Abstract
We study differential operators on complete Riemannian manifolds which act on sections of a bundle of finite type modules over a von Neumann algebra with a trace. We prove a relative index and a Callias-type index theorem for von Neumann indexes of such operators. We apply these results to obtain a version of Atiyah’s \(L^2\)-index theorem, which states that the index of a Callias-type operator on a non-compact manifold M is equal to the \(\Gamma \)-index of its lift to a Galois cover of M. We also prove the cobordism invariance of the index of Callias-type operators. In particular, we give a new proof of the cobordism invariance of the von Neumann index of operators on compact manifolds.
Similar content being viewed by others
Notes
In other words in this section we assume that \(A=\mathbb {C}\). We use the notation S (rather than \(\Sigma \)) for the Dirac bundle, to stress the difference from the other sections where \(\Sigma \) was a Hilbert A-bundle.
References
Anghel, N.: \(L^2\)-index formulae for perturbed Dirac operators. Commun. Math. Phys. 128(1), 77–97 (1990)
Anghel, N.: On the index of Callias-type operators. Geom. Funct. Anal. 3(5), 431–438 (1993)
Atiyah, M.: Elliptic operators, discrete groups and von Neumann algebras. Astèrisque, 32-33 (1976)
Atiyah, M.F., Singer, I.M.: The index of elliptic operators on compact manifolds. Bull. Am. Math. Soc. 69, 422–433 (1963)
Berline, N., Getzler, E., Vergne, M.: Heat Kernels and Dirac Operators. Springer, Berlin (1992)
Booß-Bavnbek, B., Wojciechowski, K.P.: Elliptic Boundary Problems for Dirac Operators. Princeton Mathematical Series. Birkhäuser, Boston (1993)
Bott, R., Seeley, R.: Some remarks on the paper of Callias: “Axial anomalies and index theorems on open spaces” [Comm. Math. Phys. 62 (1978), no. 3, 213–234; MR 80h:58045a]. Commun. Math. Phys. 62(3), 235–245 (1978)
Braverman, M.: Index theorem for equivariant Dirac operators on noncompact manifolds. \(K\)-Theory 27(1), 61–101 (2002)
Braverman, M.: Cobordism invariance of the index of a transversely elliptic operator, volume 98 of Appendix J in the book “Moment Maps, Cobordisms, and Hamiltonian Group Actions” by V. L. Ginzburg and V. Guillemin and Y. Karshon. Mathematical Surveys and Monographs. American Mathematical Society, Providence, RI (2002)
Braverman, M.: New proof of the cobordism invariance of the index. Proc. Am. Math. Soc. 130(4), 1095–1101 (2002)
Braverman, M.: The index theory on non-compact manifolds with proper group action. J. Geom. Phys. 98, 275–284 (2015)
Braverman, M., Cano, L.: Index Theory for Non-compact \(G\)-Manifolds. Geometric. Algebraic and Topological Methods for Quantum Field Theory, pp. 60–94. World Scientific Publishing, Hackensack (2014)
Braverman, M., Cecchini, S.: Spectral theory of von Neumann algebra valued differential operators over non-compact manifolds. J. Noncommutative Geom. 10(4), 1589–1609 (2016)
Braverman, M., Shi, P.: Cobordism invariance of the index of Callias-type operators. Comm. Partial Differ. Equ. 41(8), 1183–1203 (2016)
Breuer, M.: Fredholm theories in von Neumann algebras. I. Math. Ann. 178, 243–254 (1968)
Breuer, M.: Fredholm theories in von Neumann algebras. II. Math. Ann. 180, 313–325 (1969)
Brüning, J., Moscovici, H.: \(L^2\)-index for certain Dirac–Schrödinger operators. Duke Math. J. 66(2), 311–336 (1992)
Bunke, U.: A K-theoretic relative index theorem and Callias-type Dirac operators. Math. Ann. 303(2), 241–280 (1995)
Bunke, U.: On the Index of Equivariant Toeplitz Operators. Lie Theory and Its Applications in Physics. III (Clausthal, 1999), pp. 176–184. World Scientific Publishing, River Edge (2000)
Callias, C.: Axial anomalies and index theorems on open spaces. Commun. Math. Phys. 62(3), 213–235 (1978)
Carvalho, C.: A \(K\)-theory proof of the cobordism invariance of the index. \(K\)-Theory 36(1–2), 1–31 (2005)
Carvalho, C., Nistor, V.: An index formula for perturbed Dirac operators on Lie manifolds. J Geom. Anal. 24(4), 1808–1843 (2014)
Carvalho, C.: Cobordism invariance of the family index. Math. Nachr. 285(7), 808–820 (2012)
Cecchini, S.: Callias-type operators in \(C^*\) -algebras and positive scalar curvature on noncompact manifolds. 11 (2016)
Fomenko, A.T., Miščenko, A.S.: The index of elliptic operators over \({C}^*\)-algebras. Math. USSR Izv. 15(1), 87–112 (1980)
Ginzburg, V.L., Guillemin, V., Karshon, Y.: Cobordism theory and localization formulas for Hamiltonian group actions. Int. Math. Res. Not. 5, 221–234 (1996)
Gromov, M., Lawson, H.B.: Positive scalar curvature and the Dirac operator on complete riemannian manifolds. Publications Mathmatiques de l’Institut des Hautes tudes Scientifiques 58(1), 83–196 (1983)
Guillemin, V., Ginzburg, V., Karshon, Y.: Moment maps, cobordisms, and Hamiltonian group actions. Mathematical Surveys and Monographs, vol. 98. American Mathematical Society, Providence, RI, Appendix J by Maxim Braverman (2002)
Higson, N.: A note on the cobordism invariance of the index. Topology 30(3), 439–443 (1991)
Hilsum, M.: Bordism invariance in \(KK\)-theory. Math. Scand. 107(1), 73–89 (2010)
Hitchin, N.: Harmonic spinors. Adv. Math. 14, 1–55 (1974)
Kottke, C.: An index theorem of Callias type for pseudodifferential operators. J. K-Theory 8(3), 387–417 (2011)
Kottke, C.: A Callias-type index theorem with degenerate potentials. Commun. Partial Differ. Equ. 40(2), 219–264 (2015)
Lawson, H.B., Michelsohn, M.L.: Spin Geometry. Princeton Mathematical Series. Princeton University Press, Princeton (1989)
Lück, W.: \(L^2\)-Invariants: Theory and Applications to Geometry and K-Theory. A Series of Modern Surveys in Mathematics Series. Springer, Berlin (2002)
Nistor, V.: On the kernel of the equivariant Dirac operator. Ann. Glob. Anal. Geom. 17(6), 595–613 (1999)
Palais, R.S.: Seminar on the Atiyah-Singer index theorem. Annals of Mathematics Studies, No. 57, Princeton University Press, Princeton (1965)
Schick, T.: \(L^2\)-index theorems, KK-theory, and connections. N Y J Math 11, 387–443 (2005)
Wimmer, R.: An index for confined monopoles. Commun. Math. Phys. 327(1), 117–149 (2014)
Acknowledgements
M. Braverman was supported in part by the NSF Grant DMS-1005888.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Braverman, M., Cecchini, S. Callias-Type Operators in von Neumann Algebras. J Geom Anal 28, 546–586 (2018). https://doi.org/10.1007/s12220-017-9832-1
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12220-017-9832-1