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Timeline for Easy cases of Herbrand's theorem

Current License: CC BY-SA 4.0

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Nov 18, 2018 at 3:28 comment added user131093 Short answer: No, there is no "easy" way to prove that $V_{p-2} = 0$. And yes, there is an easy way to prove $V_1 = 0$ --- as Sawin says, Kummer theory says any such Galois extension (without any ramification conditions) is of the form $\mathbf{Q}(\zeta_p, N^{1/p})$ where $N \in \mathbf{Q}$, at which point it is easy to see (using unique factorization) that all such extensions are ramified.
Nov 16, 2018 at 1:59 comment added Will Sawin It should be possible to calculate one of $V_1$ or $V_{-1}$ (and therefore show it vanishes I guess) by Kummer theory.
S Nov 16, 2018 at 1:40 history suggested user130124 CC BY-SA 4.0
nonzero should read zero (clearly, for instance $V$ is zero when $p$ is a regular prime).
Nov 15, 2018 at 21:41 review Suggested edits
S Nov 16, 2018 at 1:40
Nov 15, 2018 at 20:17 history edited David E Speyer CC BY-SA 4.0
added 307 characters in body
Nov 15, 2018 at 20:10 history asked David E Speyer CC BY-SA 4.0