Mathematics Problem Archive
Virtual-knot problem 41 — Which quantum invariants extend to virtual knots themselves without restrictions?
v1.3 research notesWhich quantum invariants extend to virtual knots themselves without restrictions? Certainly, there are such ones, e.g., the Kauffman bracket and the J...
Virtual-knot problem 42 — One can consider braids with even numbers of strands.
v1.3 research notesOne can consider braids with even numbers of strands. Markov's moves change the parity of the number of strands. Can one reformulate Markov's theorem ...
Virtual-knot problem 43 — In his wonderful paper , which firstly had the title “Knot Floer Homotopy”, Sarkar constructs a cell complex.
v1.3 research notesIn his wonderful paper , which firstly had the title “Knot Floer Homotopy”, Sarkar constructs a cell complex. The homology of this complex coincides w...
Virtual-knot problem 44 — A complete invariant is used for proving that one theory is a part of another theory.
v1.3 research notesA complete invariant is used for proving that one theory is a part of another theory. For example, the fact that the set of classical knots is a part ...
Virtual-knot problem 45 — To prove that the invariant $\mathcal{F}$ constructed by V.
v1.3 research notesTo prove that the invariant $\mathcal{F}$ constructed by V. O. Manturov for virtual braids, is complete for virtual braids with more than two strands....
Virtual-knot problem 46 — In it was showed how one could determine non-invertibility of long virtual knots and non-commutativity of long virtua…
v1.3 research notesIn it was showed how one could determine non-invertibility of long virtual knots and non-commutativity of long virtual knots. This method used two typ...
Virtual-knot problem 47 — It is well known that flat virtual knots are easily algorithmically recognizable, see .
v1.3 research notesIt is well known that flat virtual knots are easily algorithmically recognizable, see . The absence of a geometric approach to the definition of free ...
Virtual-knot problem 48 — The functorial mapping was constructed, by means of it we constructed the map from the set of virtual knots to the se…
v1.3 research notesThe functorial mapping was constructed, by means of it we constructed the map from the set of virtual knots to the set of virtual knots with orientabl...
Virtual-knot problem 49 — Turaev constructed the map from the set of long flat knots to the set of long virtual knots.
v1.3 research notesTuraev constructed the map from the set of long flat knots to the set of long virtual knots. Can one construct any map from the set of long free knots...
Virtual-knot problem 50 — The problem about cobordisms in sections: Let us have a free knot and its cobordism.
v1.3 research notesThe problem about cobordisms in sections: Let us have a free knot and its cobordism. Construct a parity on the given free knot, which is defined by us...
Virtual-knot problem 51 — Prove or disprove the conjecture about the non-uniqueness of minimal representative of a free link, i.e.
v1.3 research notesProve or disprove the conjecture about the non-uniqueness of minimal representative of a free link, i.e. there exists a free link having several minim...
Virtual-knot problem 52 — If $X$ is the free rack, is $\Gamma X$ a cat(0) space?
v1.3 research notesIf $X$ is the free rack, is $\Gamma X$ a cat(0) space? A positive answer would imply that all its higher homotopy groups are trivial....
Virtual-knot problem 53 — Is there any algorithm for recognition whether two graph-links are equivalent or not?
v1.3 research notesIs there any algorithm for recognition whether two graph-links are equivalent or not? Our conjecture is “no”. The idea behind that is that graph-links...
Virtual-knot problem 54 — Can one construct a projection from the set of graph-links to the set of realizable graph-links?
v1.3 research notesCan one construct a projection from the set of graph-links to the set of realizable graph-links?...
Virtual-knot problem 55 — Construct a parity on graph-links by using Bouchet's criterion about the realizability of a graph.
v1.3 research notesConstruct a parity on graph-links by using Bouchet's criterion about the realizability of a graph. Try to find a parity which is responsible for the c...
