Mathematics Problem Archive
Branch points of area-minimizing surfaces
v1.3 research notes1. Does ${\rm Sing}_b (T)$ have zero $(m-1)$-dimensional Hausdorff measure? 2. If yes, does ${\rm Sing}_b (T)$ have (Hausdorff) dimension at most $m-2...
Manifolds modelled on flag manifolds
v1.3 research notesWhich manifolds can be modeled on an orbit of a real form in a space of flags?...
Manifolds modelled on flag manifolds — Question 2
v1.3 research notesWhat is the homotopy classification of totally real immersions of real $3$-manifolds in the complex full flag manifold $F_{12}$?...
Bi-invariant metrics and multiplicity of conjugate points
v1.3 research notesAssume that a left-invariant Riemannian metric is given on a compact connected Lie group $G$ such that the index of any geodesic segment is even. Must...
Toral manifolds and positive scalar curvature
v1.3 research notesLet $M$ be a connected closed manifold with finite fundamental group of odd order. Assume that the universal cover of $M$ admits a metric of positive ...
Toral manifolds and positive scalar curvature — Question 2
v1.3 research notesLet $M$ be a connected closed manifold admitting a metric of positive scalar curvature. Does this imply that $M$ is $p$-atoral for all odd $p$?...
Coarse embeddings
v1.3 research notesFind more numerical invariants of metric spaces that are nondecreasing under coarse embeddings....
Coarse embeddings — Question 2
v1.3 research notesFind applications of the harmonic map approximation of coarse embeddings....
Classification problems and Poisson structures
v1.3 research notesExplain the existence and the role of the symplectic nature of the groupoid/algebroid and its relevance for the geometry of the moduli spaces of geome...
Constant mean curvature in homogeneous $3$-manifolds — Question 2
v1.3 research notes; Calabi-Yau problem. For an embedded minimal surface in $\mathbb{R}^3$, does complete imply proper?; Hoffman-Meeks conjecture. For a complete embedde...
Minimax minimal surfaces
v1.3 research notesProve the lower bound \[ d\le \mbox{Index}(\Phi_{\mathcal A})+\mbox{Null}(\Phi_{\mathcal A}), \] where $\mbox{Null}(\Phi_{\mathcal A})$ is the {\it nu...
Minimax minimal surfaces — Question 2
v1.3 research notesProve that there exists infinitely many distinct minimal branched 2-dimensional immersions in $N^n$....
Closed geodesics
v1.3 research notesIs this true without the bumpy assumption?...
Configuration Spaces of Tensegrities — Problem 2
v1.3 research notesDescribe all the possible different types of strata for 10 points....
Configuration Spaces of Tensegrities — Problem 3
v1.3 research notesCompute the number of different types of strata for n points with arbitrary n. 4 OLEG KARPENKOV v1 v2 v3v4 v5 v6 K3;3 q1 q2 q3 p1 p2 p3 p4 p5 p6 q3 q2 ...
Configuration Spaces of Tensegrities — Problem 4
v1.3 research notesWhich subgraphs of Kn define the same stratifications?...
Configuration Spaces of Tensegrities — Problem 5
v1.3 research notesFind all strata of codimension more than 1 that are not defined as an intersection of the closure of several codimension 1 strata....
Configuration Spaces of Tensegrities — Problem 6
v1.3 research notesWhich Cayley algebra systems define the same strata?...
Configuration Spaces of Tensegrities — Problem 8
v1.3 research notesWrite (if exist) Cayley algebra systems defining the strata for the following graph: Currently this example is a strong candidate for a counterexample ...
Configuration Spaces of Tensegrities — Problem 9
v1.3 research notesDevelop theory of geometric conditions for strata in multidimensional case....
Geometry of Curves and Surfaces — Problem 1.1
v1.3 research notesDoes there exist a closed C2 surface in Euclidean space R3 which is flexible?...
Geometry of Curves and Surfaces — Problem 1.2
v1.3 research notesAre all smooth tight surfaces in R3 rigid?...
Geometry of Curves and Surfaces — Problem 1.3
v1.3 research notesAre negatively curved annuli bounded by a pair of fixed convex planar curves rigid?...
Geometry of Curves and Surfaces — Problem 1.5
v1.3 research notesGiven a metric of positive curvature on the disk what is the condition on a space curve to form the boundary of an isometric embedding of the disk?...
Geometry of Curves and Surfaces — Problem 1.7
v1.3 research notesAre there some nonconvex surfaces which remain rigid after finitely many points of them have been deleted. For instance, are punctured analytic tight s...
Geometry of Curves and Surfaces — Problem 1.8
v1.3 research notes(The global isometric embedding problem, Yau [189] 1993; Gromov [82]). Can everyC∞ 2-dimensional Riemannian manifold be isometrically embedded in R4?...
