5.16 (Walsh) — Hyperbolic groups with Kleinian-type boundaries
v1.3 research notesIf $G$ is a Gromov-hyperbolic group whose boundary is homeomorphic to the limit set of a convex-cocompact Kleinian group, is $G$ virtually a convex-co...
5.18 (Walsh) — Sierpiński carpets and continua in Kleinian limit sets
v1.3 research notesFor which Kleinian groups does the limit set contain a Sierpiński carpet? For which Kleinian groups does the limit set contain a continuum?...
6.1 (I. Kapovitch) — Random walks and generic pseudo-Anosov singularities
v1.3 research notesShow that a random walk on the mapping class group gives a pseudo-Anosov element whose invariant foliations have generic trivalent singularities with ...
6.4 (Maher) — Generic mapping-class orbit points in Teichmüller balls
v1.3 research notesFor the orbit of a point $x$ in Teichmüller space under the mapping class group, show that as $r\to\infty$: (1) the proportion of orbit points in the ...
7.3 (Manning) — Number fields as trace fields
v1.3 research notesIf $k$ is a number field that is not totally real, is there a hyperbolic $3$-manifold with trace field $k$?...
8.2 (Dunfield) — Profinite detection of knot complements
v1.3 research notesFor a hyperbolic $3$-manifold with torus boundary, does its profinite completion determine whether it is a knot complement?...
8.4 (Schleimer) — Detecting reducible Heegaard splittings
v1.3 research notesIs there an algorithm to detect whether a Heegaard splitting is reducible and, if so, find a reducing curve?...
8.5 (Schleimer) — Classification of strongly irreducible Heegaard splittings
v1.3 research notesIs there a classification of the strongly irreducible Heegaard splittings of a given $3$-manifold?...
8.7 (Tillmann) — Higher-dimensional multisections and stabilization
v1.3 research notesDo higher-dimensional smooth manifolds always admit multisections? What is the correct generalization of uniqueness up to stabilization for multisecti...
Problem 2.1 — Determine the finiteness properties of Ig.
v1.3 research notesDetermine the finiteness properties of Ig. For which k is Hk(Ig) finitely gen- erated? For which k is there a K(Ig, 1) with finite k-skeleton (one say...
Problem 3.1 — What is the smallest n = n(g) such that MCG (Sg) admits a properly dis- continuous action on Rn?
v1.3 research notesWhat is the smallest n = n(g) such that MCG (Sg) admits a properly dis- continuous action on Rn? on a contractible n-manifold? (The answers are expect...
Question 2.9 — Is it true that, given any pseudo-Anosov φ∈ Modg, there exists n =n(φ) such that the normal closure of φn is free?
v1.3 research notesIs it true that, given any pseudo-Anosov φ∈ Modg, there exists n =n(φ) such that the normal closure of φn is free? Gromov discovered the analogous phe...
Question 3.1 — (Fast word problem).
v1.3 research notes(Fast word problem). Is there a sub-quadratic time algorithm to solve the word problem in Modg? One might guess that n logn is possible here, as there...
Conjecture 3.15 — (Density of pseudo-Anosovs).
v1.3 research notes(Density of pseudo-Anosovs). LetP denote the set of pseudo-Anosov ele- ments of Modg. Then d(P) = 1. J. Maher [ Mah] has recently proven that a random...
Problem 3.1 — Study, systematically and with the help of computers, the finite quotients of Mg which do not factor through Sp (2g, Z).
v1.3 research notesStudy, systematically and with the help of computers, the finite quotients of Mg which do not factor through Sp (2g, Z). We remark that Problem 3.1 wo...
Problem 3.2 — Construct any representations of Mg, finite or infinite, which do not factor through Sp(2g, Z).
v1.3 research notesConstruct any representations of Mg, finite or infinite, which do not factor through Sp(2g, Z). In a very different direction, every mathematician woul...
Problem 3.3 — Is there a faithful finite dimensional matrix representation of Mg,b,n for any value of the triplet (g,b,n ) other th…
v1.3 research notesIs there a faithful finite dimensional matrix representation of Mg,b,n for any value of the triplet (g,b,n ) other than (1, 0, 0), (1, 1, 0), (1, 0, 1...
