An introduction to p-adic L-functions — Lean blueprint

3. Measures and the Iwasawa algebra🔗

This chapter develops the p-adic analysis underlying the whole story: p-adic measures on a profinite abelian group G, their identification with the Iwasawa algebra \Lam(G), and — in the key case G = \Zp — a fourth description as power series via the Mahler transform. We then build a toolbox of operations on measures, introduce pseudo-measures (to accommodate the simple pole of the zeta function), and close with locally analytic distributions. The treatment follows Jacinto and Williams (2023) §3.

Throughout we fix a finite extension L of \Qp, with p-adic valuation \vp normalised by \vp(p) = 1; this is the coefficient field, and \OL denotes its ring of integers.

  1. 3.1. Preliminaries on p-adic Banach spaces
  2. 3.2. p-adic measures
  3. 3.3. The Iwasawa algebra
  4. 3.4. p-adic analysis and Mahler transforms
  5. 3.5. A measure-theoretic toolbox
  6. 3.6. Pseudo-measures
  7. 3.7. Locally analytic functions and distributions