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Are space and time definable without atoms?

  1. Mar 25, 2009 #1

    ConradDJ

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    Atoms are remarkable little creatures. Not only are they generally very stable, but they fit together to make molecules, in which the distances and angles between nuclei are fixed quite precisely (subject to quantum fluctuation). So you can make measuring-rods out of them, among other things. And they also work as very precise clocks, keeping time by the orbital frequencies of their electrons, etc. And they communicate with each other – mainly through electromagnetic channels, but also (rarely) through exchange of nuclear particles like neutrinos.

    Off hand, it seems that apart from atoms (and things made of atoms), physics describes nothing that can function at all like this. An atomic nucleus by itself may have a certain definite size, but you can’t make any kind of stable spatial configuration with a bunch of nuclei, so you can’t use them to measure distances. An electron by itself may have a certain frequency, but you can’t use it as a clock, because as soon as you interact with it you change its frequency. In general, particles interact with each other and transfer various kinds of information, like momentum and spin-orientation. But an atom can store several different kinds of information at once, and can change its state in multiple ways, while maintaining a stable identify over billions of years. The heavy nucleus of the atom allows its location to be defined very exactly, while the surrounding shell-structure of its electron cloud lets it interact very sensitively to its electromagnetic environment.

    I’m not clear exactly how to define the “functionality” of atoms, because it’s complex and multifaceted. But it does seem that the emergence of atoms represents a very large step in the evolution of our universe, considered as a system for defining and communicating information. Before there were atoms, I’m wondering whether space and time would have been meaningfully definable?

    Of course we can just posit a spacetime continuum (or whatever) as a mathematical structure, along with mathematical laws of dynamics, etc. But maybe our ability to define something logically is less significant than the ability of the physical world to define itself concretely, in actual measurements.

    We know the universe we live in is extremely “finely tuned” in its basic parameters. My impression is that changing almost any of these parameters, in some cases by a very small fraction, would make the existence of stable atoms impossible – or at least atoms built the way ours are.

    I’m not interested in “anthropic” reasoning – the idea that the world has to be the way it is, or we wouldn’t be here to observe it. The existence of conscious observers seems to depend on a lot more than just laws of physics, and it hardly seems central to the way the physical world itself operates. On the other hand, maybe there’s a way of making sense of a universe that’s structured to support the existence of atoms, i.e. entities that are capable of defining that same structure, to each other.

    So when it comes to foundations of physics, I’m wondering whether the key really will turn out to be defining spacetime structure at the Planck scale, so many orders of magnitude beneath the atomic level. Is it likely that a quantum gravity theory will explain why atoms exist?... i.e. why the laws of physics produce tiny, finely-tuned devices for measuring and communicating information?
     
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  3. Mar 25, 2009 #2

    ZapperZ

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    Is there a reason why a question that is on physics is being asked in the philosophy forum?

    Zz.
     
  4. Mar 25, 2009 #3
    Maybe it's in the Philosophy forum because the question is not currently answerable conclusively. BTW, IMO this forum should be called "Philosophy of science" as mere philosophy is nothing but logical speculation(often baseless and wrong).

    If String Theory turns out to be right, space and matter are both different manifestations of the vibrating strings that make up everything in the visible universe. To make matters worse, ST(all 5 versions) come up with a prediction of a universe based on the holographic principle. Take this with a grain of salt(and most other cutting edge theories) because ST is currently at an impasse, one of the leading string theories said on one of the annual ST meetings - "We don't know what we are talking about":


    "Science has reached an enormous impasse. From biology to physics, astronomy to genetics, the scientific community is reaching the limits of understanding which often presage a complete rethinking of long-accepted theories. So characteristic of this new apex of modern arrogance is the inability to comprehend the obvious in physics: That we don’t know what we are talking about."


    More:

    http://www.articlesworld.com/we-dont-know-what-we-are-talking-about-nobel-laureate-david-gross/


    Your OP question is not much different than "Is the universe finite or infinite?". I don't think anyone is entitled to answer this. There is no agreement among cosmologists either.
     
    Last edited: Mar 25, 2009
  5. Mar 25, 2009 #4

    DaveC426913

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    Well, space and time existed when the universe was still too hot to let atoms form, so...

    yeah.
     
  6. Mar 25, 2009 #5

    disregardthat

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    Space and time are human concepts. Without atoms, conscious beings wouldn't exist, and thus no one would be there to define these concepts.
     
