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About randomness & determinism- NOT another free will argument.

  1. Nov 20, 2004 #1


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    I'm interested in exploring the nature and methods of defining random and determined events. Please forget, at least for now, their applications to free will.

    For example, is there some reason for defining one in terms of the other, as in: An event is random if [conditions].
    An event is determined if it is not random.

    Are randomness & determinism comparable to hotness & coldness? i.e. as relative positions on a scale. Is one really the relative absence of the other? Would such a distinction be arbitrary? The idea of varying degrees of determinism seems contradictory, but varying degrees of randomness seem admissible, even inherent.

    And so on. Don't be stingy- Share your brain!

    Happy thoughts,
  2. jcsd
  3. Nov 20, 2004 #2
    A little (but not much) off topic: recommend you read Stephen Wolfram's "A New Kind of Science," in which he deals with our perception of randomness (among many other things)!

    ---- Bill
  4. Nov 20, 2004 #3

    I am not sure that there is such a thing as true randomness , the USA military go to all sorts of lengths to get this for security purposes and they sometimes sound ridiculous . One of the problems is that something truly random may have an infinite range and this range may mean changing type.
    As soon as you limit this there appears to be subtle correllations set up which are not obvious. In a sense this seems to imply that there is only a degree of randomness rather than some absolute.
    If you think of motion representing temperature then 0 degrees(K) is complete determinism and fixed structure , absolute randomness would then correspond to infinite degrees -- what on earth does that mean ??
    The number pi ( 3.14.. ) is completely deterministic yet has a random pattern of numerals ( but far from understood ).
    Now the state of a gas at any instant comprising a few billion atoms is probably as good a random number as any , but how do you generate the number, and the funny thing is you still know the temperature ?? in other words by confining the gas and allowing it to interact with it's surroundings has caused some corellations otherwise the average temperature should be all over the place , and some motions should have infinite velocity.
    True determinism requires 0 degrees K and thus total isolation from any surroundings -- this is virtually impossible -- and there is such a thing as zero point energy , this is the Heisenberg uncertainty principle at work which basically says that if you know with absolute certainty where something is you will not know at the next instant because it will have infinite momentum.
    From a practical view point for most applications there are a huge number of random generators which work very well , electrical atmospheric noise , cosmic rays , timex watches ( only joking) , noise from semiconductor devices such as zener diodes , psuedorandom number generators using shift registers and feedback.
    But all of these have built in corellations which statistically form long term patterns -- a little like saying that 'e' is the most occuring letter in English.
    Some appear to believe that quantum jumps , for example radioactive decay is a completely random event , so that the instant of emission time would be a random number and theoretically of infinite range -- Maybe but how is it that the average is deterministic ( exponential ).
    This is a very tricky but interesting subject -- good luck in your investigations
    Yours Ray.
  5. Nov 20, 2004 #4
    Randomness can be defined in different ways. From the perspective of data processing it can mean incompressible by an algorithm of shorter length than the data. So are the digits of Pi random? In one sense they are, but if you know the trick they aren't.
    Then there is statistical randomness, e.g. there are n different outcomes all with the same probability, or described by a probability distribution.
    Random can mean unpredictable.
    There is a difference between a "random" process and a "random" outcome. A pseudo-random algorithm might just happen to produce data that has a pattern. A deterministic process can produce data that looks random (e.g. the digits of Pi).
    It can mean "having no specific pattern, purpose, or objective.". Something can have a pattern but maybe we don't see it, chaos theory showed patterns that weren't seen before. "having no purpose or objective" gets more philosophical.
    Then there is the meaning 'totally undetermined'. I have doubts that there are truly 'undetermined' events, but I don't know. How can something be shown to be 'undetermined'? Simply us not knowing the cause of something doesn't mean it is uncaused.
  6. Nov 20, 2004 #5
    So if you can have an equation that explains a phenominon(sry for the horrible spelling, i think my pop up blocker is block spell check :( ) then if you put in the exact same variables then would you not get the exact same results. Or is there a random variable in the equation for the phenominon that seems random?

    Ray---lol i think all the watches from target are random, not timex.

    Rachel---(i couldnt help but notice that your opening message for this thread closely resembled the ideas express in your reply to my thread. hopefully i worded things more correctlyish. i know that i may have repeated myself but you said to not hold back. im sry if i made you think, i know from personal experience that it hurts :P)

    Last edited: Nov 20, 2004
  7. Nov 21, 2004 #6


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    Well, for some reason my brain isn't working, so I have nothing constructive to add right now- maybe later. But can anyone define random?
  8. Nov 22, 2004 #7
    random adj. purposeless; haphazard - at random haphazardly
  9. Nov 22, 2004 #8
    Determinism, specifically non-theological determinism dictates a complete cause and effect universe. At any instance, any particle (meaning quark, electron, atom ...) occupies a specific point in space, and has specific velocity (speed and direction). The process is continually interactive in the sense that particles in proximity continually adjust the motion and position of one another. Nothing happens arbitrarily. There is no random. In addition, remember that life, whiich includes humans and the human brain, is made up of particles. -Cee Ann Franklin-
  10. Nov 23, 2004 #9


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    random1 (adj.)- uncaused.
    random2 (adj.)- cause unknown.

