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Knowledge of everything

  1. Oct 23, 2005 #1
    Is it possible to know everything?

    If it is possible, then is it dependent on time? that is, for a defined moment in time (say a second), one person can know all that there is to know about the universe. since the universe is constantly changing, the future state cannot be stated definitely and one person cannot know what comes next in the future.

    In answer to my original question, I would assume no. My logic (which I feel has error) rests on the fact that in order to know everything, you must know with certainty that you know everything you don't know in order to make the comparison of how much you know. this is a paradox, therefore it is impossible.
  2. jcsd
  3. Oct 23, 2005 #2
    In terms of bits of information, we should be able to determine mathematically the total bits of information predicted in the universe from all possible interactions of the initial matter at time = 0--and recall, although the universe does change over time, if the big bang hypothesis holds, the universal total bits of information must remain a constant, with the bits only changing between matter and energy over time. Now, perhaps we also have models from neural biology that predict the total bits of information that a single human brain on average can hold. Then if the latter can hold the former, then the answer to your question would be, yes, a human could in theory have complete knowledge of everything in the universe, even that which it does not at this time know, but at some future time may come to know--, if the answer is no, then not. Here I use a definition of knowledge that is constrained to the facts and laws of matter plus energy = existence, as the basis of existence that can be known, and that the only way to "know" anything is by application of science, which by definition = "to know" (Webster). As I have stated before on another thread, if 100 % of what you hold to be true is from belief (e.g., not via science), then, by definition, you have 0.0% knowledge of that which in reality is true. Here I equate mathematical knowledge as a subset of scientific knowledge, but I would be open to other views.
  4. Oct 23, 2005 #3
    If one wishes to know the position of the cue ball on a billiard table, one needs to specify this with infinite precision. Anythng less than infinite precision will eventually result in error when trying to predict possible trajectories (chaos theory). Given that each decimal place requires finite time and space to specify, to specify any position with infinite precision is not possible in a universe which is finite in either space or time.

    So far we have only tried to specify the position of the cueball and found this impossible - and now we also need to know "everything"?

  5. Oct 23, 2005 #4


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    Sounds like a similar question as to whether a "true" theory of everything is possible. The 'true' meaning that you obtain the knowledge needed to solve all scientific, philosophic and religious questions. I'd believe we can approach such answers by increasing our knowledge, but our best answers always only saturate near/towards the 'knowledge of everything'.
  6. Oct 23, 2005 #5
    Absolute and objective truth can never be achieved.
    In the final analysis, we are always a part of the universe we are trying to measure. This means that our perspective will always colour the "truth" that we perceive.
    Put into scientific terms : There is an epistemic horizon, characterised by the Heisenberg Uncertainty Principle, beyond which we can never see. Ultimate objective truth can always be pursued, but never reached.

  7. Oct 24, 2005 #6
    Is it possible to know everything?
    The same mind that is 'home to' ('creates' via concept, perception, memory, etc...) that which is being studied, is also formulating new things to study (as it has formulated the previous items for study); new problems to solve, as that is what the mind does; creates 'problems' (the 'material' universe)and 'solves' them (tries to understand it).

    The only universe you can 'know' is the one within your mind, and you can never know if there exists any actual 'in itself' thing in front of your nose! I see it working as an ever-spiral; imagining new 'particles' to discover, and then, lo and behold, discovering them; as an ever expanding dream.. Hence the 'consciousness' of the experimenter being integral within the experiment.

    So, 'Knowing' anything, in an absolute sense is not even possible, but knowing everything?
    One cannot ultimately know everything if one cannot ultimately, absolutely 'know' anything!
    All else is vanity...
  8. Oct 26, 2005 #7


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    You may notice that this thread has been pruned significantly. Please, let's try to keep the discussion at a high level of philosophical merit.
  9. Oct 28, 2005 #8


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    The only knowing everything
    is understanding all at once

    that the everpresent impermanence(creation)
    is all there is.

    Don't throw books at me.

  10. Nov 5, 2005 #9
    ? No philosophy defines "knowing" as "understanding all at once". And by what logic do you conclude that "creation" is impermanent ? It may be true, but logically it also may not be true, e.g., creation may last for infinity.
  11. Nov 5, 2005 #10


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    This highlights an important distinction between Newton's deterministic universe and Heisenberg's "Uncertain" universe.

    In Newton's universe it is, at least in principle, possible to know the position and direction of every atom (and photon) to be arbitrary degree of accuracy. Knowing this means you also know every moment in the past and every moment in the future (a la a billiards shot writ large).

    HUP asserts that, even in principle, it is impossible to know everything.
  12. Nov 6, 2005 #11
    Except, of course, that to accomplish this we would need to know the position and direction of every atom (and photon) not only to an arbitrary degree of accuarcy, but to an infinite degree of accuracy. It would be impossible (even in principle) to encode this information within the universe, thus it would be impossible (in principle) to "know every moment in the past and every moment in the future", even without resorting to HUP. Chaos alone (in the absence of HUP) is enough to make the entire Newtonian spacetime "unknowable in principle"

  13. Nov 6, 2005 #12


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    I would say 'impossible in practice, though not in principle'. I know of no rule that says explicitly that it can't be encoded. (perhaps with some really good lossless compression).

