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Why Are We Made of Matter?

StartsWithABang (3485481) writes "The Universe began with equal amounts of matter and antimatter after the Big Bang, and yet when we look out at today's Universe, we find that, even on the largest scales, it's made of at least 99.999%+ matter and not antimatter. The problem of how we went from a matter-antimatter-symmetric Universe to the matter-dominated one we have today is known as baryogenesis, and is one of the greatest unsolved problems in physics. Where are we on the quest to understand it as of April, 2014? A wonderful and comprehensive recap is here."

16 of 393 comments (clear)

  1. Ah, antimatter by AdamColley · · Score: 5, Funny

    God hid it.

    God is made of it.

    Okay, that's the god excuses out of the way... now on with the physics!

    1. Re:Ah, antimatter by Shakrai · · Score: 4, Insightful

      Ah, the obligatory /. cheap shot at religion, always good for a cheap +5 funny. You failed to complete the cliche though, there should have been a slam aimed at the GOP in there somewhere.

      --
      I want peace on earth and goodwill toward man.
      We are the United States Government! We don't do that sort of thing.
    2. Re:Ah, antimatter by Bengie · · Score: 4, Funny

      Finally, news that matters.

    3. Re:Ah, antimatter by PopeRatzo · · Score: 5, Insightful

      there should have been a slam aimed at the GOP in there somewhere.

      Oh, if you insist: The GOP is using peoples' religion to encourage them to think of themselves as butthurt victims, creating divisiveness and the notion that in a nation where there's a church on every other streetcorner, religious people are somehow the oppressed, and they're doing it, not because they care about those religious beliefs or religious people, but in order to create a political climate where it's easier to redistribute wealth upwards.

      Oops, I'm sorry. You specifically requested a cheap shot and that wasn't one. I'll do better next time.

      --
      You are welcome on my lawn.
    4. Re:Ah, antimatter by Immerman · · Score: 4, Informative

      Nope. Antimatter is still basically "normal" matter, just with the opposite charge. We've created a fair bit of it in the lab, especially anti-hydrogen and various anti-subatomic particles The mass appears to be the same, and it interacts with light and other EM fields just as normal matter does. The only real difference is that when you bring a matter particle together with its antimatter twin they mutually annihilate.

      Dark matter on the other hand would have to interact only via gravity, no electromagnetism to promote "clumping" into atoms or larger structures, nor any absorption or emission of light or we would be able to see evidence of its existence in the spectrum and brightness of distant stars.

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
  2. Actually... by TubeSteak · · Score: 4, Funny

    By mass, I'm currently ~70% water, ~29.5% matter, and 0.5% cookie dough

    Disclaimer: Do not eat raw cookie dough made with unpasteurized eggs.

    --
    [Fuck Beta]
    o0t!
  3. Re:Something From Nothing. by bunratty · · Score: 5, Informative

    Actually, the big bang theory simply says that the universe started in a hot, dense state and expanded into a cold, sparse state. It doesn't even try to explain how the universe came to be in that hot, dense state. It is similar to how evolution does not even try to explain how life started, just how species evolve once they exist.

    --
    What a fool believes, he sees, no wise man has the power to reason away.
  4. What if there is no reason? by kruach+aum · · Score: 5, Interesting

    In spite of my better judgement I'm about to attempt an analogy, so bear with me here. The lowest number of moves to unscramble a maximally scrambled rubik's cube (a 3x3x3 one) is 20. That is, for every configuration of a rubik's cube, there is a sequence of 20 moves or less that will unscramble it. However, there is no algorithm to generate those solutions. They are unstructured; they're simply lists of moves. The algorithms used by human (and computer) rubik's cube solvers are far from move-optimal, but benefit from being executable by non-omniscient beings. They pick out some pattern that is applicable to the rubik's cube, and then direct you in manipulating it according to that pattern until it's solved.

