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Nonphysical universe?

  1. Jan 3, 2009 #1
    Can anything in the universe be described as nonphysical? I often here mystics describe a particle's wavefunction as nonphysical. Some look to the uncertainty principle in their attempts to support claims of a nonphysical substrate.

    As I understand it, a wavefunction is essentially a probabilty function. Until it collapses, we can only predict the probabilities (so called, quantum determinism using Schrodinger equations) of any pair of variables used to describe a fundamental particle, e.g. location and momentum.

    I quess there are two issues here that may or may not be related; one is, whether the universe contains any nonphysical stuff, and the other is whether I'm basically correct about the wavefunction and uncertainty.
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  3. Jan 4, 2009 #2
    A wavefunction is non-physical in the sense that you'll never encounter a wavefunction as such (a complex valued function) in experiments. The only thing you measure upon are amplitudes (which are real).

    You have to be careful with what you call non-physical and what not. Physics as such tries to describe nature, it does not claim it is nature. So a theory may use non physical entities (eg a complex valued function), it must give physical results (eg real amplitudes), which one can test in experiments.

    In the case of quantum mechanics one starts from different postulates and then works trough them in a consistent way. One of the conclusions one draws is that for observables (which are represented as hermitian operators, this is a postulate) which do not commute (eg position and momentum) one cannot know both values at the same time. Only the probabilities for the values are determined fully at any time. This conclusion is indeed a direct consequence from the postulates (with the help of some mathematical equivalences).

    One then can indeed ask itself if the universe is non-physical because the non-physical description seems succesful (the conclusions are physical), but I think this question is irrelevant because one can never know. (logically A->B and B does not give A) Every description with the same results which seem to be physically correct is good. Only not-B give also not-A and so in the case of wrong results one can definitily say the description is incorrect. This is exactly how physics and thereby any science paves its way.

  4. Jan 4, 2009 #3

    Thanks for your reply; however, I'm not sure I agree that the question of whether the universe is fundamentally physical or nonphysical is irrelevant, and that it is essentially unanswerable. Even though a certain answer is very likely beyond human capability, coherence with hard evidence about what we do know strongly suggest, I think, that material things "beget" other material things. Moreover, there are no instances that I know of where something non-material has ever given rise to something material.

    And yes, a wavefunction itself is not a physical thing; but, is it not a mathematical construct used to describe fundamental particles that are indeed physical things? In this sense then, is it not reasonable to say that physicists in their attempt to describe nature often employ nonphysical abstractions to help them better understand what they take to be the physical universe we live in? As you say, physics nor its abstractions are nature, they merely represent our best efforts to describe it.

    I hope you can add to your earlier comments as I'm still having some difficulty rejecting what coherence with hard evidence suggests; that is, the inescapable conclusion, at least as I see it now, that the universe is fundamenatally physical. What am I missing?

  5. Jan 4, 2009 #4
    I think that in the first place one has to define what is meant with something physical. In my opinion I would define it as how we observe the universe in a real sense, that is by experiment. So in this definition one eliminates the question whether the universe is physical or not: it is physical, at least if we believe the universe is exactly as we observe it. Because if we believe that and if we believe it is in principle possible to observe the universe as a whole, then the universe is by definition physical. Of course one can object and believe it is impossible for humans to grasp the universe as a whole, which would make it unphysical. But this would be a consequence of our limitations as parts of the universe (and our definition of physicality), not an absolute feature of the universe. An even simpler definition is defining the universe as physical. So one answers the question of physicality by defining the word physical. This makes it irrelevant I think.

    Now take the first definition. Then it is possible to get physical things out of unphysical things (energy values out of infinite dimensional complex vectors). So the coherence of this unphysical description with hard results only says that the unphysical description is a good one as far as our knowledge of the world is concerned (the measurable results the discription gives). It has no sense to conclude that the world is the unphysical description. And if it was then one must be possible to check it, which would make it physical.

    One can in this image interpret the unphysical universe as something arbitrary: as long as it is consistent with the physical knowledge, it's ok. The process of physics then is to make a complete consistent theory, thereby making the (unphysical) universe physical. I think this is impossible, because there will always be needed unphysical things to make physical conclusions. And as long as there is something unphysical in the theory, the theory is just a theory and not the blueprint of the universe.

  6. Jan 4, 2009 #5
  7. Jan 5, 2009 #6
    I don't put much stock in what 'mystics' say, but did you mean metaphysical?

    And if not, whats the difference you see between metaphysical and nonphysical?