    On the other hand, HUP says explicitly, and in principle, that this level of knowledge cannot be achieved.
  14. Nov 6, 2005 #13
    Assuming Newtonian physics :
    To encode the position and velocity of one electron at one point in time, you would need at least 6 real numbers. Not 6 integers - 6 real numbers (one each for X, Y, Z coordinates, one each for dX, dY, dZ components of velocity). This probably would not be enough information, but let's stick with these 6 real numbers for the electron. The same needs to be done for every other electron and every other particle in the universe. Where are you going to store that information? If there are (sheer guess here) 10^120 particles in the universe you need to store 6 x 10^120 real numbers using those same particles...... it's impossible in principle (there is not enough storage space).

    Compression can only be applied where there is redundancy in information. We have no reason to believe that there is any redundancy in any of the 6 real numbers required for each particle - or do you know otherwise?

    Even if you could reduce all of the information required to just one real number, it still couldn't be stored. There is not enough storage space in a finite universe to store a complete real number. Unless you want to propose that all the information needed for the entire universe could be reduced to a single integer?

    Last edited: Nov 6, 2005
  15. Nov 6, 2005 #14


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    Look at your post.

    Do you see how logic(thought)
    about the non-existant is
    all false?
  16. Nov 6, 2005 #15


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    For example, you use the
    word "conclude"...that word implies permanence.

    Permanence does not exist.

    All philosophy is nonsense.
  17. Nov 6, 2005 #16


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    I question your logic about compressibility.

    One example of compression where there is no redundancy:
    Two particles in space require those six coordinates to X decimal places of precision. That does not mean you need six numbers with X decimal places of precision. Recording merely the DELTA of the second particle (wrt the first) requires a way smaller number.

    Whether or not that's sufficient compression to overcime storage restrictions isn't the point. The point is, I've performed an arbitrary amount of compression without losing any data.

    Now, the overarching point here is this:

    We could discuss back and forth whether it's possible or not possible to record the info, but no matter which one of us appears to have the last word on the subject, it is always possible that there is something more to add ("Eureka, I came up with a better compression algorithm!") after a week, or a century.

    But there is no explicit, in principle, reason why it can't be done.

    Whereas HUP says there is.
  18. Nov 6, 2005 #17
    In fact this IS an example exploiting redundancy - if indeed the absolute positions of the particles is redundant information (as your example assumes). We can only dispense with the absolute positions and work just with deltas if the absolute position information is redundant.

    With 10^120 particles, talking deltas simply reduces the number of real numbers to 6 x ((10^120) - 1). Not much of a saving!

    In fact no saving at all when you remember that we are dealing with infinite precision reals - and (infinity - X) = (infinity)

    You have not compressed anything. (infinity - X) = (infinity)
    You still need an infinite storage space to store a real number - even if you could reduce all 6 x 10^120 reals to one real. Unless you can compress the real number to an integer? Are you claiming this?

    Now the overarching point here is: There is in principle no way to compress an infinite real number to an integer. And that will never change. Period.

  19. Nov 7, 2005 #18


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    We are not dealing with infinities - that is a straw man. Restate your case without them. (BTW, no one - except you - said anything about integers either.)

    It is not necessary to record values to an infinite level of precision. It is only necessary to record them to an arbitrary level of precision. 'Arbitrary', in this case, being defined as "high enough to enable extrapolation of all future and all past trajectories and interactions".

    Again, impossible in practice, but not in principle.

    And again, as remains the case, debatable.

    Whereas, HUP (granting that it holds true), is not debatable, as it states the principle explicitly.
  20. Nov 7, 2005 #19
    No straw man. Try to specify an arbitrary real number EXACTLY by using integers. It cannot be done - in principle (not just in practice).

    Are you suggesting that you would use real numbers, and not integers, to store the data?

    "all future" would be an infinite level of precision, not simply an arbitrary level of precision. Use any combination of integers you wish to store this and eventually the prediction will be in error.

    Would you care to say "what" level of integer precision you would need?
    No, I guessed not. Because whatever level of precision you choose, it will result (eventually) in an inaccurate prediction (if we try to predict far enough ahead). The only level of precision that will "always" give an accurate prediction is an infinite level of precision.

    That HUP places a limit to our epistemic abilities is not in question - no need to keep repeating yourself here

  21. Nov 7, 2005 #20


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    You are too quick on the draw with your comebacks. You are falling farther and farther off the mark. Nobody is saying "infinite", nobody is saying "exactly", and nobody is saying "integer".

    Or let me rephrase: you do not need to specify a coordinate exactly, or with infinite precision, nor using an integer. You need merely specify it to a level of precision that is good enough to get the job done.

    Until you're back on track, there's little point in addressing the rest of your comments.
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