Mathematics Problem Archive

Showing 101-150 of 179 problems (Page 3 of 4)

AMR-066-0080
Partially Solved

Scalar Curvature Question [?82]: C0-ContinuousGuth-GerochLowerVolume Bound for Balls in the Coverings of Essential Manifolds

v1.3 research notes

Conjecture. C0-ContinuousGuth-GerochLowerVolume Bound for Balls in the Coverings of Essential Manifolds. [57]. The universal coverings ˜X of Q-essenti...

L4
Geometry
AMR-066-0083
Partially Solved

Scalar Curvature Question [?85]: C0-Density of C0-metrics with Volumically Positive Scalar Curvatures

v1.3 research notes

Conjecture. C0-Density of C0-metrics with Volumically Positive Scalar Curvatures. Continuous Riemannian metrics withScvoln > 0 on anX are dense in the...

L4
Geometry
AMR-066-0085
Partially Solved

Scalar Curvature Question [?87]: but there are no apparent examples (if any) where these inequalities are strict

v1.3 research notes

but there are no apparent examples (if any) where these inequalities are strict. Everything we know aboutK-area+ easily extends to the the FredholmKar...

L4
Geometry
AMR-066-0086
Partially Solved

Scalar Curvature Question [?90]: Hyperbolic Volume Inequality

v1.3 research notes

Conjecture. Hyperbolic Volume Inequality.Then every continuous mapf0∶X→X0 is homotopic to a mapf, such that voln(f(X)) ≤vol(X) where, moreover, this i...

L4
Geometry
AMR-066-0087
Partially Solved

Scalar Curvature Question [?91]: Prove that there is a dimension-dependent constant $c_n$ such that every compact Riemannian $n$-manifold $X$ w

v1.3 research notes

Prove that there is a dimension-dependent constant $c_n$ such that every compact Riemannian $n$-manifold $X$ with $\operatorname{Sc}(X)\geq-\sigma^2$ ...

L4
Geometry
AMR-068-0007
Partially Solved

Configuration Spaces of Tensegrities — Problem 7

v1.3 research notes

Given a graph G. Does there exist a Cayley algebra system (or several systems) describing the union of the codimension 1 tensegrity strata in the plan...

L4
Geometry
AMR-069-0024
Partially Solved

Geometry of Curves and Surfaces — Problem 6.2

v1.3 research notes

Does there exist an embedded compact surface of constant mean curvature which is bounded by a circle, but is not a piece of a sphere....

L4
Geometry
AMR-069-0025
Partially Solved

Geometry of Curves and Surfaces — Problem 6.3

v1.3 research notes

Show that any compact embedded CMC surface which is bounded by a convex planar curve, and lies on one side of the boundary plane, is topologically a d...

L4
Geometry
AMR-069-0029
Partially Solved

Geometry of Curves and Surfaces — Problem 8.2

v1.3 research notes

Show that the index of any singularity of a principal line fields on a surface is at most one....

L4
Geometry
AMR-071-0056
Partially Solved

Finding matching upper and lower bounds for k-sets and halving lines

v1.3 research notes

Finding matching upper and lower bounds for k-sets and halving lines...

L4
Geometry
AMR-074-0003
Partially Solved

Automorphism Problem for the Turing Degrees

v1.3 research notes

Determine the automorphism group of the partial order of Turing degrees....

L4
Logic
AMR-075-0005
Partially Solved

The main gap conjecture, e.g. for uncountable first order theories, for AECs, and for $\aleph_1$-saturated models of a countable theory

v1.3 research notes

The main gap conjecture, e.g. for uncountable first order theories, for AECs, and for $\aleph_1$-saturated models of a countable theory....

L4
Logic
AMR-075-0006
Partially Solved

Shelah's categoricity conjecture for $L_{\omega_1,\omega}$

v1.3 research notes

Shelah's categoricity conjecture for $L_{\omega_1,\omega}$: If a sentence is categorical above the Hanf number then it is categorical in all cardinals...

L4
Logic
AMR-075-0007
Partially Solved

Shelah's eventual categoricity conjecture

v1.3 research notes

Shelah's eventual categoricity conjecture: For every cardinal $\lambda$ there exists a cardinal $\mu(\lambda)$ such that if an AEC K with LS(K)${} \le...

L4
Logic
AMR-075-0009
Partially Solved

Does every simple first-order theory have stable forking

v1.3 research notes

Does every simple first-order theory have stable forking?...

L4
Logic
AMR-075-0011
Partially Solved

The universality problem for C-free graphs

v1.3 research notes

The universality problem for C-free graphs: For which finite sets C of graphs does the class of C-free countable graphs have a universal member under ...

