand in utter awe) observe order arising spontaneously out of chaos.
That is to say chaos can self-organize. Amazing.
What a beautiful thing our apparent reality is, not to mention whatever underlying “thing” (hmmm, this smell suspiciously of the aether) is even more beautiful.
This is the understanding our very best philosophers and physicists have bequeathed upon us.
And who can say what tomorrow holds?
– Greg
I have been following everyone’s input on this topic for a long time now. I think I have reached the limits to what I can add or take from it now. I keep coming back to the same question in my head. Can something happen for no reason at all? Not just the stuff that humans can perceive.
If the answer is yes, then I would concede that true randomness is possible.
Fascinating thread. Way too heavy for me but fun anyway. My modest two cents: since creation, causation reigns. Any randomness is subjective.
Hi all. Absolutely fascinating & i must confess my knowledge of quantuym physics is next to zero. However I have been working on “randomness” in roulette.
In online roulette the chances of anything happening is controlled by man made-RGN s, so therefore cannot be random
However in a bricks & mortar casino the same will not be the case. It is nature, the laws of physics, chemistry etc.
My question is; if true randomness exists (uncontrolled by any laws) why is there a maximum amount of consequetive times an individual number repeats or times heads will show after flipping a coin?
Excuse the poor way I have framed the question but really intrigued.
Really good article and great comments… unfortunately, the article is biased in that Bell’s experiment does in fact support a deterministic alternate quantum theory known at the Pilot Wave aka Bohmian-Mechanics. Ref: findings in Feb 2016. This theory implies that the electron actually exist at a specific area and it is not our observation of it which causes it to “be”… It predicts that it is only our lack of knowledge/info which prevents us knowing what state/spin/area the electron is in, etc… a very good intro on Bohmian Mechanics is this one: https://www.youtube.com/watch?v=rbRVnC92sMs. Supporters of this theory also have their own website.
Note: The above data doesn’t necessarily represent my own opinion about this topic but is simply intended to readjust the debate in including the latest known variable/info known to the scientific community.
Now, if we picture the universe on a two dimensional plan with X and Y axis, all the points on this axis are legitimate and energy flowing in the universe could be witnessed by an observer as waves/patterns on this grid. Also from a philosophical & mathematical standpoint, if we concede that our universe includes the concept of infinity then, for one to be able to predict every interactions within the universe, one would require to know all the information within that specific universe. Since this universe is infinite, one would require being greater than this infinity to include all this info + observe it at a distance; and this, to avoid being impacted/influenced by that universe and therefore biased.
In math, this can be translated into the concept of dimensions i.e. “U” (our universe) at the power or “u” where “u” is the new dimension allowing a new infinity of possibilities to the already existing smaller infinity of possibilities.
Now, this appears to me that our universe is the victim of its own fabric where it includes both opened (infinity) and closed concepts (order). To exist, it has to be an hybrid of both these two concepts.
Is it that true randomness exists but it must be relative to the perspective of the observer OR does the fact of including infinity in the equation automatically implies some form of randomness… or it is a third possibility i.e. an hybrid possibility including both concepts. This creates an endless spiral of possibilities.
Any thoughts?
Happy having shared with you.
Hi, I ve seen your link. Very interesting. Thanks for that.
Jon
When we refer to ‘randomness’ in the context of quantum mechanics we are generally referring to the kinetic behavior of subatomic particles. Perhaps we may never know whether or not the kinetic behavior of subatomic particles is ontologically [fundamentally] random, as the absence of evidence for any patterns in their kinetic behavior does not necessarily mean evidence for the absence of any hidden patterns therein. Nevertheless, based on the fact that decades of research by some of the best minds of the past one hundred years has failed to unearth any patterns in the kinetic behavior of these particles, the said behavior of these particles may be treated as, at least for now and at least prima facie, ontologically random. Incidentally, our common [communal] sense is based on our common [communal] experience/observation of the features of the universe that we have hitherto communally experienced/observed, and as such common sense cannot be employed to make one hundred percent correct deductions about the features of the universe we have not communally experienced/observed yet _ just because everything we have experienced/observed so far has a cause, it does not necessarily follow that everything does indeed have a cause or require a cause. One of the fundamental assumptions of science is that the existence is contingent [contingency theorem] in that existence could exist in any which way it may exist and hence the laws of science cannot be derived using pen and paper alone as opposed to the way we derive theorems of mathematics. This is the main reason why research/observation/experiment is so fundamental to science and why Feynman said, ‘experiment is the test of truth in physics’ and ‘it does not matter how beautiful a theory is or who comes up with it, if it does not agree with experiment it is wrong’. Common sense, intuition, aesthetics or even mathematical elegance does not dictate existential reality _ to think they do is nothing but sheer hubris.
