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What is the universe ?

  1. Oct 21, 2010 #1
    everything about science, including relativity, is all about how we measure things. how our surroundings affect us.

    in other words, our knowledge is based upon how we perceive things. this can be different from how things actually are, and in my opinion, i think it probably is different from how things actually are.

    while our perception of the universe is of interest to me, not nearly so much as what the universe actually is. the frustrating part of this for me, is that i do not think it is knowable for us. we are stuck in the black box of our perception.

    for example, if you take a surface area of a sphere (at any radius), and imagine 2-dimensional beings living on it, they have no way of knowing that they are part of a sphere, with an actual center to it.

    whereas we could view the sphere in its entirety, and know exactly what it is.

    i have often wondered if that same analogy is at work in our universe. in other words, is our universe part of a greater dimensional thing ?
  2. jcsd
  3. Oct 21, 2010 #2
    The statement is incoherent. Asserting that there is some sort of reality we are unaware of is, in its own rite, a statement about reality and an assertion that we can know something about it.
  4. Oct 21, 2010 #3
    Have you read Flatland by Edwin Abbott?
  5. Oct 21, 2010 #4
    It can be hard to face the fact that no matter much your analysis of your perceptions seem to transcend the immediacy of that perception, it is still part of your subjectivity and thus your perception. By definition, no one can ever "know" anything beyond human knowledge. The moment a human knows something, it exists within the realm of human knowledge. Therefore, if anything exists in any form that is totally unknowable, it will never be known to humans. If it is in any way knowable, it will probably eventually be known. Interestingly, there doesn't seem to be any limit to how far knowledge can progress, perhaps because of the role subjectivity plays in synthesizing perception with the ability to analyze and process the data and resulting knowledge ever further.

    So the question I think you should be asking is "what is it about your subjectivity that causes or allows you to imagine that there is more to reality beyond your perception and/or knowledge-capacity?"
  6. Oct 21, 2010 #5
    hi insanity,

    i have heard of the term flatlanders, but i have not read the specific book that you mentioned. i know carl sagan uses that term in his tv series, "cosmos".

    hi brainstorm,

    i stated an example whereby the "flatlanders" will never know the sphere. it is outside of their ability to know. i simply think that we are also in this same situation.

    for example, when we look out among the stars, we do not see how things are, but how they used to be. this is because the speed of information is not instantaneous. i think this gives us a skewed perception of our universe.

    i think there may be things within this universe that are not knowable to us. because of our size, we may have limits in either direction. quarks supposedly make up protons and neutrons. does something make up a quark ? does something make up the something that makes up a quark, etc. there simply may be limits as to how small we can ever have perceptions about. or how big.

    but outside of the universe, by definition, is not knowable to us.

    "outside of the universe" is still reality, but we are not connected to it.

    you asked why my subjectivity ponders that possibility, or thinks it is likely - partly because i am humbled by it all. partly because of our limitations on perceiving the universe. partly perhaps of gut feelings after living 55 years.

    i suspect that spacetime is not what einstein thinks it is. just like newton had equations that fit very well, his idea on what gravity is, is way different than einstein's version of what gravity is.

    i very definitely relate to einsteins comment about "i want to know the mind of god. dont bother me with the details." i think this statement has something to do with wanting to know the purpose of us and the universe. but i also think it has something to do with how things really work at the highest level, and not how they seem to work by our perceptions.

    i think time and light represent barriers for us that we wont be able to overcome. i dont think humanity has the foggiest idea of what time really is. we simply perceive it as a way of separating two events. if there was no motion, would there still be such a thing as time ?

    i was a math, science, and computer major in college, and continue to keep up an interest in various aspects of science. but it is my guess that science has its limitations.

    i am agnostic about god, because by our very definition of god, he "exists" outside of this universe, because he is given credit for creating it. therefore, there is no rational opinion about god, cause there is no information with which to have an opinion.

    but i am hopeful that god exists, and that i may become aware of the mysteries of life that most of us think about every now and then.
  7. Oct 22, 2010 #6
    That is why it's time to repaint the box in some other color. What color? Well, use your imagination.

    And speaking about imagination this is one of my fantasy stories that "answer" the question "what is the universe?":

    [fantasy story]
    The universe is one big simulation project. Unfortunately the developers were not careful and left back doors to the main computer resources. As we are already tapping into the main computer resources with our quantum computing the supervisor will notice there is something wrong. On 21 Dec 2012 he will run his equivalent of anti-virus program to wipe out the anomalies....
    [/fantasy story]
  8. Oct 22, 2010 #7
    The sphere might not be the best example to illustrate your point. It turns out you can potentially identify a whether a universe is spherical without reference to "outside of the universe". If you're able to make measurements over big enough portions of the surface, given the sensetivity of your instruments, you'll find that Pythagoras's theorem doesn't work as it would on a plane, that the angles of a triangle add up to more than 180 degrees, that the circumference of a circle is less than 2πr. Walk far enough, and you'll get back to where you started.
  9. Oct 22, 2010 #8
    Do you realize that each unknowable instance you describe only seems unknowable because of a conflict in conceptual frameworks?

