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Full-Text Articles in Physics
Black Holes With Magnetic Charge And Quantized Mass, A. Yu. Ignatiev, G. C. Joshi, Kameshwar C. Wali
Black Holes With Magnetic Charge And Quantized Mass, A. Yu. Ignatiev, G. C. Joshi, Kameshwar C. Wali
Physics - All Scholarship
We examine the issue of magnetic charge quantization in the presence of black holes. It is pointed out that quantization of magnetic charge can lead to the mass quantization for magnetically charged black holes. We also discuss some implications for the experimental searches of magnetically charged black holes.
Monte Carlo Renormalization Of 2d Simplicial Quantum Gravity Coupled To Gaussian Matter, Simon Catterall, Eric B. Gregory, G. Thorleifsson
Monte Carlo Renormalization Of 2d Simplicial Quantum Gravity Coupled To Gaussian Matter, Simon Catterall, Eric B. Gregory, G. Thorleifsson
Physics - All Scholarship
We extend a recently proposed real-space renormalization group scheme for dynamical triangulations to situations where the lattice is coupled to continuous scalar fields. Using Monte Carlo simulations in combination with a linear, stochastic blocking scheme for the scalar fields we are able to determine the leading eigenvalues of the stability matrix with good accuracy both for c = 1 and c = 10 theories.
New Analytical Results On Anisotropic Membranes, Mark Bowick, Alex Travesset
New Analytical Results On Anisotropic Membranes, Mark Bowick, Alex Travesset
Physics - All Scholarship
We report on recent progress in understanding the tubular phase of self-avoiding anisotropic membranes. After an introduction to the problem, we sketch the renormalization group arguments and symmetry considerations that lead us to the most plausible fixed point structure of the model. We then employ an epsilon-expansion about the upper critical dimension to extrapolate to the physical interesting 3-dimensional case. The results are $\nu=0.62$ for the Flory exponent and $\zeta=0.80$ for the roughness exponent. Finally we comment on the importance that numerical tests may have to test these predictions.
Dynamics Of The Conformal Mode And Simplicial Gravity, Simon Catterall, Emil Mottola, T. Bhattacharya
Dynamics Of The Conformal Mode And Simplicial Gravity, Simon Catterall, Emil Mottola, T. Bhattacharya
Physics - All Scholarship
We review the derivation of the Liouville action in 2DQG via the trace anomaly and emphasize how a similar approach can be used to derive an effective action describing the long wavelength dynamics of the conformal factor in 4D. In 2D we describe how to make an explicit connection between dynamical triangulations and this continuum theory, and present results which confirm the equivalance of the two approaches. By reconstructing a lattice conformal mode from DT simulations it should be possible to test this equivalence in 4D also.
Anisotropic Membranes, Simon Catterall, Mark Bowick, Simeon Warner, Gudmar Thorleifsson, Marco Falcioni
Anisotropic Membranes, Simon Catterall, Mark Bowick, Simeon Warner, Gudmar Thorleifsson, Marco Falcioni
Physics - All Scholarship
We describe the statistical behavior of anisotropic crystalline membranes. In particular we give the phase diagram and critical exponents for phantom membranes and discuss the generalization to self-avoiding membranes.
Putative Light Scalar Nonet, Joseph Schechter, Deirdre Black, Amir H. Fariborz, Francesco Sannino
Putative Light Scalar Nonet, Joseph Schechter, Deirdre Black, Amir H. Fariborz, Francesco Sannino
Physics - All Scholarship
We investigate the "family" relationship of a possible scalar nonet composed of the a_0(980), the f_0(980) and the \sigma and \kappa type states found in recent treatments of \pi\pi and \pi K scattering. We work in the effective Lagrangian framework, starting from terms which yield "ideal mixing" according to Okubo's original formulation. It is noted that there is another solution corresponding to dual ideal mixing which agrees with Jaffe's picture of scalars as qq\bar q \bar q states rather than as q\bar q states. At the Lagrangian level there is no difference in the formulation of the two cases (other …
The Tubular Phase Of Self-Avoiding Anisotropic Crystalline Membranes, Mark Bowick, Alex Travesset
The Tubular Phase Of Self-Avoiding Anisotropic Crystalline Membranes, Mark Bowick, Alex Travesset
Physics - All Scholarship
We analyze the tubular phase of self-avoiding anisotropic crystalline membranes. A careful analysis using renormalization group arguments together with symmetry requirements motivates the simplest form of the large-distance free energy describing fluctuations of tubular configurations. The non-self-avoiding limit of the model is shown to be exactly solvable. For the full self-avoiding model we compute the critical exponents using an epsilon-expansion about the upper critical embedding dimension for general internal dimension D and embedding dimension d. We then exhibit various methods for reliably extrapolating to the physical point (D=2,d=3). Our most accurate estimates are nu=0.62 for the Flory exponent and zeta=0.80 …
Disorder-Induced Topological Defects In A D=2 Elastic Medium At Zero Temperature, Alan Middleton
Disorder-Induced Topological Defects In A D=2 Elastic Medium At Zero Temperature, Alan Middleton
Physics - All Scholarship
The density and correlations of topological defects are investigated numerically in a model of a d=2 elastic medium subject to a periodic quenched random potential. The computed density of defects decreases approximately exponentially with the defect core energy. Comparing the defect-free ground state with the ground state with defects, it is found that the difference is described by string-like excitations, bounded by defect pairs, which have a fractal dimension of 1.250(3). At zero temperature, the disorder-induced defects screen the interaction of introduced vortex pairs.
