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Why is there space? Why isn't the universe just one big ball of infinitely matter?

  1. Dec 9, 2011 #1
    Ok this may seem almost silly and childish but...

    Why isn't everything just clumped together? Why is there space between things? Why isn't the universe just one big planet of matter going from more to less dense if gravity makes things attract each other? Why are there planets and space? Why is there space between things? Why would anything ever break apart? Fundamentally, wouldn't we think that "mass" attracts more mass.. or I like to think outside the box, and say that gravity attracts more gravity.. so wouldn't things would just start sticking together, or at least be on that path?
     
  2. jcsd
  3. Dec 9, 2011 #2
    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    the big bang was a really really BIG bang
     
  4. Dec 9, 2011 #3
    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    ok the big bang or the big expansion.. What was that force????? What was the force behind the big bang?
     
  5. Dec 9, 2011 #4
    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    As far as sticking together goes I think you mean particles, atoms, planets and galaxies right?
     
  6. Dec 9, 2011 #5
    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    Yes all matter.. matter attracts other matter right? Isn't that what gravity is?
     
  7. Dec 9, 2011 #6
    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    Well I think it was god but idk its called a singularity cause the laws of physics break down and no one can really say what caused it.
     
  8. Dec 9, 2011 #7
    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    Ok i am no expert but I will explain the best i can. Matter attracts matter (which is gravity) Gravity is the fabric of our universe creating space and time. After the big bang energy began to convert into matter and matter started forming sub particles and particles and whatnot. Atoms are held together by forces stronger than gravity (strong force, electromagnitism, weak force) thats why everything doesnt just merge into one dense ball-o-matter. There is space because matter is being repelled from eachother from not only the big bang but also from space continously being "created" between galaxies by something called dark matter. Also inertia prevents objects from simply being pulled directly towards one another causing orbits. I hope this helped
     
  9. Dec 9, 2011 #8
    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    Could it be that there is a ying to gravity's yang? That for all the pull of gravity there's an equal push somewhere in the universe as witnessed by the ever expanding universe? We think of gravity classically as a one way street with no antigravity (even our word anti-gravity is just "lack" of gravity). But perhaps if we could "step back" and look at the universe, for all the pulling of things together there is an equal push. Like a tug of war or a scale? I'm no rocket scientist or have a Master's in physics, but could it be that we got the idea of gravity wrong?

    God? As in a huge person that just blasted things apart with his mighty war axe? God is even harder to comprehend than science, and there are laws in the universe that should help us truly figure out everything. I'm just saying maybe someone needs to rethink the law of gravity. Again, I'm just trying to think outside of the box and I don't want to offend.. and it's not like I'm explaining things by quantum mechanics, uncertainty, gluons, and gravitons, and a singularity that decided to explode one day, I find that even more disturbing.
     
  10. Dec 9, 2011 #9
    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    That does help.. especially the idea of it all starting as energy.. I'm going to think some more. Thanks.
     
  11. Dec 9, 2011 #10
    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    I completely agree with you, maybe the key lies at understanding singularities. Maybe just as many galaxies are made up of anti-matter as matter. I dont really believe in dark matter or dark energy but then again what the hell do I know. The one thing you can truly count on knowing is that you know nothing.
     
  12. Dec 9, 2011 #11

    Drakkith

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    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    After the beginning of the universe it was much much denser than it is today. So you might think that it should all just clump together in one big ball. And in a way it did, that's what star, galaxies, planets and such are. But the problem is that to clump together it has to move closer together, thus leaving behind a void. Due to tiny differences in density in the beginning of the universe, some parts were slightly more dense than other parts. These parts were the ones that "collapsed", while the parts that were less dense on average were the areas that became voids.
     
  13. Dec 9, 2011 #12
    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    Ok Drakkith, that makes some sense. You're giving me a visual now.. I'm imaging the beginning of the universe like a table with sand scattered evenly (all the matter). The grains of sand start to join with other grains... leaving behind "space". But still... ultimately all the sand would want to make one big ball as it went from a grain, to 2 grains, to 4, to 8. The "planets", these masses would want to slam into other planets.. but ut oh.. this thing called an orbit started to exist.. having things be trapped in between the gravitational pull and what? the motion or something?. .. So the motion when the thing 1 is being pulled into a bigger thing 2 causes thing 1 to get stuck in an orbit.. or it wouldn't survive and it would become part of big thing 2. Ah, I think it's starting to make sense to me.
     
  14. Dec 9, 2011 #13
    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    But everything had to be moving, or expaning... which is the constant state of the universe after all.
     
  15. Dec 9, 2011 #14

    Drakkith

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    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    The closest thing to what you are referring to is Dark Energy or the cosmological constant. And while our understanding of gravity might be missing something, it is far from wrong. The current model of gravity allows us to make extremely precise predictions and it has been observed to match observations on a universal scale.

    That's the problem. To accurately describe something such as gravity you would need to come up with a theory that matches observations just as those theories do. And the big bang was not a singularity that "exploded". It is simply the universe expanding from a dense state to a less dense state.

    Whether you believe in dark matter and dark energy is irrelevant, but understandeable. It can be difficult. The fact is that the models that best fit the observations involve dark matter and dark energy. There ARE alternatives, however these are even more problematic.
     
  16. Dec 9, 2011 #15

    Drakkith

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    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    I don't know what you want to hear. It is simply a consequence of the laws of nature that it works that way.

    The universe was, and is, expanding.
     
  17. Dec 9, 2011 #16
    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    Thanks Drakkith. I'm way too uneducated to have a debate, I'm clearly expressing things based more on "feelings" and my own observations than knowledge. Yet I am doing a lot of research and learning a lot about physics and electricity, but it's only been a month. Perhaps in a year or two's time I can have an educated discussion with you based on prized physicist observations and calculations, which at my level now I can barely understand the F= (G*m1*m2)/r2 formula, let alone how they calculate planetary landings in astrophysics. I'm still figuring out how they can calculate the mass of a planet, and what mass even is =p. But again thanks for the patient answer and teaching me a few things.
     
  18. Dec 9, 2011 #17
    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    Exactly. I wasn't being sarcastic. Just figuring things out for myself. It makes sense to me now.
     
  19. Dec 10, 2011 #18
    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    I don't know, and as far as I know no one else does either. Why did the Universe expand at all? Why didn't it happily remain infinitely dense? No one knows why or how it expands.
     
  20. Dec 10, 2011 #19
    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    I'm going to find out.. I'll let you know tomorrow. (JOKE!!!!)
     
  21. Dec 10, 2011 #20

    marcus

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    Re: Why is there space? Why isn't the universe just one big ball of infinitely matter

    These seem to be basic questions that people ought to be asking. And I think a few people currently are.
    I hope and expect there will be some progress over the next couple of decades. Maybe not complete answers (almost certainly not complete answers!) but some advances.

    One way to describe the puzzle is that it is about geometry.
    Why are the distances and angles we see the way they are?
    Why do the angles of a triangle add up to approximately 180 degrees and how does the presence of matter change this slightly?

    Matter seems to affect geometry. Why does this happen---what is the underlying mechanism? Have to go, back later.
     
    Last edited: Dec 10, 2011
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