Can Randomness and Causality Coexist Logically?

In summary, the conversation discusses the concept of randomness in reality and its relationship to causality. The speakers explore different perspectives and theories, including Bohmian Mechanics and the idea that randomness is a lack of information about the causes of events. They also mention the role of probability in quantum mechanics and the potential limitations of our understanding and ability to observe the universe.
  • #36
luckis11 said:
In probability theory each roulette result is considered indepedent from any past events, however this assumption does not disagree with the possibility that all future events are predetermined by past events (determinism) like the orbits in an elastic collision simulator. The question is whether all events are determined by past events, or a human has the freedom to choose more than one choices like an elastic collision simulator where the future orbits of the spheres are not determined by the past orbits because some balls can choose to go up or down instead of the otherwise predetermined down orbit. Double slit experiment indicated nothing more than determinism, because indeed it's impossible to predict where each next "electron" or "photon" (dot on the film) will appear, but after many dots appear, the wave interference tossils shape on the film. So, quantum seems a little useless to answer the question, it's better to think on it supposing that where the roulette ball landed, was determined from the moment it left the hand of the dealer (which is rather false), and then wonder, was that dealer's choice predetermined by the events that took place an hour ago?

There's a lot of factors that are "probable" and would be relatively predictable but only because they happen in such slow rate of time. If you throw a ball, you can predict a relative area that it's likely to land even thought there's plenty of air molecules that could fractal-ly distribute energy in random ordinances as to cause it to move slightly one way or another and it's really not that much force and speed, so there's smaller parameters for where it could go. Or say I launch a rocket. If it uses virtually no energy to lift itself off the ground, you can predict with like 99% certainty it won't even make it off the ground, and so the area it will end up in is where it started. However, if you give it a ton of NO2, there's like a 1 mile radius of where it could possibly end up.
I suppose at this point there just isn't enough evidence to really determined it's either, but so far there is no evidence that there is actually something that determines with 100% certainty where particles move and where everything will ultimately end up, and since there's nothing determining them, things are free to happen in random orders as far as our evidence shows.
You'd also have to consider how probability dies how, but also how force and energy distribute through an object. At macroscopic distances, particles don't really appear and disappear much because their wave function's die down at those distances. However, the exchange of energy and force happens on a molecular levels and so how energy and forces distribute is still random with areas of probability.
As far as our consciousness goes, we don't really know if it occupies the classical realm or the macroscopic realm or really what it is, so it's hard to say how it effects things.
 
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  • #37
jadrian said:
not to be impolite, but i truly view randomness in reality as something you can trick your kids into accepting along with santa, the tooth fairy etc.

when compared to causality the idea of true randomness existing in reality seems incredibly weak to me.

is there any logical way to reconcile the two?

First, randomness is perfectly compatible with causality.

Second, science is based in data and scientific method, not in personal beliefs/ruminations. Yes that ancient Pope was incredibly sure that Earth did not turn around Sun but...
 
  • #38
juanrga said:
First, randomness is perfectly compatible with causality.

Second, science is based in data and scientific method, not in personal beliefs/ruminations. Yes that ancient Pope was incredibly sure that Earth did not turn around Sun but...

what are you doing here. random is defined as something of which we cannot see its cause. so true randomness would have no cause. do you think thinks through?
 
  • #39
juanrga said:
First, randomness is perfectly compatible with causality.

Second, science is based in data and scientific method, not in personal beliefs/ruminations. Yes that ancient Pope was incredibly sure that Earth did not turn around Sun but...

are you still holding fast to the free will axiom haha of the copenhagen interpretation?

do you think the chemistry in your body has magic involved, as opposed to a burning flame?

heres some info that might cause indigestion


Originally Posted by kith View Post

Just out of curiosity: how do you decide what to do in a given situation? ;-)

my respons- everything that occurs in my body is a chemical reaction. all the chemical reactions are mediated/controlled via enzymes which are produced in quantities resulting in positive and negative feedback chemical reactions which ultimately react with dna as the homeostatic instruction manual.