    The way science understands the world is by comparing new data to what we already know. For example, we know penicillin kills bacteria; if we discover a new disease, and then discover that it is caused by bacteria, we can safely draw the conclusion that we'll probably be able to treat it with penicillin. We've used science to discover a pattern in the world ('penicillin kills bacteria'), then use deduction to determine where it is and isn't applicable, and form new categories based on what happens when we encounter new data (like bacteria not killed by penicillin being classified as anti-biotic resistant). Science is basically a collection of patterns like this, and because they're patterns (structures, structured rules, whatever you want to call them) we can understand them.

    Now, what I wonder about is this. What if the fact that we live in a matter universe now (rather than an anti-matter one) is like the set of move-optimal solutions to a rubik's cube? They both describe a certain state of affairs, but they also both completely lack (could lack) any kind of structure. And because they lack this structure, there is nothing for us to latch onto, nothing for us to understand, no pattern to detect. It is simply the case, and there is no further reason. There is no reason why there is no structure in the move-optimal solutions to a rubik's cube. There might not be a reason why there is a massive matter/anti-matter imbalance either.

    This is something I've been trying to work out for a while, so please excuse me if my explanation is unclear. I just think it would be a really interesting possibility, something which isn't often discussed, maybe because it simply gets overlooked.

  5. Matter-Antimatter Explosions by seyfarth · · Score: 4, Interesting

    I wonder if it is possible that the Universe has some regions of matter and some of antimatter. In between there would be mixed regions and the resulting explosions could tend to keep the different regions separate. Initially asymmetry in the distribution would leave some small regions of each type. The m-am explosions could force separation and a certain portion of the matter regions would merge with other matter regions and the same for antimatter. This seems like a fairly obvious thought, so I assume that it has been considered and ruled out. Why or why not?

    --
    Ray Seyfarth, ray.seyfarth@gmail.com, http://rayseyfarth.blogspot.com
  6. Re:Probably due to spin by PolygamousRanchKid+ · · Score: 4, Interesting

    tell me something in terms an idiot would understand

    Richard Feynman answered that question with something like:

    "I can't explain it in terms that you would understand, because I can't understand it, in terms that you would understand."

    --
    Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
  7. Why Are We Made of Matter? by Zontar+The+Mindless · · Score: 4, Funny

    Because we travel the way we do through time.

    Antimatter travels through it in the other direction.

    And we when we and the antimatter get all the way from one end of Time to the other--BOOM! It's the end.

    .gninnigeb eht s'tI !MOOB--rehto eht ot emiT fo dne eno morf yaw eht lla teg rettamitna eht dna ew nehw ew dnA

    --
    Il n'y a pas de Planet B.
  8. Re:easy by Smallpond · · Score: 4, Informative

    Why do people think these simple questions are hard???

    I agree. It's almost as if they don't read past the headline.

  9. Re:civilizations' bottleneck by stoploss · · Score: 4, Insightful

    As soon as physicists solve the problem of antimatter the antimatter bomb will be created.

    It will be the size of a coin and could literally destroy literally a quoter of a planet. This is how civilizations end in the Universe.

    You vastly overstate the yield of an antimatter weapon.

    antimatter weapon yield calculator

  10. Re:So what? by Eunuchswear · · Score: 5, Funny

    There are 3 kinds of universes -

    1. mostly matter
    2. 50/50
    3. mostly antimatter.

    In type 1 universes everyone is asking "why is everything made of matter".
    type 2 universes are empty.
    type 3 universes electricty flows the right way.

    --
    Watch this Heartland Institute video
  11. Re:So what? by Anonymous Coward · · Score: 5, Funny

    type 3 universes electricty flows the right way.

    Unfortunately the name of the direction is wrong.

  12. If anti-matter won ... by TrollstonButterbeans · · Score: 4, Insightful

    We wouldn't be calling it anti-matter, we would just call it "matter" and would be still asking the same question.

    So there are really only 2 scenarios.

    --
    Priest: "Universe from nothing, no laws of physics, sped up time"+ huge discrepancies. Creationism? No. Big Bang Theory