Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 11 of 11
Full-Text Articles in Physical Sciences and Mathematics
Qcd Condensates For The Light Quark V-A Correlator, Vincenzo Cirigliano, Eugene Golowich, Kim Maltman
Qcd Condensates For The Light Quark V-A Correlator, Vincenzo Cirigliano, Eugene Golowich, Kim Maltman
Physics Department Faculty Publication Series
No abstract provided.
Spatial And Temporal Gradients In The Cosmological Constant, Jf Donoghue
Spatial And Temporal Gradients In The Cosmological Constant, Jf Donoghue
Physics Department Faculty Publication Series
It is possible that there may be differences in the fundamental physical parameters from one side of the observed universe to the other. I show that the cosmological constant is likely to be the most sensitive of the physical parameters to possible spatial (or temporal) variation, because a small variation in any of the other parameters produces a huge variation of the cosmological constant. It therefore provides a very powerful indirect evidence against spatial gradients or temporal variation in the other fundamental physical parameters, at least 40 orders of magnitude more powerful than direct experimental constraints. Moreover, a gradient may …
Quantum Gravitational Corrections To The Nonrelativistic Scattering Potential Of Two Masses, Nej Bjerrum-Bohr, Jf Donoghue, Br Holstein
Quantum Gravitational Corrections To The Nonrelativistic Scattering Potential Of Two Masses, Nej Bjerrum-Bohr, Jf Donoghue, Br Holstein
Physics Department Faculty Publication Series
We treat general relativity as an effective field theory, obtaining the full nonanalytic component of the scattering matrix potential to one-loop order. The lowest order vertex rules for the resulting effective field theory are presented and the one-loop diagrams which yield the leading nonrelativistic post-Newtonian and quantum corrections to the gravitational scattering amplitude to second order in G are calculated in detail. The Fourier transformed amplitudes yield a nonrelativistic potential and our result is discussed in relation to previous calculations. The definition of a potential is discussed as well, and we show that the ambiguity of the potential under coordinate …
Comment On “Phase Diagram Of A Disordered Boson Hubbard Model In Two Dimensions”, N Prokof’Ev, B Svistunov
Comment On “Phase Diagram Of A Disordered Boson Hubbard Model In Two Dimensions”, N Prokof’Ev, B Svistunov
Physics Department Faculty Publication Series
In a recent Letter [1] (see also [2]) the authors presented numerical evidence supporting an idea of a direct transition between the superfluid (SF) and Mott insulating (MI) phases in the disordered Bosonic system, and even studied non-trivial properties of the multicritical line where SF, MI and the Bose Glass (BG) phases meet. The results were obtained from Monte Carlo simulations of the (2+1)-dimensional classical loop-current model [3] with the lattice action S = 1 2K ÞE ~ J=0 XrƒÑ ~ J2(r, ƒÑ) . 2(ƒÊ + v(r)) ~ JƒÑ (r, ƒÑ) . (1) where r, ƒÑ are spatial and imaginary …
From Wrapped M-Branes To Calabi-Yau Black Holes And Strings, David Kastor
From Wrapped M-Branes To Calabi-Yau Black Holes And Strings, David Kastor
Physics Department Faculty Publication Series
We study a class of D = 11 BPS spacetimes that describe M-branes wrapping supersymmetric 2 and 4-cycles of Calabi-Yau 3-folds. We analyze the geometrical significance of the supersymmetry constraints and gauge field equations of motion for these spacetimes. We show that the dimensional reduction to D = 5 yields known BPS black hole and black string solutions of D = 5, N = 2 supergravity. The usual ansatz for the dimensional reduction is valid only in the linearized regime of slowly varying moduli and small gauge field strengths. Our identification of the massless D = 5 modes with D …
New Evidence For Zero-Temperature Relaxation In A Spin-Polarized Fermi Liquid, H Akimoto, D Candela, Js Xia, Wj Mullin, Ed Adams, Ns Sullivan
New Evidence For Zero-Temperature Relaxation In A Spin-Polarized Fermi Liquid, H Akimoto, D Candela, Js Xia, Wj Mullin, Ed Adams, Ns Sullivan
Physics Department Faculty Publication Series
Spin-echo experiments are reported for 3He-4He solutions under extremely high B/T conditions, B=14.75 T and T≥1.73 mK. The 3He concentration x3 was adjusted close to the value xc≈3.8% at which the spin-rotation parameter μM0 vanishes. In this way the transverse and longitudinal spin-diffusion coefficients D⊥,D∥ were measured while keeping |μM0|<1. It is found that the temperature dependence of D⊥ deviates strongly from 1/T2, with anisotropy temperature Ta=4.26-0.44+0.18 mK. This value is close to the theoretical prediction for dilute solutions and suggests that spin current relaxation remains finite as the temperature tends to zero.