  7. Mar 25, 2009 #6

    DaveC426913

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    Ok, again with this "human concepts" thing... :grumpy:

    Dinosaurs and rocks certainly made very effective use of both space and time long before humans came along to "conceive" of them.
     
  8. Mar 25, 2009 #7

    apeiron

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    The particular "shape" or bundle of properties that is an atom would not seem to be predictable from even a complete knowledge of the micro-realm of the planck scale. These would be emergent facts.

    But all is not lost if you can instead predict what will emerge from a top-down, system-level, perspective.

    So to use an extreme example, the Platonic forms are the only possible completely regular solids. This was used to make the top-down argument that atoms must take the shape of these platonic solids.

    And we still kind of do that in thinking of particles as little balls (Newtonian modelling).

    And we are now trying to do that in a very sophisticated way with gauge symmetry. SU1/2/3 etc. These model base-line resonances. So they would be the lowest modes that "particle-ness" would fall into. They would give us the shape of what must exist as located particles. And then the properties endowed would allow these particles to construct the atoms we see.

    So if this gauge symmetry project pans out, then we would have a sufficiently good TOE to predict the shape and existence of atoms from first principles - but from the top-down.

    Gauge symmetry is a beautiful idea. But as an aside, I believe progress is being hampered by the requirement that all the different broken symmetries fold back (unify) to some single larger symmetry.

    That is, there is a need for the beginning to be a single crisp origin point. But as I say, banging on about vagueness again, it may work better if these (broken) symmetries are themselves seen to emerge (top-down). So increasing (broken) symmetries swim into view as the effective number of dimensions is diminished.

    We know that lie symmetries become sporadic as dimensionality is raised - their appearance increasingly spotty and random. This seems baffling for those expecting a crisp unification at higher dimensionality. But take a different emergence based view, and tight, nested, (breakable) symmetries would only start to appear towards the end of the trail, once dimensionality has been reduced right down to, say, 11, 10 and even fewer dimensions.
     
    Last edited: Mar 25, 2009
  9. Mar 25, 2009 #8

    ZapperZ

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    So relegating it to philosophy will solve this problem or is better? Anyone looked into the hundreds of pages of discussion on the definition of "exist" in here lately?

    If the question can't be "currently answerable conclusively" (and that's a BIG "IF"), asking it here simply is an indirect license to ignore physical basis and simply make things up as one goes along. Everybody can jump in!

    Zz.
     
  10. Mar 26, 2009 #9

    ConradDJ

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    Just my inexperience with these forums, maybe. Or because reaching for a functional understanding of atomic structure seems pretty distant from established physics. Shall I try again in "Beyond the Standard Model?"

    Right... we can assume that things "really exist" whether or not they're physically definable. That's reasonable, but maybe not in tune with quantum physics, depending on how you interpret it.

    Maybe we could imagine spacetime structure in the pre-atomic era as less determinate, and the emergence of atoms as the "selection" of a specific spacetime structure, along with laws of physical interaction that could define that structure.

    When we look back today, and develop theories about the early history of the universe, we can see that history developing in accordance with the same laws that pertain to the universe today, the same basic spacetime structure. But the question is whether the basic explanation for those structures lies at the beginning of the universe, or has to do rather with the emergence of systems that can define themselves.

    Yes, we can think of "defining" as purely conceptual, and (again) things are whatever they are whether or not anyone bothers to define them. But QM seems to suggest that unless something exists in a physical context that can make its definition observable, it can not be determinate.

    So I'm thinking of "defining" something (in a physical sense) as putting it in a context in which it's potentially measurable. That doesn't necessarily involve humans (depending on your interpretation of QM), but maybe it does necessarily involve atoms.

    But I seriously doubt that we're going to get to an understanding of atomic structure from a top-down level either, if I understand you correctly. My guess would be that the very particular combination of structures and dynamic principles that allows atoms to exist couldn't be "predicted" by anything -- any more than the emergence of some very unusual self-replicating system of molecules could have been predicted on the pre-biotic Earth.

    I'm imagining that if we had a good analysis of all that's involved in doing what atoms do, we might well be able to see which aspects are more "primitive" and think about how this functionality might have evolved.

    Given that essentially everything about atomic structure is "well understood" in contemporary physics, this seems doable. But since the very concept of "functionality" seems foreign to physics, it's not very clear how such an analysis would proceed.

    So maybe this does remain merely a "philosophical" notion, for the time being?

