Article
Keywords:
Artin $L$-function; character; Galois Gauss sum; special value
Summary:
We give a simple proof that critical values of any Artin $L$-function attached to a representation $\rho $ with character $\chi _{\rho }$ are stable under twisting by a totally even character $\chi $, up to the $\dim \rho $-th power of the Gauss sum related to $\chi $ and an element in the field generated by the values of $\chi _{\rho }$ and $\chi $ over $\mathbb {Q}$. This extends a result of Coates and Lichtenbaum as well as the previous work of Ward.
References:
                        
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