Date: Thu, 29 Jul 10 00:05:07 GMT Subject: hep-lat daily 3 new + 3 crosses received by eprepget ------------------------------------------------------------------------------ ------------------------------------------------------------------------------ Send any comments regarding submissions directly to submitter. ------------------------------------------------------------------------------ Archives at http://arxiv.org/ To unsubscribe, e-mail To: hep-lat@arXiv.org, Subject: cancel ------------------------------------------------------------------------------ received by eprepget from Tue 27 Jul 10 20:00:00 GMT to Wed 28 Jul 10 20:00:00 GMT ------------------------------------------------------------------------------ \\ arXiv:1007.4871 Date: Wed, 28 Jul 2010 05:10:04 GMT (157kb) Title: Ordering of Spin-$\frac{1}{2}$ Excitations of the Nucleon in Lattice QCD Authors: M. S. Mahbub, Waseem Kamleh, Derek B. Leinweber, Alan \'O Cais, Anthony G. Williams Categories: hep-lat Comments: 9 pages Report-no: ADP-10-15/T711 \\ We present results for the negative parity low-lying state of the nucleon, $N{\frac{1}{2}}^{-}$ (1535 MeV) ${\rm S}_{11}$, from a variational analysis method. The analysis is performed in quenched QCD with the FLIC fermion action. The principal focus of this paper is to explore the level ordering between the Roper (${\rm{P}}_{11}$) and the negative parity ground (${\rm{S}}_{11}$) states of the nucleon. Evidence of the physical level ordering is observed at light quark masses. A wide variety of smeared-smeared correlation functions are used to construct correlation matrices. A comprehensive correlation matrix analysis is performed to ensure an accurate isolation of the $N{\frac{1}{2}}^{-}$ state. \\ ( http://arxiv.org/abs/1007.4871 , 157kb) ------------------------------------------------------------------------------ \\ arXiv:1007.4885 Date: Wed, 28 Jul 2010 07:41:23 GMT (41kb) Title: The vicinity of the phase transition in the lattice Weinberg - Salam Model Authors: M.A.Zubkov Categories: hep-lat hep-ph Comments: Proceedings of QUARKS-2010 \\ We investigated the lattice Weinberg - Salam model without fermions for the Higgs mass around $300$ GeV. On the phase diagram there exists the vicinity of the phase transition between the physical Higgs phase and the unphysical symmetric phase, where the fluctuations of the scalar field become strong while Nambu monopoles are dense. According to our numerical results (obtained on the lattices of sizes up to $20^3\times 24$) the maximal value of the ultraviolet cutoff in the model cannot exceed the value around $1.4$ TeV. \\ ( http://arxiv.org/abs/1007.4885 , 41kb) ------------------------------------------------------------------------------ \\ arXiv:1007.4897 Date: Wed, 28 Jul 2010 08:39:27 GMT (263kb) Title: Longitudinal and transverse meson correlators in the deconfined phase Authors: G.Aarts, C.R.Allton, S.J.Hands, J.Foley and S.Kim Categories: hep-lat Comments: Talk presented by C.R. Allton at the International Lattice Symposium Villasimius, Italy, June 2010. 7 pages \\ QCD undergoes a deconfining transition at high temperature to a "quark-gluon plasma" phase where hadrons may become unbound. In this work, meson correlation functions at non-zero momentum are studied both in the confined and plasma phases using the Maximum Entropy Method. In particular, both the longitudinal and transverse modes of the vector correlation functions are considered. Only in the case of light quarks in the plasma phase, we find that both longitudinal and transverse spectral functions have a non-zero intercept at zero energy. \\ ( http://arxiv.org/abs/1007.4897 , 263kb) %-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%-%- ------------------------------------------------------------------------------ \\ arXiv:1007.4829 (*cross-listing*) Date: Tue, 27 Jul 2010 21:30:52 GMT (53kb) Title: New Phenomena in NC Field Theory and Emergent Spacetime Geometry Authors: Badis Ydri Categories: hep-th gr-qc hep-lat hep-ph Comments: 16 pages,7 figures, a contribution to the Constantine workshop on Astronomy and Astrophysics, june 2010 \\ We give a brief review of two nonperturbative phenomena typical of noncommutative field theory which are known to lead to the perturbative instability known as the UV-IR mixing. The first phenomena concerns the emergence/evaporation of spacetime