my brain has developed partly through instinctual developments from my dna ie arachnophobia, and partly as a response to my environment, always ultimately controlled by dna which grows our brain into a tool to cope with a complex environment, always looking out for its survival, and eventual reproduction, not because the genes goal is reproduction, but because our genes are replications of genes that had a proclivity to reproduce. do you know why jealosy is one of the strongest and most violence producing emotion? its because our dna has strongly embedded in our brains development a defense against somebody else impregnating your reproductive partner with other than your genes, resulting in your genetic death if you do not reproduce because of foreign adultery.

my choices are the end result of a causal continuum of millions of neural interactions, ultimately leading me to make the best decision in the interest of my genes. why does a male preying mantis let itself get eaten by the female after mating? because the added nutrition to the female will result in a more favorable genetic outcome (more eggs with its genes inside) than running away.

we are exercising our brains on a website because of complex psychological reasons that ultimately benefit our many aspects that could be considered in the genes interest.

why am i writing this post? because my self sustaining chemical reaction has effectively directed me to do it for reasons you can ask an evolutionary minded psychologist.

the chemical reactions that occur in my body and brrain are fundamentally indistinguishable from a burning flame or pouring acid into a buffer solution.

so to think that there is somebody behind the wheel in my brain calling the shots is an infantile notion. i have no more choice than any other chemical reaction that we would regard as nonliving.

let me ask you a question. Do you think you are alive?
 
  • #40
jadrian said:
what are you doing here. random is defined as something of which we cannot see its cause. so true randomness would have no cause. do you think thinks through?

Random is not that. You confound determinism with causality.
 
  • #41
juanrga said:
Random is not that. You confound determinism with causality.

Ok, well "spontaneousity" is in an event which we can't see a cause, but randomness is that we can't see a clear pattern to predict future information off of, and if there's no way to predict future information, how could everything be determined? And if you say "well that's just because we don't know what's determining everything", then maybe this thread should be moved to the speculation section.
 
  • #42
questionpost said:
Ok, well "spontaneousity" is in an event which we can't see a cause

I do not know what you mean by "spontaneousity", but the standard term spontaneous to refer to certain kind of processes (spontaneous processes) is causal. The cause of spontaneous evolution A→B is traced to the instability of the initial state A, which can be quantified.
 
  • #43
juanrga said:
I do not know what you mean by "spontaneousity", but the standard term spontaneous to refer to certain kind of processes (spontaneous processes) is causal. The cause of spontaneous evolution A→B is traced to the instability of the initial state A, which can be quantified.
Except if it's spontaneous how did "A" get there in the first place? We see atoms in random statistical locations with no apparent cause for them being in the specific location that we measure them in.
 
  • #44
questionpost said:
Except if it's spontaneous how did "A" get there in the first place? We see atoms in random statistical locations with no apparent cause for them being in the specific location that we measure them in.

"Spontaneous" refer to the process, not to the initial state. In any case, the initial unstable state is also obtained in agreement with causality. That is the reason which scientists are able to prepare systems in unstable states in their labs.

It seems that you also confound randomness with causality: A→B is deterministic and causal; A→{B1,B2,B3,...} is not deterministic but causal.
 
  • #45
jadrian said:
when compared to causality the idea of true randomness existing in reality seems incredibly weak to me.

is there any logical way to reconcile the two?
First, please follow the conventions of written English. Capitalize where necessary (eg., wrt the first letter of the first word in a sentence).

To reply to your question, yes, the experience of randomness and the assumption of determinism are reconcilable/compatible.
 
  • #46
juanrga said:
"Spontaneous" refer to the process, not to the initial state. In any case, the initial unstable state is also obtained in agreement with causality. That is the reason which scientists are able to prepare systems in unstable states in their labs.

It seems that you also confound randomness with causality: A→B is deterministic and causal; A→{B1,B2,B3,...} is not deterministic but causal.

Is "if you flip a coin there's a 50% chance of heads or tails" causal? In either case, there's still not evidence for something actually "causing" us to measure particles in the specific locations we measure them in.

ThomasT said:
First, please follow the conventions of written English. Capitalize where necessary (eg., wrt the first letter of the first word in a sentence).

