6,011 research outputs found

    Phase 0 Workshop at the 20th EORTC-NCI-AACR Symposium, Geneva

    Get PDF

    Renormalization group irreversible functions in more than two dimensions

    Get PDF
    There are two general irreversibility theorems for the renormalization group in more than two dimensions: the first one is of entropic nature, while the second one, by Forte and Latorre, relies on the properties of the stress-tensor trace, and has been recently questioned by Osborn and Shore. We start by establishing under what assumptions this second theorem can still be valid. Then it is compared with the entropic theorem and shown to be essentially equivalent. However, since the irreversible function of the (corrected) Forte-Latorre theorem is non universal (whereas the relative entropy of the other theorem is universal), it needs the additional step of renormalization. On the other hand, the irreversibility theorem is only guaranteed to be unambiguous if the integral of the stress-tensor trace correlator is finite, which happens for free theories only in dimension smaller than four.Comment: 4 pages; minor changes to improve readability; to appear in Phys. Rev.

    The Heat Kernel on AdSAdS

    Get PDF
    We explicitly evaluate the heat kernel for the Laplacian of arbitrary spin tensor fields on the thermal quotient of (Euclidean) AdSNAdS_N for N≥3N\geq 3 using the group theoretic techniques employed for AdS3AdS_3 in arXiv:0911.5085. Our approach is general and can be used, in principle, for other quotients as well as other symmetric spaces.Comment: Added references, added appendix on heat kernel in even dimensio

    The Heat Kernel on AdS_3 and its Applications

    Full text link
    We derive the heat kernel for arbitrary tensor fields on S^3 and (Euclidean) AdS_3 using a group theoretic approach. We use these results to also obtain the heat kernel on certain quotients of these spaces. In particular, we give a simple, explicit expression for the one loop determinant for a field of arbitrary spin s in thermal AdS_3. We apply this to the calculation of the one loop partition function of N=1 supergravity on AdS_3. We find that the answer factorizes into left- and right-moving super Virasoro characters built on the SL(2, C) invariant vacuum, as argued by Maloney and Witten on general grounds.Comment: 46 pages, LaTeX, v2: Reference adde

    Forms on Vector Bundles Over Hyperbolic Manifolds and the Conformal Anomaly

    Full text link
    We study gauge theories based on abelian p−p-forms on real compact hyperbolic manifolds. An explicit formula for the conformal anomaly corresponding to skew--symmetric tensor fields is obtained, by using zeta--function regularization and the trace tensor kernel formula. Explicit exact and numerical values of the anomaly for p−p-forms of order up to p=4p=4 in spaces of dimension up to n=10n=10 are then calculated.Comment: 13 pages, 2 table

    Graviton 1-loop partition function for 3-dimensional massive gravity

    Full text link
    The graviton 1-loop partition function in Euclidean topologically massive gravity (TMG) is calculated using heat kernel techniques. The partition function does not factorize holomorphically, and at the chiral point it has the structure expected from a logarithmic conformal field theory. This gives strong evidence for the proposal that the dual conformal field theory to TMG at the chiral point is indeed logarithmic. We also generalize our results to new massive gravity.Comment: 19 pages, v2: major revision, considerably stronger conclusions, added comparison with LCFT partition function, confirmation of LCFT conjecture, added autho

    An approach for the calculation of one-loop effective actions, vacuum energies, and spectral counting functions

    Full text link
    In this paper, we provide an approach for the calculation of one-loop effective actions, vacuum energies, and spectral counting functions and discuss the application of this approach in some physical problems. Concretely, we construct the equations for these three quantities; this allows us to achieve them by directly solving equations. In order to construct the equations, we introduce shifted local one-loop effective actions, shifted local vacuum energies, and local spectral counting functions. We solve the equations of one-loop effective actions, vacuum energies, and spectral counting functions for free massive scalar fields in Rn\mathbb{R}^{n}, scalar fields in three-dimensional hyperbolic space H3H_{3} (the Euclidean Anti-de Sitter space AdS3AdS_{3}), in H3/ZH_{3}/Z (the geometry of the Euclidean BTZ black hole), and in S1S^{1}, and the Higgs model in a (1+1)(1+1)-dimensional finite interval. Moreover, in the above cases, we also calculate the spectra from the counting functions. Besides exact solutions, we give a general discussion on approximate solutions and construct the general series expansion for one-loop effective actions, vacuum energies, and spectral counting functions. In doing this, we encounter divergences. In order to remove the divergences, renormalization procedures are used. In this approach, these three physical quantities are regarded as spectral functions in the spectral problem.Comment: 37 pages, no figure. This is an enlarged and improved version of the paper published in JHE

    Generalised massive gravity one-loop partition function and AdS/(L)CFT

    Full text link
    The graviton 1-loop partition function is calculated for Euclidean generalised massive gravity (GMG) using AdS heat kernel techniques. We find that the results fit perfectly into the AdS/(L)CFT picture. Conformal Chern-Simons gravity, a singular limit of GMG, leads to an additional contribution in the 1-loop determinant from the conformal ghost. We show that this contribution has a nice interpretation on the conformal field theory side in terms of a semi-classical null vector at level two descending from a primary with conformal weights (3/2,-1/2).Comment: 25 p., 2 jpg figs, v2: added 6 lines of clarifying text after Eq. (2.38
    • …
    corecore