Spin-½

About: Spin-½ is a research topic. Over the lifetime, 40423 publications have been published within this topic receiving 796639 citations.

Black holes in three dimensional higher spin gravity: a review

Abstract: We review recent progress in the construction of black holes in three dimensional higher spin gravity theories. Starting from spin-3 gravity and working our way toward the theory of an infinite tower of higher spins coupled to matter, we show how to harness higher spin gauge invariance to consistently generalize familiar notions of black holes. We review the construction of black holes with conserved higher spin charges and the computation of their partition functions to leading asymptotic order. In view of the anti-de Sitter/conformal field theory (CFT) correspondence as applied to certain vector-like conformal field theories with extended conformal symmetry, we successfully compare to CFT calculations in a generalized Cardy regime. A brief recollection of pertinent aspects of ordinary gravity is also given.This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Higher spin theories and holography’.

Hidden-Variable Example Based upon Data Rejection

Abstract: A deterministic local hidden-variable model is presented which describes the simultaneous measurement of the spins of two spin-\textonehalf{} particles which emerged from the decay of a spin-zero particle. In this model the measurement of the spin of a particle has one of three possible outcomes: spin parallel to the apparatus axis, spin antiparallel to the apparatus axis, or the particle goes undetected. It is shown that agreement with the predictions of quantum theory is obtained provided the experimenter rejects the "anomalous" data in which only one particle is detected. A reasonably model-independent lower bound to the fraction of undetected particles is also computed: It is found that in 14% of the decays or more, one or both of the particles will go undetected.

Higher spin gauge theory and holography: the three-point functions

Abstract: In this paper we calculate the tree level three-point functions of Vasiliev's higher spin gauge theory in AdS4 and find agreement with the correlators of the free field theory of N massless scalars in three dimensions in the O(N) singlet sector. This provides substantial evidence that Vasiliev theory is dual to the free field theory, thus verifying a conjecture of Klebanov and Polyakov. We also find agreement with the critical O(N) vector model, when the bulk scalar field is subject to the alternative boundary condition such that its dual operator has classical dimension 2.

A Theory of Electrons and Protons

Abstract: The relativity quantum theory of an electron moving in a given electro­magnetic field, although successful in predicting the spin properties of the electron, yet involves one serious difficulty which shows that some fundamental alteration is necessary before we can regard it as an accurate description of nature. This difficulty is connected with the fact that the wave equation, which is of the form [W/ c + e / c A + ρ1 (σ, p + e / c A) + ρ3 mc ] Ψ = 0, (1) has, in addition to the wanted solutions for which the kinetic energy of the electron is positive, an equal number of unwanted solutions with negative kinetic energy for the electron, which appear to have no physical meaning. Thus if we take the case of a steady electromagnetic field, equation (1) will admit of periodic solutions of the form Ψ = u e - i E t / h , (2) where u is independent of t , representing stationary states, E being the total energy of the state, including the relativity term mc 2. There will then exist solutions (2) with negative values for E as well as those with positive values ; in fact, if we take a matrix representation of the operators ρ1σ1, ρ1σ2, ρ1σ3, ρ3 with the matrix elements all real, then the conjugate complex of any solution of (1) will be a solution of the wave equation obtained from (1) by reversal of the sign of the potentials A, and either the original wave function or its con­jugate complex must refer to a negative E.