    It sounds like you are trying to reconcile the empirical and the rational, something the philosophy of science has been struggling with for centuries. Geometry being an example of the rational or logical, in this sense, and everyday experience being the empirical.

    Defining consciousness also runs afoul of this issue, so that may be where the 'mystics' are coming from. They tend to enjoy abusing the uncertainty principle and the observer effect.
  8. Jan 5, 2009 #7
    Joe and Hendrik,

    I would say metaphysicians try to answer questions about the assumptions scientists take for granted. In a sense, they are involved in a search for knowledge about the thing in itself--an objects essence. Scientists tend to dismiss these questions as irrelevant because they believe metaphysical questions are not answerable and they are very likely right about that.

    A good metaphysician is open to the possiblity of the universe being fundamentally nonphysical. But, as I see it, to discount the implications of coherence with known hard evidence about what we think we know would require stronger evidence, or at least one counter example in support of physical things (forces or matter) arising from nonphysical things (ideas, mathematics, spirits, gods, etc.). The mystic presumes, without offering credible evidence, the latter by positing some version of panpsychism.

    Since Kant, intellectuals have been divided into two camps--realist who believe the world can be known mind-independently; that is, we can know directly the thing in itself--and the antirealist who would deny this. Antirealists argue that we can't know the world mind-independently; that is, we depend on conceptual frameworks to make sense of our experience of a world external to mind--the real world.

    If I understand Hendrik correctly, he is cautioning against thinking the conceptual framework is the real world so he would be an antirealists. I'm an antirealist as well but unlike Hendrik, I think we can reasonably speculate about the "unknowable" as long as our speculations are logically consistent with the hard evidence we have about the world we think we know. I believe this rules out a world that is fundamentally nonphysical.

    Taking the position of a skeptic--we can't know, so the question is irrelevant--is easy. It also seems not to appreciate the importance of the role of coherence when speculating about what we don't yet know or may never come to know.

    I invite the nonskeptics here to answer my original question which I am here modifying to remove what has become a side issue about descriptions of things and the thing itself. Is the universe fundamentally nonphysical or physical?

    In pondering your answer, keep in mind that you need not rely on knowledge that is absolute or certain, only on knowledge defined as justified true belief. Here, belief is your starting position--call it what you will, your hypotheses, assumptions, etc.; justification depends on the strength of the evidence currently available; truth is a function of the probabilities assigned to your confidence in alternative and perhaps even competing evidential explanations for the phenomenon being examined. If the evidence changes so does what we call truth--no capital T truth in this concept of knowledge. As such, I don't think a reliance on hard skepticism is a reasonable position.

    I acknowledge that we can't now know and may never know in any absolute or certain sense the answer to my question. Nonetheless, let's here what your justified true belief is about the fundamental nature of the universe.

    Last edited: Jan 5, 2009
  9. Jan 5, 2009 #8


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    Huge read!

    What I'd like to propose is that "conscious-awareness" is a simple loop-back system generated by neurons communicating with one another, basically confirming that they are firing and firing in response to the same or related stimuli... plus or minus the autonomic responses associated with peripheral, environmental and other stimuli.

    There may be a further, less studied component to conscious-awareness in the role DNA/organelles and other cellular "parts" play in its generation.

    But I think there is need for a distinction between "cellular reaction" to stimulus, self-generation of stimulus and awareness of stimulus.

    It is fairly obvious that "conscious-awareness" ends when an organism expires. This should provide the evidence that it is purely physical in nature. Whether we imagine we are aware of "the light" upon death or that we can see the top of the examination scope in the operating room, people are still in a state of "living" when these things happen... even if their vital signs appear to be flat. So these anomalies are self-generated, gathered from a store house of experiences that have been etched into neuronal patterns, possibly by way of Transsynaptic Control of Gene Expression.

    This is one of many functions that allow Cognition to take place in the brain... and possibly other parts of the body. I think cognition might be something to look further into with regard to conscious-awareness and the purely physical aspects of the condition.

