Zobrazeno 1 - 10
of 696
pro vyhledávání: '"Ransford, P."'
We show how a Cram\'er-Wold theorem for a family of multivariate probability distributions can be used to generate a similar theorem for mixtures (convex combinations) of distributions drawn from the same family. Using this abstract result, we establ
Externí odkaz:
http://arxiv.org/abs/2410.22038
The Crouzeix ratio $\psi(A)$ of an $N\times N$ complex matrix $A$ is the supremum of $\|p(A)\|$ taken over all polynomials $p$ such that $|p|\le 1$ on the numerical range of $A$. It is known that $\psi(A)\le 1+\sqrt{2}$, and it is conjectured that $\
Externí odkaz:
http://arxiv.org/abs/2409.14127
Publikováno v:
Linear Algebra and its Applications 703 (2024), 20-26
Let $T$ be a injective bounded linear operator on a complex Hilbert space. We characterize the complex numbers $\lambda,\mu$ for which $(I+\lambda T)(I+\mu T)^{-1}$ is a contraction, the characterization being expressed in terms of the numerical rang
Externí odkaz:
http://arxiv.org/abs/2409.14125
Given a compact convex planar domain $\Omega$ with non-empty interior, the classical Neumann's configuration constant $c_{\mathbb{R}}(\Omega)$ is the norm of the Neumann-Poincar\'e operator $K_\Omega$ acting on the space of continuous real-valued fun
Externí odkaz:
http://arxiv.org/abs/2407.19049
We study the real and imaginary parts of the powers of the Volterra operator on $L^2[0,1]$, specifically their eigenvalues, their norms and their numerical ranges.
Comment: 10 pages
Comment: 10 pages
Externí odkaz:
http://arxiv.org/abs/2402.09287
Autor:
Ransford, Julian
We consider a simplified model of first-passage percolation, involving two families of i.i.d. random variables $\{\xi_{ij}\}$ and $\{\eta_{ij}\}$ corresponding to the weights of the horizontal and vertical edges respectively. We obtain an explicit fo
Externí odkaz:
http://arxiv.org/abs/2401.06759
Autor:
Ransford, Thomas
We show that, given a closed subset $E$ of the unit circle of Lebesgue measure zero, there exists a positive sequence $u_n\to\infty$ with the following property: if $T$ is a Hilbert-space contraction such that $\sigma(T)\subset E$ and $\|T^{-n}\|=O(u
Externí odkaz:
http://arxiv.org/abs/2310.10754
Autor:
Hémery, Kévin, Ghanem, Khaldoon, Crane, Eleanor, Campbell, Sara L., Dreiling, Joan M., Figgatt, Caroline, Foltz, Cameron, Gaebler, John P., Johansen, Jacob, Mills, Michael, Moses, Steven A., Pino, Juan M., Ransford, Anthony, Rowe, Mary, Siegfried, Peter, Stutz, Russell P., Dreyer, Henrik, Schuckert, Alexander, Nigmatullin, Ramil
Publikováno v:
PRX Quantum 5, 030323 (2023)
Calculating the equilibrium properties of condensed matter systems is one of the promising applications of near-term quantum computing. Recently, hybrid quantum-classical time-series algorithms have been proposed to efficiently extract these properti
Externí odkaz:
http://arxiv.org/abs/2309.10552
It is known that there exist functions in certain de Branges--Rovnyak spaces whose Taylor series diverge in norm, even though polynomials are dense in the space. This is often proved by showing that the sequence of Taylor partial sums is unbounded in
Externí odkaz:
http://arxiv.org/abs/2305.05716
Autor:
Moses, S. A., Baldwin, C. H., Allman, M. S., Ancona, R., Ascarrunz, L., Barnes, C., Bartolotta, J., Bjork, B., Blanchard, P., Bohn, M., Bohnet, J. G., Brown, N. C., Burdick, N. Q., Burton, W. C., Campbell, S. L., Campora III, J. P., Carron, C., Chambers, J., Chan, J. W., Chen, Y. H., Chernoguzov, A., Chertkov, E., Colina, J., Curtis, J. P., Daniel, R., DeCross, M., Deen, D., Delaney, C., Dreiling, J. M., Ertsgaard, C. T., Esposito, J., Estey, B., Fabrikant, M., Figgatt, C., Foltz, C., Foss-Feig, M., Francois, D., Gaebler, J. P., Gatterman, T. M., Gilbreth, C. N., Giles, J., Glynn, E., Hall, A., Hankin, A. M., Hansen, A., Hayes, D., Higashi, B., Hoffman, I. M., Horning, B., Hout, J. J., Jacobs, R., Johansen, J., Jones, L., Karcz, J., Klein, T., Lauria, P., Lee, P., Liefer, D., Lytle, C., Lu, S. T., Lucchetti, D., Malm, A., Matheny, M., Mathewson, B., Mayer, K., Miller, D. B., Mills, M., Neyenhuis, B., Nugent, L., Olson, S., Parks, J., Price, G. N., Price, Z., Pugh, M., Ransford, A., Reed, A. P., Roman, C., Rowe, M., Ryan-Anderson, C., Sanders, S., Sedlacek, J., Shevchuk, P., Siegfried, P., Skripka, T., Spaun, B., Sprenkle, R. T., Stutz, R. P., Swallows, M., Tobey, R. I., Tran, A., Tran, T., Vogt, E., Volin, C., Walker, J., Zolot, A. M., Pino, J. M.
Publikováno v:
Phys. Rev. X 13, 041052 (2023)
We describe and benchmark a new quantum charge-coupled device (QCCD) trapped-ion quantum computer based on a linear trap with periodic boundary conditions, which resembles a race track. The new system successfully incorporates several technologies cr
Externí odkaz:
http://arxiv.org/abs/2305.03828