Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The Unity of the Dualities? Wave/Partice Duality, Space/Time Duality, and Energy/Mass

  1. Jan 7, 2007 #1
    Does any theory explain all these dualities:

    Wave/Particle Duality, Space/Time Duality, and Energy/Mass Duality.

    Does ST or LQG account for all these dualities?

    What I mean is, can ST or LQG show that these dualities are unified by some deeper physical model?

    Can any theory show that all the dualities arise from a common physical reality?

    Last edited: Jan 7, 2007
  2. jcsd
  3. Jan 8, 2007 #2
    Well wave/particle duality is just QM. space/time and energy/mass are just special relativity. So the answer is, a theory that has all these features is ordinary qft.
  4. Jan 8, 2007 #3
    Yes, perhaps.

    But what is the underlying physical reality?

    Can I picture it?

    If QFT has both wave/particle duality and space/time duality, does it not then unify QM and SR?

    But back to the original question--what is the physical model that unifies all the dualities on a physical level.

    Saying "QFT does it--move along now," does not quite seem satisfactory.

  5. Jan 8, 2007 #4
    Wave/Particle Duality & Space/Time Duality

    Has wave/particle duality ever been incorporated with space/time duality?

    Do they arise from the same underlying physical reality?

    Can they?

    If so, what would this be?

    For instance, quantum mechanics implies non-locality. And too, two photon's that originate from a single point and travel in opposite directions, stay in the exact same place in time. In fact, each travels an interval defined by the null vector. So it seems that even though they are far apart in our reference frame, in tehir own, they are yet in the exact same place. So it would make sense that they are entagled on a quantum level.

    Has wave/particle duality ever been incorporated with space/time duality?

    Albert Einstein (1924) said: There are therefore now two theories of light, both indispensable, and - as one must admit today in spite of twenty years of tremendous effort on the part of theoretical physicists - without any logical connections.

    What is the logical connection between light as a wave and light as a particle?
    Last edited: Jan 8, 2007
  6. Jan 8, 2007 #5
    Yeah, sorry my original answer was a little trite. I was just trying to answer the question "Does any theory explain all these dualities". I thought you might be surprised to know that you don't have to go to anything so exotic as lqg or string theory to do this. QFT does unify QM and SR.

    As for underlying physical reality (or "ontology" if you want to impress your philosophy prof), you run into problems that many people in interpretations and philosophy of physics have torn their hair out about. See this link for an intro: http://plato.stanford.edu/entries/quantum-field-theory/
  7. Jan 8, 2007 #6
    But does QFT say that wave/particale duality and space/time duality and mass/engery duality arise from the same physical reality?

    If so, what is the postulate? What is the premise?

    Fo instance, Einstein's two postules show that space/time duality and mass/engery duality arise from the same physical reality.

    What is QFT's postulate that shows that wave/particale duality and space/time duality and mass/engery duality arise from the same physical reality?

  8. Jan 8, 2007 #7


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    I don't think anyone here can answer your question, because no one here knows what "underlying physical reality" really means. It's a nonsense term.

    Scientific theories are selected because they allow us to predict the results of experiments. They aren't chosen because they somehow mirror some "underlying physical reality." Many phenomena, such as signal propagation through filters, are very well described by mathematical machinery (e.g. phasors in the complex plane) that certainly does not exist in the physical world.

    So what? After all, we can't actually see or grab hold of electrons -- all we can do is deduce their nature by how they interact with things in carefully designed experiments. Physics does not concern itself with the phiosophy of what an electron really is, since it's very likely that that question has no meaningful answer. Instead, we simply try to find models which predict the outcomes of experiments. Physicists have been rather successful so far in this endeavor.

    - Warren
    Last edited: Jan 8, 2007
  9. Jan 8, 2007 #8


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Admin note: I have moved this thread to the Philosophy of Science, Math, Logic forum, since it seems to deal entirely with a philosophical question.

    - Warren
  10. Jan 8, 2007 #9
    Actually, physics is the study of physical reality
  11. Jan 8, 2007 #10
    Not yet. Even the Standard Model is being revised as stars exceed speeds that should cause them to burn off.
    It might be possible that with wave/particle function that the environment determines the state.
  12. Jan 8, 2007 #11
    If I had to come up with one postulate that did what you describe, probably it would be:
    Each type of particle corresponds to an irreducible representation of the Poincare group.

    The Poincare group is also the group that underlies space/time duality and energy/mass duality. So maybe this is the type of thing you are looking for?
  13. Jan 8, 2007 #12


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Only in the sense that we try to create theories which accurately predict the outcomes of experiments. There's no reason for the models themselves to resemble "physical reality" in any way at all. As I've said, what do we know about the physical reality of electrons, beyond what they do in experiments? We can't see them or touch them, so our human-scale notion of "physical reality" is meaningless.

    - Warren
  14. Jan 8, 2007 #13
    I like your answer. Myself, I sometimes think that when I dream or imagine something, what are its' physical limits ? In reality, my dream or imagination. And yet what defines our physical reality ? Mathematics ?
    To answer poincare and wave/particle duality.
    An electron may be a solid in the absence of other energies(free radical), but when present in a specific field of weak or strong nuclear potential, its' attributes may be relative to its' environment.
  15. Jan 8, 2007 #14
    Mkay first up ill just say a few things about what you said, and if im wrong please others correct me. According to particle physics, which as far as i know, is the prevailing model for explaining physical phenomenon, says that light is a particle, the photon, which is the force carrier for the EM fields. (the photon being a discrete packet of wave energy)

    Furthermore, ive never heard the space-time relationship described as 'duality' and as such am skeptical of its use. Its not so much duality in the way that people think of wave particle duality as much as the two being inescapably woven together, rather than being two seperate observed states. Space and time are linked by, for example, the equations of special relativity and Lortenz transformations, which show that as space is affected by speed (and in GR, gravity) so time is warped in a similar manner, thus they both move and are distorted together as a pair.

    Hope this helps
  16. Jan 9, 2007 #15


    User Avatar
    Science Advisor
    2018 Award

  17. Jan 9, 2007 #16
    What is space time duality ? Where does it apply in QM ?

    In the exact same place ? How can you say that about photons which respect the uncertainty principle ?

    The null vector ?

    QM is just ONE theory, the duality does not mean that there are TWO versions of QM.

  18. Jan 9, 2007 #17


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Admin note: two threads on the same topic have been merged here.

    - Warren
  19. Jan 26, 2007 #18
    Last edited: Jan 26, 2007
  20. Jan 26, 2007 #19
    I like your response.

Share this great discussion with others via Reddit, Google+, Twitter, or Facebook