Search results

SetRel: Examples don't show why α → β → Prop is worse than SetRel α β

Status: Open.

#39397 In leanprover-community/mathlib4;

· OrfeasLitos opened on May 14, 2026

Nonexistent SetRel.map in example

Status: Open.

#39396 In leanprover-community/mathlib4;

· OrfeasLitos opened on May 14, 2026

API development for LanguageOn in symbolic dynamics

Status: Open.

#39252 In leanprover-community/mathlib4;

· Sfgangloff opened on May 12, 2026

Formalization of various notions of convergence

Status: Open.

#39125 In leanprover-community/mathlib4;

· LLyaudet opened on May 9, 2026

Feature Request: Schur complement for block matrices and singular value bounds

Status: Open.

#38808 In leanprover-community/mathlib4;

· rnoisil-prog opened on May 1, 2026

Make scripts/add_deprecations.sh support additivised declarations

enhancementNew feature or requestNew feature or request

good first issueGood for newcomersGood for newcomers

Status: Open.

#38550 In leanprover-community/mathlib4;

· YaelDillies opened on Apr 26, 2026

Weak spaces as a class

Status: Open.

#38484 In leanprover-community/mathlib4;

· j-loreaux opened on Apr 24, 2026

Stability under finite-rank perturbation of strict linear maps with closed range

enhancementNew feature or requestNew feature or request

t-analysisAnalysis (normed *, calculus)Analysis (normed *, calculus)

t-topologyTopological spaces, uniform spaces, metric spaces, filtersTopological spaces, uniform spaces, metric spaces, filters

Status: Open.

Task

#38471 In leanprover-community/mathlib4;

· ADedecker opened on Apr 24, 2026

Define Fredholm operators

enhancementNew feature or requestNew feature or request

t-analysisAnalysis (normed *, calculus)Analysis (normed *, calculus)

t-topologyTopological spaces, uniform spaces, metric spaces, filtersTopological spaces, uniform spaces, metric spaces, filters

Status: Open.

Feature

#38460 In leanprover-community/mathlib4;

· ADedecker opened on Apr 24, 2026

Strict group homs are stable by Prod.map

enhancementNew feature or requestNew feature or request

good first issueGood for newcomersGood for newcomers

t-topologyTopological spaces, uniform spaces, metric spaces, filtersTopological spaces, uniform spaces, metric spaces, filters

Status: Open.

Feature

#38421 In leanprover-community/mathlib4;

· ADedecker opened on Apr 23, 2026

Analytic Hahn Banach theorem for locally convex settings

enhancementNew feature or requestNew feature or request

good first issueGood for newcomersGood for newcomers

t-analysisAnalysis (normed *, calculus)Analysis (normed *, calculus)

t-topologyTopological spaces, uniform spaces, metric spaces, filtersTopological spaces, uniform spaces, metric spaces, filters

Status: Open.

Feature

#38419 In leanprover-community/mathlib4;

· ADedecker opened on Apr 23, 2026

Define Submodule.IsTopologicalCompl

enhancementNew feature or requestNew feature or request

good first issueGood for newcomersGood for newcomers

t-analysisAnalysis (normed *, calculus)Analysis (normed *, calculus)

t-topologyTopological spaces, uniform spaces, metric spaces, filtersTopological spaces, uniform spaces, metric spaces, filters

Status: Open.

Feature

#38416 In leanprover-community/mathlib4;

· ADedecker opened on Apr 23, 2026