Identification of the index-theoretic and homotopy-theoretic MU-local systems

Prove that the Thom spectrum associated to the homotopy-theoretically defined MU-local system \(\Sigma^{-\dim Q}\widetilde V\otimes\epsilon\) on \(LQ\) is equivalent to the Thom spectrum associated to the index-theoretic MU-local system \(\Sigma^{-\dim Q}V\otimes\epsilon\), namely establish \((LQ)^{\Sigma^{-\dim Q}\widetilde V\otimes\epsilon}\simeq(LQ)^{\Sigma^{-\dim Q}V\otimes\epsilon}\).

Background

The paper defines a candidate local system V~\widetilde V by applying the free-loop construction to the stable tangent bundle classifying map [TQ]:QBO[TQ]:Q\to\mathrm{BO}, then mapping through LBOΩBOOBGL1(MU)L\mathrm{BO}\to\Omega\mathrm{BO}\simeq\mathrm O\to\mathrm{BGL}_1(\mathrm{MU}). This construction is intended to provide the homotopy-theoretic counterpart of the index-theoretically constructed local system VV.

The conjecture asks whether the two resulting Thom spectra agree after including the dimension shift and the auxiliary local system ϵ\epsilon. Establishing this would give the desired homotopy-theoretic interpretation of the MU-local system used in the MU-Viterbo isomorphism.

References

We have that (L Q){\Sigma{-\dim Q}\widetilde{V}\otimes\epsilon}\simeq(L Q){\Sigma{-\dim Q}V\otimes\epsilon}.

Spectral Viterbo isomorphism: complex-oriented versus framed  (2608.20289 - Blakey, 20 Aug 2026) in Conjecture 1.3, Section 1.3 (Speculations and symmetry-breaking), subsection Speculations