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Where does new space come from as the universe gets bigger?

  1. Apr 10, 2014 #1
    Greetings,

    How is new space created?

    There was no space before the big bang, correct? And the universe is still getting bigger? So the amount of space is increasing.

    Where did and does it come from? Space is something not nothing correct? It can be stretched, compressed, and curved.

    Is something being converted into space? I heard mention somewhere that gravity was being converted into space.

    Thanks
     
  2. jcsd
  3. Apr 10, 2014 #2
    A common mistake is to apply a physical nature to space. Space is simply volume or distance. the volume is filled with other things such as energy and matter. google metric expansion.
     
  4. Apr 10, 2014 #3
    "google metric expansion."

    I had read that.

    So the countless illustrations of space being warped by mass are incorrect? And the idea that you could travel faster than light by contracting and expanding space? And wormholes shown and described as distorted space. Space is constantly referred to as a fabric. That all indicates space is something.
     
    Last edited: Apr 10, 2014
  5. Apr 10, 2014 #4

    Bandersnatch

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    In your opening post, try and replace every instance of the word "space" with the word "distance". Read the altered text and ask yourself whether it seems sensible to you to ask such questions.

    Space is of course not equivalent to distance, but it is a very similar concept.
     
  6. Apr 10, 2014 #5

    Matterwave

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    The picture of space-time as a "fabric" is an analogy, not to be taken seriously. It has its uses, but must be abandoned when it's no longer useful. Space-time is made up of all the events that take place in it, it is not its own separate entity.
     
  7. Apr 10, 2014 #6
    Well this is big news. As in my last post...scientists are constantly describing it as as a thing not distance. I mean every time cosmology and physics is talked about. I could spend forever citing scientists saying something incorrect about space then, assuming they continue to make the mistakes. I can probably search these forums and find experts doing it. They are then misinforming millions of people. Most science books are wrong. Space is not curved. Mass/gravity does not curve space. Wormholes are not as illustrated. You can't expand and compress space to bypass the speed of light. It is all wrong then.

    I have been trying to understand universe for years based on these endless false statements. Darnit. This changes everything. No I need to reread everything on cosmology, relativity, and quantum physics *without* thinking of space like that. They really screwed up.
     
    Last edited: Apr 10, 2014
  8. Apr 10, 2014 #7

    Bandersnatch

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    I did not write any of that. Why are you saying so?

    Scientists are describing space as space. It's a mathematical concept with certain well-defined properties. It's not a "thing" any more than distance is.
     
  9. Apr 10, 2014 #8

    Matterwave

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    It's not as bad as it seems. People have to use words to describe things to other people. We can't just say to the masses "hey, look at the Einstein field equations - That's spacetime - that's gravity!" because nobody would know what we were talking about. The use of analogies is appropriate where they are appropriate. You don't have to "reread" everything or relearn everything just because you found out a new piece of information. Incorporate this new information into what you know.
     
  10. Apr 10, 2014 #9
    I will begin compiling a list of examples of space described and illustrated as a thing with shape stretched, compressed, curved, twisted. Grids showing space itself as having shape.
     
  11. Apr 10, 2014 #10
    "I will begin compiling a list of examples of space described and illustrated as a thing with shape stretched, compressed, curved, twisted. Grids showing space itself as having shape."

    no need we have all seen them numerous times lol. As mentioned they are a visual aid. To describe GR influences on the energy-mass filling space.

    "According to the general theory of relativity, the geometrical properties of space are not
    independent, but they are determined by matter. Thus we can draw conclusions about the
    geometrical structure of the universe only if we base our considerations on the state of the
    matter as being something that is known."

    Part of the confusion derives from statements like the one I posted, coincidentally that one is from Einstein himself lol. Remember that space itself is simply volume filled with energy/mass. So in a way its more accurate to say that gravity affects the energy/mass contained within space rather than space itself. However cosmologist tend to gloss over that as they expect the public to already understand that. Even a total vacuum has energy. So once there is more volume, that volume will always contain some form of energy potential or matter. Terms such as space is created or stretched often are in cosmology literature. Its part of the limitations of lanquage. The mathematics itself shows that its simply an increase in volume or distance between two or more points.

    This article shows the geometric aspects in terms of simple distance measures with the pressure relation influences of matter and the cosmological constant.

    https://www.physicsforums.com/showpost.php?p=4697773&postcount=30

    the article is based largely on Barbera Ryden's "Introductory to cosmology"
     
  12. Apr 10, 2014 #11

    Chronos

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    Space is merely the emptiness between objects in the universe. Emptiness has no metric, so it is unbounded.
     
  13. Apr 11, 2014 #12
    define emptiness, even a void has energy density implications in quantum mechanics as the lowest possible energy state. :wink:
     
  14. Apr 11, 2014 #13
    That is completely the opposite of what the general public understands. I am far more scientifically literate and knowledgable than the general public. That quote from Einstein clearly states the opposite. It says space has geometry. That space itself has shape.

