Gromov width of Katok ellipsoids

Determine the Gromov width of the almost toric ellipsoids \(E_{2;1,1}(\alpha,\beta)\) and \(E_{2,1}(\alpha,\beta)\), equivalently the corresponding Katok ellipsoid domains associated with \(S^2\) and \(\mathbb{R}P^2\).

Background

The paper identifies E2;1,1(α,β)E_{2;1,1}(\alpha,\beta) with the unit codisc bundles of the Randers metrics inducing Katok’s examples on S2S^2, and identifies E2,1(α,β)E_{2,1}(\alpha,\beta) with the analogous domains associated with RP2\mathbb{R}P^2. It computes their embedding regions into the relevant compact targets and establishes staircase structures.

The Gromov width is known in the round cases, namely for the ball-shaped domains B2;1,1(λ)B_{2;1,1}(\lambda) and B2,1(λ)B_{2,1}(\lambda), but the general two-parameter computation remains unresolved in the paper and is noted as a subject of forthcoming work.

References

Another natural question is whether the Gromov width $c_{\mathrm{Gr}$ of the ellipsoids $E_{2;1,1}(\alpha,\beta)$ and $E_{2,1}(\alpha,\beta)$ can be computed.

— Quantitative symplectic topology of Katok's examples and equivariant symplectic embeddings  (2609.35209 - Adaloglou et al., 28 Sep 2026) in Section 2, subsection “Ellipsoidal domains in cotangent bundles,” Remark following Corollary 2.??