This is not an English forum which you'd know if you knew how to read well. As long as you understand what's being said it doesn't matter.
 
  • #47
questionpost said:
Is "if you flip a coin there's a 50% chance of heads or tails" causal? In either case, there's still not evidence for something actually "causing" us to measure particles in the specific locations we measure them in.

Maybe you would read your own phrase: "if you flip".

I do not know what you mean by "evidence", but the available theories of localization are causal (although non-deterministic).
 
  • #48
I thought that I would weigh in on the OP question. This question has been under debate from the inception of QM. As with the twin "paradox" in relativity the first step in resolving it (other than dismissing QM) is to carefully parse the question under the new definitions of the new theory.

What does one mean by "causality" or "determinism"? Here are some formal operational definitions based on the understanding in QM that we do not speak about values we do not observe.

1.) determinism of effect: Given a well defined quantum system and a known intermediate dynamic, can we assure a given future measurement of a specific value by controlling the initial conditions? In QM the answer is yes.
2.) determinism of cause: (Dual to the above) Given a well defined quantum system and a known intermediate dynamic, can we be assured of a specific value of a given past measurement by a future observation? In QM the answer is yes.

These two seem to say the same thing but not quite.

3.) complete determinism i.e. classical determinism: Given a well defined system and known intermediate dynamic, can we know the outcome of every possible future measurement by controlling the initial conditions? or equivalently ...can we know the values of every possible past measurement by future observations? In orthodox QM this is not possible since it violates complementarity.

The equivalence here and its lack in the first two shows how complementarity invalidates the classical notion of a system state. Even asking the question of whether the universe is a clockwork is invalidated in QM. It isn't that the answer is "no" (or "yes") but that the question is invalid. It is like asking "which twin is older" in SR negating the relativity of time and simultaneity.

In QM one has relativity of state or relativity of "reality" in that one can only parse classical questions when working in a particular frame of commuting observables. In SR you can transform between inertial frames mixing time and space, showing how different observers answer the question of "which twin is older at a given t value on my time coordinate". In QM the transformation between "reality frames" mixes certainty with spontaneity, i.e. it mixes information with noise. The QM transformation rules don't tell us how what one set of measurements yield transform to what another set of measurements yield, but rather how the expectation values of one set of measurements transform to the expectation values of another set of measurements. These expectation values include such things as variance which express degrees of uncertainty in the measurement.
(e.g. [itex] E(x^2) \ne (E(x))^2[/itex]

One may feel less than satisfied with the loss of certainty, i.e. Einstein's worry of incompleteness, however QM is complete in a different way, it is a theory formulated in a more complete context (probabilistic descriptions which allow for P=1 certain subcases).

In summary, QM is deterministic ( 1 and 2 above) in that dynamic evolution maps the three entities: {system,observable, measured value} in a 1 to 1 way between past and future cases. It indeed maps all such triples to correspondents. But it also conserves the logic of complementarity and the uncertainty principle when we consider what measurements we made/are making/will make and what expectation values were/are/will be associated with them. In the above mapping only one such triple (for complete observables or one set of compatible triples) is valid in a given instance of the system.
 
  • #49
juanrga said:
Maybe you would read your own phrase: "if you flip".

I do not know what you mean by "evidence", but the available theories of localization are causal (although non-deterministic).

Finding the location of a particle or seeing perfectly how energy will distribute is like flipping a coin. Also, at this point, there is no evidence that we can see "causes" everything to act the way it does, because that would require us to find out what "causes" particles to appear in the exact locations that they do, and there isn't really a predicted lower-level of matter that can create quarks and electrons. A particle appearing in a location or even throwing a ball can cause something, but there isn't a specific causation pattern which you can always depend upon in which you even know of a specific probability of outcomes. So it's chance that A->{B, C, D...}
 