    Here you are assuming that it would somehow be natural for light-information to exist simultaneously at different points. This may seem natural to you based on your perception of immediate surroundings relative to each other and time as you perceive it, but why would you assume that simultaneity between observer and observed is a natural state from which the heavens are a deviation?

    How do you know these particles exist except as props in a scientific theory/model that make equations function well to predict outcomes?

    The concept of universe, by definition has no outside. It is the set that contains all possible elements. You are assuming that if the universe is infinitely large, there must always be a subsequent container beyond each subsequent container of everything else. That is a conceptual artifact that simply produces a logical anomaly, imo.

    No, I didn't mean the emotional stimuli to ponder. I meant the conceptual logics of your cognition and how these could reach the point of imagining that there is more to know than there is to know. Why wouldn't you simply assume that you can only know what you can know and no matter how far you explore or think, you will only ever be expanding possible knowledge and never transcending it? What gave you the idea that it is possible to transcend the possible?

    What could a better theory of gravity explain that Newton and Einstein don't, iyo?

    I have read that Einstein didn't like quantum theories because they substituted pure math for intuitive models that explain instead of just predicting. I can also relate. While I see the value in predicting outcomes, I long to understand the hows and whys of what is going on with phenomena.

    I don't think time exists except as delineated motion of a mechanical device deemed a clock. I don't think clocks measure anything outside themselves called "time." I think physical forces and energy produce motion and there are regularities that cause motion to occur in a predictable manner relative to other motion. Physics is basically the study of commonalities/patterns in physical behaviors, so time is basically a self-referential artifact of physics. Two clocks run at the same speed for the same reason two balls fall at the same rate of acceleration, for the same reason two identical basket balls with the same pressure will bounce to the same height when dropped on the same surface. Any machine with contant/regular motion can be delineated with markings that are synchronized to markings on another such machine (clock). Given that the markings made on the one machine are done with reference to the other and nothing changes to alter the speed of the machines, they should stay synchronized. Now don't ask me about time-dilation, though.

    You don't assume that science can indefinitely transcend its own limitations? I assume it can, but ironically without ever going beyond itself.

    By one definition, God may exist outside the universe (although that is a logical contradiction by virtue of the definition of the concept, "universe" as I already mentioned). By another definition, God exists as part of human subjectivity, and specifically as an artifact of faith.

    If God exists, then you would assume that all the information needed to fully know him/her/it is available via scripture and inherent human abilities to explore one's own subjectivity/soul. I would recommend taking the somewhat scientific route of Karl Jung and exploring the idea (archetype?) of God-within-yourself. Jung discovered that by understanding the idea of God within himself, he effectively realized God's existence. This is logical, imo, because a person in total control of their subjectivity has the ability to realize true belief as well as disbelief. This may be a fancy way of talking about faith, but I remain impressed by the ability to control one's own consciousness to the point of having the choice to pro-actively believe and "know" something that is rationally doubtable.

    Rationality causes a knee-jerk reflex to disbelieve certain things and believe others, which limits the total possibilities of human subjectivity to that which rationality permits. I think exploring irrationality has to be done with healthy regard for the caveat that irrationality can have dire consequences, but so many people are self-destructively exploring irrationality without even doing so out of conscious will, that I don't think a responsible safari into the realm of God-faith is quite so risky in comparison.
  10. Oct 22, 2010 #9
    hi brainstorm,

    you present too much for me to respond at one time, so i will respond to these two points, first.

    i did not mean to imply that lack of simultaneity is a deviation. the universe is what it is. i simply say that the tools that we have skew our ability to understand the universe as it is. i realize of course, that the purpose of the universe is not necessarily constructed so that we could have a perfect understanding of it.

    i dont PERSONALLY KNOW that said particles exist (quarks and beyond). i cant even say that i know that protons, neutrons and electrons exist. these are things that i was taught. i believe them to exist because of the science behind them.

    although our model of the electron has changed quite a bit - from the planetary model to something much stranger.
  11. Oct 22, 2010 #10
    Well, you seem to be aware of the artificiality of scientific modeling relative to the existence of things in an empirical sense. What's more, you seem somewhat comfortable with the inherent disconnect, which causes undue tension for many. Personally, I have the ability to regard modeling in a tentative way without either accepting or rejecting them as true representations of underlying realities. I do find it interesting to look for spots where the existing models can be questioned, refined, or revised as well as points where the models reveal cognitive artifacts of human perception. Your post has made me think about conceptualizing space in terms of relative simultaneity of light-emissions. It's as if the universe at the largest observable scale exists of echos and as you zoom in on a locality, the echoes begin merging into a single sound, which is simultaneity. I don't know if you intended to paint such a picture, but that is what I got out of it.
  12. Oct 22, 2010 #11
    hi brainstorm,

    no, i am not assuming that there are always subsequent containers. it is a little hard for me to grasp that anything is INFINITELY large. but the size of our universe has nothing to do with my thought process.