Virtual-knot problem 56 — Construct generalizations of the Frobenius extension and the Rasmussen for “rigid” graph-links with orientable atoms.
v1.3 research notesConstruct generalizations of the Frobenius extension and the Rasmussen for “rigid” graph-links with orientable atoms....
Virtual-knot problem 57 — Is it true that two equivalent realizable graph-links are equivalent in the class of realizable graph-links?
v1.3 research notesIs it true that two equivalent realizable graph-links are equivalent in the class of realizable graph-links? If it is not true, then construct an exam...
Virtual-knot problem 58 — Construct a group for graph-links which is analogous to the group from .
v1.3 research notesConstruct a group for graph-links which is analogous to the group from ....
Virtual-knot problem 59 — Construct “graph-braids”.
v1.3 research notesConstruct “graph-braids”....
Virtual-knot problem 60 — Problems on Free Knot Cobordism
v1.3 research notesProblems on Free Knot Cobordism: The methods used for proving the fact that the invariant $L$ gives an obstruction to the sliceness are not immediatel...
String topology and smooth structures on 4-manifolds
v1.3 research notesIs string topology sensitive to smooth structures on 4-manifolds?...
Problem 1A — Present explicit obstructions to the Lyashko–Looijenga covering in terms of braid groups.
v1.3 research notesPresent explicit obstructions to the Lyashko–Looijenga covering in terms of braid groups. Which braids cannot be lifted to the space ${\mathbb{C}}^{\m...
Problem 1B — Let a non-simple singularity $f$ be given and the Dynkin diagram of it be defined by an easily disting…
v1.3 research notesLet a non-simple singularity $f$ be given and the Dynkin diagram of it be defined by an easily distinguished system of paths connecting 0 with critica...
Problem 1C — Are there more refined restrictions to the collision of critical values?
v1.3 research notesAre there more refined restrictions to the collision of critical values? Is it true that for any two vanishing cycles, whose intersection number is eq...
Problem 1D — Give more general lower bounds of the dimension of $\mu=const$ strata in terms of intersection forms o…
v1.3 research notesGive more general lower bounds of the dimension of $\mu=const$ strata in terms of intersection forms of vanishing cycles....
Problem 1E — What are the obstructions to the realization of these chains of formal changes by paths in the paramet…
v1.3 research notesWhat are the obstructions to the realization of these chains of formal changes by paths in the parameter space ${\mathbb{R}}^{k}$?...
Problem 1F — Is there any convenient topological characteristic of the function $f_{-\varepsilon}$ which allows to…
v1.3 research notesIs there any convenient topological characteristic of the function $f_{-\varepsilon}$ which allows to predict these indices?...
Problem 2A — What is the minimal number of open sets $U_{i}$ covering ${\mathbb{R}}^{6}$ such that for any $U_{i}$…
v1.3 research notesWhat is the minimal number of open sets $U_{i}$ covering ${\mathbb{R}}^{6}$ such that for any $U_{i}$ there is a continuous map $\varphi_{i}:U_{i}\to{...
Problem 2B — The same questions concerning the approximate solutions.
v1.3 research notesThe same questions concerning the approximate solutions. That is, for any $i$ and any $(a,b)\in U_{i}$, the value $\varphi_{i}(a,b)$ should be not nec...
Problem 3 — Is the complement of the essential ramification set in ${\mathbb{R}}^{d}$ a $K(\pi,1)$-space?
v1.3 research notesIs the complement of the essential ramification set in ${\mathbb{R}}^{d}$ a $K(\pi,1)$-space?...
Problem 4 — Are these geometric obstructions sufficient to solve the above problem?
v1.3 research notesAre these geometric obstructions sufficient to solve the above problem?...
Problem 5A — Is it true that any hypersurface from the space $P(d;N)$ can be connected with a trivial one by a gene…
v1.3 research notesIs it true that any hypersurface from the space $P(d;N)$ can be connected with a trivial one by a generic path in this space in such a way that it exp...
