Results are out! Find what you need...fast. Get quick advice or join the chat
Hey there Sign in to join this conversationNew here? Join for free

could the universe be finite in size but still infinite

Announcements Posted on
Live webchat: What’s new, what’s changed? 30-09-2014
Complete this short survey for a chance to win an iPad mini! 22-09-2014
    • Thread Starter
    • 1 follower
    Offline

    ReputationRep:
    what im suggesting is that the universe is finite, its still really, really,really,really,really big but there is finite matter,space energey ect but the universe has a way of recycling itself, so that every possible outcome has already happened.

    Name one thing in nature which isnt reused again and again? new planets and stars are remade out of dead ones. what if the universe was like this.
    • 6 followers
    Offline

    ReputationRep:
    There isn't anything, energy is never lost, just transformed and reused. The death of stars produces more matter I think (not an astrophysicist). I guess there is a finite amount of matter but perhaps the universe is increasing at such a rate that it would be impossible to get outside it? Just pure guessing.
    • 4 followers
    Offline

    ReputationRep:
    The universe expands, and at an accelerating rate (according to research that won the 2011 nobel prize), so as far as we will ever experience, the universe may be considered infinite in size (this is not unreasonable, since any calculation of size would be wrong, and an underestimate in an infinitesimally small amount of time). However, basically everything else is finite within the universe. The universe is rife with symmetry, and according to Noether's theorem, where there is symmetry, a conservation law is brought along - and gives the reason why the total momentum, energy, and so on and so forth in the universe is a conserved, unchanging, finite quantity.

    edit: While I'm at it - since I sometimes see "what have women done?" threads every so often - Emmy Noether made great contributions to mathematics and theoretical physics, and this is a biggie.
    • 1 follower
    Offline

    ReputationRep:
    What exactly are you postulating is infinite?
    • 10 followers
    Offline

    ReputationRep:
    Can a question be stupid, and not stupid at the same time?
    • 2 followers
    Offline

    ReputationRep:
    Physics to the rescue!

    (Original post by FireGarden)
    The universe expands, and at an accelerating rate (according to research that won the 2011 nobel prize), so as far as we will ever experience, the universe may be considered infinite in size (this is not unreasonable, since any calculation of size would be wrong, and an underestimate in an infinitesimally small amount of time).
    Not really. At least if you believe in a Big Bang. Simple thinking: if in the beginning the whole Universe was concentrated in one point, today the Universe cannot have a radius larger than the speed of light times its age. Otherwise something would have travelled faster than light, which would raise a conflict with relativity.

    (Original post by ednut)
    Name one thing in nature which isnt reused again and again?
    Heat. If you can do that to heat you're sure to win a Nobel Prize for forever changing the second law of thermodynamics.

    (Original post by FireGarden)
    edit: While I'm at it - since I sometimes see "what have women done?" threads every so often - Emmy Noether made great contributions to mathematics and theoretical physics, and this is a biggie.
    Hell Yeah!
    • 0 followers
    Offline

    ReputationRep:
    As I said in my energy post. There is either infinite or nothing.

    The universe is either infinite or nothing at all which in a sense both are the exact same thing.

    If you are saying the finite energy exists then the opposite of finite has to exist. Think about it. How do you know how much black paint there is on a white wall? Because you contrast the black with the white. So if you identify a finite amount of X, then you have also identified that something else is taking up the amount that X is not taken up.

    You know a half glass of water is half empty because 'empty' takes up the half the glass that does not have water.

    Whatever is finite exists in the backdrop of infinite/nothing or the infinite nothingness
    • 4 followers
    Offline

    ReputationRep:
    (Original post by viriol)
    Physics to the rescue!



    Not really. At least if you believe in a Big Bang. Simple thinking: if in the beginning the whole Universe was concentrated in one point, today the Universe cannot have a radius larger than the speed of light times its age. Otherwise something would have travelled faster than light, which would raise a conflict with relativity.
    Yes really. http://news.nationalgeographic.com/n...nergy-science/ . I study physics :P
    • 2 followers
    Offline

    ReputationRep:
    No to your question.

    According to what we know so far, the Universe is more likely infinite but we still have a way to go before we know for certain.

