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

B New Theory vs New Force/Field of nature

  1. Oct 20, 2017 #1
    Hi,

    How do you differentiate between fields from a new theory or new fundamental forces? For example. If QM is replaced with a new theory, would the extra dynamics and degrees of freedoms be new forces of nature or can they be non-force or field related, can you give some examples to differentiate? For example. The Higgs field is not a new fundamental force.. is it because Higgs didn't come from some kind of gauge symmetry? How about the new theory that might someday replace quantum mechanics.. what other Higgs like field do we have that are different from the 4 fundamental forces yet is not a new force/field of nature?

    Reading the following led me to wonder:

    "I think what will happen is eventually quantum mechanics will need to be replaced, and the new theory might ascribe more obviously to one of the current interpretations, even if it also introduces some new ones. If so, then it will be useful to be versed in all the interpretations, because we never know which one will be the most conducive to the development of the new theory. We saw this with classical mechanics, where the Hamiltonian formulation is more conducive to quantum mechanics and the Lagrangian formulation is more conducive to quantum field theory. Ironically, often overlooked is the fact that the interpretation of the existence of "forces" is not particularly conducive to either! Yet we prefer that interpretation so much that we still teach it in high schools, which goes to show you that perhaps we should not be interpreting our interpretations as "what is really happening" anyway!"
    Reference https://www.physicsforums.com/threads/entanglement-what-is-it.927145/page-4
     
  2. jcsd
  3. Oct 21, 2017 #2

    Demystifier

    User Avatar
    Science Advisor

    Why do you think that Higgs is not a force? Other particles interact by exchanging virtual Higgs particles, so it is not less a force than electroweak or strong interaction.
     
  4. Oct 21, 2017 #3

    mfb

    User Avatar
    2017 Award

    Staff: Mentor

    You are mixing different concepts.

    A new theory might add extra fields within the existing framework of quantum field theory. Basically all proposed theories are doing this. Everything new adds new fields. "Force" is not always a well-defined concept here, and depends on what exactly you want to call force. Some new fields would certainly behave like the classical forces, some would not.

    It is not impossible that quantum field theory itself gets replaced by something else, although it is hard to imagine how. This could change the whole concept of fields and particles.
     
  5. Oct 21, 2017 #4
    I used the word "force" for familiarity because we often heard about the four fundamental forces of nature.. but we could now use the more accurate description "the four fundamental field of nature".

    Why is Higgs field not considered as the 5th fundamental field of nature?

    Higgs field comes from Yukawa interaction and not from gauge interaction.

    Does this mean a 5th fundamental field of nature must only be called such if it is a gauge interaction?
     
  6. Oct 21, 2017 #5

    mfb

    User Avatar
    2017 Award

    Staff: Mentor

    There are way more than 4, even if you look at bosonic fields only. But then you can make 2-5 groups out of them. The large range shows how arbitrary these groups are.
     
  7. Oct 21, 2017 #6
    So that's why it's not called the "four fundamental field of nature", because there are many fields...

    Bosonic fields composed of:

    spin 0 higgs boson
    spin 1 electroweak bosons or the W+, W-, Z0, Photon
    spin 2 graviton

    There are already 5.. and the fermionic fields add more fields..
    So maybe we should stick to "four fundamental force of nature".. but then QFT says there is no force and this belonged to the days of faradays. So maybe we should use "four fundamental field of nature"? or "four fundamental bosonic field of nature"?

    This is just for accuracy when conveying to laymen and other physicists.

    Since we don't refer to Higgs as the 5th fundamental force or field.. does it mean for other new field that would be discovered (for example that can bind matter and dark matter).. we can't refer it as the 5th fundamental force or field?
     
  8. Oct 21, 2017 #7
    the concept of force varies, a theory can never be replaced only increase more and more.a classic example but one that confuses many people and gravity, people think that gravitation was replaced by general relativity but not well, so relativity does not it says that gravitation is wrong, no, it only delimits to where gravitation is applicable. This is only an example of how difficult it is to think that the theory of quantum mechanics is going to be replaced, since the concept of forces varies from each theory.
     