    Thanks for the feedback --

    Conrad
     
  11. Mar 26, 2009 #10

    ZapperZ

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    Then I just have a very simple question. What is it about the definitions of space and time based on Special and General Relativity that is SO inadequate in your book? What empirical evidence that you have that requires the overhauling of such definitions. And how does a "philosophical" discussion about it can somehow resolve such a thing. Where has this happened before in physics?

    Zz.
     
  12. Mar 26, 2009 #11
    It seems to me philosophy is free to contemplate this topic without the confines of laws of physics. After all science of physics germinated from philosophy and grew on it's own but it does not supplant it's progenitor. So please excuse me for commenting out of the box of physical concepts.

    I like Jarle's comment but agree with Dave that the human experience came far too late to account for the existence of atoms and space. The fact that matter and space existed LONG before humankind is a key to the realist view that objects are prime and human life or preferably human 'consciousness' is an epiphenomena of objective reality.

    The problem with this seeming logical deduction is that QM has discovered phenomena that turns our logic into a swirl. How do we account for the fact that everything occurring inside the atom is in the 'wave' form superposition until WE interact with it by trying to locate, measure or weigh it? Basically there are no particles until we look at them. On a larger scale, there is no atom until we 'look at it'. There is not molecule until we 'look at it'.

    I agree, the space/time reality was not produced a few thousand years ago when first Homo sapiens contemplated the moon for the first time (Yes, Albert, it is there when we are not looking) but QM seems to prove it was not there in the particle state. Therefore there ARE NOT ATOMS or SPACE to separate objects until some sort of consciousness forces the wave/vector collapse into the particle state.

    As I understand it that is the facts of the new physics. But in this forum what matters is if it is philosophical. To my mind, few things are more philosophical then the above.

    Qmystic
     
  13. Mar 26, 2009 #12

    apeiron

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    This sounds like a mindless anti-philosophy rant. The real story is about levels of discussion. You can chose to be working at the level of models, or meta-models. And good thinkers seem to skip productively back and forth.

    Relativity would seem to have a few meta holes. Like why time has a direction, why spacetime is grainy on the quantum scale, why there are just three spatial dimensions not some other number, how nonlocal effects are possible, stuff like that.
     
    Last edited: Mar 26, 2009
  14. Mar 26, 2009 #13

    disregardthat

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    What is dinosaurs and rocks if there are no one to define the concepts of dinosaurs and rocks? We observe our world and define our concepts based on our experience. Indeed, we can postulate with varying degree of credibility what happened before our existence, but the point is that these postulations are always within our framework of terms and concepts.
     
  15. Mar 26, 2009 #14

    DaveC426913

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    Exactly what they were before! :grumpy: You assertion is just crazy.
     
  16. Mar 26, 2009 #15

    ZapperZ

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    And these holes can be plugged in by.... a philosophy discussion?

    No one here is staying that physics is complete. In fact, I don't buy into that idea that it can EVER be complete. But why would a philosophical discussion be the answer? Why not a.... horrors! A physics discussion?

    We also have holes in our understanding of high-Tc superconductors. Would the philosophy people like to tackle that too? I'd like to hear an explanation of the origin of the pseudogap in those underdoped phase of the cuprate superconductors, please.

    Zz.
     
  17. Mar 26, 2009 #16

    apeiron

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    More ranting.

    If you were saying that most academic philosophers are currently producing noodling crap then I would probably agree with that as a first pass analysis.

    When I was doing neuroscience, I found the contribution of external "philosophers of mind" to be fairly pathetic. The "real" philosopy - or rather I would prefer to say meta-theoretical discussion, as that is what it really is, the big picture that guides the scientific activity - came from neuroscientists, theoretical biologists, systems scientists, neural networkers. A broader class of thinkers, but not too broad.

    A second point is that most of physics and science involves questions of technology, of application - modeling for the purpose of control. Your high temperature superconductors would be an example of that. The models don't have to be "true", just work.

    I mean BCS and Cooper pairs? Wearing my philosophers hat, that idea does really worry me. But as a simplified model of the reality, one that leads to do-able equations, who cares so long as it does the job?

    The situation becomes different as we get out to the extremes of physics - the realms of the very small and very large. There we are more concerned about the truth and the complexity. Observation starts to fail, control becomes less the issue. What we need is "quite probably true" models of reality that can then be projected into realms beyond reach of our telescopes and microscopes. Realms where there will only ever be theory. Realms in which we will only ever be doing "philosophy" in fact.

    So to turn your whole story around, scientist need to be good technologists in the easy areas and become good philosophers at the extremes.