    With regard to the OP's inquiry, how can a universe that is entirely dependent on (physical) energy be non-physical at any scale?

    below from http://arjournals.annualreviews.org...6.030193.000313?cookieSet=1&journalCode=neuro

    Attached Files:

    Last edited: Jan 6, 2009
  10. Jan 5, 2009 #9


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    Hi Dave,
    I don't think you'll get anywhere asking if the universe is "fundamentally" non-physical or physical. I'm not even sure what that means. However, if your focus is on consciousness, and whether or not that is a physical or non-physical sort of thing, you might be interested in Chalmers' paper, http://consc.net/papers/nature.html" [Broken]. Here, he defines various materialist views on consciousness and attempts to make the case that consciousness is a non-physical phenomenon. That isn't to say that consciousness isn't in some way supervenient on the physical (sorry for the double negative there). As far as we can know, consciousness depends on the interactions inside one's brain for the phenomenon to come about. But at least, Chalmers argues that there are aspects of consciousness that can never be deduced from physical interactions, and I'd have to agree with that. From his paper:
    Last edited by a moderator: May 3, 2017
  11. Jan 5, 2009 #10
    Nonphysical, as in, not made of matter and/or energy?
  12. Jan 5, 2009 #11
    I explain away most 'non-physical' things like consciousness as being verbs, not nouns - that is, consciousness is is a property of a system in motion. When the brain stops moving the way it does, 'consciousness' goes away. The system itself is quite physical, the property is an emergent behavior.
  13. Jan 5, 2009 #12
    Maybe someday someone will figure out a way to collect/harvest and transfer thoughts/emotions/consciousness...like computer files...to another host. Ultimately, it might be the only thing in this discussion that can be proved...until then...

    Last edited by a moderator: Apr 24, 2017
  14. Jan 5, 2009 #13
    Actually, one could say that mathematicians, as in pure math, are dealing with metaphysics, where 'physics', or science relies on a study of empirical, what I think you mean by physical, evidence. Mathematics becomes less metaphysical when it is applied....

    Add to that that even modern science which is an outgrowth of empiricism does not limit itself to that. Theoretical physics for instance has a solid basis in the physical, but relies on rational, logical arguments to extrapolate beyond what can be observed. Physical observable facts however don't require one to extrapolate. So all prediction is based in some form of metaphysics.

    I think the problem you have here is that you are implicitly treating 'empirical' evidence as 'stronger', without saying why. Plato's idealism for instance posits that geometry is the most 'real' thing and that what you would call physical is merely an imperfect manifestation.

    How can one have strong 'physical' evidence of non-physical things? Let alone, strong 'physical' evidence that physical things arise from non-physical things.

    And are ethics non-physical? Because our ethics give rise to physical action seemingly as much as physical actions give rise to ethics.

    Kant was influencial, but I think you're giving him way too much credit, and oversimplifying what is quite complex.

    Plato's cave analogy addresses what in more modern terms is called phenomenology and even before that, Protagoras said: Man is the measure of all things...

    Phenomenology is key to an understanding of issues relating to a modern discussion of physical/non-physical.

    I think one could make a convincing argument for either case, depending on what assumptions(definitions) one started with and what evidence one decided to value. In other words, depending on one's metaphysics.
  15. Jan 6, 2009 #14
    First off, the 'physical' limitation on evidence is yours not mine; I merely said stronger evidence. But you underscore my point. If someone claims that at the most fundamental level the universe in not physical, they are in essence saying that, in a yet to be explained way, some nonphysical whatever gives rise to the physical world we experience. If this did in fact happen, there should be some evidence to support it. What kind of evidence that might be and how we can come to know it, is an open question.

    I thought Hendrik warned us about this. We should not mistake our abstract explanations of the universe for the universe itself.

    I agree but what we are discussing goes beyond validity to soundness and whether coherence should circumscribe our speculations.
  16. Jan 6, 2009 #15


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    I like what Neils Bohr said about this...

    "It is wrong to think that the task of physics is to find out how nature is. Physics concerns what we can say about nature..."

    Further to that... we rely on physical systems (perception, congnition, awareness) to "find out" what we "can say about nature". How does one propose to find evidence of a "non-physical" state while using a purely physical means of perception?

    Further to Joe Dawg's argument that perception or consciousness can be analogized or metaphorically described as the "emergent phenomenon" of a physical process... it is a physical process based in physical parametres. It will not exist as a separate entity and must be observed by and within the same physical parametres that it is generated.

    Using another metaphor to demonstrate this... one could erroneously designate music as the "emergent phenomenon" of human vocalization, instruments and technology. However, a closer examination would show that music relies solely upon physical conditions (atmosphere, air pressure, etc..) to exist and to be perceived.

