Audenaert–Datta conjecture on the full joint convexity range

At least 7 years old · documented by

Let MN\mathcal M_N denote the set of complex N×NN\times N matrices and PN\mathcal P_N the subset of positive definite matrices. For p,q∈Rp,q\in\mathbb R, s>0s>0, and K∈MNK\in\mathcal M_N, define

PN×PN∋(A,B)↦Tr⁡(Bq/2K∗ApKBq/2)s.\mathcal P_N\times\mathcal P_N\ni(A,B)\mapsto\operatorname{Tr}\left(B^{q/2}K^*A^pKB^{q/2}\right)^s.

Audenaert–Datta conjecture. If 1≤p≤21\leq p\leq2, −1≤q<0-1\leq q<0, and s≥1/(p+q)s\geq1/(p+q), then this map is jointly convex. These conditions complement the necessary conditions stated in the source and conjecturally give the sufficient range for joint convexity.

References

Primary source

Eric A. Carlen, Rupert L. Frank and Elliott H. Lieb, “Inequalities for quantum divergences and the Audenaert-Datta conjecture”, arXiv:1806.03985 (2018).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.