Results 61 to 70 of about 103,519 (218)

$J$-self-adjoint operators with $\mathcal{C}$-symmetries: extension theory approach

, 2008
A well known tool in conventional (von Neumann) quantum mechanics is the self-adjoint extension technique for symmetric operators. It is used, e.g., for the construction of Dirac-Hermitian Hamiltonians with point-interaction potentials.
, Albeverio S, Albeverio S, Albeverio S, Assis P E G, Azizov T Y, Bender C M, Bender C M, Bender C M, Caliceti E, Caliceti E, Cycon H L, Dijksma A, Dorey P, Fring A, Glazman I M, Graefe E-M, Günther U, Japaridze G S, Kiyosi Itô, Knapp A W, Kuzhel A Kuzhel S, Kuzhel S, Levai G, Mostafazadeh A, PHHQP, Physics of non-Hermitian operators, Reed M, S Albeverio, S Kuzhel, Scholtz F G, Smilga A V, Tanaka T, U Günther, Vilenkin N Y   +34 more
core   +1 more source

The Mathematical History Behind the Granger–Johansen Representation Theorem

Oxford Bulletin of Economics and Statistics, EarlyView.
ABSTRACT When can a vector time series that is integrated once (i.e., becomes stationary after taking first differences) be described in error correction form? The answer to this is provided by the Granger–Johansen representation theorem. From a mathematical point of view, the theorem can be viewed as essentially a statement concerning the geometry of ...
Johannes M. Schumacher
wiley   +1 more source

The nonlocal problem for the $2n$ differential equations with unbounded operator coefficients and the involution

Karpatsʹkì Matematičnì Publìkacìï, 2018
We study a problem with periodic boundary conditions for a $2n$-order differential equation whose coefficients are non-self-adjoint operators. It is established that the operator of the problem has two invariant subspaces generated by the involution ...
Ya.O. Baranetskij, I.I. Demkiv, I.Ya. Ivasiuk, M.I. Kopach   +3 more
doaj   +1 more source

Quantum singularity of Levi-Civita spacetimes

, 2004
Quantum singularities in general relativistic spacetimes are determined by the behavior of quantum test particles. A static spacetime is quantum mechanically singular if the spatial portion of the wave operator is not essentially self-adjoint.
Bonnor W B, C Wieland, D A Konkowski, Ellis G F R, Gautreau R, Hawking S W, Helliwell T M, Herrera L, Herrera L, Horowitz G T, Ishibashi A, Kay B S, Levi-Civita T, Reed M, Reed M, Richmyer R-D, T M Helliwell, von Neumann J, Wald R M, Weyl H   +19 more
core   +2 more sources

On MAP Estimates and Source Conditions for Drift Identification in SDEs

Proceedings in Applied Mathematics and Mechanics, Volume 26, Issue 2, June 2026.
ABSTRACT We consider the inverse problem of identifying the drift in an stochastic differential equation (SDE) from n$n$ observations of its solution at M+1$M+1$ distinct time points. We derive a corresponding maximum a posteriori (MAP) estimate, we prove differentiability properties as well as a so‐called tangential cone condition for the forward ...
Daniel Tenbrinck, Nikolas Uesseler, Philipp Wacker, Benedikt Wirth   +3 more
wiley   +1 more source

Solution of certain problem with nonlocal boundary condition for one-dimensional wave equation

Вестник Самарского университета: Естественнонаучная серия
In this paper, we study a problem with nonlocal boundary condition for one-dimensional wave equation. To prove the solvability of the problem we construct biortogonal basis consisting of eigen- and adjoint-functions of not self adjoint operator.
Elvira E. Gasanova, Ludmila S. Pulkina
doaj   +1 more source

The Regularized Trace Formula Of A Second Order Differentıal Equation Given With Anti-Perıodic Boundary Conditions

Cumhuriyet Science Journal, 2019
In this study, we examined the formula of the regularizedtrace of the self-adjoint operator which is formed bydifferentialexpression and anti-periodic boundary condition.
Seda Kızılbudak Çalışkan, Leyla Özen   +1 more
doaj   +1 more source

Unbounded quantum graphs with unbounded boundary conditions

, 2012
We consider metric graphs with a uniform lower bound on the edge lengths but no further restrictions. We discuss how to describe every local self-adjoint Laplace operator on such graphs by boundary conditions in the vertices given by projections and self-
Adams, Arens, Berkolaiko, Brüning, Buschmann, Carlson, Carlson, Cheon, Derkach, Everitt, Exner, Harmer, Kostenko, Kostrykin, Kostrykin, Kuchment, Post, Schubert   +17 more
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Iterative Krylov Subspace Methods for Linear Port‐Hamiltonian Systems

Proceedings in Applied Mathematics and Mechanics, Volume 26, Issue 2, June 2026.
ABSTRACT In this work, we present a structure‐preserving Krylov subspace iteration scheme for solving the equation systems that arise from the Gauss integration of linear energy‐conserving and dissipative differential systems (e.g., Poisson systems, gradient systems, and port‐Hamiltonian systems).
Stefan Maier, Nicole Marheineke
wiley   +1 more source

Correspondence of the eigenvalues of a non-self-adjoint operator to those of a self-adjoint operator

, 2008
We prove that the eigenvalues of a certain highly non-self-adjoint operator that arises in fluid mechanics correspond, up to scaling by a positive constant, to those of a self-adjoint operator with compact resolvent; hence there are infinitely many real ...
Burkill, Dunford, John Weir
core   +1 more source