    You could shut down all the philosophy departments and it would make no difference to science perhaps. But science needs to be able to behave differently when modelling easy stuff and modelling hard stuff.

    You are suggesting a rigid inflexibility which sadly is too often the view of the technology-focused.

    As a cynical aside, and a reason for my irritation, I see the distortion taking place in high-end physics these days. The hordes of string theorists. The billion buck supercolliders.

    Much of this is a manufacturing of theories tailored to the purpose of winning grants. The theory can be lame, but if it makes a "testable prediction", then great. If it is going to cost a lot of money and create a lot of posts to test, then even better.

    Big physics is a becoming a job-creation scheme. And it is all justified by empiricist hard-nosed rhetoric. It would be scary if "philosophy" could do it cheaper with a few smarter guys.

    The same phenomenon happened in neuroscience with neuro-imaging. I was there. I knew the lab bosses who went to Cern and came back wide-eyed at the empires they would be able to build. And where are the results?
     
    Last edited: Mar 26, 2009
  18. Mar 26, 2009 #17

    ZapperZ

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    At what point is science inflexible? After all, it wasn't philosophy that change our view of our world, it was SR and QM.

    My ability to comprehend an "electron" separating out into its charge and spin independent of each other requires A LOT of flexibility and ability to accept something that even philosophers cannot comprehend. How is this "inflexible"?

    Asking science to be flexible (which it is) has nothing to do with discussing such a thing philosophically. Since when does one automatically implies the other? I'm not questioning that science should be "flexible". I'm questioning the usefulness and the rational of discussing the topic at the realm of philosophy.

    Zz.
     
  19. Mar 26, 2009 #18

    Pythagorean

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    It's like when the government throws out "fishing" funds. It's hit and miss, but if there's enough knowledge involved in the discussion, innovation can happen, whether it's academic innovation (seeing something in a new way that helps you to understand other things or more readily remember the mathematical and logical techniques involved) or research inspiration (the possibility that you, as an experimentalist, could be inspired to try a new experiment out to answer a question that comes up in the discussion).

    For the most part though, we can't deny it's just for entertainment; a casual discussion of interest.
     
  20. Mar 26, 2009 #19

    apeiron

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    To me this is demonstrating the inflexibility of thought I am talking about. Me clever scientist, you dopey philosopher. Ugh. End of story.

    You are basing your whole point of view on the assumption that scientists and philosophers have ways of modelling that are fundamentally different. Yet I'm not hearing any interesting evidence as to the claimed nature of the difference.

    I am putting forward the alternative view that modelling is modelling, and there are different levels of abstraction - it is a hierarchy of modelling. Down the bottom, you have science as technology, up the top, you have science as philosophy. And neither is better. Both have their uses.

    This is a field with a literature. There are information theoretic arguments to back up what I say. It is possible to have a scholarly discussion of the issues.
     
  21. Mar 27, 2009 #20

    ZapperZ

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    ... and what kind of discussion would that be?

    Just look at what YOU have said here already. You indicated your uneasiness about "cooper pairs", etc. This is EXACTLY why I asked why a philosophical discussion would be any better! The evidence is right there. It appears as if personal preference is a valid argument against a physical concept, and that is exactly what is being discussed here. That is as meaningful as a discussion on favorite colors. And one wonders why discussion in this forum often goes nowhere....

    I can easily point to the "uses" of science discussion. I've asked for the worthiness of such a discussion in the philosophy forum here. NO ONE appears to have been able to provide me with a valid reason. Instead, there is this red herring being thrown out that (i) science is incomplete and (ii) science needs to be more flexible! None of these touted the possible uses and evidence that a philosophical discussion can actually ADD to a VALID understanding of what is being discussed. I've explicitly asked for what possible shortcoming of SR and GR's definitions of space and time that a philosophical discussion can provide. Instead, all I get is that space and time have problems as the small scale, as if philosophy CAN answer such problems. What kind of a scam is that?

    This is no different than justifying Intelligent Design simply because there are gaps in our understanding of Evolution.

    One last time: How does a philosophical discussion on the possible definition of space and time able to add to the body of knowledge that is beyond what has already been defined in classical mechanics, SR, and GR? If there is no reasonable answer for this, it ISN'T ME that is bashing philosophy. It just is. Saying Politics cannot provide insight into the Dark Energy problem isn't a bash against politics. It just was never MEANT to do that!

    Zz.
     