    Similarly, conscious-awareness requires the physical structures that make up the brain or the cerebral ganglia in many organisms. At no point does conscious-awareness become a separate element and amorphic or non-physical in nature. It can always be observed as the consumption of glucose, the electrical activity, the workings of the neuron's sodium-potassium "pump" and the corresponding functions of the neurology of the observer.
  17. Jan 6, 2009 #16
    But is that a false dichotomy? Physicality is not very well understood, and one could have a different understanding of it than you do. One that doesn't involve a binary. In fact, it seems more likely to me, that what you call physical and non-physical are simply aspects of the same underlying thing, in which case, neither one arose from the other. If one assumes such a binary though, I see no more reason to assume that the non-physical arose from the physical than the reverse. After all, even in physics the idea of a big bang and the beginning of time/space, which means something arose from nothing. Physical from non-physical?
    Physicality is an abstract explanation.
    What constitutes sound?
    Something can only be coherent in relation to something else.
    Is the relation abstract or is it only our description of the relation that is abstract?

    The best one can do is detail a set of assumptions and work from there.
    This is why Plato turned to geometry and Descartes turned to the mind.
    What is the foundation of your notion of physicality?
  18. Jan 7, 2009 #17
    No doubt! But here we have been talking about the physical (energy and matter) as opposed to the nonphysical (the mental, spirits and the supernatural).

    And what may that thing be? After you name it, tell us what caused it or if it is self-caused.

    That's odd! In my almost 70 years of living a well travelled and unsheltered life, I have never experienced something nonphysical give rise to something physical; but I have experienced almost everyday something physical and even something nonphysical, if you want to count abstractions, emerge from the physical.

    There are many so called "before the BB theories"; the one I like--QMF--does refer to a scientific notion of "nothingness". But this is a bit of a misnomer in that the so called void or vacuum is not empty. It is filled with energy acting on quantum mechanical fluctuations of fundamental particles (physical stuff) that burst in and out of existence. However, the net result of particles coming into "existence" and being annihilated is not zero. In other words, in this theory anyway, the origin of the universe came from something not nothing and that something is physical. To claim otherwise--something arose from nothing--is to claim a known value in violation of the uncertainty principle.

    Moreover, I think you make a common error by saying something that is nonphysical is nothing or without being. Nothing is not something, it means no thing, nonbeing. I presume when folks talk about the nonphysical, they believe they're talking about something not nothing. If nonphysical things are no things at all or nonbeings, then we have the answer to my original question.

    Not as I have been consistently defining it.

    Validity only goes to inference consistency whereas soundness goes to the truth of one's initial premises (starting point or belief) and subsequent inferences derived therefrom. This relates to JTB discussed earlier in this thread. There I define belief, truth and justification.

    I agree. That is why early on I defined coherence as evidence that is consistent with the hard evidence for what we think we know and that this principle of coherence guide our speculations about what we want to know. I am not asking for an absolute or certain answer to my question, only one that is informed by coherence.
    Last edited: Jan 7, 2009
  19. Jan 7, 2009 #18
    Ahh.... thats a problem, you have a pretty good understanding of the physical, but your non-physical definition is simply a catch all.

    The supernatural is Nonphysical is at best a tautology
    The mental is Nonphysical, could simply be wrong.
    Spirits in whatever sense you are defining them may or may not exist. If they exist, in what way are they not physical? Simply not made of matter/energy? What are they made of then? If you don't know, how can you compare?

    Now you're just being silly. Do you intend on telling me what caused matter and energy when I do?
    You've never had an idea, which you then implemented? You've never designed (mental) and built something? By your definition mental is non-physical.

    So you're saying that everything, including the non-physical, has to follow physical laws? Hmmm. Which would make the non-physical, by your definition, physical.
    I'm not saying it, you are.
    Its your binary definition. Something is either physical or not, no?
    I'm thinking the problem is your use of the negation non-physical. If its not matter or energy it could be no-thing. Unless you mean no-thing is actually physical, in which case, its something and therefore physical.

    Do you not see how this is a false dichotomy?
    My main problem is with your insistence that you understand the non-physical. Clearly the non-physical would not be held to the same set of rules as the physical. So using logic based on the physical might simply not apply. In fact, as a physical being, assuming the non-physical exists, you would really have no way to reference or understand it, since it is separate from you in every way. You could not even interact with it, it would need a physical aspect for you to do that.

    So your argument comes down to: The universe is physical, because its physical.
  20. Jan 7, 2009 #19
    Or, everything non-physical is everything that isn't physical...we just don't know what it is or how to define it?
  21. Jan 7, 2009 #20


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    Nothing (nonphysical), by definition, does not exist. Pure and simple.
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