Geometry of Curves and Surfaces — Problem 2.1
v1.3 research notesFor which setsA⊂ Sn is there an immersionf: M→ Rn+1 such that Gf(M)⊂A?...
Geometry of Curves and Surfaces — Problem 2.3
v1.3 research notesLetM,M′⊂ R3 be smooth orientable closed surfaces. Suppose there exists a diffeomorphism f: M→ M′ which preserved the Gauss curvature and the Gauss map....
Geometry of Curves and Surfaces — Problem 2.4
v1.3 research notesLetP, P′⊂ R3 be polyhedral surfaces. Suppose that the faces of P and P′ are parallel and have the same area. Does it follow then that P and P′ are con...
Geometry of Curves and Surfaces — Problem 3.1
v1.3 research notesIs every convex polytope unfoldable?...
Geometry of Curves and Surfaces — Problem 3.2
v1.3 research notesDoes there exist a reasonably simple algorithm for detecting the edges of a convex polyhedron intrinsically?...
Geometry of Curves and Surfaces — Problem 3.3
v1.3 research notesDoes there exist a convex polyhedron with a pseudo edge graph which is not unfoldable....
Geometry of Curves and Surfaces — Problem 4.1
v1.3 research notesOf all convex surfaces with a fixed intrinsic diameter, is the one with the greatest area a doubled disk?...
Geometry of Curves and Surfaces — Problem 4.2
v1.3 research notesLet S ⊂ R3 be a closed surface of constant width and fixed area. How small can the volume of S be?...
Geometry of Curves and Surfaces — Problem 4.3
v1.3 research notesLetS⊂ R3 be a closed surface of diameter d. Suppose that there exists a constant h < dso that whenever a pair of planes separated by a distance of h i...
Geometry of Curves and Surfaces — Problem 5.2
v1.3 research notesLet $\Gamma$ be a closed curve of fixed length $L$ in $\mathbb{R}^3$. Determine the maximum possible volume of the convex hull of $\Gamma$....
Geometry of Curves and Surfaces — Problem 5.3
v1.3 research notesLet $\Gamma$ be a closed curve of fixed length $L$ in $\mathbb{R}^3$, and let $A$ be the area of its convex hull. Prove that $A$ is maximized when $\G...
Geometry of Curves and Surfaces — Problem 6.1
v1.3 research notesIs every compact connected minimal surface bounded by a pair of convex planar curves topologically an annulus?...
Geometry of Curves and Surfaces — Problem 7.2
v1.3 research notesAre there any complete negatively curved surfaces embedded in the unit ball?...
Geometry of Curves and Surfaces — Problem 7.3
v1.3 research notesDoes there exist any complete negatively curved surfaces with negative Euler characteristic contained in between a pair of parallel planes in R3....
Geometry of Curves and Surfaces — Problem 8.3
v1.3 research notesLet M be a complete noncompact convex surface in R3, with principal curvatures k1, k2, then show that inf M|k1−k2| = 0....
Bass conjecture
v1.3 research notesBass conjecture: for every finitely generated $\mathbb Z$-algebra $A$ and every $n\geq0$, is the G-theory group $K'_n(A)$ finitely generated? Equivale...
Fröberg conjecture on the Hilbert functions of a set of forms
v1.3 research notesFröberg conjecture on the Hilbert functions of a set of forms....
Wikipedia geometry item 7: Fujita conjecture regarding the line bundle $K_{M} \otimes L^{\otimes m}$ constructed from a po…
v1.3 research notesFujita conjecture regarding the line bundle $K_{M} \otimes L^{\otimes m}$ constructed from a positive holomorphic line bundle $L$ on a compact complex...
General elephant problem
v1.3 research notesGeneral elephant problem: do general elephants have at most Du Val singularities?...
Wikipedia geometry item 13: Nagata's conjecture on curves, specifically the minimal degree required for a plane algebraic c…
v1.3 research notesNagata's conjecture on curves, specifically the minimal degree required for a plane algebraic curve to pass through a collection of very general point...
Wikipedia geometry item 14: Nagata–Biran conjecture that if $X$ is a smooth algebraic surface and $L$ is an ample line bund…
v1.3 research notesNagata–Biran conjecture that if $X$ is a smooth algebraic surface and $L$ is an ample line bundle on $X$ of degree $d$, then for sufficiently large $r...
Nakai conjecture
v1.3 research notesNakai conjecture: if a complex algebraic variety has a ring of differential operators generated by its contained derivations, then it must be smooth....
Wikipedia geometry item 17: Section conjecture on splittings of group homomorphisms from fundamental groups of complete smo…
v1.3 research notesSection conjecture on splittings of group homomorphisms from fundamental groups of complete smooth curves over finitely-generated fields $k$ to the Ga...
Zariski multiplicity conjecture on the topological equisingularity and equimultiplicity of varieties at singular points
v1.3 research notesZariski multiplicity conjecture on the topological equisingularity and equimultiplicity of varieties at singular points...