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arXiv · 2506.03829

Isomorphism of \'etale fundamental groups lifts to isomorphism of stratified fundamental group

Indranil Biswas·Manish Kumar·A. J. Parameswaran
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Abstract

It is shown that if a finite generically smooth morphism $f\,:\,Y\,\longrightarrow\, X$ of smooth projective varieties induces an isomorphism of the \'etale fundamental groups, then the induced map of the stratified fundamental groups $\pi_1^{str}(f)\, :\, \pi_1^{str}(Y,\, y)\,\longrightarrow\, \pi_1^{str}(X,\, f(y))$ is also an isomorphism.

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Indranil Biswas, Manish Kumar, A. J. Parameswaran. 2025-06-04. Isomorphism of \'etale fundamental groups lifts to isomorphism of stratified fundamental group. https://arxiv.org/abs/2506.03829

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