geometry in matrix models which describe perturbative noncommutative gauge theory on fuzzy backgrounds. In particular we show that the transition from a geometrical background to a matrix phase makes the description of noncommutative gauge theory in terms of fields via the Weyl map only valid below a critical value g_*. The second phenomena concerns the appearance of a nonuniform ordered phase in noncommutative scalar \phi^4 field theory and the spontaneous symmetry breaking of translational/rotational invariance which happens even in two dimensions. We argue that this phenomena also originates in the underlying matrix degrees of freedom of the noncommutative field theory. Furthermore it is conjectured that in addition to the usual WF fixed point at $\theta=0$ there must exist a novel fixed point at \theta=\infty corresponding to the quartic hermitian matrix model. \\ ( http://arxiv.org/abs/1007.4829 , 53kb) ------------------------------------------------------------------------------ \\ arXiv:1007.4839 (*cross-listing*) Date: Tue, 27 Jul 2010 22:23:32 GMT (567kb) Title: Mixed dark matter from technicolor Authors: Alexander Belyaev, Mads T. Frandsen, Subir Sarkar, Francesco Sannino Categories: hep-ph hep-ex hep-lat Comments: LaTeX, 9 pages, 8 figures \\ We study natural composite cold dark matter candidates which are pseudo Nambu-Goldstone bosons (pNGB) in models of dynamical electroweak symmetry breaking. Some of these can have a significant thermal relic abundance, while others must be mainly asymmetric dark matter. By considering the thermal abundance alone we find a lower bound of MW on the pNGB mass when the (composite) Higgs is heavier than 115 GeV. Being pNGBs, the dark matter candidates are in general light enough to be produced at the LHC. \\ ( http://arxiv.org/abs/1007.4839 , 567kb) ------------------------------------------------------------------------------ \\ arXiv:1007.4854 (*cross-listing*) Date: Tue, 27 Jul 2010 23:49:04 GMT (140kb) Title: Gravity/Spin-model correspondence and holographic superfluids Authors: Umut Gursoy Categories: hep-th cond-mat.supr-con hep-lat Comments: 68 pages + appendices, 4 figures \\ We propose a general correspondence between gravity and spin models, inspired by the well-known IR equivalence between lattice gauge theories and the spin models. This suggests a connection between continuous type Hawking-phase transitions in gravity and the continuous order-disorder transitions in ferromagnets. The black-hole phase corresponds to the ordered and the graviton gas corresponds to the disordered phases respectively. A simple set-up based on Einstein-dilaton gravity indicates that the vicinity of the phase transition is governed by a linear-dilaton CFT. Employing this CFT we calculate scaling of observables near T_c, and obtain mean-field scaling in a semi-classical approximation. In case of the XY model the Goldstone mode is identified with the zero mode of the NS-NS two-form. We show that the second speed of sound vanishes at the transition also with the mean field exponent. \\ ( http://arxiv.org/abs/1007.4854 , 140kb) %%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%%--%% ------------------------------------------------------------------------------ \\ arXiv:1006.0172 replaced with revised version Wed, 28 Jul 2010 17:14:19 GMT (23kb) Title: Chiral Lattice Fermions, Minimal Doubling, and the Axial Anomaly Authors: Brian C. Tiburzi Categories: hep-lat hep-ph nucl-th Comments: 15 pages, 1 figure, symmetries corrected, Symanzik analysis for currents added, marginal operators exposed Report-no: UMD-40762-479, INT-PUB-10-023 \\ ( http://arxiv.org/abs/1006.0172 , 23kb) %%%---%%%---%%%---%%%---%%%---%%%---%%%---%%%---%%%---%%%---%%%---%%%---%%%--- For subscribe options to combined physics archives, e-mail To: physics@arXiv.org, Subject: subscribe ----------------------------------------------------------------------------- For help on viewing and making submissions, see http://arXiv.org/help/ For a list of archive mirror sites, see http://arXiv.org/servers.html ----------------------------------------------------------------------------- Third-party submissions cause excessive problems. Author self-submissions are exceedingly preferred. E-mail submissions have been discontinued in favor of better support for Web submissions. See http://arXiv.org/help/uploads