Problem 5B — A version of the previous problem, in which the complexity measure is not purely topological: namely,…
v1.3 research notesA version of the previous problem, in which the complexity measure is not purely topological: namely, it is the lowest number of critical points of Mo...
Problem 5C — Give an upper bound for the function $T\mapsto F$.
v1.3 research notesGive an upper bound for the function $T\mapsto F$....
Problem 5D — Do non-singular real plane projective curves of an odd degree consisting of a single connected compone…
v1.3 research notesDo non-singular real plane projective curves of an odd degree consisting of a single connected component form a connected set (i.e., are they rigid is...
Problem 6A — Is it true that any real Morsification of $f$ can be connected with one of complexity $\rho(f)$ by a g…
v1.3 research notesIs it true that any real Morsification of $f$ can be connected with one of complexity $\rho(f)$ by a generic path in the base of a versal deformation,...
Problem 6B — What can be said about the number $\rho(f)$?
v1.3 research notesWhat can be said about the number $\rho(f)$?...
Problem 6C — Is it true that any component of the complement of the discriminant variety of a versal deformation co…
v1.3 research notesIs it true that any component of the complement of the discriminant variety of a versal deformation contains a Morsification, whose all $\mu(f)$ criti...
Problem 7 — Give a similar universal estimate of the radius of convergence for multidimensional Newton’s method of…
v1.3 research notesGive a similar universal estimate of the radius of convergence for multidimensional Newton’s method of [Shub and Smale1993]....
1.1 (Agol) — Strictly convex projective manifolds and cubulation
v1.3 research notesIf $M^n$ is a closed manifold with a strictly convex projective structure, is it cubulated?...
1.2 (Choi) — Convex projective deformations from a CR structure
v1.3 research notesSuppose a hyperbolic $3$-manifold $M$ admits a CR structure, not necessarily a spherical one. Can the deformation theory of convex real projective str...
1.3 (Cooper) — Convexity of projective structures on hyperbolic 3-manifolds
v1.3 research notesIf $M$ is a closed hyperbolic $3$-manifold, is every projective structure on $M$ convex?...
1.4 (Danciger) — Convex projective structures on glued figure-eight complements
v1.3 research notesLet $N$ be the closed $3$-manifold obtained by gluing two copies of the figure-eight knot complement along their torus boundaries by a homeomorphism. ...
1.5 (Danciger) — Convex projective structures and hyperbolic JSJ pieces
v1.3 research notesLet $N$ be a closed $3$-manifold whose JSJ decomposition contains only hyperbolic pieces. Does $N$ admit a convex projective structure?...
2.1 (Leitner) — Limits between Thurston geometries
v1.3 research notesGeometric transitions are continuous paths of geometries that abruptly change type in the limit. Understand all transitions between the eight Thurston...
2.2 (Cooper) — An invariant polynomial on a tensor product
v1.3 research notesDoes there exist a nonzero polynomial on $U\otimes V\otimes W$ invariant under $SL(U)\times SL(V)\times SL(W)$ when $\dim U=\dim V=4$ and $\dim W=8$?...
2.3 (Cooper) — Hausdorff limits of conjugates of an isometry group
v1.3 research notesLet $\beta$ be a nondegenerate bilinear form on a finite-dimensional real vector space $V$, and let $G=\operatorname{Isom}(\beta)\subset GL(V)$. Which...
3.2 (Agol) — A minimal-Thurston-norm surface from a tree action
v1.3 research notesLet $M$ be a $3$-manifold whose fundamental group acts on a simplicial tree without global fixed points. In the covering space associated to an edge s...
3.3 (Agol) — Injective surfaces with only double curves
v1.3 research notesDoes every closed hyperbolic $3$-manifold contain a closed $\pi_1$-injective surface with only double curves of intersection?...
3.4 (Agol) — Injective surfaces with the 1-line property
v1.3 research notesDoes every closed hyperbolic $3$-manifold contain a closed $\pi_1$-injective surface with the 1-line property: in the universal cover, every pair of p...