    In beginning to complie my list of examples I found further confirmation of physicists currently statng that space in actually a thing like a fabric and not just volume or distance. This raises the concern to me that the problem is that only one of the current views is being represented in the replies in this forum. A dangerous state of affairs. I will seek to determine whether or not this is the case with the following example.

    Are you aware of the physicist, Brian Green, and his books and PBS series'? One of which is titled "The Fabric of the Cosmos" in which one of the questions he addresses is "Is space a human abstraction or a physical entity?". Are you claiming his view is that space is not an actual thing just as you have stated? It is essential that this be made clear. It is my understanding that his view is that space itself actually has shape. That is is something like a fabric. If I am mistaken about that, then my original question was based on false assumptions. If i am correct, it was not and there should be people here who can answer the question. If there are not, this forum is extrmely limited and lacking.
     
    Last edited: Apr 11, 2014
  15. Apr 11, 2014 #14

    bapowell

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    CosmicVoyager -- are you sure you aren't just getting caught up in semantics?

    When we talk about the curvature of space -- we are quite literally referring to its geometry: how points in this space relate to one another. This geometry can be probed empirically -- by measuring physical objects within the universe. For example, the global curvature of the observable universe is measured by looking at the cosmic microwave background: in effect, by drawing a giant triangle through space (the sides being the size of the horizon when the CMB was generated and the distance in space out to when this happened). We then measure the opening angle of this triangle and compare it with that expected from Euclidean trigonometry, given the length of the two sides. If the universe has appreciable curvature, we expect that the angle will not follow the Euclidean rule. In what sense then, is space not curved?

    Note that this is different from saying that space is a material thing, like a "fabric". (Yes, shame on Brian Greene for putting this into people's heads.)
     
    Last edited: Apr 11, 2014
  16. Apr 11, 2014 #15

    Bandersnatch

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    This objection is similar to saying that many scientists refer to the universe as an expanding balloon in their public outreach book and talks, and then complaining that they are misleading the public by not teaching the 'alternative theory' that the universe is not in fact a balloon, or that actual scientists dogmatically reject the 'balloonness' of the universe instead of giving it equal time in their work.

    It's been said many times that using the word 'fabric' is an analogy. A convenient shorthand for visualising some properties of space, exactly because talking about space having geometry, being stretched and curved, flies over most people's heads.

    You're presenting a false dillema: either space is made of something(fabric, whatever), or it is not curved, stretched etc.
    There is nothing contradictory in saying that something can have a shape and not be a 'thing'. An orbit has got a shape, a bullet's trajectory has got a shape, a galactic plane has got a shape. Borders between countries have got a shape.
    These are all not made of anything either.

    So, no, space is not made of fabric, dough nor rubber. Yes, it does curve, stretch etc.
     
  17. Apr 11, 2014 #16

    Chronos

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    The concept of zero point energy implies empty space has intrinsic 'properties'. This has captured the imagination of the lay public, and inspired more than a few cranks to make a leap of faith off the bridge of reality into an ocean of ignorance. The thermos bottle is a wonderful demonstration of the 'properties' of empty space. It does not conduct heat, yet occupies volume. The vacuum, is however, very accommodating to fields as it neither impedes or amplifies their propagation in any meaningful sense. A magnet place inside a thermos will still attract iron filings external to the container. The magnetic field is unaffected by the vacuum layer, it is only attenuated by distance interposed between the field source. Would that inspire an argument that distance has intrinsic properties? Nothing is nothing, and the supply of nothing in the universe is mathematically unlimited.
     
  18. Apr 11, 2014 #17
    space is a dynamic thingy? It is modeled on 2 accounts GR and QM. If combined we have Curved Space Vacuum or something.. I hope it wouldn't end up in a hole argument.. Just my 2 cents.^^
     
    Last edited: Apr 12, 2014
  19. Apr 11, 2014 #18
    I'm sorry Chronos this time you lost me lol.

    Your example shows that due to no impediment, there is in fact energy present in the vacuum region. The source may be your magnet but it is present in that region. In every unit of volume of space there is always a pressure value. Pressure has energy potential. Whether or not you describe that truism via quantum or classical means its no less true. I do however agree that far too much mysticism oft gets implied by that simple fact.
     
  20. Apr 11, 2014 #19
    after the big bang

    according to standard inflation theory the universe began with about 25 kilograms of matter
    before inflation. the inflation of space seems to have warped matter and it increased the mass of the universe exponentially. can somebody explain that? why EXPANSION OF SPACE TIME WOULD INCREASE THE AMOUNT OF MATTER IN THE UNIVERSE?
     
  21. Apr 11, 2014 #20

    Drakkith

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    Can you provide a link to this? I've never heard this before.
     
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