R202, Astronomy-Mathematics Building, NTU
(台灣大學天文數學館 202室)
The Mordell-Weil Theorem for t-modules
Yen-Liang Kuan (NCTS)
Abstract:
For each positive characteristic multiple zeta value (defined by Thakur)
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, Chang-Papanikolas-Yu constructed the

-module

defined over

and integral points

,
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. They proved that
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is Eulerian (resp. zeta-like) if and only if

is an

-torsion point in
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(resp.

,

are

-linearly dependent in
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).
In this talk, we are interested in the structure theory of the

-module
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. Poonen proved an analogue for Drinfeld modules of the Mordell-Weil theorem. We shall generalize his results to the case of specific families of

-modules. In particular, we prove that the

-module
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is the direct sum of its torsion submodule, which is finite, with a free

-module of rank

.