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View Poll Results: Are we expanding beyond our escape veloity?

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Thread: Expanding Universe

  1. #1 Expanding Universe 
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    Recently, in fact, only a week or two ago, it was announced that scientists had finally proven that the universe is, in fact, expanding.
    There was always very influencial speculation that this was so, however, some in the scientific community attributed the apparent expansion only to the rotation of the universe. In short, some believed that the universe was stationary and that rotation was what caused the "red-shift' readings to indicate that it was expanding.

    We now have irrefutable confirmation of this, so now, we have another, very important question to ask.

    Is it expanding past it's escape velocity? Is the expansion of our universe fast enough to escape gravity's pull? If this is so, then we would grow further and further apart from the rest of the universe forever, as opposed to gravity returning us all to a "singularity" (uuh I hate that singularity) much like a thrown tennis ball returns to the ground.

    The problem is, we can never know this In order to determine our universes escape velocity, we need to know how much matter there is in it. Again, the "dark matter/dark energy" conundrum returns here. Only about 70% of the universes matter has been accounted for as of yet, so we cannot approximate our escape velocity.

    What are your thoughts? Will we keep expanding forever, or will the gravity of all the matter in the universe eventually overcome expansion, bringing us all closer together until we become a singularity, and the Big Bang once again repeats itself?


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  3. #2  
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    In my younger days when I first picked up a book detailing Einstein's rubbermat analogy of spacetime I formulated this hypothesis regarding expansion. Its good for a laugh.

    Let's say every galaxy sits at the bottom of a gravity well it has created on a gigantic static(maintains its shape) balloonlike sphere, the surface of which is spacetime but comparable to a stretchy membrane of some sort. As the burdgeoning black hole(galaxy) swallows more matter, it becomes denser thus creating a deeper well. Massless light cannot dent this membrane but can travel along its surface. Gravity is also restricted. It's force only exerting itself along or outside of the membrane's surface also. As the wells deepen the light between galaxies has to travel farther and farther and the pull of gravity between galaxies becomes weaker resulting in the expansion illusion when in fact everything is coming very nearly all together at some central point.

    But in all honesty if the universe is infinite then there is no hope, not that it matters, for a big crunch.


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  4. #3  
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    Since the rate of expansion has been determined to be increasing, we can reasonably presume that the expansion will continue for ever.

    Nothing is irrefutable, including this statement.
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  5. #4 universal expansion 
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    It might not be the scientific way of looking at it but I think of the universe as we presently know it as a growing universe contained within a larger universe, which is contained with another even larger universe, within another and another, etc. on into infinity. And it's all still growing.

    When I was just a child I once had it explained to me this way by an insane man who was convinced he was god (and for all I know, maybe he was.) He held up his finger to me and told me to look at it through a magnifying glass and said "look at one tiny open pore on the skin of my fingertip. Now imagine that pore is a universe containing all the galaxies and solar systems that we already know of. See all the other millions of pores, each one as a separate universe. And all those pores are part of a greater whole that makes up this man's body. And this man's body is as a single atom on the face of this earth, and this earth is as a single atom contained at the end of the spiral arm of the galaxy that contains our solar system. Now imagine that our galaxy is as a single pore on the fingertip of a greater universe which is only the fingertip of another one."

    It was easier for me to relate to this concept when I started studying growing crystals under microscopes and discovered entire alien universes within them.

    See some cool images (micrographs) of microscopic crystals that are growing and expanding in an orderly fashion and imagine that this first one, the single grain of sand, is just one universe within many, and that the crystals growing within the grain of sand are other universes.

    multiple crystals growing within a single grain of sand:
    http://www.magma.ca/~rel/mfc/images/sand/packed.jpg

    microscopic space dust- olivine a.k.a. peridot - The NASA telescope's infrared eyes have for the first time detected clumps of microscopic dust grains and tiny crystals orbiting five brown dwarfs. These clumps and crystals are thought to collide and further lump together to eventually make planets. Similar materials are seen in planet-forming regions around stars and in comets, the remnants of our own solar system's construction. http://www.nasa.gov/images/content/1...048-browse.jpg

    some kind of liquid crystal: http://142.31.52.6/Unit1/images/01crystl.jpg
    another kind of crystal: http://images.picturequest.com/commo...8/22579865.jpg
    and another @ 200X mag: http://labs.sci.qut.edu.au/minerals/...quartzms13.jpg
    and 4 more 200X: http://www.mineralsocal.org/micro/images/micromin.gif

    a crystal and 2 diatoms: http://www.msscweb.org/images/homepage/crystal%201.jpg

    Transmitted polarized light micrograph of a high density liquid crystalline DNA phase.
    http://micro.magnet.fsu.edu/publicat.../dnaliquid.jpg

