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Related papers: Comment on Complex Extension of Quantum Mechanics

200 papers

This is an up-to-date survey of the p-mechanical construction (see funct-an/9405002, quant-ph/9610016, math-ph/0007030, quant-ph/0212101, quant-ph/0303142), which is a consistent physical theory suitable for a simultaneous description of…

Quantum Physics · Physics 2014-11-18 Alastair Brodlie , Vladimir V. Kisil

We discuss the notion about physical quantities as having values represented by real numbers, and its limiting to describe nature to be understood in relation to our appreciation that the quantum theory is a better theory of natural…

Quantum Physics · Physics 2021-01-13 Otto C. W. Kong , Wei-Yin Liu

Some of the problems connected with the interpretation of quantum mechanics are enumerated, in particular those related to some well known paradoxes and, above all, to the measurement process. We then show how the so called "Physics…

Quantum Physics · Physics 2026-01-05 Luigi E. Picasso

In study of pseudo(quasi)-hermitian operators, the key role is played by the positive-definite metric operator. It enables physical interpretation of the considered systems. In the article, we study the pseudo-hermitian systems with…

Quantum Physics · Physics 2011-11-17 Vit Jakubsky

This paper considers the relevance of the concepts of observability and computability in physical theory. Observability is related to verifiability which is essential for effective computing and as physical systems are computational systems…

General Physics · Physics 2012-06-28 Subhash Kak

We discuss some general properties of quantum gravity in De Sitter space. It has been argued that the Hilbert space is of finite dimension. This suggests a macroscopic argument that General Relativity cannot be quantized -- unless it is…

High Energy Physics - Theory · Physics 2007-05-23 Edward Witten

We show that, contrarily to the widespread belief, in quantum mechanics repeatable measurements are not necessarily described by orthogonal projectors--the customary paradigm of "observable". Nonorthogonal repeatability, however, occurs…

Quantum Physics · Physics 2007-05-23 F. Buscemi , G. M. D'Ariano , P. Perinotti

We start with a discussion of the use of mathematics to model the real world then justify the role of Hilbert space formalism for such modelling in the general context of quantum logic. Following this, the incompleteness of the…

Quantum Physics · Physics 2024-03-21 Matthew F. Brown

Bender et al. have developed PT-symmetric quantum theory as an extension of quantum theory to non-Hermitian Hamiltonians. We show that when this model has a local PT symmetry acting on composite systems it violates the non-signaling…

Quantum Physics · Physics 2014-04-25 Yi-Chan Lee , Min-Hsiu Hsieh , Steven T. Flammia , Ray-Kuang Lee

PT-symmetric quantum mechanics is an alternative formulation of quantum mechanics in which the mathematical axiom of Hermiticity (transpose and complex conjugate) is replaced by the physically transparent condition of space-time reflection…

Mathematical Physics · Physics 2015-06-12 Huai-Xin Cao , Zhi-Hua Guo , Zheng-Li Chen

We introduce the concept of a "classical observable" as an operator with vanishingly small quantum fluctuations on a set of density matrices. It is shown how to construct them for a time evolved pure state. The study of classical…

Quantum Physics · Physics 2014-04-29 Michiel Wouters

An extension of the scope of quantum theory is proposed in a way inspired by the recent heuristic as well as phenomenological success of the use of non-Hermitian Hamiltonians which are merely required self-adjoint in a Krein space with an…

Mathematical Physics · Physics 2015-10-16 Miloslav Znojil

The direct observability of coordinates x is often lost in PT-symmetric quantum theories. A manifestly non-local Hilbert-space metric $\Theta$ enters the double-integral normalization of wave functions $\psi(x)$ there. In the context of…

High Energy Physics - Theory · Physics 2009-09-02 Miloslav Znojil

Update: A time-independent $n\times n$ PT-symmetric (and symmetric) Hamiltonian is diagonalizable since it has all distinct real eigenvalues and the resulting diagonal matrix is a real symmetric matrix. The diagonalization results an…

Quantum Physics · Physics 2014-05-20 Sungwook Lee , Lawrence R. Mead

We consider the problem of designing a variety of "system guided" basis sets for quantum mechanical anharmonic oscillators. Using ideas based on supersymmetric quantum mechanics, we design canonical transformations of the usual position and…

Quantum Physics · Physics 2017-01-12 Donald J. Kouri , Cameron L. Williams , Nikhil Pandyaq

In this report, we reply to a recent comment by Carl M. Bender, Gregorio Benincasa and Hugh F. Jones on our work 'New ansatz for metric operator calculation in pseudo-Hermitian field theory (Phys. Rev. D. 79, 107702 (2009)). In fact, they…

High Energy Physics - Theory · Physics 2009-12-16 Abouzeid M. Shalaby

We are dealing in this work with such formal and conceptual extensions of nonrelativistic quantum mechanics (QM) which contain QM with its standard formalism and interpretation as a subtheory. QM is here primarily equivalently reformulated…

Mathematical Physics · Physics 2020-07-25 Pavel Bóna

Pseudo-Hermitian operators generalize the concept of Hermiticity. This class of operators includes the quasi-Hermitian operators, which reformulate quantum theory while retaining real-valued measurement outcomes and unitary time evolution.…

Quantum Physics · Physics 2023-06-08 Jacob L. Barnett

We introduce a new way of quantifying the degrees of incompatibility of two ob- servables in a probabilistic physical theory and, based on this, a global measure of the degree of incompatibility inherent in such theories, across all…

Quantum Physics · Physics 2013-08-23 Paul Busch , Teiko Heinosaari , Jussi Schultz , Neil Stevens

Quantum mechanics predicts the joint probability distributions of the outcomes of simultaneous measurements of commuting observables, but the current formulation lacks the operational definition of simultaneous measurements. In order to…

Quantum Physics · Physics 2009-11-06 Masanao Ozawa