L4
Logic
AMR-075-0014
Partially Solved

Wikipedia model theory and formal languages item 14: Assume K is the class of models of a countable first order theory omitting countably many types…

v1.3 research notes

Assume K is the class of models of a countable first order theory omitting countably many types. If K has a model of cardinality $\aleph_{\omega_1}$ d...

L4
Logic
AMR-075-0018
Partially Solved

If the class of atomic models of a complete first order theory is categorical in the $\aleph_n$, is it categorical in every cardinal

v1.3 research notes

If the class of atomic models of a complete first order theory is categorical in the $\aleph_n$, is it categorical in every cardinal?...

L4
Logic
AMR-075-0020
Partially Solved

Is the Borel monadic theory of the real order (BMTO) decidable? Is the monadic theory of well-ordering (MTWO) consistently decidable

v1.3 research notes

Is the Borel monadic theory of the real order (BMTO) decidable? Is the monadic theory of well-ordering (MTWO) consistently decidable?...

L4
Logic
AMR-077-0009
Partially Solved

Separatrix Splitting under Quasiperiodic Forcing

v1.3 research notes

Find an asymptotic expression for the splitting of the separatrix of a quasiperiodically forced pendulum in the regime where the perturbation series i...

L4
Mathematical Physics
AMR-079-0006
Partially Solved

$\beta$-ensembles

v1.3 research notes

Random point processes corresponding to $\beta$-ensembles, or, equivalently, log gases at inverse temperature $\beta$, are defined for arbitrary $\bet...

L4
Mathematical Physics
AMR-080-0001
Partially Solved

KdV with almost periodic initial data

v1.3 research notes

Consider the Korteweg--de Vries (KdV) equation u_t + u u_x + u_{xxx} =0 with initial data u(x, t=0) = u_0(x),\qquad x\in \mathbb{R}. In the 1970's, Mc...

L4
Mathematical Physics
AMR-080-0003
Partially Solved

interacting particle systems and KPZ

v1.3 research notes

In 1999, J. All these early examples were ``integrable'' in the sense that certain powerful algebraic tools, e.g., determinantal particle systems, the...

L4
Mathematical Physics
AMR-080-0005
Partially Solved

initial boundary value problems for integrable systems (IBVP)

v1.3 research notes

Initial boundary value problems for integrable systems in $1+1$ dimensions are of great interest. It turns out, however, that in Fokas' approach the g...

L4
Mathematical Physics
AMR-080-0006
Partially Solved

numerical solution of integrable systems

v1.3 research notes

Solutions of the Cauchy problem for linear dispersive equations can be expressed in terms of Fourier integral operators. This is a very challenging pr...

L4
Mathematical Physics
AMR-084-0007
Partially Solved

Existence of a rational Diophantine septuple

v1.3 research notes

Does there exist a rational Diophantine septuple, that is, seven nonzero rational numbers whose pairwise products plus $1$ are rational squares?...

L4
Graph Theory
AMR-084-0008
Partially Solved

Parameters admitting infinitely many rational D(q)-quintuples

v1.3 research notes

For which rational numbers $q$ do there exist infinitely many rational $D(q)$-quintuples?...

L4
Graph Theory
AMR-086-0002
Partially Solved

Conjecture 1.3 — Pillai

v1.3 research notes

Let $k$ be a positive integer. The equation $$ x^p-y^q=k, $$ where the unknowns $x$, $y$, $p$ and $q$ take integer values, all $\ge 2$, has only finit...

L4
Graph Theory
AMR-086-0010
Partially Solved

Conjecture 2.2 — Erdős-Woods

v1.3 research notes

There exists a positive integer $k$ such that, for $m$ and $n$ positive integers, the conditions $$ R(m+i)=R(n+i)\quad (i=0,\ldots,k-1) $$ imply $m=n$...

L4
Graph Theory
AMR-086-0018
Partially Solved

Conjecture 2.15 — Mahler

v1.3 research notes

Let $(\varepsilon_n)_{n\ge 0}$ be a sequence of elements in $\{0,1\}$. Assume that the real number $$ \sum_{n\ge 0}\varepsilon_n 3^{-n} $$ is irration...

L4
Graph Theory
AMR-086-0033
Partially Solved

Conjecture 3.15 — Goncharov

v1.3 research notes

As a $\mathbb{Q}$-algebra, $\mathfrak{Z}$ is the direct sum of $\mathfrak{Z}_p$ for $p\ge 0$....

L4
Graph Theory
AMR-086-0034
Partially Solved

Conjecture 3.16 — Zagier

v1.3 research notes

For $p\ge 3$ we have $$ d_p=d_{p-2}+d_{p-3} $$ with $d_0=1$, $d_1=0$, $d_2=1$....

L4
Graph Theory
AMR-086-0037
Partially Solved

Conjecture 3.19 — Rohrlich

v1.3 research notes

$\overline{G}$ is a universal odd distribution with values in groups where multiplication by $2$ is invertible....

