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It is shown that in two-state quantum theory, a generic quantum state can be described by a non-computable real number. In terms of this, the criterion for measurement outcome is simply and deterministically defined. This demonstration is…

Quantum Physics · Physics 2007-05-23 T. N. Palmer

How would the world appear to us if its ontology was that of classical mechanics but every agent faced a restriction on how much they could come to know about the classical state? We show that in most respects, it would appear to us as…

Quantum Physics · Physics 2012-07-12 Stephen D. Bartlett , Terry Rudolph , Robert W. Spekkens

For classical field theories with probabilistic initial conditions the classical field observables are an idealization. Their arbitrarily precise values poorly reflect the characteristic uncertainty in the presence of substantial…

Quantum Physics · Physics 2026-03-06 Christof Wetterich

Quantum theory of the free Maxwell field in Minkowski space is constructed using a representation in which the self dual connection is diagonal. Quantum states are now holomorphic functionals of self dual connections and a decomposition of…

High Energy Physics - Theory · Physics 2010-11-01 Abhay Ashtekar , Carlo Rovelli , Lee Smolin

Three major misconceptions concerning quantized tachyon fields: the energy spectrum unbounded from below, the frame-dependent and unstable vacuum state, and the non-covariant commutation rules, are shown to be a result of misrepresenting…

The different roles and natures of spacetime appearing in a quantum field theory and in classical physics are analyzed implying that a quantum theory of gravitation is not necessarily a quantum theory of curved spacetime. Developing an…

General Relativity and Quantum Cosmology · Physics 2015-06-16 C. Wiesendanger

Quantum field theory (QFT) on non-stationary spacetimes is well understood from the side of the algebra of observables. The state space, however, is largely unexplored, due to the non-existence of distinguished states (vacuum, scattering…

General Relativity and Quantum Cosmology · Physics 2018-09-25 Klaus Fredenhagen , Thomas-Paul Hack , Nicola Pinamonti

A simple mathematical extension of quantum theory is presented. As well as opening the possibility of alternative methods of calculation, the additional formalism implies a new physical interpretation of the standard theory by providing a…

Quantum Physics · Physics 2020-03-17 Roderick Sutherland

We review the mathematically rigorous formulation of the quantum theory of a linear field propagating in a globally hyperbolic spacetime. This formulation is accomplished via the algebraic approach, which, in essence, simultaneously admits…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Robert M. Wald

We develop a reformulation of the functional integral for bosons in terms of bilocal fields. Correlation functions correspond to quantum probabilities instead of probability amplitudes. Discrete and continuous global symmetries can be…

High Energy Physics - Theory · Physics 2010-04-14 S. Floerchinger

We consider a simple quantum system subjected to a classical random force. Under certain conditions it is shown that the noise-averaged Wigner function of the system follows an integro-differential stochastic Liouville equation. In the…

High Energy Physics - Theory · Physics 2008-02-03 Salman Habib

We present a general formalism for studying the effects of dynamical heterogeneity in open quantum systems. We develop this formalism in the state space of density operators, on which ensembles of quantum states can be conveniently…

Quantum Physics · Physics 2019-09-04 Amro Dodin , Adam P. Willard

Before we ask what the quantum gravity theory is, it is a legitimate quest to formulate a robust quantum field theory in curved spacetime (QFTCS). Several conceptual problems, especially unitarity loss (pure states evolving into mixed…

High Energy Physics - Theory · Physics 2024-12-31 K. Sravan Kumar , João Marto

Regularization of quantum field theories (QFT's) can be achieved by quantizing the underlying manifold (spacetime or spatial slice) thereby replacing it by a non-commutative matrix model or a ``fuzzy manifold'' . Such discretization by…

High Energy Physics - Theory · Physics 2007-05-23 Badis Ydri

A general formulation of classical relativistic particle mechanics is presented, with an emphasis on the fact that superluminal velocities and nonlocal interactions are compatible with relativity. Then a manifestly relativistic-covariant…

High Energy Physics - Theory · Physics 2019-11-19 H. Nikolic

It is shown that the operator sum representation for non-Markovian dynamics and the Lindblad master equation in Markovian limit can be derived from a formal solution to quantum Liouville equation for a qubit system in the presence of…

Quantum Physics · Physics 2009-11-07 Doyeol Ahn , Jinhyoung Lee , S. W. Hwang

The problem of measurement in quantum mechanics is that the quantum particle in the course of evolution, as described by the linear Schrodinger equation, exists in all of its possible states, but in measuring, the particle is always…

Quantum Physics · Physics 2013-11-04 Alexey V. Melkikh

The relation between the distribution of work performed on a classical system by an external force switched on an arbitrary timescale, and the corresponding equilibrium free energy difference, is generalized to quantum systems. Using the…

Statistical Mechanics · Physics 2007-05-23 Shaul Mukamel

We consider the quantum mechanics of a particle on a noncommutative plane. The case of a charged particle in a magnetic field (the Landau problem) with a harmonic oscillator potential is solved. There is a critical point, where the density…

High Energy Physics - Theory · Physics 2011-05-05 V. P. Nair , A. P. Polychronakos

We explain that a bulk with arbitrary dimensions can be added to the space over which a quantum field theory is defined. This gives a TQFT such that its correlation functions in a slice are the same as those of the original quantum field…

High Energy Physics - Theory · Physics 2016-09-06 Laurent Baulieu