H2 Formation On Interstellar Grains In Different Physical Regimes, Gianfranco Vidali, Ofer Biham, Itay Furman, N. Katz, Valerio Pirronello
H2 Formation On Interstellar Grains In Different Physical Regimes, Gianfranco Vidali, Ofer Biham, Itay Furman, N. Katz, Valerio Pirronello
Physics - All Scholarship
An analysis of the kinetics of H2 formation on interstellar dust grains is presented using rate equations. It is shown that semi-empirical expressions that appeared in the literature represent two different physical regimes. In particular, it is shown that the expression given by Hollenbach, Werner and Salpeter [ApJ, 163, 165 (1971)] applies when high flux, or high mobility, of H atoms on the surface of a grain, makes it very unlikely that H atoms evaporate before they meet each other and recombine. The expression of Pirronello et al.\ [ApJ, 483, L131 (1997)] -- deduced on the basis of accurate measurements …
Pion-Pion Scattering In Two Dimensions, Joseph Schechter, D. Delphenich, S. Vaidya
Pion-Pion Scattering In Two Dimensions, Joseph Schechter, D. Delphenich, S. Vaidya
Physics - All Scholarship
Massive two-flavor QED_2 is known to have many similarities to the two-flavor QCD_4. Here we compare the \pi-\pi scattering amplitudes (actually an analog process in QED_2) of the two theories. The QED_2 amplitude is computed from the bosonized version of the model while the QCD_4 amplitude is computed from an effective low energy chiral Lagrangian. A number of interesting features are noted. For example, the contribution of the two-dimensional Wess-Zumino-Witten (WZW) term in QED_2 is structurally identical to the vector meson exchange contribution in QCD_4. Also it is shown that the QED_2 amplitude computed at tree level is a reasonable …
Evidence For A Scalar Kappa(900) Resonance In Pi-K Scattering, Joseph Schechter, Deirdre Black, Amir H. Fariborz, Francesco Sannino
Evidence For A Scalar Kappa(900) Resonance In Pi-K Scattering, Joseph Schechter, Deirdre Black, Amir H. Fariborz, Francesco Sannino
Physics - All Scholarship
Motivated by the 1/N_c\ expansion, we study a simple model in which the pi-K scattering amplitude is the sum of a current-algebra contact term and resonance pole exchanges. This phenomenological model is crossing symmetric and, when a putative light strange scalar meson, kappa, is included, satisfies the unitarity bounds to well above 1 GeV. The model also features chiral dynamics, vector meson dominance and appropriate interference between the established scalar K*(1430) resonance and its predicted background. We briefly discuss the physical significance of the results and directions for further work.
The Nature Of The Continuum Limit In The 2d Rp^2 Gauge Model, Simon Catterall, M. Hasenbusch, R. R. Horgan, R. Renken
The Nature Of The Continuum Limit In The 2d Rp^2 Gauge Model, Simon Catterall, M. Hasenbusch, R. R. Horgan, R. Renken
Physics - All Scholarship
The RP(2) gauge model is studied in 2D. We use Monte-Carlo renormalization techniques for blocking the mean spin-spin interaction, , and the mean gauge field plaquette. The presence of the O(3) renormalized trajectory is verified and is consistent with the known three-loop beta-function. The first-order `vorticity' transition observed by Solomon et al. is confirmed, and the location of the terminating critical point is established. New scaling flows in (,) are observed associated with a large exponent kappa in the range 4~5. The scaling flows give rise to a strong cross-over effect between regions of high and low vorticity …