  9. Oct 21, 2017 #8

    Demystifier

    User Avatar
    Science Advisor

    Would you count string theory as "something else"?
     
  10. Oct 21, 2017 #9
    Maybe for accuracy, we must only refer to the 5th force if it is related to gauge symmetry like SU(3)xSU(2)xU1 of the standard model or the symmetry group of general relativity.

    So if the proton radius problem is due to an undiscovered force or field.. maybe it's not really a fundamental force.. because some use headlines connecting it to a new fundamental force or field.

    So if SU(3)xSU(2)xU1 of the Standard model is just a subgroup of a larger group. Then that higher symmetry group should produce more fundamental force or field.

    Also we want to seek higher symmetry by higher energy and temperature. But if the gauge group was produced from a low energy phase transition.. then it should be considered as 5th fundamental force too.. is it not.. as long as it should be able to affect the fundamental forces (any reference or papers regarding low energy phase transition?)
     
  11. Oct 21, 2017 #10

    mfb

    User Avatar
    2017 Award

    Staff: Mentor

    It is still based on quantum field theory.

    @star apple: You forgot the gluons.
     
  12. Oct 21, 2017 #11
    When presented with a new experimental data stream... how do you recognize whether it is:

    1. A new object like strings or branes (or dark matter) where you apply our trusted quantum field theory
    2. A new particle like the supersymmetric particle or 4th generational particles
    3. An enhanced QFT or quantum theory the will change the whole concepts of of particles or fields.
    4. An enhanced QFT or quantum theory where you still use particles or fields but with quantum potential for example
    5. A new fundamental gauge symmetry field like the electroweak bosons (local)
    6. A non gauge symmetry field like the higgs field or new informational field that doesn't behave like spin 0, 1 or 2 (local) (Are there fields that don't have any intrinsic spins?)
    7. A new gauge or non-gauge symmetry field (non-local).
    8. A new set of manifolds underlying spacetime (perhaps LQG atoms of space)
    9. Somewhere altogether different from spacetime or quantum field theory where these two are but emergence.
    10. A hidden low energy sector phase transition to higher symmetry state.
    11. what else?

    Is there a complete lists written in an article by any physicist? When hit with a stream of BSM data.. how do you tell which is which (or how do you recognize which)? Any step by step tests to recognize what it is?
     
  13. Oct 21, 2017 #12

    mfb

    User Avatar
    2017 Award

    Staff: Mentor

    That's not how it works, and I fear you don't have the required knowledge to understand why these questions don't make sense.
     
  14. Oct 21, 2017 #13
    How does it work and why these questions don't make sense.. please explain.. assume you can't prepare or control the experiments like in LHC. It just comes to you out of the blue outside of the lab..
     
  15. Oct 21, 2017 #14

    Drakkith

    User Avatar
    Staff Emeritus
    Science Advisor

    What? That's just not how science works at all.
     
  16. Oct 21, 2017 #15
    But is it not if something is part of the Beyond Standard Model in the lab.. it means it is part of nature.. so it is all around us.. this is specially so if there occurs low energy phase transition to higher symmetry state. That means you don't need the LHC high energy to aim at small space. If I'm wrong. please tell me why low energy phase transition is not possible.
     
  17. Oct 21, 2017 #16

    Drakkith

    User Avatar
    Staff Emeritus
    Science Advisor

    I'm sorry but I don't understand what you're trying to say. Could you elaborate?
     
