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Equality G^{0} = G^{00} and virtual algebraicity for definable groups over C((t))

Prove that for every group G definable in the valued field C((t)), the definable connected component G^{0} equals the smallest type-definable subgroup G^{00} of bounded index; consequently, show that G has a finite-index subgroup that is an open subgroup of an algebraic group over C((t)).

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Background

The relationship between G{0} and G{00} is central in the model-theoretic analysis of definable groups, often driving structural classification and connections to algebraic groups. In p-adically closed fields, equality results lead to strong algebraicity consequences (e.g., [7]).

The authors conjecture that the same phenomenon holds over C((t)), implying that definable groups are virtually algebraic in the sense of containing a finite-index subgroup that is open in an algebraic group over C((t)).

References

Conjecture 4.3. Let G be a group defined in C((t)). Then G0 = G00. Consequently (like Corollary 4.3 [7]), G is virtually an open subgroup of an algebraic group over C((t)).

A short note on model theory of C((t)) (2501.12545 - Zhang, 21 Jan 2025) in Conjecture 4.3, Section 4 (More results)