    Microscopic observation of Side Chain-Polymer Liquid Crystal
    http://www.gsst.kumamoto-u.ac.jp/img...he_mat_1_l.jpg

    Microscopic Views of 2 Meteorites
    http://www.photovault.com/Link/Unive...AV01P01_18.jpg
    click on the square to enlarge image of this meteorite even more
    http://www.psrd.hawaii.edu/WebImg/D'Orbigny.jpg

    microscopic oil-mineral aggregations (OMA). OMA is a process where oil droplets and sediment grains naturally adhere to one another, providing an opportunity for naturally-occurring bacteria to consume and, thus, biodegrade the oil.
    http://www.dfo-mpo.gc.ca/science/coo...er_021_Oma.jpg

    micrograph of rock wool:
    http://www.aichi-sangyo.co.jp/englis...s/mineral4.gif

    aragonite: http://www.sciencenews.org/articles/...f4317_1708.jpg

    a single crystal of salt: http://www.chem.cornell.edu/sl137/Pictures.dir/salt.jpg

    microscopic snowflake crystal: http://www.chem.cornell.edu/sl137/Pictures.dir/snow.jpg

    frozen sea-ice - called frazil crystals http://nsidc.org/seaice/images/frazil2.jpg

    Paracetamol crystals: http://www.wack.ch/fame/afc1/pic6/afc614b.jpg

    Tartaric acid crystals: http://www.wack.ch/fame/afc1/pic6/afc623b.jpg

    microscopic dolomite: http://www.osomin.com/ra9.jpg

    If these are all little universes growing in an orderly fashion right here on our tiny little ball of earth then why can't the same thing be happening on a bigger scale - out there? I believe there is perfect order in the universes and that their scale and rate of growth is beyond our imagination.

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  6. #5  
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    Quote Originally Posted by Joshua Violinist
    Recently... only a week or two ago... scientists ... [proved] the universe is... expanding.
    Since about the 1920s. When Edwin Hubble found galaxies were moving away from us, and the further away the faster they were moving, it was pretty well clinched.
    Quote Originally Posted by Joshua Violinist
    ... always ... speculation that this was so, ... some in the scientific community attributed the apparent expansion only to the rotation of the universe.
    Would you care to name one of the scientific community who thought the universe was rotating? Since the universe is all there is, any movement of the universe as a whole is meaningless. In other words, relative to what is the Universe rotating? And just for the tally books, what was the ‘... only a week or so ...’ announcement? I keep an eye on this sort of thing and I didn’t see it.
    Quote Originally Posted by Joshua Violinist
    ... some believed ... universe ...stationary ... rotation ... caused the "red-shift' readings to indicate that it was expanding.
    Could you name just one of those you’ve just referenced? I’ve read all sorts of stuff on theories of the Universe and I’ve never seen this.
    Quote Originally Posted by Joshua Violinist
    ... irrefutable confirmation of this...another, very important question to ask.
    Okay... I’d really like to know about the irrefutable confirmation.
    Quote Originally Posted by Joshua Violinist
    Is it expanding past it's escape velocity? Is the expansion of our universe fast enough to escape gravity's pull?
    Escape Velocity? Escape from what? The Universe isn’t going to escape from itself. This is sort of like asking if your body can escape from your body.
    Quote Originally Posted by Joshua Violinist
    If this is so, then we would grow further and further apart from the rest of the universe forever, as opposed to gravity returning us all to a "singularity" (uuh I hate that singularity) much like a thrown tennis ball returns to the ground.
    Oh, hold the phone... Josh, that is not ‘escape velocity’. You’re talking about the continued expansion of the Universe question. Josh, I hate to break this to you, but this question has been discussed and argued since – uh – the 1920s or so as well. In fact, since Hubble discovered the expansion.

    And what do you have against the singularity? It’s a very fine and perfectly honorable singularity.

    Quote Originally Posted by Joshua Violinist
    The problem is, we can never know this.
    Josh, you’ve overstated this again. Yes, we can know. We do not know now, but we can know. This isn’t like the Heisenberg Uncertainty Principle, okay?
    Quote Originally Posted by Joshua Violinist
    In order to determine our universes escape velocity, we need to know how much matter there is in it.
    Actually, we need to know how much ‘mass’ the Universe contains. Not ‘matter’, but ‘mass’.