    How we judge if the universe is infinite or finite; we are following the dimensions set out by special relativity; we postulate that the equations of general relativity can be solved to show that a finite universe must have a larger density of matter and energy inside it than an infinite universe would have. There is a certain critical density that determines the overall structure of the universe. If the density of the universe is lower than this value, the universe must be infinite, whereas a greater density would indicate a finite universe. These two cases are referred to as an open and closed universe respectively. The critical density is about 10-29 g/cm3, which is equivalent to about five hydrogen atoms per cubic meter.

    The main problem our theories have, and why there is this halt in the physics paradigm is due to Planck density, and our current understanding of the big bang, couple that with the theoretical equation of singularity in every galaxy due to black holes.

    But to your question; No.
    • 8 followers
    Offline

    ReputationRep:
    no.

    finite /=/ infinite :facepalm2:
    • 1 follower
    Offline

    ReputationRep:
    From the little knowledge I have, I believe that the Universe can be infinite in three dimensions. The accelerating universe theory does not state that the universe is getting bigger so to speak; does it not only say that the space between the galaxies is getting larger?

    To make this infinity plausible to human conception, think of a two dimensional world. Say the whole universe was on the surface on a balloon, to an observer on the balloon their space is infinite in two dimensions; however us three dimensional beings can obviously see that it is finite. Perhaps this is a reflection of us and our universe; if string theory ever leads to anything this may be proved. However for now it is just a theory.

    Mark
    • 2 followers
    Offline

    ReputationRep:
    (Original post by ednut)
    what im suggesting is that the universe is finite, its still really, really,really,really,really big but there is finite matter,space energey ect but the universe has a way of recycling itself, so that every possible outcome has already happened.

    Name one thing in nature which isnt reused again and again? new planets and stars are remade out of dead ones. what if the universe was like this.
    It's sheer nonsense to say a thing is SIMULTANEOUSLY finite and infinite. One of the first rules of logic is that a thing CANNOT simultaneously be and not be. And also that a thing is itself.

    You're starting off on the wrong foot here and therefore one cannot expect a good outcome.

    Besides, what are you referring to as "the universe"? When only the Singularity existed - AND NOTHING ELSE - was it still the universe or something else? Aren't you here just trying to cling to YOUR notion of "the universe" rather than what it actually is?

    Anyway, cycles CANNOT initiate themselves as ANY mathematician or physicist will tell you - if they're choosing to think LOGICALLY rather than emotionally. I'm also happy to explain this to you - if you wish. Ever since the Big Bang theory, one can't help but notice that atheists have been very depressed since it has become clear, contrary to their fondest hopes, that Matter is NOT eternal after all - but a mere PRODUCT!
    • 2 followers
    Offline

    ReputationRep:
    (Original post by String.)
    From the little knowledge I have, I believe that the Universe can be infinite in three dimensions. The accelerating universe theory does not state that the universe is getting bigger so to speak; does it not only say that the space between the galaxies is getting larger?

    To make this infinity plausible to human conception, think of a two dimensional world. Say the whole universe was on the surface on a balloon, to an observer on the balloon their space is infinite in two dimensions; however us three dimensional beings can obviously see that it is finite. Perhaps this is a reflection of us and our universe; if string theory ever leads to anything this may be proved. However for now it is just a theory.

    Mark
    You're confusing finite with bounded - and infinite with unbounded! They're NOT the same thing at all! Just because one can travel endlessly round and round the surface of the earth does not mean that one comes to think that it is infinite. I doubt even hamsters regard their treadmills as infinite. And, anyway, the very fact alone that something is of limited dimensionality makes it finite.

    By the way, String Theory is FAR MORE well-established as a theory than Darwinism. It's predictions and explanations are FAR MORE reliable than ANYTHING Darwinism has EVER offered! The only reason why some people still doubt it is DESPERATION - because it points firmly AWAY from materialism.
    • 20 followers
    Offline

    ReputationRep:
    This is a meaningless question because space is a tool used by the mind and not neccesarily something that exists initself.