    Last edited: Mar 27, 2009
  22. Mar 27, 2009 #21

    ZapperZ

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    Can you provide valid evidence where this has occurred before from such philosophical discussion by professional philosophers?

    Zz.
     
  23. Mar 27, 2009 #22

    ConradDJ

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    As for me, I don't think much has been accomplished in academic Philosophy since the 1920's, around the time QM got going. Since then, the real conceptual challenges have been opened up by Physics, and the philosophers have helped very little, if at all. This is just my prejudiced opinion.

    On the other hand, it's been very difficult for physicists to step back from the technical issues -- which have been huge and have prompted brilliant work over several generations -- to find new points of view on the fundamental issues. I'm much more interested in what physics has discovered about nature, than about philosophical arguments. But what interests me about physics is that it challenges traditional assumptions at such a radical level.

    For example, in the above discussion, we're going back and forth between the idea that everything exists objectively in itself, and the notion that things are defined by human consciousness. Neither or these viewpoints, I think, is adequate to deal with the world described by Relativity and QM. Physicists tend to treat spacetime and quantum superpositions as "real things" existing in themselves -- even though the nature of this "reality" is very different from the world we experience. That viewpoint works to a great extent, as a basis for productive work in physics, but I think it avoids deep issues, and may not lead to deep explanations.

    On the other hand, I don't believe human consciousness has anything to do with the way the world is defined at the physical level. It's a symptom of our philosophical inadequacy that we keep jumping way up to the human level as soon as "the observer" shows up in physics. What appeals to me is trying to understand what "observing" and "defining" mean at the physical level. Carlo Rovelli's Relational QM is an excellent example of work being done at this level, by physicists. It's about time some philosophers caught up.

    What I was proposing here is that atomic structure has a unique role to play here, and that understanding the role of "the observer" in Relativity and QM may require an appreciation of how unique that structure is. I'm trying to look at something in physics, and learn from it how to think about the world in a new way.

    Back in the 19th century, atoms were (for many) the equivalent of a Unified Field Theory in the 20th -- the basic, simple entities that explained everything and needed no further explanation, because they were so simple. Now we know they're complicated, and get more complicated the deeper you go into the subatomic realm. Physics has continued the quest for something basic and simple at deeper and deeper levels... and has learned a great deal, but there's still no simplicity in sight. It might be a major philosophical shift to come up with a different way of explaining what's going on here.

    Conrad
     
  24. Mar 27, 2009 #23

    Pythagorean

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    nope. I can provide anecdotal advice for my own academic understanding. It's not the philosophers themselves though; it's the scientists correcting the philosophers where I learn.

    It's part of the whole point of internet forums in general, to exchange ideas. Just because you're trained in physics doesn't mean you think of every possible question you can ask.

    Philosophical discussions is where I find the interesting questions, not so much the answers.
     
    Last edited: Mar 27, 2009
  25. Mar 29, 2009 #24

    This is a common-sense view that makes sense to a human being, but i don't think it paints a realistic picture(I could be wrong but i don't think common sense is valid tool to explore the initial state of the universe). Anyway, this must have been the time when a phase transition took place and relativity took over. Nowadays space, matter, mass, velocity, energy and time are all relative to the observer's frame of reference. Thus, the idea that there are objects having objectively existing, absolute properties such as size, mass, energy and age is an illusion. Because their values are different for different observers, these properties have no meaningful existence independent of the reference frame of an observer. More and more of the world that we once thought was objective is now seen as determined by the point of view of the observer. So despite the vagueness of the statement, the question "Are space and time definable without atoms?" is reduced to the statement - Space, time and atoms are all relative terms coined by us to depict and dress in physical laws our subjective experience.

    This is going to cause an outcry from the realist camp, but both relativity and QM bear some striking similarities for their requirement to renounce the existence of fundamental physical notions. In particular, while relativity has forced the renunciation of the absolute significance of space and time, replacing them with spatial and temporal measurements that have meaningful existence only in relation to a selected reference frame, quantum theory has forced the renunciation of the absolute significance of objectively existing properties, replacing them with observable quantities whose possibility of measurement depends on the selection of a measurement apparatus - i.e there are no particles until there is a measurement. The selection of a frame of reference in relativity is similar to the selection of a measurement apparatus in quantum theory insofar as without them, no objective meaning can be given to the quantities which we normally attribute to objects while measuring/observing them.
     
    Last edited: Mar 29, 2009
  26. Mar 29, 2009 #25

    DaveC426913

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    Common sense? No, this is part of the Big Bang model.
     
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