Thats an awful lot of typing to say we don’t really know. but it was fun stretching the old brain cell (singular) I think, maybe , not really certain any more ? Thanks.
Randomness on the scale you have illustrated seems to be logical but is there order in multiple occurrences of randomness? Bell does not seem to fully explain this. What am I missing?
Hmm well they clearly haven’t seen this: https://www.youtube.com/watch?v=Onzj-jNCa9A .
In
…
3) Randomly change the angle of the polarizers after the photons are emitted.
…
you imply that you can randomly change the angle of polarizers (as Sean has already pointed out). That means you assume true randomness exists and the whole setup gets somewhat circular. By already assuming true randomness exists you proove.. that true randomness exists 🙂
Now even if we assume that a pseudo random number generator would exist or could be built so that we would perceive it as true randomness, that pseudo random generator needs not only to give really good pseudo random numbers, but would also need to provide those numbers FAST, which makes it quite a challenge, but not impossible.
So what you really need to look out for is a way to find a FAST PSEUDO random number generator. Radioactive decay at a particular atom seems to be random, that would be an area of high interest for further experiments.
Great article, but I’m with the first Sean who replied, pointing out how the experiment begs the question. I’m not sure whether randomness exists.
Maybe some day the scientists will understand some internal causes of ‘random’ quantum effects and they will turn out to be deterministic and not random?
Maybe some day we will discover particles that interact with the known particles, say, electrons, but do not change their properties, so it will be possible to measure with high precision both: location and speed of an electron.
Also I am not convinced you can predict on what side the dice will fall if you know ‘the dice, the cube, the table and the air’. Can anyone please prove this? The dice consists of atoms that ‘truly randomly?’ move, so in some circumstances a random movement of an atom can change the side the dice will fall on.
As the original questioner, I didnt realise that atoms randomly move, as in whilst tossing a coin. But having said that, how do we know these movements are random?
I think for atoms they maybe not random, but you don’t know speed and position of each atom in coin, so for you they are random. If you watch every atom of coin in electronic microscope in order to know their positions and velocities, you may change atom positions, as you send an electron beam on them.
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Why is it that so many physicists are certain that certain quantum attributes are truly random but equally certain that nothing else in nature is? I am trying to understand how someone can simultaneously believe in randomness at the quantum level but also be a reductionist who believes in determinism. Feels like fine tuning to me.
@Darrell Burgan
I totally sympathize. Physicists do seem to be having and eating their cake, but in this case it’s valid. There’s a post here that (hopefully) addresses your concern.
@The Physicist
Thanks for your reply.
I’m not at all denying that QM has certain aspects that strongly appear to be based on honest-to-goodness true randomness. Unless Bohmian mechanics prove true, it seems clear the QM world has true randomness in there somewhere.
The part I’m have trouble with is understanding why we immediately deny true randomness takes place anywhere *but* in the QM world.
When I look at emergent phenomena (e.g. life from biochemistry from chemistry from physics), I see multiple major leaps in complexity that I find very difficult to believe could reduce completely down to a bunch of strings wiggling a certain way. I believe much of our universe reduces down but I also believe it is plausible to say that there is macroscopic randomness in our universe as well. I’m skeptical of strict reductionism.
The reason I ask, I am trying to wrap my head around how to approach the hard problem of AI, which is really to define what consciousness is and where it comes from. Without randomness, then consciousness must be a mere clock-work that reduces completely down to those squiggly strings, and I just don’t accept that something as incredibly complex as consciousness could be fully reducible. There is a real emergence of new behavior here that I am very skeptical can be written off as just another deterministic butterfly effect.
So I’m curious – do physicists really deny that there could be true randomness outside the QM world, and on what grounds do they object? Have they *proven* that all macroscopic effects have QM causes at their root? Have they *proven* that all macroscopic events are deterministic? I’d love to read the papers if they have.
