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A time inhomogeneous generalized Mehler semigroup on a real separable Hilbert space ${\mathds{H}}$ is defined through $$ p_{s,t}f(x)=\int_{\mathds{H}} f(U(t,s)x+y)\,\mu_{t,s}(dy), \quad t\geq s, \ x\in{\mathds{H}} $$ for every bounded…

Probability · Mathematics 2012-09-12 Shun-Xiang Ouyang , Michael Röckner

Physics explains the laws of motion that govern the time evolution of observable properties and the dynamical response of systems to various interactions. However, quantum theory separates the observable part of physics from the…

Quantum Physics · Physics 2019-01-23 Holger F. Hofmann

The space-fractional and the time-fractional Poisson processes are two well-known models of fractional evolution. They can be constructed as standard Poisson processes with the time variable replaced by a stable subordinator and its…

Probability · Mathematics 2016-08-09 Luisa Beghin , Costantino Ricciuti

The concept of time emerges as an ordering structure in a classical statistical ensemble. Probability distributions $p_\tau(t)$ at a given time $t$ obtain by integrating out the past and future. We discuss all-time probability distributions…

High Energy Physics - Theory · Physics 2015-05-18 C. Wetterich

The sensitivity of the evolution of quantum uncertainties to the choice of the initial conditions is shown via a complex nonlinear Riccati equation leading to a reformulation of quantum dynamics. This sensitivity is demonstrated for systems…

Quantum Physics · Physics 2015-05-27 Hans Cruz , Dieter Schuch , Octavio Castaños , Oscar Rosas-Ortiz

We present a quantum algorithm for simulating the time evolution generated by any bounded, time-dependent operator $-A$ with non-positive logarithmic norm, thereby serving as a natural generalization of the Hamiltonian simulation problem.…

Quantum Physics · Physics 2025-09-15 Guang Hao Low , Rolando D. Somma

Relativistically, time $t$ is an observable just like position $r$. In quantum theory, $t$ is a parameter, in contrast to the observable $r$. This discrepancy suggests that there exists a more elaborate formalization of time, which…

Quantum Physics · Physics 2019-01-08 Per Östborn

A general quantum constraint of the form $C= - \partial_T^2 \otimes B - I\otimes H$ (realized in particular in Loop Quantum Cosmology models) is studied. Group Averaging is applied to define the Hilbert space of solutions and the relational…

General Relativity and Quantum Cosmology · Physics 2010-04-14 Wojciech Kaminski , Jerzy Lewandowski , Tomasz Pawlowski

The unitary operators U(t), describing the quantum time evolution of systems with a time-dependent Hamiltonian, can be constructed in an explicit manner using the method of time-dependent invariants. We clarify the role of Lie-algebraic…

Mathematical Physics · Physics 2008-05-30 Maciej Kuna , Jan Naudts

We combine the "evolving constants" approach to the construction of observables in canonical quantum gravity with the Page--Wootters formulation of quantum mechanics with a relational time for generally covariant systems. This overcomes the…

General Relativity and Quantum Cosmology · Physics 2009-11-06 Rodolfo Gambini , Rafael Porto , Sebastian Torterolo , Jorge Pullin

Known as no fast-forwarding theorem in quantum computing, the simulation time for the Hamiltonian evolution needs to be $O(\|H\| t)$ in the worst case, which essentially states that one can not go across the multiple scales as the…

Quantum Physics · Physics 2025-01-30 Yonah Borns-Weil , Di Fang

We analize the relational quantum evolution of generally covariant systems in terms of Rovelli's evolving constants of motion and the generalized Heisenberg picture. In order to have a well defined evolution, and a consistent quantum…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Rodolfo Gambini , Rafael A. Porto

We consider in a Hilbert space a self-adjoint operator H and a family Phi=(Phi_1,...,Phi_d) of mutually commuting self-adjoint operators. Under some regularity properties of H with respect to Phi, we propose two new formulae for a time…

Mathematical Physics · Physics 2009-08-21 Serge Richard , Rafael Tiedra de Aldecoa

Quantum uncertainty relations have deep-rooted significance on the formalism of quantum mechanics. Heisenberg's uncertainty relations attracted a renewed interest for its applications in quantum information science. Robertson derived a…

Quantum Physics · Physics 2023-02-16 Md. Manirul Ali

An observable on a quantum structure is any $\sigma$-homomorphism of quantum structures from the Borel $\sigma$-algebra into the quantum structure. We show that our partial information on an observable known only for all intervals of the…

Mathematical Physics · Physics 2012-05-01 Anatolij Dvurečenskij , Mária Kuková

Quantum mechanical time operator is introduced following the parametric formulation of classical mechanics in the extended phase space. Quantum constraint on the extended quantum system is defined in analogy to the constraint of the…

Quantum Physics · Physics 2011-02-15 Nikola Buri\' c , Slobodan Prvanovi\' c

A relation expressing the covariant transformation properties of a relativistic position operator is derived. This relation differs from the one existing in the literature expressing manifest covariance by some factor ordering. The relation…

General Relativity and Quantum Cosmology · Physics 2007-05-23 J. Mourad

Decaying states can be represented by Gamow vectors with an exponential, asymmetric time evolution. This asymmetric evolution is a manifestation of irreversibility on the microphysical level. The Rigged Hilbert Space provides a mathematical…

Nuclear Theory · Physics 2007-05-23 Arno R. Bohm , Raymond Scurek , Sujeewa Wikramasekara

Hamiltonian mechanics describes the evolution of a system through its Hamiltonian. The Hamiltonian typically also represents the energy observable, a Noether-conserved quantity associated with the time-invariance of the law of evolution. In…

Quantum Physics · Physics 2024-03-29 Libo Jiang , Daniel R. Terno , Oscar Dahlsten

A method based off of operator consideration for solving the time evolution of a wave function is developed. The method is applied to free space, constant force and harmonic oscillator potentials where general solutions are derived for the…

Quantum Physics · Physics 2012-08-14 K. P. Michnicki