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Does matter really exist?

  1. Sep 30, 2011 #1
    Hi all,

    I was wondering if anyone is aware of any theories in physics that don't rest on the assumption that matter exists.

    I've heard a few theorists (both particle physicists, string theorists, and mathematicians) describe how it becomes very hard (if not impossible) to describe what an object or a particle really is once you zoom in enough. In other words, the question of whether fundamental particles really exists can become somewhat meaningless as math becomes the only language that correctly describes reality at that level.

    Could it be that the universe only consists of energy? And that matter is thus an illusion?

    I'm sure someone must have theorized about this. Any thoughts?

    Thanks!
     
  2. jcsd
  3. Sep 30, 2011 #2

    gneill

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    If it's an illusion it's a very good one, and I for one believe that I've gotten my money's worth :smile:
     
  4. Sep 30, 2011 #3

    Drakkith

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    Why would matter not exist? We've measured something with an electric charge of -1 with a specific mass that we can interact with, it's labeled as an electron. Does it matter if what it "really" is is different from what we think it is? That wouldn't change any of the properties of it or change the way it interacts. It would still be an electron! I'd say it's a matter of definition rather than what "really" exists or not.
     
  5. Sep 30, 2011 #4
    I agree, I'm not complaining at all. I cherish it just as much as my free will:-)
     
  6. Sep 30, 2011 #5
    I agree it's a matter of definition. Certainly the electron doesn't exist in the same way as laypeople would say that a rock exists. With quantum theory it just becomes very unclear what we mean by existence.

    But my point is more practical than anything. To my understanding, all theoretical developments in physics attempt to remain consistent with the theory of relativity; which explicitly builds on the assumption that matter exists. I'm just wondering if we got rid of that assumption perhaps someone could develop a simpler way to unify the forces we know of.
     
  7. Sep 30, 2011 #6

    Drakkith

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    Why would an electron not exist just like a rock does? Quantum Mechanics is very clear about what exists and what doesn't. Also, different theories describe matter differently but still have to obey current known laws. Changing the definition of matter doesn't change any of that.
     
  8. Sep 30, 2011 #7

    Pengwuino

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    Not at all. When you start getting into QFT, saying something is a particle equivalent in existence to how a rock exists gets sketchy. Throw in GR to the mix and you get all sorts of non-sense that people typically will hand-wave away the explanations for.
     
  9. Sep 30, 2011 #8
    Because of the uncertainty principle.
     
  10. Sep 30, 2011 #9
    I would argue if you are here to ask this question, matter certainly exists in a particular limit.
     
  11. Sep 30, 2011 #10

    DaveC426913

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    Whatever it is we experience when we probe for matter - be that hard little spheres or diaphanous energy fields that merely act like hard little spheres - that is what we call matter.

    It exists because we detect it existing.

    The question I think you are asking is: when we detect matter, are we detecting something physical?

    To which the answer is a question of definitions: what do you mean by "physical"?
     
    Last edited: Sep 30, 2011
  12. Sep 30, 2011 #11

    Drakkith

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    I agree with Dave.
     
  13. Sep 30, 2011 #12
    The illusion of matter( in my understanding ) is similar to the one of a spinning helicopter rudder( looking solid ). But in matter it's the electron, and it "feels solid".
     
  14. Oct 1, 2011 #13
    What do you mean by exist?

    And I've never seen a theory of a physicist which rests on the assumption that matter doesn't exist, but I've not seen one resting on the assumption that it does exist. How exactly would this come into effect in a theory?
     
  15. Oct 1, 2011 #14
    Einstein theorized it. His answer? OF COURSE the universe consists of only energy, and lots of it: Matter is energy, at the rediculous exchange rate of Energy = Matter x C^2

    So the theory your looking for is general relativity. Probably not the answer your looking for, but maybe thinking of it so simply will help you refine your question, or think of great new questions altogether.
     
  16. Oct 1, 2011 #15
    A good question! And one that has been around since ancient times. An Ionian Greek thinker Zeno proposed a number of paradoxes that while taken into consideration may well have predicted our uncertainties of motion and position: http://www.mathpages.com/rr/s3-07/3-07.htm

    The argument goes back to cosmologies. Can we find mathematical rules that decide the universe. Or are they simply descriptions of what we observe.
     
  17. Oct 1, 2011 #16
    I hate to break it to you, but, while Zeno was a great philosopher, most of his great teachings are contradicted by calculus. They didn't know about limits back in the day...
     
  18. Oct 1, 2011 #17

    Dale

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    I have a basic aversion to discussing whether or not "X really exists". IMO it is a completly empty question, scientifically speaking. There is no really-exist-ometer that can test whether or not X "really exists" and the people asking the question never even bother to clarify what they mean by "really exist". At best it is philosophy, and usually it doesn't even rise to that level.

    Theories which admit matter do very well at predicting the results of experiments performed to date. So any theory which doesn't admit matter would have to reduce to the matter theories for all known experimental conditions.
     
  19. Oct 2, 2011 #18
    Exactly.

    I think the only way we could attempt to quantifying what "to exist" means without being self-contradictory or being a vacuous statement is for the definition to be "something that we can interact with" or "detect the effects of" and so on (and there are still some problems to be ironed out here). So in that light, of course matter exists.

    Does energy exist? I'd say yes, that we don't consider it as a "physical" thing, to me, is irrelevant, especially since we can't meaningfully say what is "physical" and what isn't.

    I think a really thought provoking question is "does the past exist?". Is it meaningful to say that one past exists any more than a different past which would lead to the same present? It seems not. You are then lead on to thinking, is it meaningful to say that any particular present is more "real" than another one for which we can't detect the difference? (this question can't really be separated from the above since we now know there is not actually any meaning to "the present" or "the past"). The "does a tree fall in the woods make a sound if no one hears it?" question sounds less silly than at first.


    ...
    And look what's happened. I've lead myself down a horrid trail of useless philosophy. That's why you can't implement these sorts of things into a useful scientific theory!!!
     
  20. Oct 2, 2011 #19
    Thanks for the opportunity to clarify, calculus has nothing to do with the validity of the paradoxes. Using limits means we are assuming continuity and thus infinite divisibility, exactly what Zeno paradoxes are about. So, it tells us to look at his continuous motion paradoxes [the dichotomy, achilies and the tortoise] rather than the discrete paradoxes [the stade, the arrow].
     
  21. Oct 2, 2011 #20
    But Zeno implicitly uses continuity for his paradoxes by insisting that we can always look at half the distance between things.

    To be honest, you don't really need limits to see the paradox in Zeno's paradoxes- his paradoxes work by insisting something which isn't true, namely that an infinite sum must be infinite (although there are other ways of looking at it).
     
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