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Non-lifting idempotents in the quotient category overline{h𝒯_∞}(T^*M)

Determine whether there exists an idempotent in the quotient category \overline{h𝒯_∞}(T^*M) (obtained by modding out morphisms of infinite spectral value) that does not lift to an idempotent in h𝒯_∞(T^*M); equivalently, construct such an example or prove that every idempotent in \overline{h𝒯_∞}(T^*M) lifts.

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Background

To refine statements about spectral invariants, the paper introduces a 1-category \overline{h𝒯_∞}(T*M) by quotienting morphisms whose spectral value c(βˆ’; F, G) is +∞. In reasonable cases this quotient coincides with the original homotopy category, but in general it need not.

While idempotents in hπ’―βˆž(T*M) induce idempotents in the quotient, it is unknown whether there exist genuinely new idempotents in the quotient that do not come from hπ’―βˆž(T*M). Resolving this would clarify whether the quotient introduces additional splitting phenomena not present in the original category.

References

However the author do not know an example of idempotents in $\overline{h\cT_\infty}(T*M)$ which does not lift to that of $h\cT_\infty(T*M)$.

Heavy subsets from microsupports (2404.15556 - Asano, 23 Apr 2024) in Remark following Corollary 4.1 (in Subsection 4.1, Criteria for ΞΆ_e-heaviness)