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Monopole Mass Musings ?

  1. Mar 24, 2015 #1
    Please forgive the thread title.... it just kinda slipped out that way.

    I am reading and enjoying Alan Guth's _The Inflationary Universe_. Dr. Guth is not only in command of a very lucid style of exposition, but he has a very subtle and penetrating sense of humor.

    Anyway..... He relates a conversation with Henry Tye. Essentially, they agreed, GUT implied the existence of magnetic monopoles. They noted that these were likely 10^16 GeV particles; it would take that much energy to create one. Guth estimates that using SLAC as a model, that sort of energy would require (using 1974 technology) a linear accelerator with a length of about 70 light years. It was also noted that this particle would be really heavy with a mass of about 10^17 GeV or about 10^17 times as massive as a proton.

    Now on to my attempt at a scratchpad visualization.

    Taking the mass of a Proton as 1.6726^-27 Kg, (multiple internet sites of reasonable provenance cite this figure), some simple math would place this hypothesized particle to have a mass of approximately 1.67^-10Kg.

    I get that this is huge as a particle mass, but I am really a loss for a sense of scale here. I can write out the numbers. It does not appear macroscopic. Nevertheless, what, for example, weighs about 1.67^-10Kg? Just trying to wrap my head around this unusual, intermediate scale.

  2. jcsd
  3. Mar 24, 2015 #2


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  4. Mar 24, 2015 #3
    Thanks...cool.... looks like it is sorta nominally macroscopic after all.

    I didn't think to look for orders of magnitude..... I just kicked around the number and didn't get all that far. ;)


    P.S. That really is one heck of a massive proposed particle.

    P.P.S. Scratching around, it looks like the Higgs Boson, a very massive particle, has a mass of approximately 126 protons.
    Last edited: Mar 24, 2015
  5. Mar 25, 2015 #4


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    The Higgs boson is 14 orders of magnitude lighter than the suggest GUT scale. And it is lighter than the top quark.
  6. Mar 25, 2015 #5

    Doug Huffman

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    The Planck Mass is often compared to a flea's egg or a dust mote (Susskind).

    Susskind attributes some of our difficulties to the anthropocentric scale that we impress on the universe.
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