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Register a new userCosmological interplay between general relativity and particle physics
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Added by
Michael Maziashvili
Publication date
2008
fields
Physics
and research's language is
English
Authors
Michael Maziashvili
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We clearly formulate and study further a conjecture of effective field theory interaction with gravity in the cosmological context. The conjecture stems from the fact that the melding of quantum theory and gravity typically indicates the presence of an inherent UV cutoff. Taking note of the physical origin of this UV cutoff, that the background metric fluctuations does not allow QFT to operate with a better precision than the background space resolution, we conjecture that the converse statement might also be true. That is, an effective field theory could not perceive the background space with a better precision than it is allowed by its intrinsic UV scale. Some of the subtleties and cosmological implications of this conjecture are explored.
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We extend a recent computation of the dependence of the free energy, F, on the noncommutative scale $theta$ to theories with very different UV sensitivity. The temperature dependence of $F$ strongly suggests that a reduced number of degrees of freedom contributes to the free energy in the non-planar sector, $F_{rm np}$, at high temperature. This phenomenon seems generic, independent of the UV sensitivity, and can be traced to modes whose thermal wavelengths become smaller than the noncommutativity scale. The temperature dependence of $F_{rm np}$ can then be calculated at high temperature using classical statistical mechanics, without encountering a UV catastrophe even in large number of dimensions. This result is a telltale sign of the low number of degrees of freedom contributing to $F$ in the non-planar sector at high temperature. Such behavior is in marked contrast to what would happen in a field theory with a random set of higher derivative interactions.
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