    If the universe is finite - the co-ordinates of the surface can be taken in respect to a space beyond the surface.
    Theres a similar problem when stating that space is infinite.
    • 10 followers
    Online

    ReputationRep:
    (Original post by Zaki)
    You're confusing finite with bounded - and infinite with unbounded! They're NOT the same thing at all! Just because one can travel endlessly round and round the surface of the earth does not mean that one comes to think that it is infinite. I doubt even hamsters regard their treadmills as infinite. And, anyway, the very fact alone that something is of limited dimensionality makes it finite.

    By the way, String Theory is FAR MORE well-established as a theory than Darwinism. It's predictions and explanations are FAR MORE reliable than ANYTHING Darwinism has EVER offered! The only reason why some people still doubt it is DESPERATION - because it points firmly AWAY from materialism.
    Out of interest, what is your degree subject?
    • 2 followers
    Offline

    ReputationRep:
    I assume the original question is really "can the universe be finite yet unbounded". As finite and infinite appears a bit clunky.

    Not what I consider to be a philosophical question but more to do with the characteristics of the mathematical model used to describe it.

    New matter is not created in supernova, but the matter is recombined into nuclei which cannot be made at the energy levels of conventional fusion reactions in active stars of whatever mass. New matter is not created in white dwarfs or Neutron stars either, the existing matter takes on an unfamiliar form due to quantum degeneracy pressures, but there is a view that black holes can radiate matter due to quantum effects at the event horizon.

    The amount of matter in the universe (density) does not determine whether the universe is finite or infinite, but it does determine whether a finite, yet unbounded, universe will either:

    a) Expand forever.
    b) Stop at some point and then contract.
    c) Expand forever with asymptotic characteristics giving the impression of a steady state.
    • 2 followers
    Offline

    ReputationRep:
    (Original post by Octohedral)
    Out of interest, what is your degree subject?
    What is the relevance of this question to the issue at hand? I mean, you could also ask for the radius of my nostrils but how would that illuminate the issue being discussed? It just clouds it. If I said I was a professor of physics, would that, in an of itself, make my arguments weightier? Of course not! If I said I was a janitor who never got to sixth form, would that make my arguments less valid? Indeed not! Why not deal with my actual arguments rather than trying to distract attention from them?
    • 2 followers
    Offline

    ReputationRep:
    (Original post by Person1001)
    This is a meaningless question because space is a tool used by the mind and not neccesarily something that exists initself.

    If the universe is finite - the co-ordinates of the surface can be taken in respect to a space beyond the surface.
    Theres a similar problem when stating that space is infinite.
    Even tools of the Mind are real though. EVERYTHING is real - EVEN ABSURDITIES! However, not everything is manifest under all conditions. Unfortunately the bad habit of equating manifestation with reality and non-manifestation with unreality is strongly entrenched amongst humanity today. It will lead to NOTHING good!
    • 20 followers
    Offline

    ReputationRep:
    (Original post by Zaki)
    Even tools of the Mind are real though. EVERYTHING is real - EVEN ABSURDITIES! However, not everything is manifest under all conditions. Unfortunately the bad habit of equating manifestation with reality and non-manifestation with unreality is strongly entrenched amongst humanity today. It will lead to NOTHING good!
    Im not claiming space is unreal - I'm just stating that as with time we cannot treat them as things-in-themselves else we get antinomes since all our thought (probably excluding syllogisms) require them to be the case.
    • 7 followers
    Offline

    ReputationRep:
    do you mean it's finite in a scale that is defined as infinite in scale nowadays?

Reply

Submit reply

Register

Thanks for posting! You just need to create an account in order to submit the post
  1. this can't be left blank
    that username has been taken, please choose another Forgotten your password?
  2. this can't be left blank
    this email is already registered. Forgotten your password?
  3. this can't be left blank

    6 characters or longer with both numbers and letters is safer

  4. this can't be left empty
    your full birthday is required
  1. By joining you agree to our Ts and Cs, privacy policy and site rules

  2. Slide to join now Processing…

Updated: March 3, 2012
New on TSR

'Stalking pages' have changed!

Find other uni applicants with University Connect

Article updates
Useful resources
Reputation gems:
You get these gems as you gain rep from other members for making good contributions and giving helpful advice.