Quantum Corrections To The Schwarzschild And Kerr Metrics, Nej Bjerrum-Bohr, Jf Donoghue, Br Holstein
Quantum Corrections To The Schwarzschild And Kerr Metrics, Nej Bjerrum-Bohr, Jf Donoghue, Br Holstein
Physics Department Faculty Publication Series
No abstract provided.
K ->Pi Pi Electroweak Penguins In The Chiral Limit, V Cirigliano, Jf Donoghue, Eugene Golowich, K Maltman
K ->Pi Pi Electroweak Penguins In The Chiral Limit, V Cirigliano, Jf Donoghue, Eugene Golowich, K Maltman
Physics Department Faculty Publication Series
We report on dispersive and finite energy sum rule analyses of the electroweak penguin matrix elements left angle bracket(ππ)2|Q7,8|K0right-pointing angle bracket in the chiral limit. We accomplish the correct perturbative matching (scale and scheme dependence) at NLO in αs, and we describe two different strategies for numerical evaluation.
Incoherent Dynamics Of Vibrating Single-Molecule Transistors, K Mccarthy,, Nikolai Prokof'ev, M Tuominen
Incoherent Dynamics Of Vibrating Single-Molecule Transistors, K Mccarthy,, Nikolai Prokof'ev, M Tuominen
Physics Department Faculty Publication Series
We study the tunneling conductance of nanoscale quantum “shuttles” in connection with a recent experiment [H. Park et al., Nature 407, 57 (2000)] in which a vibrating C60 molecule was apparently functioning as the island of a single electron transistor (SET). While our calculation starts from the same model of previous work [D. Boese and H. Schoeller, Europhys. Lett. 54, 668 (2001)] we obtain quantitatively different dynamics. Calculated I-V curves exhibit most features present in experimental data with a physically reasonable parameter set, and point to a strong dependence of the oscillator’s potential on the electrostatics of the island region. …
Bose-Einstein Condensation, Fluctuations, And Recurrence Relations In Statistical Mechanics, Wj Mullin, Jp Fernandez
Bose-Einstein Condensation, Fluctuations, And Recurrence Relations In Statistical Mechanics, Wj Mullin, Jp Fernandez
Physics Department Faculty Publication Series
We calculate certain features of Bose–Einstein condensation in the ideal gas by using recurrence relations for the partition function. The grand canonical ensemble gives inaccurate results for certain properties of the condensate that are accurately provided by the canonical ensemble. Calculations in the latter can be made tractable for finite systems by means of the recurrence relations. The ideal one-dimensional harmonic Bose gas provides a particularly simple and pedagogically useful model for which detailed results are easily derived. An analysis of the Bose system via permutation cycles yields insight into the physical meaning of the recurrence relations.
Quantum Statistics: Is There An Effective Fermion Repulsion Or Boson Attraction?, Wj Mullin, G Blaylock
Quantum Statistics: Is There An Effective Fermion Repulsion Or Boson Attraction?, Wj Mullin, G Blaylock
Physics Department Faculty Publication Series
Physicists often claim that there is an effective repulsion between fermions, implied by the Pauli principle, and a corresponding effective attraction between bosons. We examine the origins and validity of such exchange force ideas and the areas where they are highly misleading. We propose that explanations of quantum statistics should avoid the idea of an effective force completely, and replace it with more appropriate physical insights, some of which are suggested here.