Abstract
The definitions of the nth Gauss sum and the associated nth central charge are introduced for premodular categories \(\mathcal {C}\) and \(n\in \mathbb {Z}\). We first derive an expression of the nth Gauss sum of a modular category \(\mathcal {C}\), for any integer n coprime to the order of the T-matrix of \(\mathcal {C}\), in terms of the first Gauss sum, the global dimension, the twist and their Galois conjugates. As a consequence, we show for these n, the higher Gauss sums are d-numbers and the associated central charges are roots of unity. In particular, if \(\mathcal {C}\) is the Drinfeld center of a spherical fusion category, then these higher central charges are 1. We obtain another expression of higher Gauss sums for de-equivariantization and local module constructions of appropriate premodular and modular categories. These expressions are then applied to prove the Witt invariance of higher central charges for pseudounitary modular categories.
Similar content being viewed by others
References
Anderson, G., Moore, G.: Rationality in conformal field theory. Commun. Math. Phys. 117(3), 441–450 (1988)
Bakalov, B., Kirillov Jr., A.: Lectures on Tensor Categories and Modular Functors. Volume 21 of University Lecture Series. American Mathematical Society, Providence, RI (2001)
Bantay, P.: The Frobenius–Schur indicator in conformal field theory. Phys. Lett. B 394(1–2), 87–88 (1997)
Bruillard, P., Ng, S.-H., Rowell, E.C., Wang, Z.: Rank-finiteness for modular categories. J. Am. Math. Soc. 29(3), 857–881 (2016)
Calegari, F., Morrison, S., Snyder, N.: Cyclotomic integers, fusion categories, and subfactors. Commun. Math. Phys. 303(3), 845–896 (2011)
Coste, A., Gannon, T.: Remarks on Galois symmetry in rational conformal field theories. Phys. Lett. B 323(3–4), 316–321 (1994)
Davydov, A., Müger, M., Nikshych, D., Ostrik, V.: The Witt group of non-degenerate braided fusion categories. J. Reine Angew. Math. 677, 135–177 (2013)
Davydov, A., Nikshych, D., Ostrik, V.: On the structure of the Witt group of braided fusion categories. Sel. Math. 19(1), 237–269 (2013)
de Boer, J., Goeree, J.: Markov traces and \({\rm II}_1\) factors in conformal field theory. Commun. Math. Phys. 139(2), 267–304 (1991)
Dong, C., Lin, X., Ng, S.-H.: Congruence property in conformal field theory. Algebra Number Theory 9(9), 2121–2166 (2015)
Drinfeld, V., Gelaki, S., Nikshych, D., Ostrik, V.: On braided fusion categories. I. Sel. Math. (N.S.) 16(1), 1–119 (2010)
Eilenberg, S., MacLane, S.: Cohomology theory of Abelian groups and homotopy theory. I. Proc. Natl. Acad. Sci. USA 36, 443–447 (1950)
Eilenberg, S., MacLane, S.: Cohomology theory of Abelian groups and homotopy theory. II. Proc. Natl. Acad. Sci. USA 36, 657–663 (1950)
Etingof, P., Gelaki, S., Nikshych, D., Ostrik, V.: Tensor Categories. Volume 205 of Mathematical Surveys and Monographs. American Mathematical Society, Providence, RI (2015)
Etingof, P., Nikshych, D., Ostrik, V.: On fusion categories. Ann. Math. (2) 162(2), 581–642 (2005)
Etingof, P., Ostrik, V.: On semisimplification of tensor categories. arXiv:1801.04409
Evans, D.E., Gannon, T.: The exoticness and realisability of twisted Haagerup–Izumi modular data. Commun. Math. Phys. 307(2), 463–512 (2011)
Gauss, C.F.: Summatio serierum quarundam singularium. Comment. Soc. Regiae Sci. Gott. 1 (1811)
Gauss, C.F.: Disquisitiones arithmeticae (Trans. into English by Arthur A. Clarke, S. J.). Yale University Press, New Haven, Conn.-London (1966)
Greiter, G.: A simple proof for a theorem of Kronecker. Am. Math. Mon. 85(9), 756–757 (1978)
Ireland, K., Rosen, M.: A Classical Introduction to Modern Number Theory. Volume 84 of Graduate Texts in Mathematics, 2nd edn. Springer, New York (1990)
Kashina, Y., Montgomery, S., Ng, S.-H.: On the trace of the antipode and higher indicators. Isr. J. Math. 188, 57–89 (2012)
Kashina, Y., Sommerhäuser, Y., Zhu, Y.: On higher Frobenius–Schur indicators. Mem. Am. Math. Soc. 181(855), viii+65 (2006)
Kač, V.G., Peterson, D.H.: Infinite-dimensional lie algebras, theta functions and modular forms. Adv. Math. 53(2), 125–264 (1984)
Kirby, R., Melvin, P.: The \(3\)-manifold invariants of Witten and Reshetikhin–Turaev for \({\rm sl}(2,{ C})\). Invent. Math. 105(3), 473–545 (1991)
Kirillov, A., Ostrik, V.: On a \(q\)-analogue of the McKay correspondence and the ADE classification of \(\mathfrak{sl}_2\) conformal field theories. Adv. Math. 171(2), 183–227 (2002)
Lang, S.: Algebra. Volume 211 of Graduate Texts in Mathematics, 3rd edn. Springer, New York (2002)
Lejeune Dirichlet, G.: Recherches sur diverses applications de l’Analyse infinitésimale à la Théorie des Nombres. Seconde Partie. J. Reine Angew. Math. 21, 134–155 (1840)
