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Related papers: Time delay for the Dirac equation

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A sharp condition is provided to guarantee that the (nontrivial) solutions of a DDE of the form $\dot{x}(t)+F(t,x)=0$ $t\geq 0,$ (where $F(t,\cdot)$ is an odd-like causal operator) either oscillate, or converge monotonically to zero. The…

Dynamical Systems · Mathematics 2025-08-20 George L. Karakostas

A new time-delay estimation (TDE) technique based on dynamic programming is developed, to measures the time-varying time-delay between two signals. Dynamic programming based TDE technique provides a frequency response 5 to 10 times higher…

Plasma Physics · Physics 2010-01-11 Deepak K. Gupta , George R. McKee , Raymond R. Fonck

We establish rates of convergences in time series forecasting using the statistical learning approach based on oracle inequalities. A series of papers extends the oracle inequalities obtained for iid observations to time series under weak…

Statistics Theory · Mathematics 2012-11-12 Pierre Alquier , Xiaoyin Li , Olivier Wintenberger

The global existence and stability of the solution to the delay differential equation (*)$\dot{u} = A(t)u + G(t,u(t-\tau)) + f(t)$, $t\ge 0$, $u(t) = v(t)$, $-\tau \le t\le 0$, are studied. Here $A(t):\mathcal{H}\to \mathcal{H}$ is a…

Functional Analysis · Mathematics 2020-12-15 N. S. Hoang , A. G. Ramm

An elementary treatment of the Dirac Equation in the presence of a three-dimensional spherically symmetric $\delta (r-r_0)$-potential is presented. We show how to handle the matching conditions in the configuration space, and discuss the…

Quantum Physics · Physics 2009-11-06 R. Benguria , H. Castillo , M. Loewe

An approximation Ansatz for the operator solution, $U(z',z)$, of a hyperbolic first-order pseudodifferential equation, $\d_z + a(z,x,D_x)$ with $\Re (a) \geq 0$, is constructed as the composition of global Fourier integral operators with…

Analysis of PDEs · Mathematics 2007-05-23 Jerome Le Rousseau

The WS time delay matrix relates a lossless and reciprocal system's scattering matrix to its frequency derivative, and enables the synthesis of modes that experience well-defined group delays when interacting with the system. The elements…

Computational Physics · Physics 2021-07-28 Utkarsh R. Patel , Eric Michielssen

We estimate asymptotically the fourth moment of the Riemann zeta-function twisted by a Dirichlet polynomial of length $T^{\frac14 - \varepsilon}$. Our work relies crucially on Watt's theorem on averages of Kloosterman fractions. In the…

Number Theory · Mathematics 2016-09-09 Sandro Bettin , H. M. Bui , Xiannan Li , Maksym Radziwiłł

The missed particle-antiparticle degrees of freedom are retrieved and the corresponding particle-antiparticle intrinsic space are introduced to study the dynamical symmetry of the Dirac particle. As a result, the particle-antiparticle…

High Energy Physics - Theory · Physics 2007-05-23 Shun-Jin Wang , Shan-Gui Zhou , Hans-Christian Pauli

In this paper, we propose a new approach for stochastic control problems arising from utility maximization. The main idea is to directly start from the dynamical programming equation and compute the conditional expectation using a novel…

Mathematical Finance · Quantitative Finance 2022-02-28 Jingtang Ma , Zhengyang Lu , Zhenyu Cui

A perturbation decaying to 0 at infinity and not too irregular at 0 introduces at most a discrete set of eigenvalues into the spectral gaps of a one-dimensional Dirac operator on the half-line. We show that the number of these eigenvalues…

Spectral Theory · Mathematics 2007-05-23 Karl Michael Schmidt

This Letter is based on the $\kappa$-Dirac equation, derived from the $\kappa$-Poincar\'{e}-Hopf algebra. It is shown that the $\kappa$-Dirac equation preserves parity while breaks charge conjugation and time reversal symmetries.…

High Energy Physics - Theory · Physics 2014-03-21 F. M. Andrade , E. O. Silva , M. M. Ferreira , E. C. Rodrigues

The idea of dissipative mechanical system with delay is proposed. The paper studies the phenomenon of dissipation with delay for Euler-Poincare systems on Lie algebras or equivalently, for Lie-Poisson systems on the duals of Lie algebras.…

Dynamical Systems · Mathematics 2007-05-23 I. D. Albu , M. Neamtu , D. Opris

We have obtained the metric operator $\Theta=\exp T$ for the non-Hermitian Hamiltonian model $H=\omega(a^{\dag}a+1/2)+\alpha(a^{2}-a^{\dag^{2}})$. We have also found the intertwining operator which connects the Hamiltonian to the adjoint of…

Mathematical Physics · Physics 2014-06-13 Özlem Yeşiltaş , Nafiye Kaplan

We present four frequently used finite difference methods and establish the error bounds for the discretization of the Dirac equation in the massless and nonrelativistic regime, involving a small dimensionless parameter $0< \varepsilon \ll…

Numerical Analysis · Mathematics 2021-05-03 Ying Ma , Jia Yin

Hamiltonian operators are gauge dependent. For overcome this difficulty we reexamined the effect of a gauge transformation on Schr\"odinger and Dirac equations. We show that the gauge invariance of the operator…

Mathematical Physics · Physics 2012-08-14 J. A. Sánchez-Monroy , John Morales , Eduardo Zambrano

We consider a second order linear equation with a time-dependent coefficient c(t) in front of the "elastic" operator. For these equations it is well-known that a higher space-regularity of initial data compensates a lower time-regularity of…

Analysis of PDEs · Mathematics 2014-08-18 Marina Ghisi , Massimo Gobbino

We present a new method for time delay estimation using band limited frequency domain data representing the port responses of interconnect structures. The approach is based on the recently developed by the authors spectrally accurate method…

Numerical Analysis · Mathematics 2015-08-25 Lyudmyla L. Barannyk , Hung H. Tran , Aicha Elshabini , Fred D. Barlow

We discuss the emergence of time dilation as a normal feature expected of any system where a central processor may have to wait one or more clock cycles before concluding a local calculation. We show how the process of causal implication in…

General Relativity and Quantum Cosmology · Physics 2009-09-25 George Jaroszkiewicz

Using Baker-Campbell-Hausdorff relations, the squeeze and harmonic-oscillator time-displacement operators are given in the form $\exp[\delta I] \exp[\alpha (x^2)]\exp[\beta(x\partial)] \exp[\gamma (\partial)^2]$, where $\alpha$, $\beta$,…

Quantum Physics · Physics 2016-09-08 Michael Martin Nieto
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