Archiv der Mathematik

, Volume 96, Issue 3, pp 235–245 | Cite as

On a hybrid bound for twisted L-values

  • Ritabrata Munshi


Let f S k (M, ψ) be a newform, and let χ be a primitive character of conductor q. We express \({L(\frac{1}{2}+it,f\otimes\chi)}\) as a short combination of bilinear forms involving Kloosterman fractions. Using this we establish the convexity breaking bound \({L\left(\tfrac{1}{2}+it,f\otimes\chi\right)\ll_{f,\varepsilon} [q(1+|t|)]^{\frac{1}{2}-\frac{1}{118}+\varepsilon}}\) for any ε > 0.

Mathematics Subject Classification (2010)

Primary 11F66 Secondary 11M41 


L-functions Subconvexity Hybrid bound 


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Copyright information

© Springer Basel AG 2011

Authors and Affiliations

  1. 1.School of MathematicsTata Institute of Fundamental ResearchMumbaiIndia

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