    Quote Originally Posted by Joshua Violinist
    Again, the "dark matter/dark energy" conundrum returns here. Only about 70% of the universes matter has been accounted for as of yet, so we cannot approximate our escape velocity.
    Yeah, that’s being investigated, and has been for some time.

    Josh, I probably seem harsh and very nit-picky about your post. I am being so intentionally, and for a couple of reasons.

    1. How one looks at a problem has a great impact on how one solves a problem. If one is intent on seeing ‘matter’, one may or may not find the ‘mass’, f’rinstance.

    2. You don’t seem to be very familiar with this line of inquiry. May I suggest you do some reading on the subject? Among other books, Hawking’s A Brief History of Time and Greene’s Fabric of the Cosmos and The Elegant Universe are excellent starters. I suggest you go to the local library and read everything you can find in the Astronomy-Cosmology section. That’s a lot of reading, but it will provide a solid foundation for these types of discussions.

    Quote Originally Posted by Joshua Violinist
    What are your thoughts? Will we keep expanding forever, or will the gravity of all the matter in the universe eventually overcome expansion, bringing us all closer together until we become a singularity, and the Big Bang once again repeats itself?
    I’ve been reading and discussing this for twenty years at least. Here are the basic options:

    More Than Enough Mass. At some point, the gravity of all the mass in the Universe finally overcomes the initial expansion of the Bang and the expansion stops... then all the bits start falling back in on themselves in what has been waggishly called the “Big Crunch”, or, in a moment of silliness, the “Gnab Gib” (Big Bang backwards). I’ve heard it claimed this will initiate another Big Bang, but the mechanism to reset all the entropy counters has not been identified.

    Just Enough Mass. At some point the gravity of all the mass in the Universe balances out the force of expansion and the Universe stops and holds at some final size.

    Not Enough Mass. There just isn’t enough mass to generate the gravity to stop the expansion. The Universe keeps expanding forever.
    Please note, in the second and third options, at some point, all the usable energy in the Universe is lost to entropy. This is called ‘Heat Death’ and nothing more will transpire.

    Any way one looks at it, the Universe will only sustain life for a finite (although enormously long) period of time. The Universe, as we know it as a sustainer of life, will end. However, the Universe will easily outlive the Earth, so I’m not sweating it.

    My apologies for any typos or mispelled words. I don't have my reading glasses with me, and this print is awfully small for these old eyes.
    The universe is a real place. However, you can't see it, you have to imagine it. Like it or not, God designed, built and sustains the Universe. Deal with it.
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  7. #6  
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    Well, well, while your criticism is undoubtably welcomed and beneficial, and you are probably correct.

    In all honesty, I have absolutely no background in physics, yet. I cannot take physics for another few years. Science is, for me, a congregation of all the subjects.

    On that note, I would like to point out that I am very intrigued by the feild, particularily string theory. I have read Greenes book, as have I read Stephen Hawkings, and, while it did give me a base knowledge, it was the brilliant analogies which stuck with me.

    If not to correct myself, then to apease you, when I referred to the "universe" I was not referring to "space" but rather all the matter in "space."

    I like to ponder questions such as this for my own amusment. I do not, nor do I claim to, have a vast knowledge of the subject.

    When you questioned the assumption that a few scientists attributed the red shift readings to the universes rotation, I meant the matter. Of course "space" cannot rotate! The matter suspended in space, however, can. Our galaxy rotates, as does the matter in space. If you measure the distance from point A in a spinning entity, to point B in a seperate one, it will appear to move further away. Scientists (no, I cannot give names, I don't know them.) had always had an argument, however feeble, which prevented the "expanding universe" theory (now fact) from being ruled supreme.

    Again, in closing, I do not mind the nit picking, as we all learn from our mistakes, but it almost seems like you tried to pick me apart. You obviously know alot more than I about this, I realize and welcome that, but could you not have added your insights without blowing my post to shreads ? In any case, I will follow your posts with aprehension! (although, apparently misinformed aprehension ) :-D
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  8. #7  
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    Relax, Josh.

    Okay, we agree the Universe itself does not rotate. Nor does the matter therein - here's why:

    Let's pretend the universe is the interior of a sphere. (This is a popular notion, is very wrong and is probably counterproductive - that is, it prevents people from understanding what the universe is really.) However, if all matter 'rotated' uniformly within the interior, how would anyone know? There is no baseline or grid relative to movement to compare.