  18. Oct 21, 2017 #17
    Usually higher symmetry state is related to high temperature after the big bang where the Su(3)xSu(2)xU(1) was subset of say the Su(5) Gut or even the E8. After temperature went down..effect was like phase transition from liquid to ice (this is my context of the words phase transition.. of course i heard it described often.. But the Su(5) product has more parameters and proton was not shown to decay. Could it be possible the symmetry Su(3)xSu(2)xU(1) (or portions thereof since electroweak was proven to be related to high energy and high temperature) was subset of another symmetry state in the low energy sector much below the GUT or even the electroweak sector. Its jus hidden. Who are the physicists who have suggested this and status of their suggestions at this point in time.
     
    Last edited by a moderator: Oct 21, 2017
  19. Oct 21, 2017 #18

    Demystifier

    User Avatar
    Science Advisor

    You mean 2-dimensional conformal QFT? OK, that's perturbative string theory. But how about non-perturbative string theory, such as M-theory? Nobody knows what M-theory really is, but many seem to think that it cannot be reduced to QFT (except in some limits, of course).
     
  20. Oct 22, 2017 #19

    mfb

    User Avatar
    2017 Award

    Staff: Mentor

    @Demystifier: I count extensions of QFT as "based on QFT", but I think we should keep this thread at B-level.


    @star apple: Your posts don't make sense, and you are trying to understand advanced concepts without learning the basics first. That won't work.
     
  21. Oct 22, 2017 #20
    There was an article in the IEEE peer reviewed journal about electromagnetism being possibly Su(2) instead of partial U(1). The author proposed symmetry in electrodynamics where there is magnetic monopoles in addition to electric poles to complete an electromagnetism symmetry. Ill get the full article tomorrow..i didnt make up any of what im saying.
     
  22. Oct 22, 2017 #21
    See this https://www.researchgate.net/public..._by_amended_Maxwell_theory_and_author's_reply

    The strong force has just very few parameter like the coupling constant g and quarks masses. but electroweak has many including some believed as not so pretty or completely symmetric.. could some symmetry fixing within it can lessen the parameters like in QCD?
     
    Last edited by a moderator: Oct 22, 2017
  23. Oct 22, 2017 #22
    Demystifier and mfb. In the layman book "Elegant Universe" by Brian Greene. He went into details about the perturbative methods vs the nonperturbative string theory like M-theory so asking about perturbative vs nonperturbative method is part of the beginner questions (as Brian Greene book is for beginner). The following is sample of paragraphs where the words "nonpertubative" is mentioned:

    "Nature is telling us emphatically that under such conditions we must merge general relativity and quantum mechanics - in other words, we must make use of string theory. Currently, research on the implications of string theory for cosmology is at an early stage of development. Perturbative methods can, at best, give skeletal insights, since the extremes of energy, temperature, and density require precision analysis. Although the second superstring revolution has provided some nonperturbative techniques, it will be some time before they had honed for the kinds of calculations required in a cosmology setting. Nevertheless, as we have discussed, during the last decade or so, physicists have taken the first steps toward understanding string cosmology."
    <snip>
    "The developments discussed in this and the previous sections represent the first, somewhat tentative steps toward understanding the cosmological implications of string/M-theory. During the coming years, as the nonperturbative tools of string/M-theory are sharpened, physicists anticipate that some of hte most profound insights will emerge from their application to cosmological questions." [The Elegant Universe by Brian Greene]

    Just like nonperturbative string theory like M-theory can give more accuracy. What if there was no strings (meaning superstrings theory not true) and our QFT is made non-perturbative QFT.. what would be the extra degree of freedom produced? Like could it produce a new force/field of nature or a new non-gauge field?
     
  24. Oct 24, 2017 #23
    Maybe what I meant to ask was, if we have a new quantum theory (not just intepretation), this means either trajectories were detected as in BM or Objective Collapse proven.. does it affect high energy physics too? Because Schrodinger quantum mechanics is just approximation to Quantum Field theory.. and our QFT is approximation to nonperturbative QFT, and so on.. and you also have quantum gravity. So if there is a new quantum theory.. would it only affect low energy or below the electroweak scale or even affect (or be relevant) as high as the GUT or planck scale?
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook