English
Related papers

Related papers: Potent Value and Potent Operator with Pre- and Pos…

200 papers

A general approach describing quantum decision procedures is developed. The approach can be applied to quantum information processing, quantum computing, creation of artificial quantum intelligence, as well as to analyzing decision…

Quantum Physics · Physics 2015-05-14 V. I. Yukalov , D. Sornette

We present a general formalism for charecterizing 2-time quantum states, describing pre- and post-selected quantum systems. The most general 2-time state is characterized by a `density vector' that is independent of measurements performed…

Quantum Physics · Physics 2014-01-30 Ralph Silva , Yelena Guryanova , Nicolas Brunner , Noah Linden , Anthony J. Short , Sandu Popescu

Measurement is a fundamental notion in the usual approximate quantum mechanics of measured subsystems. Probabilities are predicted for the outcomes of measurements. State vectors evolve unitarily in between measurements and by reduction of…

General Relativity and Quantum Cosmology · Physics 2014-01-14 James B. Hartle

Physical interpretations of the time-symmetric formulation of quantum mechanics, due to Aharonov, Bergmann, and Lebowitz are discussed in terms of weak values. The most direct, yet somewhat naive, interpretation uses the time-symmetric…

Quantum Physics · Physics 2022-01-25 Mordecai Waegell , Eliahu Cohen , Avshalom Elitzur , Jeff Tollaksen , Yakir Aharonov

Quantum computing is powerful because unitary operators describing the time-evolution of a quantum system have exponential size in terms of the number of qubits present in the system. We develop a new "Singular value transformation"…

Quantum Physics · Physics 2020-02-21 András Gilyén , Yuan Su , Guang Hao Low , Nathan Wiebe

A quantum mechanical observer might be describable as having a reference system that is a superposition of classical inertial reference frames. The present paper suggests a possible weighting function in such superpositions, determined by…

General Physics · Physics 2009-05-27 M. Dance

Understanding the core content of quantum mechanics requires us to disentangle the hidden logical relationships between the postulates of this theory. Here we show that the mathematical structure of quantum measurements, the formula for…

Quantum Physics · Physics 2019-04-02 Lluís Masanes , Thomas D. Galley , Markus P. Müller

The quantum-mechanical state vector is not directly observable even though it is the fundamental variable that appears in Schrodinger's equation. In conventional time-dependent perturbation theory, the state vector must be calculated before…

Quantum Physics · Physics 2009-11-07 J. D. Franson , Michelle M. Donegan

The diverse range of resources which underlie the utility of quantum states in practical tasks motivates the development of universally applicable methods to measure and compare resources of different types. However, many of such approaches…

Quantum Physics · Physics 2021-03-19 Bartosz Regula , Ludovico Lami , Giovanni Ferrari , Ryuji Takagi

Strong-field quantum-state control is investigated, taking advantage of the full---amplitude and phase---characterization of the interaction between matter and intense ultrashort pulses via transient-absorption spectroscopy. A sequence of…

Atomic Physics · Physics 2017-04-26 Stefano M. Cavaletto , Zoltán Harman , Thomas Pfeifer , Christoph H. Keitel

It is shown how, given a "probability data table" for a quantum or classical system, the representation of states and measurement outcomes as vectors in a real vector space follows in a natural way. Some properties of the resulting sets of…

Quantum Physics · Physics 2007-05-23 Piero G. L. Mana

The variance of an observable in a pre-selected quantum system, which is always real and non-negative, appears as an increase in the probe wave packet width in indirect measurements. Extending this framework to pre- and post-selected…

Quantum Physics · Physics 2021-07-28 Kazuhisa Ogawa , Natsuki Abe , Hirokazu Kobayashi , Akihisa Tomita

In the operator formalism of quantum mechanics, the density operator describes the complete statistics of a quantum state in terms of d^2 independent elements, where d is the number of possible outcomes for a precise measurement of an…

Quantum Physics · Physics 2014-09-30 Holger F. Hofmann

This work will incorporate a few related tools for addressing the conceptual difficulties arising from sewing together classical and quantum mechanics: deterministic operators, weak measurements and post-selection. Weak Measurement, based…

Quantum Physics · Physics 2016-12-21 Eliahu Cohen , Yakir Aharonov

It is argued that the partition of a quantum system into subsystems is dictated by the set of operationally accessible interactions and measurements. The emergence of a multi-partite tensor product structure of the state-space and the…

Quantum Physics · Physics 2011-04-29 Paolo Zanardi , Daniel Lidar , Seth Lloyd

The production and manipulation of quantum correlation protocols will play a central role where the quantum nature of the correlation can be used as a resource to yield properties unachievable within a classical framework is a very active…

Quantum Physics · Physics 2022-03-09 Simon J. D Phoenix , Faisal Shah Khan , Berihu Teklu

Quantum money represents an innovative approach to currency by encoding economic value within the quantum states of physical systems, utilizing the principles of quantum mechanics to enhance security, integrity, and transferability. This…

Quantum Physics · Physics 2025-07-15 Artur Czerwinski

Students in quantum mechanics class are taught that the wave function contains all knowable information about an isolated system. Later in the course, this view seems to be contradicted by the mysterious density matrix, which introduces a…

General Physics · Physics 2021-04-16 Mark G. Kuzyk

An operational description of quantum phenomena concerns developing models that describe experimentally observed behaviour. $\textit{Higher-order quantum operations}\unicode{x2014}$quantum operations that transform quantum…

Quantum Physics · Physics 2025-03-14 Philip Taranto , Simon Milz , Mio Murao , Marco Túlio Quintino , Kavan Modi

Quantum sensors are among the most promising quantum technologies, allowing to attain the ultimate precision limit for parameter estimation. In order to achieve this, it is required to fully control and optimize what constitutes the…

Quantum Physics · Physics 2020-05-19 Ilaria Gianani , Marco G. Genoni , Marco Barbieri