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Quantum Field Theory and Mereological Nihilism/Atomism

  1. Nov 18, 2009 #1
    Research in relativistic quantum mechanics proves, through a series of no-go theorems, that localized three (or four) dimensional particles cannot be the basic elements of reality. It is claimed that a field ontology can explain the appearance of three dimensional particles, but this new idea hasn't (and in principle can't) be proven. It is sufficient for my question to realize, however, that we have proof that three dimensional particles are not the basic elements of reality. See "No place for particles in relativistic quantum theories?" at http://www.journals.uchicago.edu/doi/abs/10.1086/338939 or http://arxiv.org/abs/quant-ph/0103041 and other research at http://www.princeton.edu/~hhalvors/papers/.

    The result that three dimensional particles can't be the basic elements of reality is important to mereology in that philosophers have typically assumed physics does claim that particles are basic. This can be seen, for example, in the beginning of Ted Sider's '07 paper responding to mereological priority monism (http://tedsider.org/papers/against_monism.pdf):
    Typically mereology has been approached by asking what happens when we take an object and chop it up into smaller and smaller bits. Are objects made of infinitely divisible "gunk" or discrete indivisible atoms? It is (naively?) assumed that if you take something of homogeneous density and cut it in half, both halves will maintain the same density. This is supposed to hold true ad infinitum for gunk or until we can't divide anymore for atoms. But what are the implications when we know the basic elements of reality don't have such properties as localized mass or density? If fields or strings or whatever are all that exist, and they don't have such a property as mass, how is is that when we add them up we get an object that we would like to say has mass as one of its essential properties?

    Is mass more akin to macroscopic properties like temperature than anything fundamental? If so, what business do anything but fundamental properties have in ontology or mereology?

    Is this all just disproof of a particle ontology and further support for Schaffer's top-down priority monism as presented in "Monism: The Priority of the Whole" (http://rsss.anu.edu.au/~schaffer/papers/Monism.pdf [Broken])? Or are fields or strings perfectly acceptable mereological simples, even given the mismatch between field properties and the properties of macroscopic objects?

    The realization that our three dimensional objects are not simply constructed from smaller three dimensional parts must have wide ranging implications for mereology. What are they?

    More reference:
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Nov 18, 2009 #2
    Naive realsim is only to be found in naive human perception. Calculations in QCD show that more than 90% of mass of matter is due to virtual particles. Some expect that number to reach 100% when the higgs is found.
    Most approaches to QG are aiming for background-independence and they treat space and matter as an(emergent) special case of a yet unknown phenomenon. Blackholes are a good example where naive realism hits the wall head-on. Anyway, as you are aware the 3-dimensionality of matter becomes apparent because of superpositions of states of zero-dimensional 'objects' + Pauli's exclusion principle. There is no 3D physical matter without the exchange of virtual particles which form the basis of 3D shapes of physical objects.

    Physics has been borrowing topics from philosophy for the last 100 years, as Lee Smolin likes to put it.

    Did anyone think that reality was perceivable and comprehensible without a mind? We are in a strong causal loop with what we experience.
    Anyway, it's so amazing that the classical world we perceive appears so real.
    Last edited: Nov 18, 2009
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