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152 - T. Banks 2015
We construct Holographic Space-time models that reproduce the dynamics of $1 + 1$ dimensional string theory. The necessity for a dilaton field in the $1 + 1$ effective Lagrangian for classical geometry, the appearance of fermions, and even the form o f the universal potential in the canonical $1$ matrix model, follow from general HST considerations. We note that t Hoofts ansatz for the leading contribution to the black hole S-matrix, accounts for the entire S-matrix in these models in the limit that the string scale coincides with the Planck scale, up to transformations between near horizon and asymptotic coordinates. These $1 + 1$ dimensional models are describable as decoupling limits of the near horizon geometry of higher dimensional extremal black holes or black branes, and this suggests that deformations of the simplest model are equally physical. After proposing a notion of relevant deformations, we describe deformations, which contain excitations corresponding to linear dilaton black holes, some of which can be considered as UV completions of the CGHS model. We study the question of whether the AMPS paradox can be formulated in those models. It cannot, because the classical in-fall time to the singularity of linear dilaton black holes, is independent of the black hole mass. This result is reproduced by our HST models. We argue that it is related to the absence of quasi-normal modes of these black hole solutions, which is itself related to the fact that the horizon has zero area. This is compatible with the resolution of the AMPS paradox proposed in previous work with Fischler, according to which the compatibility conditions of HST identify the long non-singular sojourn of observers behind the horizon, with the dynamics of equilibration on the horizon as seen by a detector which has not yet fallen through the horizon.
I summarize Density Functional Theory (DFT) in a language familiar to quantum field theorists, and introduce several apparently novel ideas for constructing {it systematic} approximations for the density functional. I also note that, at least within the large $K$ approximation ($K$ is the number of electron spin components), it is easier to compute the quantum effective action of the Coulomb photon field, which is related to the density functional by algebraic manipulations in momentum space.
122 - Tom Banks , 2012
We summarize recent work in which we attempt to make a consistent model of LHC physics, from the Pyramid Scheme. The models share much with the NMSSM, in particular, enhanced tree level contributions to the Higgs mass and a preference for small tan { beta}. There are 3 different singlet fields, and a new strongly coupled gauge theory, so the constraints of perturbative unification are quite different. We outline our general approach to the model, which contains a Kahler potential for three of the low energy fields, which is hard to calculate. Detailed calculations, based on approximations to the Kahler potential, will be presented in a future publication.
73 - T. Banks 2010
I briefly review the theory of Holographic Space-time and its relation to the cosmological constant problem, and the breaking of supersymmetry (SUSY). When combined with some simple phenomenological requirements, these ideas lead to a fairly unique m odel for Tera-scale physics, which implies direct gauge mediation of SUSY breaking and a model for dark matter as a hidden sector baryon, with nonzero magnetic dipole moment.
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