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Timeline for On the pole of local L-function

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Aug 23, 2014 at 9:32 vote accept Monty
Aug 23, 2014 at 9:32 comment added Monty @GHfromMO, Thanks again. I will try to read the book you recommend.
Aug 23, 2014 at 8:36 comment added GH from MO @classnumb: The statement in your second sentence is false. Indeed, for every nonzero complex number $s$, the function $\chi=|\cdot|^s$ on $\mathbb{A}^{\times}/F$ is a nontrivial Hecke character. On the other hand, the statement in Bump's book is true, it is a special case of Corollary 2 in Section VII.3 of Weil: Basic number theory. I recommend studying Sections VII.3 and VII.4 in Weil's book. Also, for new questions you might have, open a new question at MathOverflow (i.e. do not ask further questions as comments here).
Aug 23, 2014 at 5:58 comment added Monty On the other hand, may I ask one another question? When $\chi$ is a nontrivial Hecke character of $\mathbb{A}^{\times}/F$ , then how do we know that there is no complex number $s$ such that $\chi \ne |\cdot|^s$ ? Because in the bump's book, it says that every quasi character $\chi$ of $\mathbb{A}^{\times}/F$ is a product of a unitary Hecke character $\chi_1$ and $|\cdot|^s$ for some complex $s$.
Aug 23, 2014 at 5:57 comment added Monty Thanks for your clear answer. As you recommeded, I have read Tate's thesis contatined in Bump's book. And I learned that the above local L-function is the same form obtained from the meromorphic continuation of local zeta integral when the test function is the characteristic function. And so I think if $\chi$ is a Hecke character, the $L_v(\chi_v,x)$ would have no pole for $Re(s) >0$ and it may have pole only at $\Re(s)=0$. Your remark that the pole of global L-function do not pertains to that of local L-function is striking to me. I confused it for a long time. Thanks for your illumination.
Aug 21, 2014 at 12:50 comment added GH from MO @paulgarrett: I agree, but of course the epsilon factors combine nicely!
Aug 21, 2014 at 12:47 comment added paul garrett Another, similar, common misconception is that "local functional equations" should combine to give the "global functional equation", and this is not the case.
Aug 21, 2014 at 8:32 history edited GH from MO CC BY-SA 3.0
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Aug 21, 2014 at 8:24 history answered GH from MO CC BY-SA 3.0