Cyclotomy and endomotives

Abstract

Abstract. We compare two different models of noncommutative geometry of the cyclotomic tower, both based on an arithmetic algebra of functions of roots of unity and an action by endomorphisms, the first based on the Bost-Connes (BC) quantum statistical mechanical system and the second on the Habiro ring, where the Habiro functions have, in addition to evaluations at roots of unity, also full Taylor expansions. Both have compatible endomorphisms actions of the multiplicative semigroup of positive integers. As a higher dimensional generalization, we consider a crossed product ring obtained using Manin's multivariable generalizations of the Habiro functions and an action by endomorphisms of the semigroup of integer matrices with positive determinant. We then construct a corresponding class of multivariable BC endomotives, which are obtained geometrically from self maps of higher dimensional algebraic tori, and we discuss some of their quantum statistical mechanical properties. These multivariable BC endomotives are universal for (torsion free) Λ-rings, compatibly with the Frobenius action. Finally, we discuss briefly how Habiro's universal Witten-Reshetikhin-Turaev invariant of integral homology 3-spheres may relate invariants of 3-manifolds to gadgets over F1 and semigroup actions on homology 3-spheres to endomotives.

The BC-system and L-functions

“…[39]) a ƒ-ring whose Frobenius endomorphisms agree with the basic endomorphisms n . Our first goal is to relate this ƒ-ring with the canonical ƒ-ring W 0 .…”

“…N F p / of an algebraic closure N F p of F p . As shown in [39] the abelian part of the integral BC-system is naturally a ƒ-ring whose Frobenius endomorphisms agree with the basic endomorphisms defining the system. In §3 we prove that, if one drops the p-component, the full structure of the integral BC-system is completely described as W 0 .…”

Thermodynamic semirings

“…These can naturally be described within the setting of Λ-rings (see [36]). This seems especially useful, in view of the whole approach to F 1 geometry based on Λ-rings, developed by James Borger in [7] and [8], [9] (see also [32], [33] for other related viewpoints).…”

Torified varieties and their geometries over $${\mathbb{F}_1}$$

“…In recent years, a number of papers ( [2][3][4][5][6][7][19][20][21]23,25], …) on the topic have appeared, dealing mostly with the problem of defining a suitable notion of algebraic geometry over such an elusive object. Several non equivalent approaches have been tried, for instance Durov (cf.…”