319 research outputs found
What is quantum field theory and why have some physicists abandoned it?
No full textThe present-day crisis in quantum field theory is described.Comment: Email correspondence to [email protected] ; 4 pages, LaTe
EIKONAL* R. Jackiw, D. Kabat
No full textElectromagnetic fields of a massless charged particle are described by a gauge potential that is almost everywhere a pure gauge. Solution of quantum mechanical wave equations in the presence of such fields is therefore immediate and leads to a new derivation of the quantum electrodynamical eikonal approximation. The electromagnetic action in the eikonal limit is localized on a contour in a two-dimensional Minkowski subspace of four-dimensional spacetime. The exact S-matrix of this reduced theory coincides with the eikonal approximation. Some years ago, 't Hooft derived the eikonal approximation for the two-particle scattering amplitude arising from their gravitational interaction. 1 However, he did not sum eikonal graphs (graviton exchange graphs with particle propagators approximated by neglecting virtual graviton momenta compared to particle momenta). Rather he solved quantum mechanical equations for one particle moving in the gravitational field of the other, which is taken mass..
Analogia magnetostática do estado de energia zero de Jackiw-Rebbi
No full textA theoretical analogy is established between Poisson’s equation and Dirac’s equation; specifically, when studying the behavior of the magnetostatic field, due to the susceptibility in non- homogeneous, non-isotropic, one-dimensional media with high magnetic permeability. As a result, a connection with the Jackiw-Rebbi model for the zero energy state was found.Se establece una analogía teórica entre la ecuación de Poisson y la ecuación de Dirac; específicamente, al estudiar el comportamiento del campo magnetostático, debido a la susceptibilidad en medios no homogéneos, no isotrópicos, unidimensionales, con alta permeabilidad magnética. Como resultado, se obtuvo una relación con el modelo de Jackiw-Rebbi para el estado de energía cero.É estabelecida uma analogia teórica entre a equação de Poisson e a equação Dirac; especificamente, ao estudar o comportamento do campo magnetostático, devido à suscetibilidade em meios não homogêneos, não isotrópicos, unidimensionais, com alta permeabilidade magnética. Como resultado, foi obtida uma relação com o modelo de Jackiw-Rebbi para o estado de energia zero
Analogia magnetostática do estado de energia zero de Jackiw-Rebbi
No full textA theoretical analogy is established between Poisson’s equation and Dirac’s equation; specifically, when studying the behavior of the magnetostatic field, due to the susceptibility in non- homogeneous, non-isotropic, one-dimensional media with high magnetic permeability. As a result, a connection with the Jackiw-Rebbi model for the zero energy state was found.Se establece una analogía teórica entre la ecuación de Poisson y la ecuación de Dirac; específicamente, al estudiar el comportamiento del campo magnetostático, debido a la susceptibilidad en medios no homogéneos, no isotrópicos, unidimensionales, con alta permeabilidad magnética. Como resultado, se obtuvo una relación con el modelo de Jackiw-Rebbi para el estado de energía cero.É estabelecida uma analogia teórica entre a equação de Poisson e a equação Dirac; especificamente, ao estudar o comportamento do campo magnetostático, devido à suscetibilidade em meios não homogêneos, não isotrópicos, unidimensionais, com alta permeabilidade magnética. Como resultado, foi obtida uma relação com o modelo de Jackiw-Rebbi para o estado de energia zero
Tutorial on scale and conformal symmetries in diverse dimensions
No full textWe review the relation between scale and conformal symmetries in various models and dimensions. We present a dimensional reduction from relativistic to non-relativistic conformal dynamics.United States. Dept. of Energy (Cooperative Research Agreement DE-FG02-05ER41360
Supergroup structure of Jackiw-Teitelboim supergravity
No full textWe develop the gauge theory formulation of N = 1 Jackiw-Teitelboim supergravity in terms of the underlying OSp(1 vertical bar 2, R) supergroup, focusing on boundary dynamics and the exact structure of gravitational amplitudes. We prove that the BF description reduces to a super-Schwarzian quantum mechanics on the holographic boundary, where boundary-anchored Wilson lines map to bilocal operators in the super-Schwarzian theory. A classification of defects in terms of monodromies of OSp(1 vertical bar 2, R) is carried out and interpreted in terms of character insertions in the bulk. From a mathematical perspective, we construct the principal series representations of OSp(1 vertical bar 2, R) and show that whereas the corresponding Plancherel measure does not match the density of states of N = 1 JT supergravity, a restriction to the positive subsemigroup OSp(+)(1 vertical bar 2, R) yields the correct density of states, mirroring the analogous results for bosonic JT gravity. We illustrate these results with several gravitational applications, in particular computing the late-time complexity growth in JT supergravity
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