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Tate \(\gamma \)-factor, Weil index, and the metaplectic \(\widetilde{\gamma }\) -factor

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Abstract

Let \(F\) be a p-adic field, let \(\psi \) be a non-trivial character of F, and let \(\chi \) be a character of \(F^*\). In this short note we present two new identities involving \(\gamma (s,\chi ,\psi )\), \(\gamma (\psi )\), and \(\widetilde{\gamma }(s,\chi ,\psi )\) along with a duplication formula for \(\gamma (s,\chi ,\psi )\). Here \({\gamma }(s,\chi ,\psi )\) is the Tate \(\gamma \)-factor, \(\gamma (\psi )\) is the Weil index, and \(\widetilde{\gamma }(s,\chi ,\psi )\) is the metaplectic \(\widetilde{\gamma }\)-factor. As a result we give a new proof for a useful identity involving these three factors originally proven by W. Jay Sweet.

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References

  1. Adrian, M., Kaplan, E.: The Langlands parameter of a simple supercuspidal representation: symplectic groups. Ramanujan J. 50(3), 589–619 (2019)

    Article  MathSciNet  Google Scholar 

  2. Bump, D.: Automorphic Forms and Representations. Cambridge Studies in Advanced Mathematics. Cambridge University Press, Cambridge (1997)

    Book  Google Scholar 

  3. Cogdell, J.W., Kim, H.H., Murty, M.R.: Lectures on Automorphic L-Functions. Fields Institute Monographs, vol. 20. American Mathematical Society, Providence, RI (2004)

    Google Scholar 

  4. Frahm, J., Kaplan, E.: A Godement-Jacquet type integral and the metaplectic Shalika model. Am. J. Math. 141(1), 219–282 (2019)

    Article  MathSciNet  Google Scholar 

  5. Gao, F., Shahidi, F., Szpruch, D.: On the local coefficients matrix for coverings of SL2. In Geometry, algebra, number theory, and their information technology applications, vol. 251 of Springer Proc. Math. Stat. Springer, Cham, pp. 207–244 (2018)

  6. Gao, F., Shahidi, F., Szpruch, D.: Local coefficients and gamma factors for principal series of covering groups. arXiv:1902.02686. 118 pp. To appear in the Memoirs of the American Mathematical Society (2019)

  7. Godement, R., Jacquet, H.: Zeta Functions of Simple Algebras. Lecture Notes in Mathematics. Springer, Berlin-New York (1972)

    Book  Google Scholar 

  8. Goldberg, D., Szpruch, D.: Plancherel measures for coverings of p-adic SL2(F). Int. J. Number Theory 12(7), 1907–1936 (2016)

    Article  MathSciNet  Google Scholar 

  9. Ichino, A.: Pullbacks of Saito–Kurokawa lifts. Invent. Math. 162(3), 551–647 (2005)

    Article  MathSciNet  Google Scholar 

  10. Jacquet, H., Langlands, R.P.: Automorphic Forms on GL(2). Lecture Notes in Mathematics. Springer, Berlin (1970)

    MATH  Google Scholar 

  11. Jacquet, H., Piatetskii-Shapiro, I.I., Shalika, J.A.: Rankin–Selberg convolutions. Am. J. Math. 105(2), 367–464 (1983)

    Article  MathSciNet  Google Scholar 

  12. Kahn, B.: Le groupe des classes modulo 2, d’aprÈs Conner et Perlis. In Seminar on number theory, 1984–1985 (Talence, 1984/1985). Univ. Bordeaux I, Talence, 1985, pp. Exp. No. 26, 29

  13. Kahn, B.: Sommes de Gauss attachées aux caractères quadratiques: une conjecture de Pierre Conner. Comment. Math. Helv. 62(4), 532–541 (1987)

    Article  MathSciNet  Google Scholar 

  14. Lang, S.: Algebraic Number Theory, Graduate Texts in Mathematics, vol. 110. Springer, New York (1994)

    Book  Google Scholar 

  15. Nelson, P.D.: Subconvex equidistribution of cusp forms: reduction to Eisenstein observables. Duke Math. J. 168(9), 1665–1722 (2019)

    Article  MathSciNet  Google Scholar 

  16. Shahidi, F.: Local coefficients as Artin factors for real groups. Duke Math. J. 52(4), 973–1007 (1985)

    Article  MathSciNet  Google Scholar 

  17. Sweet, J.: Functional equations of p-adic zeta integrals and representations of the metaplectic group. (1995)

  18. Sweet Jr., W.J.: A computation of the gamma matrix of a family of p-adic zeta integrals. J. Number Theory 55(2), 222–260 (1995)

    Article  MathSciNet  Google Scholar 

  19. Szpruch, D.: On the existence of a p-adic metaplectic Tate-type -factor. Ramanujan J. 26(1), 45–53 (2011)

    Article  MathSciNet  Google Scholar 

  20. Szpruch, D.: Some irreducibility theorems of parabolic induction on the metaplectic group via the Langlands–Shahidi method. Israel J. Math. 195(2), 897–971 (2013)

    Article  MathSciNet  Google Scholar 

  21. Szpruch, D.: A short proof for the relation between Weil indices and \(\epsilon \)-factors. Commun. Algebra 46(7), 2846–2851 (2018)

    Article  MathSciNet  Google Scholar 

  22. Szpruch, D.: On Shahidi local coefficients matrix. Manuscripta Math. 159(1–2), 117–159 (2019)

    Article  MathSciNet  Google Scholar 

  23. Tate, J. T.: Fourier analysis in number fields, and Hecke’s zeta-functions. In Algebraic Number Theory (Proc. Instructional Conf., Brighton, 1965). Thompson, Washington, D.C., pp. 305–347 (1967)

  24. Weil, A.: Sur certains groupes d’opérateurs unitaires. Acta Math. 111, 143–211 (1964)

    Article  MathSciNet  Google Scholar 

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Acknowledgements

We would like to thank Freydoon Shahidi and Fan Gao. The contents of this note emanated from our joint work. We would also like to thank Eyal Kaplan for his valuable comments on the subject matter.

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Correspondence to Dani Szpruch.

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Szpruch, D. Tate \(\gamma \)-factor, Weil index, and the metaplectic \(\widetilde{\gamma }\) -factor. Ramanujan J 57, 697–706 (2022). https://doi.org/10.1007/s11139-021-00399-7

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