geometry-topology / Stable homotopy theory

Curtis's conjecture: the mod-2 stable Hurewicz image of the sphere is spanned by the Hopf- and Kervaire-invariant-one classes

Theorem 1.1: the image of ⨁d>0hd\bigoplus_{d>0}h_d is spanned over F2\mathbb F_2 by the Hurewicz images of η,ν,σ\eta,\nu,\sigma and of the Kervaire-invariant-one classes θj\theta_j (degree 2j+1−22^{j+1}-2) whenever they exist; no existence is posited. Corollary 1.2: Eccles's conjecture holds for every sphere SnS^n, n>0n>0: each nonzero spherical class in H∗(QSn;F2)H_*(QS^n;\mathbb F_2) is the bottom class or a suspended Hopf-invariant-one image. Corollary 1.3 (with Hill-Hopkins-Ravenel): hd=0h_d=0 for d>0d>0 outside {1,2,3,6,7,14,30,62,126}\{1,2,3,6,7,14,30,62,126\}, so the positive image vanishes above degree 126. Not shown: an exact dimension of the image or nonvanishing in each listed degree, odd primes, or Eccles's conjecture for QXQX with XX other than a sphere.

48Significance / 100
1Frontier events
0Verification tasks
0Recorded attempts

Temporal state

Current frontier

No reconciled state yet.

Append-only history

Frontier timeline

geometry-topologySep 25, 2026Significance 48/100Registry: unreviewed

Curtis's conjecture: the mod-2 stable Hurewicz image of the sphere is spanned by the Hopf- and Kervaire-invariant-one classes

Prior state unknown→proved

Theorem 1.1: the image of ⨁d>0hd\bigoplus_{d>0}h_d is spanned over F2\mathbb F_2 by the Hurewicz images of η,ν,σ\eta,\nu,\sigma and of the Kervaire-invariant-one classes θj\theta_j (degree 2j+1−22^{j+1}-2) whenever they exist; no existence is posited. Corollary 1.2: Eccles's conjecture holds for every sphere SnS^n, n>0n>0: each nonzero spherical class in H∗(QSn;F2)H_*(QS^n;\mathbb F_2) is the bottom class or a suspended Hopf-invariant-…

SourceReplayReproducedFormal proofStatement auditExternal checkExpert reviewPeer review

Research memory

Claims and attempts

Scoped claims

Source authenticated

Theorem 1.1: the image of ⨁d>0hd\bigoplus_{d>0}h_d is spanned over F2\mathbb F_2 by the Hurewicz images of η,ν,σ\eta,\nu,\sigma and of the Kervaire-invariant-one classes θj\theta_j (degree 2j+1−22^{j+1}-2) whenever they exist; no existence is posited. Corollary 1.2: Eccles's conjecture holds for every sphere SnS^n, n>0n>0: each nonzero spherical class in H∗(QSn;F2)H_*(QS^n;\mathbb F_2) is the bottom class or a suspended Hopf-invariant-one image. Corollary 1.3 (with Hill-Hopkins-Ravenel): hd=0h_d=0 for d>0d>0 outside {1,2,3,6,7,14,30,62,126}\{1,2,3,6,7,14,30,62,126\}, so the positive image vanishes above degree 126. Not shown: an exact dimension of the image or nonvanishing in each listed degree, odd primes, or Eccles's conjecture for QXQX with XX other than a sphere.

Theorem 1.1: the image of ⨁d>0hd\bigoplus_{d>0}h_d is spanned over F2\mathbb F_2 by the Hurewicz images of η,ν,σ\eta,\nu,\sigma and of the Kervaire-invariant-one classes θj\theta_j (degree 2j+1−22^{j+1}-2) whenever they exist; no existence is posited. Corollary 1.2: Eccles's conjecture holds for every sphere SnS^n, n>0n>0: each nonzero spherical class in H∗(QSn;F2)H_*(QS^n;\mathbb F_2) is the bottom class or a suspended Hopf-invariant-one image. Corollary 1.3 (with Hill-Hopkins-Ravenel): hd=0h_d=0 for d>0d>0 outside {1,2,3,6,7,14,30,62,126}\{1,2,3,6,7,14,30,62,126\}, so the positive image vanishes above degree 126. Not shown: an exact dimension of the image or nonvanishing in each listed degree, odd primes, or Eccles's conjecture for QXQX with XX other than a sphere.

Recorded attempts

Evidence graph

Connected research record

Curtis's conjecture: the mod-2 stable Hurewicz image of the sphere is spanned by the Hopf- and Kervaire-invariant-one classes — Mathematical Frontier Network