Abstract
New eigenvalue enclosures for the block operator problem arising in the study of stability of the Ekman boundary layer are proved. This solves an open problem in [19] on the existence of open sets of eigenvalues in domains of Fredholmness of the analyzed operator family.
Similar content being viewed by others
References
Abramov, A.A., Aslanyan, A., Davies, E.B.: Bounds on complex eigenvalues and resonances. J. Phys. A Math. Gen. 34, 57 (2001)
Bögli, S., Marletta, M., Tretter, C.: The essential numerical range for unbounded linear operators. J. Funct. Anal. 279, 108509 (2020)
Boulton, L., Krejčiřík, D., Siegl, P.: Non-self-adjoint portal. http://nsa.fjfi.cvut.cz
Cassano, B., Ibrogimov, O.O., Krejčiřík, D., Štampach, F.: Location of eigenvalues of non-self-adjoint discrete dirac operators. Ann. Henri Poincaré 21, 2193–2217 (2020)
Conway, J.B.: Functions of One Complex Variable, 2nd edn. Springer, New York-Berlin (1978)
Cossetti, L.: Bounds on eigenvalues of perturbed Lamé operators with complex potentials. Math. Eng. 4, 1–29 (2021)
Cuenin, J.-C.: Estimates on complex eigenvalues for Dirac operators on the half-line. Integral Equ. Oper. Theory 79, 377–388 (2014)
Cuenin, J.-C.: Eigenvalue bounds for Dirac and fractional Schrödinger operators with complex potentials. J. Funct. Anal. 272, 2987–3018 (2017)
Cuenin, J.-C.: Sharp spectral estimates for the perturbed landau hamiltonian with \(L^p\) potentials. Integral Equ. Oper. Theory 88, 127–141 (2017)
Cuenin, J.-C.: Improved eigenvalue bounds for Schrödinger operators with slowly decaying potentials. Commun. Math. Phys. 376, 2147–2160 (2019)
Cuenin, J.-C., Laptev, A., Tretter, C.: Eigenvalue estimates for non-selfadjoint dirac operators on the real line. Ann. Henri Poincaré 15, 707–736 (2014)
Davies, E., Nath, J.: Schrödinger operators with slowly decaying potentials. J. Comput. Appl. Math. 148, 1–28 (2002)
Faller, A.J.: An experimental study of the instability of the laminar Ekman boundary layer. J. Fluid Mech. 15, 560–576 (1963)
Fanelli, L., Krejčiřík, D., Vega, L.: Spectral stability of Schrödinger operators with subordinated complex potentials. J. Spectr. Theory 8, 575–604 (2018)
Frank, R., Simon, B.: Eigenvalue bounds for Schrödinger operators with complex potentials. II. J. Spectr. Theory 7, 633–658 (2017)
Frank, R.L.: Eigenvalue bounds for Schrödinger operators with complex potentials. Bull. Lond. Math. Soc. 43, 745–750 (2011)
Frank, R.L.: Eigenvalue bounds for Schrödinger operators with complex potentials. III. Trans. Am. Math. Soc. 370, 219–240 (2017)
Gesztesy, F., Latushkin, Y., Mitrea, M., Zinchenko, M.: Nonselfadjoint operators, infinite determinants, and some applications. Russ. J. Math. Phys. 12, 443–471 (2005)
Greenberg, L., Marletta, M.: The Ekman flow and related problems: spectral theory and numerical analysis. Math. Proc. Cambridge Philos. Soc. 136, 719–764 (2004)
Kato, T.: Perturbation Theory for Linear Operators. Springer, Berlin (1995)
Laptev, A., Safronov, O.: Eigenvalue estimates for Schrödinger operators with complex potentials. Commun. Math. Phys. 292, 29–54 (2009)
Lilly, D.K.: On the instability of Ekman boundary flow. J. Atmos. Sci. 23, 481–494 (1966)
Marletta, M., Tretter, C.: Essential spectra of coupled systems of differential equations and applications in hydrodynamics. J. Differ. Equ. 243, 36–69 (2007)
Spooner, G.F.: Continuous temporal eigenvalue spectrum of an Ekman boundary layer. Phys. Fluids 25, 1958–1963 (1982)
Vladimirov, V.S.: Equations of Mathematical Physics. Marcel Dekker Inc, New York (1971)
Vladimirov, V.S.: Methods of the Theory of Generalized Functions. Taylor & Francis, London (2002)
Author information
Authors and Affiliations
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
B.G. expresses her gratitude to her supervisor C. Tretter for drawing her attention to this problem and to the Queen’s University Belfast for their hospitality during a SEMP doctoral student exchange in 2019/20. O.I. is grateful to G.M. Graf for fruitful discussions and thanks the Institute for Theoretical Physics at ETH Zurich for the kind hospitality through a postdoctoral researcher position. P.S. acknowledges the support and hospitality of the Institute for Theoretical Physics, ETH Zurich, during his visit there in July 2019 when this project was initiated.
Rights and permissions
About this article
Cite this article
Gerhat, B., Ibrogimov, O.O. & Siegl, P. On the Point Spectrum in the Ekman Boundary Layer Problem. Commun. Math. Phys. 392, 377–397 (2022). https://doi.org/10.1007/s00220-022-04321-0
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00220-022-04321-0