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Question about the number of particles in the standard model.

  1. Mar 13, 2013 #1
    Hi, I was just wondering why there are a finite number of fundamental particles in the universe. Why is it that when cern collide particles, the same particles are formed every time. Its like putting a hammer to a concrete block and every time you do so, the same chips with the same shape and size are broken off. Surely, if the protons were smashed at different energys and directions, new "chips" would be formed. Afterall, a particle can have, theoretically, any mass,spin,charge,etc possible. Why is it the same properties emerging every time? When the universe was created, why were MILLIONS of diffferent paricles not formed? I dont get it.
    Any help would be appreciated as I cant seem to find any on the web.
  2. jcsd
  3. Mar 13, 2013 #2


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    Uh ... why SHOULD there be a different set of particles than what exists? Physics is about explaining what exists, not worrying about things that don't exist.
  4. Mar 13, 2013 #3
    That`s exactly my point. Why are things the way they are ?
  5. Mar 13, 2013 #4


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    "Why" is a question that is almost impossible to answer. Physics tries to explain how things are, but not why, when it comes to fundamentals.
  6. Mar 13, 2013 #5
    that p*sses me off .. that we`ll never know, i mean
  7. Mar 13, 2013 #6


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    There are enough REAL things to worry about. If you plan on going through life making up things to worry about, you are going to have a very frustrating life.
  8. Mar 13, 2013 #7
    You presume there is a "thing" or "reason" to know at all. This may be yet another example of projecting our intuitive world view onto the universe at large.
  9. Mar 13, 2013 #8
    The subject is more philosophical than scientific, but that shouldn't scare us away from it, because we can actually say something productive about it based on our current knowledge of fundamental physics. We currently describe fundamental physics with quantum field theory. This may not be the ultimately correct framework, but it works well for what we've seen so far.

    Now, quantum field theory does not work like the everyday world. In normal life, if you, say, shatter a piece of glass, each piece is uniquely shaped and no object like it has ever existed before. In quantum field theory, by contrast, there are certain types of particles and all particles of a given type are utterly identical. That is, the math of quantum field theory turns out to provide an elegant reason for why all electrons are apparently exactly identical, and we never find electrons with, say, slightly different mass or charge.

    Now, when you write down a quantum field theory, you can have whatever types of particles you want, but you have to explicitly add a term to your theory for every new type of particle that exists. If you wanted to describe millions of different particle types it would be exhausting to write down the millions of terms in the theory. So presumably God got tired after writing out the terms for a dozen or so particles, and called it a day. Less flippantly, in light of the above it does sort of seem "natural" for there to be a relatively small number of particle types, with each particle of a given type being identical to any other.
  10. Mar 13, 2013 #9
    I'd look at this simpler.
    The higher you go the more complicated things get.But by complicated I don't mean harder to understand rather more possible outcomes.
    bricks are mostly the same yet the houses that are built of them differ alot.
    The hair on ones head are similar yet the hairstyles and the length of each individual hair can be different.But the basic structure of them is the same.

    It's like there is a digit 1 you can write every number in terms of how many ones added to ones it contains.Just like the subatomic particles , they are the same in the micro world but their number and relationship in a certain piece of matter determines the unique properties of that certain material.
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