1. Cape Town
    Joined
    14 Apr '05
    Moves
    52945
    09 Dec '10 09:00
    Black beetle asked me to try and put my views in writing. Here goes:

    Try to imagine the current point in time as a static state. From here, there is the past and the future. Based on the state of the present, we can calculate using the laws of physics both the past and the future.
    Many of the laws of physics are rather ambiguous as to the arrow of time, but not all are.
    When we calculate the past, from the present, we can usually be fairly sure what happened.
    When we calculate the future however, we are a lot less certain.
    This difference creates the illusion of time.

    However, when you look at the details, especially at the quantum level, we find that the past is not entirely predictable - and this gives rise to the apparent wave nature of quantum particles.
    If we throw away the illusion of time, where we see the past as being existent and having happened and the future as being non-existent and yet to happen, then we should no-longer have a problem with the wave nature of particles. There are many possible pasts and many possible futures. To ask which slit the photon went through is the same as asking which slit it will go through in future. You could say it went through both slits in the past, but you could equally say it will go through both slits in the future. The difference is that when a photon is absorbed you can often narrow down its source to very few possibilities, but when it is emitted, you often have no idea which way it will go.

    Another way of looking at it is that there is a strong bias which makes information flow one way through time much better than the other way. It does go both ways, but the bias is so strong that it seems to only go one way.
  2. Germany
    Joined
    27 Oct '08
    Moves
    3081
    09 Dec '10 11:19
    The thing you should realize about the double slit experiment is that when you try to measure through which slit the particle goes, you are conducting a completely different experiment. The quantum description for "double-slit experiment" is different from "double-slit experiment AND measuring particle in the slit". So you can't really compare the two, especially since the total quantum description for the entire system is unknown and cannot be calculated in practise (it is complex and macroscopic).
  3. Cape Town
    Joined
    14 Apr '05
    Moves
    52945
    09 Dec '10 11:48
    Originally posted by KazetNagorra
    The thing you should realize about the double slit experiment is that when you try to measure through which slit the particle goes, you are conducting a completely different experiment. The quantum description for "double-slit experiment" is different from "double-slit experiment AND measuring particle in the slit". So you can't really compare the two, ...[text shortened]... ire system is unknown and cannot be calculated in practise (it is complex and macroscopic).
    I think I agree with you, but I am not sure where that is relevant to my post.
  4. Standard memberblack beetle
    Black Beastie
    Scheveningen
    Joined
    12 Jun '08
    Moves
    14516
    09 Dec '10 11:55
    Originally posted by twhitehead
    Black beetle asked me to try and put my views in writing. Here goes:

    Try to imagine the current point in time as a static state. From here, there is the past and the future. Based on the state of the present, we can calculate using the laws of physics both the past and the future.
    Many of the laws of physics are rather ambiguous as to the arrow of tim ...[text shortened]... the other way. It does go both ways, but the bias is so strong that it seems to only go one way.
    Well, I don’t believe in the flow of time either, however I have some remarks on your theory: if we accept that time is split into past, present and future, the conception of time loses its coherence because if "the past" is considered to produce "the present" and "the future", the latter two parts would be already included in the past and could not be properly said to have a separate being. On the other hand, if the present and the future are separate from the past, we are forced to assume that their self-contained existence leaves them uncaused, independent and without reference to the past -and this is absurd. Also, since the notions of present and future imply a relation to the past, we have another self-contradiction. So I conclude that neither the present nor the future exist, dew to the fact that neither identity with nor difference from the past is sufficient to establish the reality of the present and future.
    However, although I deny the independent existence of time, I admit the unmediated experience of change is factual; unfortunately I cannot find a coherent way of expressing this experience in terms of the seeming flow of an independent substratum to reality. Since I reject the absolute existence of time and not the existence of the various temporal phenomena, I evaluate as false the hypothesis that time, phenomena and their mutual dependence are independent entities. All in all, since time is flux-in-phenomena and phenomena are merely phenomena-in-flux, time and the things that change are essentially one. Therefore methinks the constant change of things is the sole change over time;



    Edit: “If we throw away… …which way it will go.”

    Since a non-stationary time cannot be experienced and a stationary time which can be experienced does not exist, one can perceive time solely if it is experienced. So I see time as a product of our collective subjectivity that we invented for our convenience, and as such it exists solely in dependence to our own mind.
    However, since the sole thing that takes place for sure is the constant change of the location of the photon in the context of the double-slit experiment, we should be able to spot the exact slit that the photon went through when we observe it. Therefore, even if we assume that the experiment is conducted during a fully observable by us condition of the photon that remain constant over time although it changes throughout space, the fact is that we still have no idea what the exact nature of the quantum particle is
    😵
  5. Germany
    Joined
    27 Oct '08
    Moves
    3081
    09 Dec '10 12:031 edit
    Originally posted by twhitehead
    I think I agree with you, but I am not sure where that is relevant to my post.
    Well, the photon simply always goes through both slits (a.k.a. totally predictable), I don't see where past/future comes in.
  6. Joined
    26 May '08
    Moves
    2120
    09 Dec '10 12:11
    Originally posted by twhitehead
    Black beetle asked me to try and put my views in writing. Here goes:

    Try to imagine the current point in time as a static state. From here, there is the past and the future. Based on the state of the present, we can calculate using the laws of physics both the past and the future.
    Many of the laws of physics are rather ambiguous as to the arrow of tim ...[text shortened]... the other way. It does go both ways, but the bias is so strong that it seems to only go one way.
    “...When we calculate the past, from the present, we can usually be fairly sure what happened.
    When we calculate the future however, we are a lot less certain.
    THIS difference creates the illusion of time. ...”(my emphasis)

