Local root numbers for heisenberg-representations – Some explicit results
Article, International Journal of Mathematics, 2021, DOI Link
View abstract ⏷
Heisenberg representations ρ of (pro-)finite groups G are by definition irreducible representations of the two-step nilpotent factor group G/C3G. Better known are Heisenberg groups which can be understood as allowing faithful Heisenberg representations. A special feature is that ρ = IndHG(χ H) will be induced by characters (H,χH) of subgroups in multiple ways, where the pairs (H,χH) can be interpreted as maximal isotropic pairs. If F|ℚp is a p-adic number field and G = GF the absolute Galois group then maximal isotropic pairs rewrite as (E,χE), where E|F is an abelian extension and χE:E×→ ℂ× a character. We will consider the extended local Artin-root-number W(ρ,ψ) for those ρ which are essentially tame and express it by a formula not depending on the various maximal isotropic pairs (E,χE) for ρ.
Epsilon factors of symplectic type characters in the wild case
Article, Forum Mathematicum, 2021, DOI Link
View abstract ⏷
By work of John Tate we can associate an epsilon factor with every multiplicative character of a local field. In this paper, we determine the explicit signs of the epsilon factors for symplectic type characters of K×, where K/F is a wildly ramified quadratic extension of a non-Archimedean local field F of characteristic zero.
Langlands lambda function for quadratic tamely ramified extensions
Article, Journal of Algebra and its Applications, 2019, DOI Link
View abstract ⏷
Let K/F be a quadratic tamely ramified extension of a non-Archimedean local field F of characteristic zero. In this paper, we give an explicit formula for Langlands' lambda function λK/F.
Computation of the Lambda function for a finite Galois extension
Article, Journal of Number Theory, 2018, DOI Link
View abstract ⏷
By Langlands [13], and Deligne [4] we know that the local constants are extendible functions. Therefore, to give an explicit formula of the local constant of an induced representation of a local Galois group of a non-Archimedean local field F of characteristic zero, we have to compute the lambda function λK/F for a finite extension K/F. In this paper, when a finite extension K/F is Galois, we give a formula for λK/F.
Invariant formula of the determinant of a Heisenberg representation
Article, International Journal of Mathematics, 2017, DOI Link
View abstract ⏷
In this paper, we give an explicit formula of the determinant of a Heisenberg representation ρ of a finite group G. Heisenberg representations are induced by 1-dimensional characters in multiple ways, but our formula will be independent of any particular choice of induction.
Twisting formula of epsilon factors
Article, Proceedings of the Indian Academy of Sciences: Mathematical Sciences, 2017, DOI Link
View abstract ⏷
For characters of a non-Archimedean local field we have explicit formula for epsilon factors. But in general, we do not have any generalized twisting formula of epsilon factors. In this paper, we give a generalized twisting formula of epsilon factors via local Jacobi sums.