    All the matter in the Universe is moving. Yes, most everything is moving relative to something else. Our galaxy is moving toward the "Great Attractor"; our system is rotating relative to other galaxies; our Earth is rotating around our Sun and our Earth is rotating on its axis relative to sideral observation. Additionally, space is expanding, therefore, in some degree, all things are moving 'apart'. More or less. Our galaxy is scheduled to pass through the Andromeda galaxy in another gazillion years or so.

    I think the disagreement about expansion was the Steady State argument of the 1940s and 1950s. The argument was not the universe was expanding, but that it had an origin time. Or it could be you're thinking of something else.

    Yes, it's a great, interesting and fun field. I just wish I could have made a living doing this. Oh, well.

    Forgive me if I seem too nit-picky. I do tend to be pedantic at times. Still, sometimes one just has to say, "That's wrong." I mean, there's just so many ways to say that gently.

    Anyway, what is your take on the future of the Universe? Expanding forever or not?
    The universe is a real place. However, you can't see it, you have to imagine it. Like it or not, God designed, built and sustains the Universe. Deal with it.
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  9. #8 Re: Expanding Universe 
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    Quote Originally Posted by Joshua Violinist

    What are your thoughts? Will we keep expanding forever, or will the gravity of all the matter in the universe eventually overcome expansion, bringing us all closer together until we become a singularity, and the Big Bang once again repeats itself?
    It is not possible to answer your question with our present database. We need to figure out how much matter dose really exist in our universe. Only then we can answer your question

    I wish big bang could repeat again.
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  10. #9 Re: Expanding Universe 
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    Quote Originally Posted by anandsatya
    I wish big bang could repeat again.
    Wouldn't that be a little inconvenient?
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  11. #10  
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    if 30% of the matter in the universe is unaccounted for how do we know how much of it there is? How do we know we found 70% and not 3% or 50% Accounted for matter + unaccounted for matter = total matter in the universe. How can we possibly know that the accounted for matter is 70% of the total?
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  12. #11  
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    Looking through my telescope the other night at galaxies M81 and M82 in the same view I had to wonder, why would a big bang end up with these groups of galaxies with nothing in between. What central forces pulled stars (or whatever) together in these neat groups we call galaxies? If it was forever expanding why would all the mater not be pushed outward, in the case of the spinning galaxies the mater is travel at some point in a backwards direction. Then I also have to ask, why are galaxies for the most part flat and not spherical. Yet, some are. Go figure.
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  13. #12  
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    Just some food for thought; What if the universe never escaped the event horizon of the Big Bang Singlarity? Then the expansion/contraction of the universe as detected by those within the event horizon would be the same as the data we now have. How do we know that we are in an expanding universe, as opposed to being stuck in event horizon of the Big Bang Singlarity? Strange thoughts I agree, but I can not think of a way to verfiy which case is true, any ideas?
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  14. #13  
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    Cosmology has become too theoretical.
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  15. #14  
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    Well Archie; what do you mean by: The universe is a real place. However, you can't see it, you have to imagine it. Like it or not, God designed, built and sustains the Universe. Deal with it.

    What do you mean by Real? If you could define it for me that would help me an awful lot since I have dealt with questions about reality for a long time now.
    Also, is your remark about God supposed to be taken as a scientific one or just a belief, because in the latter case if I don't like it I don't have to deal with it.
    Do you have any speculations on why God would need to create a Universe in the first place?
    Don't you think that (since you are suggesting the same thing to others) a view of this kind limits your own ways of looking at things, and also the "answers" you eventually find?
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  16. #15  
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    Quote Originally Posted by rrushius
    Well Archie; what do you mean by: The universe is a real place. However, you can't see it, you have to imagine it. Like it or not, God designed, built and sustains the Universe. Deal with it.
    This is actually a quote from an artist named Alexander Calder. Actually, it’s a misquote (I looked it up).
    The universe is real but you can't see it. You have to imagine it. Once you imagine it, you can be realistic about reproducing it. (Alexander Calder)
    Quote Originally Posted by rrushius
    What do you mean by Real?
    Can you break your toe kicking a rock? That’s real.
    Quote Originally Posted by rrushius
    If you could define it for me that would help me an awful lot since I have dealt with questions about reality for a long time now.
    Bless you, my son; don’t we all.

    Reality… reality… reality… I used to know… Reality is that which has actual being. I’m not sure that’s any more useful. Reality is what is there even if you ignore it, or don’t know about it. Very profound, not very useful.