    I have probably a bit confused and completely misunderstood what you said here but, as I read that assertion, it surely must be false!
    I mean, suppose that it so happens I am MORE certain of the future than the past? (lets say my memory is a bit poor but my powers of prediction is rather better)
    Wouldn't that mean, according to your assertion, that I would misperceive the past as the future and the future as the past?
    And what if it so happens I am exactly equally certain of the future as the past? Wouldn't that mean, according to your assertion, that I would cease to perceive time!?
  7. Cape Town
    Joined
    14 Apr '05
    Moves
    52945
    09 Dec '10 12:37
    Originally posted by black beetle
    Well, I don’t believe in the flow of time either, however I have some remarks on your theory: if we accept that time is split into past, present and future, the conception of time loses its coherence because if "the past" is considered to produce "the present" and "the future",
    ...
    So I conclude that neither the present nor the future exist, dew to ...[text shortened]... difference from the past is sufficient to establish the reality of the present and future.
    I don't entirely follow you. However, it is my suggestion that you look at the present as existing, and the past and future as existing only insofar as they can be determined from the present.
    Imagine a particle travelling through space. You know its position and velocity. You can calculate both its past and its future trajectory. Neither actually exists. Neither can be said to have 'taken place' or 'will take place'. You can be absolutely certain of neither. The location of the particle in the past or future is described by a probability graph. The only real difference between past and future is that the particles probability graph is fairly well determined on macroscopic scales in the past, and very poorly determined in the future (at any scale).
  8. Cape Town
    Joined
    14 Apr '05
    Moves
    52945
    09 Dec '10 12:39
    Originally posted by KazetNagorra
    Well, the photon simply always goes through both slits (a.k.a. totally predictable), I don't see where past/future comes in.
    And will it go through all possible slits when emitted?
  9. Cape Town
    Joined
    14 Apr '05
    Moves
    52945
    09 Dec '10 12:40
    Originally posted by Andrew Hamilton
    I mean, suppose that it so happens I am MORE certain of the future than the past? (lets say my memory is a bit poor but my powers of prediction is rather better)
    Wouldn't that mean, according to your assertion, that I would misperceive the past as the future and the future as the past?
    Correct. Why do you assert that that "must be false"?
  10. Joined
    26 May '08
    Moves
    2120
    09 Dec '10 12:531 edit
    Originally posted by twhitehead
    Correct. Why do you assert that that "must be false"?
    You confuse me:

    “...Correct....”

    So you agree your assertion was false?

    “...Why do you assert that that "must be false"? ...”

    So does this mean you Disagree your assertion was false?
    I asserted that that assertion "must be false" because I can imagine being exactly equally certain of the future as the past and still perceive time and I see no contradiction between those two things. But I think I must be misunderstanding what you said.
  11. Germany
    Joined
    27 Oct '08
    Moves
    3081
    09 Dec '10 12:55
    Originally posted by twhitehead
    And will it go through all possible slits when emitted?
    Under what conditions specifically?
  12. Standard memberblack beetle
    Black Beastie
    Scheveningen
    Joined
    12 Jun '08
    Moves
    14516
    09 Dec '10 13:05
    Originally posted by twhitehead
    I don't entirely follow you. However, it is my suggestion that you look at the present as existing, and the past and future as existing only insofar as they can be determined from the present.
    Imagine a particle travelling through space. You know its position and velocity. You can calculate both its past and its future trajectory. Neither actually exists ...[text shortened]... on macroscopic scales in the past, and very poorly determined in the future (at any scale).
    But, if I will see the present as really existing the way you think it exists, the past and the future would be by definition non-existent due to the fact that the sole thing that would occur it would be an ever-changing present. Therefore, by definition, the sole change would be the travelling per se through space of the particle you mentioned. In this case its trajectory would be de facto real and orthogonal, otherwise we would not be able to spot at all the change that takes place in the kinetic condition of the particle.
    Therefore, since the constant change of the location of the particle is indeed the sole change that takes place, methinks we should be able to monitor its factual trajectory instead of offering just a probability graph
    😵
  13. Cape Town
    Joined
    14 Apr '05
    Moves
    52945
    09 Dec '10 15:12
    Originally posted by Andrew Hamilton
    So you agree your assertion was false?
    No, I think I agree with your point that better knowledge of the future than the past would lead to the illusion that time was flowing the other way.

    I asserted that that assertion "must be false" because I can imagine being exactly equally certain of the future as the past and still perceive time and I see no contradiction between those two things. But I think I must be misunderstanding what you said.
    Maybe I am asserting that it is the flow of time that is an illusion? Maybe I am asserting that nether the past nor future fully exist?
    What I don't see is how your reverse time flow proves my assertion false.
  14. Cape Town
    Joined
    14 Apr '05
    Moves
    52945
    09 Dec '10 15:17
    Originally posted by KazetNagorra
    Under what conditions specifically?
    I am suggesting that past and future should be viewed in the same way. If you can assert that a received photon traveled all possible paths to its current location, then can I equally assert that an emitted photon will travel all possible paths from its current location.
  15. Cape Town
    Joined
    14 Apr '05
    Moves
    52945
    09 Dec '10 15:23
    Originally posted by black beetle
    But, if I will see the present as really existing the way you think it exists, the past and the future would be by definition non-existent due to the fact that the sole thing that would occur it would be an ever-changing present.
    You are so used to the illusion of time that you are hanging on to it too tight. The present does not change, nor move through time. It just is. There are possible pasts and possible futures, but neither 'exist'.
    When viewed from the present, on the macro scale there is often only one possible past. However there are almost invariably multiple possible futures. This imbalance creates the illusion of time.
    However, when viewed at a much smaller scale, the possible pasts are less well defined.
Back to Top