Problem 3.4 — Find a candidate for a faithful finite-dimensional matrix representation of Mg orMg,1,0.
v1.3 research notesFind a candidate for a faithful finite-dimensional matrix representation of Mg orMg,1,0....
Problem 1: — Determine the metric completion of the Gromov boundary of C(S) and relate this metric completion to the geometry of C…
v1.3 research notesDetermine the metric completion of the Gromov boundary of C(S) and relate this metric completion to the geometry of C(S). There is yet another way to ...
Problem 7: — Is the mapping class group linear?
v1.3 research notesIs the mapping class group linear? A locally compact group Γ is said to satisfy the Haagerup approximation property or is a-T- menable if there exists...
Major problems 3 — Find some geometric meaning for elliptic cohomology.
v1.3 research notesFind some geometric meaning for elliptic cohomology. I believe this problem may be solvable--we keep learning new things about it. One thing I will sa...
Major problems 4 — On the same theme, find some way of doing index theory related to elliptic cohomology.
v1.3 research notesOn the same theme, find some way of doing index theory related to elliptic cohomology. This is not really algebraic topology, but would have a major i...
Major problems 5 — The chromatic splitting conjecture, which is considerably more complicated to state.
v1.3 research notesThe chromatic splitting conjecture, which is considerably more complicated to state. Basically nothing is known about this, and so this one may be mor...
Major problems 8 — Say something general about the stable or unstable homotopy groups of spheres.
v1.3 research notesSay something general about the stable or unstable homotopy groups of spheres. For example, Ravenel has suggested that the size of the nth homotopy gr...
Major problems 10 — Once again, I am not sure whether this problem deserves to be called major, but it is annoying that th…
v1.3 research notesOnce again, I am not sure whether this problem deserves to be called major, but it is annoying that the the R. Cohen - Goerss result proving that h_0 ...
Morava K- and E-theory 1 — Show that pi_* L_K(n) S^0 is finitely generated over the p-adics in each degree.
v1.3 research notesShow that pi_* L_K(n) S^0 is finitely generated over the p-adics in each degree. This would follow from the chromatic splitting conjecture, I think. (...
Morava K- and E-theory 2 — Show that the Picard group is finitely generated over the p-adics.
v1.3 research notesShow that the Picard group is finitely generated over the p-adics. I don't think this is known even for the algebraic Picard group, which is obtained ...
Morava K- and E-theory 4 — As a rule, I am not happy about the arbitrary nature of some of the constructions in the K(n)-local ca…
v1.3 research notesAs a rule, I am not happy about the arbitrary nature of some of the constructions in the K(n)-local category. Consider the spectral sequence, for exam...
Morava K- and E-theory 5 — Find the shadow of the thick subcategory theorem in the K(n)-local category.
v1.3 research notesFind the shadow of the thick subcategory theorem in the K(n)-local category. There is only one thick subcategory of small spectra in the K(n)-local ca...
Morava K- and E-theory 8 — Understand the relationship between the K(n)-local category and some sort of (algebraic) derived categ…
v1.3 research notesUnderstand the relationship between the K(n)-local category and some sort of (algebraic) derived category of E_*-S-modules. Jens Franke has claimed th...
Morava K- and E-theory 9 — One of the corollaries of the Hopkins-Miller theorem, together with the Devinatz-Hopkins fixed point b…
v1.3 research notesOne of the corollaries of the Hopkins-Miller theorem, together with the Devinatz-Hopkins fixed point business, is that the famous class zeta in contin...
Morava K- and E-theory 10 — Bousfield has give a description of the E(1)-local category in terms of algebraic data related to K-th…
v1.3 research notesBousfield has give a description of the E(1)-local category in terms of algebraic data related to K-theory. Franke claims to have generalized all this...
Elliptic cohomology 2 — Almost everyone who has ever thought about elliptic cohomology ends up thinking it has something to do…
v1.3 research notesAlmost everyone who has ever thought about elliptic cohomology ends up thinking it has something to do with 2-categories. If you think about vector bu...
Elliptic cohomology 3 — Dennis McLaughlin and Jean-Luc Brylinski also thought along these lines.
v1.3 research notesDennis McLaughlin and Jean-Luc Brylinski also thought along these lines. They wanted to use gerbes, or 2-gerbes maybe, instead. I could never understa...
