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Standard model says 17 particals, M theory says 18?

  1. Dec 30, 2015 #1
    Hi. I've only just started reading on M-theory. I'm otherwise a lay person so I'm going to have some basic questions. Here's my first.

    Standard Model has 17 elementary particles right? But doesn't M-theory say there's 18? Or 36 if you include the symetrical ones. So am I missing one partical? Or are the theories talking about something different.

    I can see that my book mentions the graviton, which isn't in the standard model, so maybe that's the difference?

  2. jcsd
  3. Dec 30, 2015 #2


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    How many particles you get depends on exactly what you decide to count as one particle. For example, I assume you counted Z and W as different particles. Why then did you not count 8 gluons? This is something subjective and therefore not a very relevant part of how science is done.
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