  • #50
questionpost said:
Finding the location of a particle or seeing perfectly how energy will distribute is like flipping a coin. Also, at this point, there is no evidence that we can see "causes" everything to act the way it does, because that would require us to find out what "causes" particles to appear in the exact locations that they do, and there isn't really a predicted lower-level of matter that can create quarks and electrons. A particle appearing in a location or even throwing a ball can cause something, but there isn't a specific causation pattern which you can always depend upon in which you even know of a specific probability of outcomes. So it's chance that A->{B, C, D...}

in order for randomness to be true in a sense you might have to regard the electron to be moving not at c, but at INFINITE speed to result in the conclusion that it is undefined. also the assumption of randomness in qm leading to what we consider very precise compared to everyday measurement but might be grossly imprecise compared with absolute prediction, does not mean we should be forced to accept randomness
 
  • #51
jadrian said:
not to be impolite, but i truly view randomness in reality as something you can trick your kids into accepting along with santa, the tooth fairy etc.

when compared to causality the idea of true randomness existing in reality seems incredibly weak to me.

is there any logical way to reconcile the two?
Not that I know of. So, I agree with you. That is, given the extant physical evidence, the assumption of a fundamental determinism seems to me to be more reasonable than the assumption of a fundamental indeterminism or randomness.

I think you can sleep well tonight with the assumption that the world isn't suddenly going to do anything ... really weird.
 
  • #52
ThomasT said:
Not that I know of. So, I agree with you. That is, given the extant physical evidence, the assumption of a fundamental determinism seems to me to be more reasonable than the assumption of a fundamental indeterminism or randomness.

I think you can sleep well tonight with the assumption that the world isn't suddenly going to do anything ... really weird.

Why does it have to be one or the other? The universe clearly is deterministic to a large degree but why is a certain amount of randomness such a problem? I'm not saying true randomness exists but you can't rule it out simply because you don't like the idea.
 
  • #53
jadrian said:
in order for randomness to be true in a sense you might have to regard the electron to be moving not at c, but at INFINITE speed to result in the conclusion that it is undefined. also the assumption of randomness in qm leading to what we consider very precise compared to everyday measurement but might be grossly imprecise compared with absolute prediction, does not mean we should be forced to accept randomness

Electrons don't move at infinite speed...
Things like randomness and causality seem to make more sense in quantum field theory, because instead of everything existing as these solid objects that have to cause something and lead to another event, everything, all matter, exists as a culmination of different fields of probability whos shapes change depending on different circumstances. This way, you can still have randomness but also have a high probability of one event making another event to be probable.

Joncon said:
Why does it have to be one or the other? The universe clearly is deterministic to a large degree

Do you have evidence to support that? Because for all we know the universe could be infinitely large and therefore has infinite factors.
 
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  • #54
Joncon said:
Why does it have to be one or the other? The universe clearly is deterministic to a large degree but why is a certain amount of randomness such a problem? I'm not saying true randomness exists but you can't rule it out simply because you don't like the idea.
It isn't one or the other. Randomness refers to unpredictability. Obviously, lots of things are unpredictable. If one assumes fundamental determinism, then this unpredictablility is just a function of our ignorance. And I suppose you're right, fundamental randomness or indeterminism can't be ruled out. But given the more or less orderly and predictable evolution of our universe, then that doesn't seem like a very good assumption to me.

This thread is in the wrong forum. Why hasn't it been put into Philosopy or General Discussion yet?
 
  • #55
ThomasT said:
This thread is in the wrong forum. Why hasn't it been put into Philosopy or General Discussion yet?

Because
questionpost said:
Electrons don't move at infinite speed...
Things like randomness and causality seem to make more sense in quantum field theory, because instead of everything existing as these solid objects that have to cause something and lead to another event, everything, all matter, exists as a culmination of different fields of probability whos shapes change depending on different circumstances. This way, you can still have randomness but also have a high probability of one event making another event to be probable.
 
  • #56
jambaugh said:
...

1.) determinism of effect: Given a well defined quantum system and a known intermediate dynamic, can we assure a given future measurement of a specific value by controlling the initial conditions? In QM the answer is yes.
2.) determinism of cause: (Dual to the above) Given a well defined quantum system and a known intermediate dynamic, can we be assured of a specific value of a given past measurement by a future observation? In QM the answer is yes.

...

I like to think of this: you can see one step forward and one step back, but there is no certainty as to the depth of how far back or forward you can go (or need to go) to determine causality.
 

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