    Any objections?
  11. Nov 23, 2004 #10
    Addressing other points already here:
    Pi is not random. Pi is transcendental. Its non-repetion is infinitely precise.
    The Heisenberg Uncertainty Principle is a mathematical consequence. The statistical methods of Quantum Mechanics are mathematical tools which allow us to deal with the complexity of the quantum world. Statistics does not infer the existance of arbitrariness. While it may deal with an abundance of data. behaviours, conditions, and what are termed 'possibilities', the overall results of statistical methods are specific.
    -Cee Ann Franklin-
  12. Nov 23, 2004 #11
    --- replies
    True randomness is not the same as absolute randomness (see below).
    Absolute randomness would be so that you do not see any, at all, connection between what is happening around you, not even that they do not seem to have a connection with each other (our minds may be faulty) nor that there actually is something or that you can see or not. This means you have no abilities of prediction, what so ever.

    "non-theological determinism"?
    If you need to make such a destinction you actually refer to as if our logical system is correct. The existance of a god doesn't neccearily break our logic, unless he has certain features such as holding absolute powers (which are logically contradictionary).
    Therefor, 'determinism as if our logical system was correct, would be ...' (thus excluding meta logic).

    Random in common speech are those referencals which we believe have multiple different outcomes.
    An example would be, will I eat chicken tonight? I am not yet certain, to 100% that that is the case, therefor, it is random, whether or not I will eat it. However, I know that I don't have chicken at home, I will be home late and I don't feel like chicken and therefor, it is unlikely that I will eat it tonight. i.e. random but unpropable.
    Note that this randomness is very much subjective.
    When changing to an objective psuedorandomness, the lack of affecting parameters is what determines whether or not referencals are random or not (which is quite like the case of the human subjective randomness, however, our minds are far from perfect).

    Regarding the more interesting subject, true randomness.
    True randomness (which I only refer to as objective) would be when holding all parameters (except the actual future) but still, a thing has the ability to fall outside the predictions. What this means is that when you arrive at a certain point in time, there is a ranomization regarding the being of those referencals. Basicly, if you could turn back time, going forward to that point multiple times may render you with different results. I do not believe that there is such a thing and the world which we know it, is random.
    I wrote something about this subject in philosophyforums but it doesn't seem to work right now so I can't make the reference.
    -'Hot & cold'
    Predicability (determinibility) and randomness are each other's opposites. However, determinism is a, note, '-ism', saying that nothing is random, if holding all the (possible) data and being better beings, everything could've been predicted, i.e. that randomness is only of the lack of our knowledge (and abilities).
    not "randomness & determinism" but "randomness & determinibility"
    Though, as absolute determinibility is defined (100% determinibility), we have a lower end on the scale (as with kelvin) and don't have to put one on random (as with celsius) as well as a far end of it, being absolute randomness (i.e. 0 determinibility).
  13. Nov 23, 2004 #12
    Cause and effect is the only way a universe can come into existance and continue. Ask yourself this; if there is randomness, what causes it?
  14. Nov 24, 2004 #13
    Anything, for example time, may cause the t. randomness, it is the process of the cause-effect rather than simply the cause which determines whether or not we have a t. randomness.
  15. Nov 24, 2004 #14
    If you say that the zero point is determinism, then it follows that everything moves away from that point as quickly as it can. This may seem random, but it is determined too, by the factors that surround the zero point.

    Random appearance and minute variation in a larger pattern, is the hallmark of life, of organic forms. Determinism is like crystalline growth. Even the lack of pattern in some random seeming organic growth is a pattern of growth, that can be plotted and predicted. The larger patterns planetary rotation, galactic rotation, define what we see. Seems random, but the more we know about the larger patterns, the more determined they become.

    Finally the only thing that can't be explained by determinism, or physics, is the fact that we wonder about this at all.
  16. Nov 24, 2004 #15
    Following your reasoning, I can very well take two cases, one in which I define determinism as the 0 point and in one, where I define randomness as the 0 point, would this then not lead to that in one case, everything moves towards randomness and in one, it moves away. Since I may have this two state definition, are you thus saying, that everything moves away from randomness at the same time as it moves towards it?

    You must bring more support to your notion of this 0 point, 0 point of determinition that is, it is not a 0 point of time.

    All of this is pseudorandomness. We've already pointed out how it is but seemful randomness but thanks for joining the discussion :)

    Actually, there's A lot that cannot be explained by today's science :)
    I'd not say that why we are thinking like this is not something that raises itself above our other unexplored territories or something that ought to be much more complex :)
    I believe in determinism and if we held a form of absolute physics I believe the world could be perfectly be explained and predicted.
  17. Nov 24, 2004 #16
    i have often thought about random things and my conclusion is the same as the one that cen2y posted earlier. to prove randomness you would need to go back in time and observe a Different Outcome than the one from which you came. IF we could do that i believe that is the only way to (dis)prove randomness.

    I dont understand what you guys were talking about when you were comparing randomness to a kelvin thermometer so i will not comment on that
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