is there a logical way of understanding how randomness could agree with causality


by jadrian
Tags: agree, causality, logical, randomness
juanrga
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#37
Feb25-12, 12:22 PM
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Quote Quote by jadrian View Post
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...
jadrian
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#38
Feb26-12, 04:12 AM
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Quote Quote by juanrga View Post
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?
jadrian
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#39
Feb26-12, 04:19 AM
P: 143
Quote Quote by juanrga View Post
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 developement 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?
juanrga
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#40
Feb26-12, 10:19 AM
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Quote Quote by jadrian View Post
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.
questionpost
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#41
Feb26-12, 10:39 AM
P: 198
Quote Quote by juanrga View Post
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.
juanrga
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#42
Feb28-12, 05:04 AM
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Quote Quote by questionpost View Post
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.
questionpost
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#43
Feb28-12, 08:45 PM
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Quote Quote by juanrga View Post
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.
juanrga
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#44
Feb29-12, 05:32 AM
P: 476
Quote Quote by questionpost View Post
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.
ThomasT
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#45
Feb29-12, 06:59 AM
P: 1,414
Quote Quote by jadrian View Post
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.
questionpost
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#46
Feb29-12, 06:02 PM
P: 198
Quote Quote by juanrga View Post
"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.

Quote Quote by ThomasT View Post
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.
juanrga
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#47
Mar2-12, 05:15 AM
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Quote Quote by questionpost View Post
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).
jambaugh
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#48
Mar2-12, 06:33 AM
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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.
questionpost
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#49
Mar2-12, 07:14 AM
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Quote Quote by juanrga View Post
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...}
jadrian
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#50
Mar3-12, 05:25 AM
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Quote Quote by questionpost View Post
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 sence 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
ThomasT
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#51
Mar3-12, 06:45 AM
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Quote Quote by jadrian View Post
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.
Joncon
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#52
Mar3-12, 10:00 AM
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Quote Quote by ThomasT View Post
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.
questionpost
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#53
Mar3-12, 10:16 AM
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Quote Quote by jadrian View Post
in order for randomness to be true in a sence 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.

Quote Quote by Joncon View Post
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.
ThomasT
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#54
Mar3-12, 10:48 AM
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Quote Quote by Joncon View Post
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?


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