Lickorish, W.B.R.: Invariants for \(3\)-manifolds from the combinatorics of the Jones polynomial. Pac. J. Math. 149(2), 337–347 (1991)
Linchenko, V., Montgomery, S.: A Frobenius–Schur theorem for Hopf algebras. Algebr. Represent. Theory 3(4), 347–355 (2000). (Special issue dedicated to Klaus Roggenkamp on the occasion of his 60th birthday)
Lusztig, G.: Introduction to Quantum Groups, Modern Birkhäuser Classics. Birkhäuser, Boston (2010)
Müger, M.: From subfactors to categories and topology. II. The quantum double of tensor categories and subfactors. J. Pure Appl. Algebra 180(1–2), 159–219 (2003)
Murakami, H., Ohtsuki, T., Okada, M.: Invariants of three-manifolds derived from linking matrices of framed links. Osaka J. Math. 29(3), 545–572 (1992)
Ng, S.-H., Schauenburg, P.: Frobenius–Schur indicators and exponents of spherical categories. Adv. Math. 211(1), 34–71 (2007)
Ng, S.-H., Schauenburg, P.: Higher Frobenius–Schur indicators for pivotal categories. In: Hopf algebras and generalizations. Contemporary Mathematics, vol. 441, pp. 63–90. American Mathematical Society, Providence, RI (2007)
Ng, S.-H., Schauenburg, P.: Central invariants and higher indicators for semisimple quasi-Hopf algebras. Trans. Am. Math. Soc. 360(4), 1839–1860 (2008)
Ng, S.-H., Schauenburg, P.: Congruence subgroups and generalized Frobenius–Schur indicators. Commun. Math. Phys. 300(1), 1–46 (2010)
Ostrik, V.: On formal codegrees of fusion categories. Math. Res. Lett. 16(5), 895–901 (2009)
Ostrik, V.: Pivotal fusion categories of rank 3. Mosc. Math. J. 15(2), 373–396 (2015)
Pareigis, B.: On braiding and dyslexia. J. Algebra 171, 413–425 (1995)
Penneys, D., Tener, J.E.: Subfactors of index less than 5, part 4: vines. Int. J. Math. 23(3), 18 (2012)
Reshetikhin, N., Turaev, V.G.: Invariants of \(3\)-manifolds via link polynomials and quantum groups. Invent. Math. 103(3), 547–597 (1991)
Rowell, E.C.: From quantum groups to unitary modular tensor categories. Contemp. Math. 413, 215–230 (2006)
Rowell, E.C., Wang, Z.: Mathematics of topological quantum computing. Bull. Am. Math. Soc. (N.S.) 55(2), 183–238 (2018)
Scharlau, W.: Quadratic and Hermitian Forms, Volume 270 of Grundlehren der Mathematischen Wissenschaften [Fundamental Principles of Mathematical Sciences]. Springer, Berlin (1985)
Schopieray, A.: Classification of \(\mathfrak{sl}_3\) relations in the Witt group of nondegenerate braided fusion categories. Commun. Math. Phys. 353(3), 1103–1127 (2017)
Schopieray, A.: Level bounds for exceptional quantum subgroups in rank two. Int. J. Math. 29(5), 1850034 (2018)
Schopieray, A: Prime decomposition of modular tensor categories of local modules of Type D. arXiv:1810.09057
Shimizu, K.: Frobenius–Schur indicators in Tambara–Yamagami categories. J. Algebra 332, 543–564 (2011)
Shimizu, K.: Some computations of Frobenius–Schur indicators of the regular representations of Hopf algebras. Algebr. Represent. Theory 15(2), 325–357 (2012)
Tambara, D., Yamagami, S.: Tensor categories with fusion rules of self-duality for finite abelian groups. J. Algebra 209(2), 692–707 (1998)
Tucker, H.: Frobenius–Schur indicators for near-group and Haagerup–Izumi fusion categories. Pac. J. Math. arXiv:1510.05696
Turaev, V.: Reciprocity for Gauss sums on finite abelian groups. Math. Proc. Cambr. Philos. Soc. 124(2), 205–214 (1998)
Turaev, V.G.: Quantum Invariants of Knots and 3-Manifolds. Volume 18 of De Gruyter Studies in Mathematics, revised edn. Walter de Gruyter & Co., Berlin (2010)
Vafa, C.: Toward classification of conformal theories. Phys. Lett. B 206(3), 421–426 (1988)
Vaughan, S.M., Jones, F.R., Snyder, N.: The classification of subfactors of index at most 5. Bull. Am. Math. Soc. 51(2), 277–327 (2014)
Wan, Z., Wang, Y.: Classification of spherical fusion categories of Frobenius–Schur exponent 2. Algebra Colloq. arXiv:1811.02004
Wang, Z.: Topological Quantum Computation, Volume 112 of CBMS Regional Conference Series in Mathematics. Published for the Conference Board of the Mathematical Sciences, Washington, DC. American Mathematical Society, Providence, RI (2010)
Witten, E.: Quantum field theory and the Jones polynomial. Commun. Math. Phys. 121(3), 351–399 (1989)
Acknowledgements
The second author would like to thank Victor Ostrik for his suggestion to explore the notion of higher Gauss sums. Both the second and third authors would like to thank MSRI (Summer Graduate School 791) for providing the opportunity to initiate this collaboration. The third author would like to thank Thomas Kerler and James Cogdell, and the first author would like to thank Ling Long for fruitful discussions.
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
The first author was partially supported by NSF DMS1664418.