L4
Graph Theory
AMR-086-0053
Partially Solved

Conjecture 4.11 — Wirsing and Schmidt

v1.3 research notes

For any positive integer $n$ and any real number $\theta$ which is either transcendental or else is algebraic of degree $>n$, there exists a positive ...

L4
Graph Theory
AMR-086-0059
Partially Solved

Question 4.17 — Mazur

v1.3 research notes

Assume that $K=\mathbb{Q}$ and that $V(\mathbb{Q})$ is Zariski dense; is $Z$ a union of connected components of $V(\mathbb{R})$?...

L4
Graph Theory
AMR-086-0061
Partially Solved

Conjecture 4.19

v1.3 research notes

Let $A$ be a simple Abelian variety of dimension $g$ over a number field $K$ embedded in $\mathbb{R}$. Denote by $\ell$ the rank over $\mathbb{Z}$ of ...

L4
Graph Theory
AMR-093-0104
Partially Solved

Wikipedia number-theory item 104: Congruent number problem (a corollary to Birch and Swinnerton-Dyer conjecture, per Tunnell's theorem…

v1.3 research notes

Congruent number problem (a corollary to Birch and Swinnerton-Dyer conjecture, per Tunnell's theorem): determine precisely what rational numbers are c...

L4
Number Theory
AMR-094-0001
Partially Solved

Probabilistic McMillan theorem in higher dimensions

v1.3 research notes

Let $X_t$ be $d$-dimensional Brownian motion starting at the origin, let $D$ be an open subset of $\mathbb{R}^d$ containing the origin, and let $\tau=...

L4
Probability
AMR-094-0007
Partially Solved

Are shy couplings necessarily rigid?

v1.3 research notes

Let $D\subset\mathbb{R}^d$, $d\ge2$, be bounded, connected, and open. Suppose there are coupled reflected Brownian motions $X_t,Y_t$ in $D$ and $\vare...

L4
Probability
AMR-095-0001
Partially Solved

Stationary distributions in one dimension

v1.3 research notes

For the exclusion process on $\mathbb{Z}$ with $p(x,y)=p(y-x)$, assume $\sum_x|x|p(x)<\infty$, $\sum_xxp(x)>0$, and $\sum_{x<0}x^2p(x)=\infty$. Does t...

L4
Probability
AMR-095-0003
Partially Solved

Exchangeability in the mean-zero exclusion process

v1.3 research notes

For the exclusion process on $\mathbb{Z}^d$ with translation-invariant kernel $p(x,y)=p(y-x)$ and zero mean $\sum_xxp(x)=0$, prove that every stationa...

L4
Probability
AMR-095-0004
Partially Solved

Negative association for asymmetric exclusion

v1.3 research notes

For nearest-neighbor asymmetric exclusion on $\mathbb{Z}$ with $p(1)=p>q=p(-1)$, start from the deterministic configuration $\cdots11110000\cdots$. Is...

L4
Probability
AMR-096-0037
Partially Solved

Topology and geometry of a self-similar random planar partition

v1.3 research notes

For Aldous's self-similar random partition of the plane, determine its topological properties: in particular, do region boundaries have fractal dimens...

L4
Probability
AMR-098-0008
Partially Solved

Mass-stationarity of diffuse random measures via allocations

v1.3 research notes

Let $(X,\xi)$ consist of a random element and a diffuse random measure on a locally compact second countable Abelian group. Is mass-stationarity of $(...

L4
Probability
AMR-098-0009
Partially Solved

Markovian-kernel characterization of mass-stationarity

v1.3 research notes

Does the invariant-transport characterization of mass-stationarity remain valid if the bounded jointly invariant preserving kernels are restricted to ...

L4
Probability
AMR-099-0038
Partially Solved

Cheeger constant and the percolation nonuniqueness phase

v1.3 research notes

For every infinite vertex-transitive graph $G$, prove that $p_c(G)<p_u(G)$ if and only if $h(G)>0$....

L4
Probability
AMR-099-0086
Partially Solved

When is the uniqueness threshold below one?

v1.3 research notes

Give general conditions implying $p_u(G)<1$. In particular, prove or disprove that every one-ended transitive graph has $p_u(G)<1$....

L4
Probability
AMR-100-0001
Partially Solved

No percolation at the critical point on $\mathbb{Z}^d$

v1.3 research notes

For nearest-neighbor independent bond percolation on $\mathbb{Z}^d$, $d\ge2$, let $p_c(d)$ be the critical edge-retention probability. Prove that at $...

L4
Probability
AMR-105-0053
Partially Solved

Virtual-knot problem 53 — Is there any algorithm for recognition whether two graph-links are equivalent or not?

v1.3 research notes

Is 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...

L4
Topology
AMR-109-0005
Partially Solved

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 notes

What 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...

L4
Topology