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Power counting of loop diagrams in general relativity
Cyclic graph the general theory of relativity energy expansion quantum effects physical power calculation
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2014/12/23
A class of loop diagrams in general relativity appears to have a behavior which would upset the utility of the energy expansion for quantum effects. We show through the study of specific diagrams that...
Is B→Xsγ equal to b→sγ? Spectator contributions to rare inclusive B decays
With perturbation quark-gluon hadron attenuation photon spectral lines the photon energy
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2014/12/23
In B→Xsγ, there are perturbative QCD corrections at order αs not only to the single quark line process b→sγ but also coming from a set of diagrams where the weak interaction vertex involves a gluon wh...
Improving the Convergence of SU(3) Baryon Chiral Perturbation Theory
Baryon chiral perturbation theory the chiral expansion momentum space physics
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2014/12/23
Baryon chiral perturbation theory as conventionally applied using dimensional regularization has a well-known problem with the convergence of the SU(3) chiral expansion. One can reformulate the theory...
The Electromagnetic Mass Differences of Pions and Kaons
Meson kaon electromagnetic depend on the model input high energy kaon
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2014/12/23
We use the Cottingham method to calculate the pion and kaon electromagnetic mass differences with as few model dependent inputs as possible. The constraints of chiral symmetry at low energy, QCD at hi...
The Quantum Theory of General Relativity at Low Energies
Quantum field theory low energy quantum the interaction energy general relativity low energy
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2014/12/23
In quantum field theory there is now a well developed technique, effective field theory, which allows one to obtain low energy quantum predictions in “non-renormalizable” theories, using only the degr...
I discuss the progress in the use of analytic techniques for low energy QCD, in particular as applied to kaon physics. These methods are becoming increasingly powerful and we have gained a good deal o...
Final state interactions in the decay of heavy quarks
Secondary scattering B meson duality
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2014/12/23
I discuss some recent results on the systematic behavior of final state rescattering which makes use of the limit of a heavy B meson. The results suggest that soft final state interactions do not disa...
Systematics of soft final-state interactions in B decays
Traditional expectations state interaction inelastic scattering
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2014/12/23
By using very general and well established features of soft strong interactions we show, contrary to conventional expectations, that (i) soft final-state interactions (FSI) do not disappear for large ...
Effective Hamiltonian in the Problem of a "Central Spin" Coupled to a Spin Environment
Spin quantum interactive microcosmic spin micro rotation magnetic particles low-energy properties model
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2014/12/23
We consider here the problem of a "giant spin", with spin quantum number S≫1, interacting with a set of microscopic spins. Interactions between the microscopic spins are ignored. This model desc...
We show that recent calculations of ΔI=3/2 effects in nonleptonic hyperon decay induced by md-mu≠0 are subject to significant model dependence. [S0556-2821(97)04819-4]
Bose-Einstein condensation in a harmonic potential
Bose - Einstein condensation thermodynamics space condensation the particles
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2014/12/23
We examine several features of Bose-Einstein condensation (BEC) in an external harmonic potential well. In the thermodynamic limit, there is a phase transition to a spatial Bose-Einstein condensed sta...
Chiral Perturbation Theory and Nucleon Polarizabilities
Compton scattering nuclear structure
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2014/12/22
Compton scattering offers in principle an intriguing new window on nucleon structure. Existing experiments and future programs are discussed and the state of theoretical understanding of such measurem...
Virtual Compton scattering off the nucleon in chiral perturbation theory
The Compton scattering amplitude chiral perturbation theory gw amplitude
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2014/12/22
We investigate the spin-independent part of the virtual Compton scattering (VCS) amplitude off the nucleon within the framework of chiral perturbation theory. We perform a consistent calculation to th...
Generalized polarizabilities and the chiral structure of the nucleon
Chiral perturbation theory the generalized polarizability function virtual Compton scattering measurements electron scattering
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2014/12/22
We present results of the first chiral perturbation theory calculation for the generalized polarizabilities of the nucleon and discuss the response functions in virtual Compton scattering to be measur...
Systematic 1/M expansion for spin 3/2 particles in baryon chiral perturbation theory
The theory of relativity pion - nucleon - delta system spin 3/2 resonance nuclear soft power the quality of meson
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2014/12/22
Starting from a relativistic formulation of the pion-nucleon-delta system, the most general structure of 1/M corrections for a heavy baryon chiral lagrangian including spin 3/2 resonances is given. Th...