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The big bang theory and why i think its wrong

  1. Mar 28, 2010 #1
    The Big Bang Theory:
    The Big Bang Theory is one of many theory's on how the universe was created. From what i have learned of it, the universe was thought to have been created by to atoms (or particles) colliding together and causing a massive explosion which created the universe we know today.

    But what i don't understand is how the two atoms (or particles) would've collided without a force acting upon them.

    One of Isaac Newtons laws states, "An object at rest remains at rest unless acted on by an outside force".

    can any please explain how the atoms (or particles) collided then?
  2. jcsd
  3. Mar 28, 2010 #2


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    This is not true. No wonder you were confused.

    Where did you read this? Regardless, a bit of reading from any trustworthy cosmology book should clear up your confusion.
  4. Mar 28, 2010 #3
    This is not true, either. What the theory describes is how the universe evolved from its earliest moments to the state which it is in today. The cause of the Big Bang, in as far as that juxtaposition of concepts even makes sense, is not even really part of the purview of physics.

    The (biological) Theory of Evolution is an almost exact analogy. It describes how life evolved from its beginnings to the variety we observe today. How those beginnings came about is a question that belongs to an entirely different discipline.
    Last edited: Mar 28, 2010
  5. Mar 28, 2010 #4


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    Good point.
  6. Mar 29, 2010 #5


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    Not to mention that the big bang theory is not one of many theories; it is essentially the only such theory (in the sense of the scientific word "theory").
  7. Mar 29, 2010 #6


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    Scientists are fond of BB theory because it is consistent with a vast body of observational evidence. Little, if any, of this evidence is inconsistent with BB theory. Liking it is optional.
  8. Mar 29, 2010 #7
    In addition to what other people have said, the forces we know today (electromagnetic, gravity, weak, strong) did not exist in the first few moments of the universe. They were combined as one unified force and it was only later that they broke apart: gravity first, then strong and electroweak, then electroweak split into electromagnetism and the weak nuclear force. Also, just as we can't know the exact origins or cause of matter-energy we can't know the origin or cause of that first unified force.

    What some people have deduced is that, since things seem to unify as you trace back to the big bang (forces, matter and energy, other things), that all those unifications might have once been unified. In other words, that somehow forces, time, energy, matter, the empty space between everything, etc. was unified into one, truly zero-dimensional, point. Because there's no way of testing this or any way of collecting evidence, however, as other people have said, this conjecture isn't science, it's closer to philosophy, or science fiction (fiction based in science, in the same sense that fiction based on historical events is historical fiction). Which, to me, is a perfectly acceptable thing, just make sure you know it's not science.
  9. Mar 29, 2010 #8
    Also the big bang wasn't an "explosion" instead it was an expansion. Why it expanded we aren't sure. The fact of the matter is the only other theory to challenge the the big bang was called "The Steady State".

    The name "big bang" was actually coined by the steady state followers to discredit the theory.

    The first short short period of the big bang, was said to contain all of the hydrogen in a small area, this created helium due to the nuclear effect. There is a book "First Three Minutes" https://www.amazon.com/First-Three-Minutes-Modern-Universe/dp/0465024378 <-- amazon link, which discusses the first moments of the theory.
    Last edited by a moderator: Apr 24, 2017
  10. Mar 29, 2010 #9
    I suppose it depends on how short a time period you're talking about, but initially the universe was far too hot for atoms, let alone molecules, to form (they'd simply break apart again). In fact, for the first few micro-seconds or so it was too hot for even the larger subatomic particles (protons and neutrons) to form. After a while, though, things calmed down enough for atoms to form, and, eventually, molecules. The first atoms were probably mostly hydrogen, but a few of them would be others like helium. Some of the hydrogen fused pretty quickly into helium, and, I would guess, helium would occasionally fuse to form other things. Around this time the universe also became transparent (would have basically been a hot white soup before), though I forget which happened first (atoms or transparency).
  11. Mar 29, 2010 #10
    Transparency is the result of recombination, meaning the formation of neutral atoms from nuclei and free electrons. This is basically a chemical process and occurs at much lower energies (and thus at much later times) than the processes that form the nuclei.
  12. Mar 29, 2010 #11


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    atw (according to Wiki):
    Nucleosynthesis (creation of atomic nuclei) occurs between 3 and 20 minutes After BB,
    First Light (transparency) occurs around 377,000 years ABB.

    It is the bonding of electrons to the nuclei, and the resultant neutrally-charged atoms, that causes the universe to turn transparent.

    [EDIT: beat me to it]
  13. Apr 1, 2010 #12
    How can one say that the universe began anyway. You'd be defining it in terms of itself. Wouldn't you need another universe with a stopwatch looking at the the other universe seeing it begin? (And it saying see, It took 45 seconds to do so and so.) How can everything get compressed into a singularity. Wouldn't that break the laws of Quantum Mechanics by being able to define the position and angular momentum of something at the same time?
  14. Apr 1, 2010 #13
    There another thing that confuses me. If the universe is expanding from the BB, won't that effect the force of gravity? Since gravity is the distortion of space. What would the math be on that? Same amount of objects but ever increasing space. objects / space as space -> infinity. Wouldn't the curve of space caused by gravity have to fill up ever increasing volume, especially at it's fringe?
    Last edited: Apr 1, 2010
  15. Apr 1, 2010 #14


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    The physical laws of our universe were brought into existence with its birth. There were no QM laws before or even during the BB.
  16. Apr 1, 2010 #15


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    Objects* are moving apart; their gravity wells move apart with them. The space in between gets flatter. There's no conflict.

    *galaxy clusters. Nothing smaller than galaxy clusters is pulled apart by the expansion of the universe. Gravity of galxies and anythnig smaller easily overwhelms the expansion.
  17. Apr 1, 2010 #16
    So the universe can make up its own rules. Why should it then follow any rules at all?
    I know that it does because otherwise I wouldn't be able to type this over the internet. Since electricity follows all the rules and all the rules could change in an instant. What are the rules that govern the rules? What rules define those rules, and so on Ad infinitum? Wouldn't we get to a point where what we are describing is pointless? Looking from one universe into the next universe where one doesn't care for the other. Are we there right now?
  18. Apr 1, 2010 #17


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    The physical laws of the universe (such as the strength of the four fundamental forces) were fixed in the first few fractions of a second after its birth, in what's called symmetry-breaking. Roll the universe back to the BB and let it run again, and it will assuredly break a different way, leading to completely and utterly different physical laws. There might not even be atoms.

    But since it fell the way it did. This universe follows those rules and always will for its life.
  19. Apr 1, 2010 #18
    "..I forget which happened first..." :rofl: that's just too funny...like, 'well, it was sooo long ago'
  20. Apr 1, 2010 #19
    I wouldn't describe things as following rules, because rules sound like things someone made up. These "rules" you refer to are intrinsic physical and geometrical properties. The rules more accurately are what reasons we assign to these properties.
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