Abstract
Gershgorin’s famous circle theorem states that all eigenvalues of a square matrix lie in disks (called Gershgorin disks) around the diagonal elements. Here we show that if the matrix entries are non-negative and an eigenvalue has geometric multiplicity at least two, then this eigenvalue lies in a smaller disk. The proof uses geometric rearrangement inequalities on sums of higher dimensional real vectors which is another new result of this paper.
Dedicated to the memory of Jiří Matoušek
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References
A. Berman, R.J. Plemmons, Nonnegative Matrices in the Mathematical Sciences (SIAM, Philadelphia, 1994)
G.M. Del Corso, Estimating an eigenvector by the power method with a random start. SIAM. J. Matrix Anal. Appl. 18, 913–937 (1997)
M. Fiedler, F.J. Hall, R. Marsli, Gershgorin discs revisited. J. Linear Algebra Appl. 438, 598–603 (2013)
S. Gerschgorin, Über die Abgrenzung der Eigenwerte einer Matrix. Izv. Akad. Nauk. USSR Otd. Fiz.-Mat. Nauk 6, 749–754 (1931)
O. Hesse, Über die Wendepunkte der Curven dritter Ordnung. J. Reine Angew. Math. 28, 97–102 (1844)
L. Lovász, Steinitz Representations of Polyhedra and the Colin de Verdière Number. J. Combin. Theory B 82, 223–236 (2001)
R. Marsli, F.J. Hall, Geometric multiplicities and Gershgorin discs. Am. Math. Mon. 120, 452–455 (2013)
R. Marsli, F.J. Hall, Some refinements of Gershgorin discs. Int. J. Algebra 7, 573–580 (2013)
R. Marsli, F.J. Hall, Further results on Gershgorin discs. J. Linear Algebra Appl. 439, 189–195 (2013)
R. Marsli, F.J. Hall, Some new inequalities on geometric multiplicities and Gershgorin discs. Int. J. Algebra 8, 135–147 (2014)
P. McMullen, Transforms, diagrams and representations, in Contributions to Geometry. Proceedings of the Geometry-Symposium, Siegen, 1978 (Birkhäuser, Basel/Boston, 1979), pp. 92–130
A. Roy, Minimal Euclidean representations of graphs. Discret. Math. 310, 727–733 (2010)
J.M. Steele, The Cauchy-Schwarz Master Class. An Introduction to the Art of Mathematical Inequalities (Cambridge University Press, New York, 2004)
H. van der Holst, L. Lovász, A. Schrijver, The Colin de Verdière graph parameter, in Graph Theory and Combinatorial Biology. Bolyai Society Mathematical Studies, vol. 7 (János Bolyai Mathematical Society, Budapest, 1999), pp. 29–85
R.S. Varga, Gershgorin and His Circles (Springer, Berlin, 2004)
Acknowledgements
This research was supported by ERC Advanced Research Grant no 267165 (DISCONV). Imre Bárány is partially supported by Hungarian National Research Grant K 111827. József Solymosi is partially supported by Hungarian National Research Grant NK 104183 and by an NSERC Discovery Grant. We are indebted to three anonymous referees for very useful comments and information that have improved the presentation of this paper.
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Bárány, I., Solymosi, J. (2017). Gershgorin Disks for Multiple Eigenvalues of Non-negative Matrices. In: Loebl, M., Nešetřil, J., Thomas, R. (eds) A Journey Through Discrete Mathematics. Springer, Cham. https://doi.org/10.1007/978-3-319-44479-6_6
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DOI: https://doi.org/10.1007/978-3-319-44479-6_6
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