>>120
つづき
下記論文を、 27 Aug 2019に投稿しているね
(this is also inspired by Mochizuki's results)などと記されている
https://arxiv.org/abs/1906.06840
Mochizuki's anabelian variation of ring structures and formal groups
Kirti Joshi
(last revised 27 Aug 2019 (this version, v2))
(抜粋)
I show that there is a universal formal group (over a suitable (non-zero) ring) which is equipped with an action of the multiplicative monoid O? of non-zero elements of the ring of integers of a p-adic field.
Lubin-Tate formal groups also arise from this universal formal group.
If two p-adic fields have isomorphic multiplicative monoids O? then the additive structure of one arises from that of the other by means of this universal formal group law (in a suitable manner).
In particular if two p-adic fields have isomorphic absolute Galois groups then it is well-known that the two respective monoids O? are isomorphic and so this construction can be applied to such p-adic fields.
In this sense this universal formal group law provides a single additive structure which binds together p-adic fields whose absolute Galois groups are isomorphic
(this anabelian variation of ring structure is studied and used extensively by Shinichi Mochizuki).
In particular one obtains a universal (additive) expression for any non-zero p-adic integer (in a given p-adic field) which is independent of the ring structure of the p-adic field (this is also inspired by Mochizuki's results).
These ideas extend to geometric situations: for a smooth curve X/K there is a universal K(X)?-formal group (here K(X)? is the monoid of non-zero meromorphic functions on a smooth curve X/K over a p-adic field K, which binds together all the additive structures on K(X)?∪{0} compatibly with the universal additive structure on K?∪{0}
and hence a non-zero meromorphic function on X is given by a universal additive expression which is independent of the ring structure of K(X)?∪{0}