    since everyone uses the term "universe" already, it makes more sense to me to talk about a super-universe, as opposed to trying to rename our universe as a sub-universe.

    by my definition of our universe, it is everything that is connected to us. something outside of that connection would be part of the super-universe. however, i dont think that there is an endless number of super-universes.

    since there is no information about what is outside "our universe", i have no opinion based upon facts.

    it would not surprise me though, that the process (god or otherwise) that gave rise to our universe also gave rise to other universes.

    remember that no matter how large our universe may be, we are talking about our dimensionality. there are an infinite amount of 2-dimensional surface areas that can fit in a 3-dimensional sphere. likewise, there could be an infinite number of spheres that fit in a 4-dimensional object - of which i have no ability to comprehend what a 4-dimensional object looks like.
  13. Oct 22, 2010 #12

    Protons, neutrons and electrons do exist but it's hard to find anything more substantial than relationships to their existence.
  14. Oct 22, 2010 #13


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    The tesseract has always been one of my favorites, great sci-fi short story about it.

  15. Oct 22, 2010 #14
    Can you find anything more substantial than relationships to their existence for any other objects?
  16. Oct 22, 2010 #15
    If the same process gave rise to multiple universes, they would all be subsets of the universal set that contains all products of that process. "Universe" refers to boolean set theory, I believe, and I just googled the etymology and it means "all together" or "turned into one." So having multiple universes is an oxymoron because they would not be "all together" or "turned into one." Hence the term "subset" would make more sense.

    2-dimensional planes do not "fit" in a 3D region because they do not have volume in the sense that 3d objects do. Volume is a measure that refers to 3D. The 2D equivalent is surface area. A 4D object is a 3D object in motion and/or flux.
  17. Oct 23, 2010 #16

    What's your point? In my frame of reference everything that's observable(from electrons to cars and dogs) has definite properties and values.

    What the deep nature of the 'things' we measure and observe is, is hardly a question for science to answer. Certainly not at this point.
  18. Oct 24, 2010 #17


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    Yup. Robert Heinlien's "And He Built a Crooked House." Awesome sci-fi.

    Actually I agree with Physics Learner. It has always been a pet theory of mine that human brains evolved to survive and reproduce in the African grasslands, living as nomadic hunter gatherers.

    Its a great privilege that we do understand so much as it is. I dont think our brains can understand all the fundamental concepts re: the origins of the universe.
  19. Oct 24, 2010 #18
    hi brainstorm,

    i am assuming that the last word should have been "impossible" ?

    your post is my whole point. i know it is not possible to transcend the impossible.

    or as the borg put it, resistance is futile - LOL.

    but unfortunately, that is the information that most interests me. as einstein put it, the mind of god.

    there is no way to prove anything outside of our universe, or sub-universe, if you prefer.

    but i do suspect that it is there. and i do have rational thought processes for that.

    this universe had a beginning. this is easily seen from the way that time has manifested itself in our universe. if it had no beginning, then everything in it must also be eternal.

    this universe is a causal one. so the universe did not create itself.

    therefore, i conclude that "something" was responsible for its creation.

    trying to go any further than that is total speculation, with no information to back it up.
  20. Oct 24, 2010 #19


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  21. Oct 24, 2010 #20
    I'm not getting this concept over sufficiently. What I'm saying is that anything that humans have ever been capable of or will ever be is indeed "possible." My issue is with the fact that people define the realm of the possible in a way that lends itself to the idea of transcending that realm. So people will say, "so and so did the impossible" but if it was impossible, it wouldn't have happened. To make it more analytically explicit, Sartre has a concept of a "field of possibles" in his book on methods that looks at (im)possibility as a subjective artifact that structures people's actions. So what is subjectively regarded as possible is always a subset of what is objectively possible.

    Not true. Resistance in any form is always generative of some effect.

    Every time I read you quote this, it seems like you are more interested in the effect of talking about God in this way than the actual meaning. Maybe I am misreading you, though.

    Again, I have not explained my point adequately. Universe is a term that refers to everything. "Everything" cannot have an outside because if it would then it wouldn't be "everything" but "some things" or "most things." "Everything" must literally contain the set of EVERY-THING or it is not "everything." I.e. if there is something outside "the universe" then it would be a sub-set of the universe and not the universe itself. "Universe" refers to the set that does not exclude anything.

    Matter/energy cannot be created or destroyed, only transformed. That is the law of conservation of matter-energy.

    If the universe includes the set of all possible precursors to everything, whatever created it would be part of it and therefore you could say it created itself.

    I follow your logic, but the implications you're alluding to about God are not theologically productive, imo. If you want to understand God, physics is not the place to begin. Physics only leads you to awe of vastness, which leads to the least possible intimacy with divinity. Scripture or Jungian psychology or even some philosophy would work more in your favor, theologically, I think. Theology is really more about understanding man's role [sic] in his knowledge of the universe and life purpose, not so much the knowledge of the universe itself. If you want to understand God, you should ask why humans seek knowledge, not what knowledge they have.
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