    What I mean to say is this; it seems the Universe is really here and we’re really in it. We make experiments and calculate values and fall in love and pay bills and so on. There’s no point in wondering if this is all an illusion. If I don’t eat, I get hungry. Maybe I just fantasize I don’t eat and the hunger pains are illusions, but they are pretty convincing illusions and I don’t like them.

    However, we cannot ‘see’ the universe. We can’t even draw a picture of it.

    We can draw a flat (paper) picture of the world. We usually call these pictures maps. We know the world is a sphere, more or less, but a flat map is handier to fold up and put in a drawer. But we can reasonably represent the surface of the world on a paper because the surface of the world is two-dimensional. There’s only two axes, ‘North-South’ and ‘East-West’. Now, the surface of a sphere is unbounded, but a paper has edges. Well, we know the ‘top’ and ‘bottom’ of the map are actually points; while the ‘sides’ actually connect with each other. If we run off the ‘left side’, we reappear on the ‘right side’.

    Not so with the universe. Heck, we really can’t even show the solar system on a flat piece of paper. One of the planets (Neptune, I think), and most of the comets, are not in the same plane of rotation. We can come close. We just superimpose the three dimensional nature of the solar system onto a two dimensional representation, and pretend they’re all in the same plane.

    When we get to the galaxy, we’re really in a quandary. The galaxy is really a three dimensional construct and no way around it. Were we to ‘map’ the three dimensional galaxy on a two dimensional paper, we’d have so many stars overlapping in places – especially near the center – we couldn’t label them all. We can sort of portray the galaxy in a pseudo-three dimensional drawing. The galaxy is a flattened disk sort of thing which lumps up in the middle and feathers out on the edges.

    Now, here is the point so far; we know the outside shapes of the Earth, the Solar System and our Galaxy. We have not a clue as to the shape of the Universe. We can’t see it from the outside. As far as we know, there is no ‘outside’ from which to see it.

    But we can try. The Universe is a three dimensional (not counting time or those possibly little ‘rolled up’ dimensions) construct. Much like a big room. So imagine a big room. Now imagine the ceiling is open and extends up – into the floor. Yeah, somehow it curves around and the floor – which is bottomless – blends into the ceiling. The West wall also extends out and curves around to join the East wall. And the North and South walls are really not there either, but curve around to meet up to each other…

    That is the shape of the Universe, as far as we can tell. But we can’t really draw a picture of it.

    Quote Originally Posted by rrushius
    Also, is your remark about God supposed to be taken as a scientific one or just a belief, because in the latter case if I don't like it I don't have to deal with it.
    Remember the part about reality being there even if we ignore it or don’t know about it? God is there. And here, for that matter. From a scientific standpoint, God isn’t always needed. For instance, we can use “2 + 2 = 4” without bothering God with it. We don’t have to cite “God says ‘2 + 2 = 4’” in order for the formula to work. Newton’s laws of gravity do not require God to function.

    Of course, if God is Creator and Sustainer of the Universe, those laws only exist because God designed and enacted them. There seems to be doubt in some folks minds about that. There isn’t in mine. And, one way or another, everyone will deal with God. Sooner or later, for better or worse.
    Quote Originally Posted by rrushius
    Do you have any speculations on why God would need to create a Universe in the first place?
    I don’t think ‘need’ is the right word. Does a kangaroo ‘need’ to hop? Does a bee ‘need’ to buzz? Does gold ‘need’ to be heavy? I think God creates because that is what God does.
    Quote Originally Posted by rrushius
    Don't you think that (since you are suggesting the same thing to others) a view of this kind limits your own ways of looking at things, and also the "answers" you eventually find?
    No. Well, I suppose that depends on what you mean by ‘limit’.

    I presume someday you will seek companionship of the opposite sex; perhaps you already have. Do you plan on seeking a hummingbird as a life-partner? Are have you already ‘limited’ yourself to a human partner? Do you feel ‘limited’ in only dating other homo sapiens? (Presuming you’re not a dolphin or Klingon or ‘toon, of course.)

    Answers are 'limited' to what they can be. Solving for the area of a circle will never give a solution of "Tuesday". One can never make a suit of clothing from bubbles (which is why bubble dancers are so popular).

    God gave mankind 'dominion' over the Earth. I think that extends as far as man can reach. Dominion is an old-fashioned word that means control, among other things. So learning about how the Universe - and it's component parts - works is part of what God wants us to do. God isn't threatened by what we can find or find out. God isn't going to be any less God if we do formalize the Grand Unified Field Theory. There is nothing about God that limits me.
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