Elliptic cohomology 4 — Yet another idea is to go back to a decription of cobordism I once heard.
v1.3 research notesYet another idea is to go back to a decription of cobordism I once heard. I think this description is in print somewhere, but I don't know where or wh...
Applications 1 — Introduce stable homotopy theory into the world of C^*-algebras, like Voevodsky has done in algebraic…
v1.3 research notesIntroduce stable homotopy theory into the world of C^*-algebras, like Voevodsky has done in algebraic geometry. More specifically, find a model struct...
Applications 3 — Investigate Voevodsky's stable homotopy category of schemes from a homotopy theorist's point of view.
v1.3 research notesInvestigate Voevodsky's stable homotopy category of schemes from a homotopy theorist's point of view. This is obviously a huge, unstructured problem, ...
Applications 4 — Stefan Stolz showed that a simply connected Spin manifold of dimension at least 5 admits a metric of p…
v1.3 research notesStefan Stolz showed that a simply connected Spin manifold of dimension at least 5 admits a metric of positive scalar curvature if and only if its imag...
Applications 5 — Try to carry out Stolz's plan for metrics of positive Ricci curvature.
v1.3 research notesTry to carry out Stolz's plan for metrics of positive Ricci curvature. Here we expect the obstruction to lie in elliptic cohomology rather than K-theo...
Applications 8 — Extend the results of Benson-Carlson-Rickard to connected, cocommutative Hopf algebras over a field, l…
v1.3 research notesExtend the results of Benson-Carlson-Rickard to connected, cocommutative Hopf algebras over a field, like A(n). Hovey-Palmieri have achieved some part...
Axiomatic stable homotopy 1 — In our memoir, we give a conjecture for the thick subcategories in a Noetherian stable homotopy catego…
v1.3 research notesIn our memoir, we give a conjecture for the thick subcategories in a Noetherian stable homotopy category C--they should be in 1-1 correpondence with s...
Axiomatic stable homotopy 2 — Characterize the stable homotopy category up to equivalence.
v1.3 research notesCharacterize the stable homotopy category up to equivalence. This has been done for categories that are homotopy categories of model categories by Sch...
Axiomatic stable homotopy 4 — In one of Bob Thomason's last papers, he determined the thick subcategories of finite objects in the d…
v1.3 research notesIn one of Bob Thomason's last papers, he determined the thick subcategories of finite objects in the derived category of a scheme. For the derived cat...
Axiomatic stable homotopy 5 — John Palmieri has determined the E_2 term of the Adams spectral sequence up to nilpotence--at least he…
v1.3 research notesJohn Palmieri has determined the E_2 term of the Adams spectral sequence up to nilpotence--at least he has found a computable ring which is f-isomorph...
Axiomatic stable homotopy 6 — My general feeling about stable homotopy categories is that they are like commutative rings.
v1.3 research notesMy general feeling about stable homotopy categories is that they are like commutative rings. Follow this up; define Spec C for example, for a stable h...
Axiomatic stable homotopy 7 — The equivariant stable homotopy category is not treated very well in our memoir.
v1.3 research notesThe equivariant stable homotopy category is not treated very well in our memoir. That is, we assume that the generators have to be dualizable. This is...
Axiomatic stable homotopy 8 — From an axiomatic point of view, I don't understand Grojnowski's equivariant elliptic cohomology.
v1.3 research notesFrom an axiomatic point of view, I don't understand Grojnowski's equivariant elliptic cohomology. This theory takes values in an abelian category that...
Axiomatic stable homotopy 9 — Suppose G is a self-equivalence of the stable homotopy category.
v1.3 research notesSuppose G is a self-equivalence of the stable homotopy category. Must G be some iterate of the suspension functor? If G commutes with the suspension, ...
Equivariant homotopy 3 — Figure out how to do equivariant stable homotopy theory without restriction on the group.
v1.3 research notesFigure out how to do equivariant stable homotopy theory without restriction on the group. Here you are going to have to change the current setup a lot...
Equivariant homotopy 4 — As a simpler model of the equivariant stable homotopy category, construct a derived category of Mackey…
v1.3 research notesAs a simpler model of the equivariant stable homotopy category, construct a derived category of Mackey functors over a Green functor, and analyze its ...