So, what I’m taking from this is that true randomness can only exist within a non-causal reality – in a universe where things can happen for no reason at all. In such a universe, it would seem that the laws of physics are not really laws at all, but merely patterns observed among specific events which are neither universal nor immutable.
If however, we consider it axiomatic that every event is both the effect of one or more previous events and the cause of one or more subsequent effects and that those causes and effects are governed inextricably by pre-existing natural laws, then true randomness cannot exist. It is merely the human perception of a situation in which it is impossible or impractical to account for all of the variables that produce a given outcome.
What about the situation where events can be measured to happen with a certain probability. Eg radioactive half-life where things arent strictly random yet appear not to be causally linked to anything? Is that really ‘truly random’?
We have a dice and we know that probability of it falling on one if it’s sides is 1/6 and that it is uniformly distributed. But if we build a device which will use videocamera and computer to measure initial angle, height from the floor, then knowing stiffness of the floor and of the dice we can calculate with very high probability what outcome will be produced. The dice plus such device is already not a random, but rather a deterministic sysyem.
For quantum effects at the current level of science we cannot calculate the outcome of a quantum experiment. So currently quantum systems are pure random for us. But if in the future science will be able to calculate, i.e. predict the outcome of a quantum experiment, quantum effects will stop being pure random.
David, we can put it like this: if you cannot predict an event with higher probability than it happens, the system is purely random for you. If probability of an atom to decay within the next month is 1/4 and you correctly guess that it will decay within one month in 1/4 of the cases (if you repeat the experiment many times), then it is pure randomness.
But if somehow in the future scientists will discover some way to predict atom decay with probability greater than 1/4 than it will be not pure randomness.
Not a scientist.
It seems to me that a lot of the argument for the existence of randomness is put forth describing the seemingly random decay rate of radioactive particles.
Can it not be said that while they may appear random it is even just as possible that the point of decay for a particular particle was pre-determined by unknown variables? You may not be able to look at a single particle and say it will decay at this point in time, but if you took that exact particle and put it in the exact circumstances at the exact same time, would it not still decay exactly the same? I do not know if this is true or not, but my way of thinking causes me to believe it is.
While it may not ever be possible to predict everything in the universe due to the inability to know all things at all times this does not mean randomness exists. Only that we cannot measure it.
“But if in the future science will be able to calculate, i.e. predict the outcome of a quantum experiment, quantum effects will stop being pure random.”
The current science says that *in principle* we cannot predict the outcome of a quantum experiment. The Bell Inequalities proved that either these things are truly random, or locality cannot hold.
My gripe is that if we are to allow non-causal randomness in one place, why must the whole of nature elsewhere be completely and utterly causal? I am deeply skeptical that macroscopic behavior like life can emerge deterministically from a system as simple as QM. I believe that Mr. Godel has something to say about determinism and completeness as well.
“The current science says that *in principle* we cannot predict the outcome of a quantum experiment.”
The future science may say: Now we can predict.
What I dont get as the parent questioner, in my poor layman terms, I am no expert, is that for something to be accepted as a truth it has to be replicated in controlled conditions.
If this is the case, then how can “randomness” be proven?
If the assumption is that after shuffling a pack of cards any card shown will be random, this doesnt prove randomness, it just proves we are incapable of understanding which card comes next. If you state ” I can prove randomness exists because I cannot determine the next card”, are you not just ignorant of the sciences involved, so because “we” cant see a causal affect then its obvious one does not exist?
Nobody ever proves randomness, it is not a theorem. Randomness is a condition when you don’t know the outcome of an experiment. It can be that somebody else is able to predict the outcome, so for him/her it is not random, but if you cannot predict, it is random for you.
In the experiment with entangled particles: imagine someone performs experiment with quantum effects and before it he says what the outcome will be and it always happens that he correctly guesses the outcome. Scientists proved that this is impossible, because this “someone” is made of same particles as our universe and is subject to same laws as the particles he is experimenting with. But what if that “person” is made of different substance that yet to be discovered and that substance is not subject to laws of quantum mechanics and so he is able to measure particle location and speed together with high precision?
The true randomness of quantum effects is true based in the proposition that quantum mechanics is true for all particles and all conditions in our universe. Until now this is what has been confirmed in numerous experiments and observations. But scientists do observe what they are able to observe at the current level of technology. Who knows what they will discover in the future?