Mathematics Problem Archive

Showing 1551-1600 of 2509 problems (Page 32 of 51)

AMR-067-0025
Open

Minimax minimal surfaces — Question 2

v1.3 research notes

Prove that there exists infinitely many distinct minimal branched 2-dimensional immersions in $N^n$....

L3
Geometry
AMR-067-0028
Open

Closed geodesics

v1.3 research notes

Is this true without the bumpy assumption?...

L3
Geometry
AMR-068-0002
Open

Configuration Spaces of Tensegrities — Problem 2

v1.3 research notes

Describe all the possible different types of strata for 10 points....

L3
Geometry
AMR-068-0003
Open

Configuration Spaces of Tensegrities — Problem 3

v1.3 research notes

Compute 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 ...

L3
Geometry
AMR-068-0004
Open

Configuration Spaces of Tensegrities — Problem 4

v1.3 research notes

Which subgraphs of Kn define the same stratifications?...

L3
Geometry
AMR-068-0005
Open

Configuration Spaces of Tensegrities — Problem 5

v1.3 research notes

Find all strata of codimension more than 1 that are not defined as an intersection of the closure of several codimension 1 strata....

L3
Geometry
AMR-068-0006
Open

Configuration Spaces of Tensegrities — Problem 6

v1.3 research notes

Which Cayley algebra systems define the same strata?...

L3
Geometry
AMR-069-0003
Open

Geometry of Curves and Surfaces — Problem 1.3

v1.3 research notes

Are negatively curved annuli bounded by a pair of fixed convex planar curves rigid?...

L3
Geometry
AMR-069-0013
Open

Geometry of Curves and Surfaces — Problem 2.4

v1.3 research notes

LetP, 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...

L3
Geometry
AMR-069-0014
Open

Geometry of Curves and Surfaces — Problem 3.1

v1.3 research notes

Is every convex polytope unfoldable?...

L3
Geometry
AMR-069-0015
Open

Geometry of Curves and Surfaces — Problem 3.2

v1.3 research notes

Does there exist a reasonably simple algorithm for detecting the edges of a convex polyhedron intrinsically?...

L3
Geometry
AMR-069-0017
Open

Geometry of Curves and Surfaces — Problem 4.1

v1.3 research notes

Of all convex surfaces with a fixed intrinsic diameter, is the one with the greatest area a doubled disk?...

L3
Geometry
AMR-069-0018
Open

Geometry of Curves and Surfaces — Problem 4.2

v1.3 research notes

Let S ⊂ R3 be a closed surface of constant width and fixed area. How small can the volume of S be?...

L3
Geometry
AMR-069-0019
Open

Geometry of Curves and Surfaces — Problem 4.3

v1.3 research notes

LetS⊂ 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...

L3
Geometry
AMR-069-0022
Open

Geometry of Curves and Surfaces — Problem 5.3

v1.3 research notes

Let $\Gamma$ 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...

L3
Geometry
AMR-069-0030
Open

Geometry of Curves and Surfaces — Problem 8.3

v1.3 research notes

Let M be a complete noncompact convex surface in R3, with principal curvatures k1, k2, then show that inf M|k1−k2| = 0....

L3
Geometry
AMR-071-0002
Open

Bass conjecture

v1.3 research notes

Bass conjecture: for every finitely generated $\mathbb Z$-algebra $A$ and every $n\geq0$, is the G-theory group $K'_n(A)$ finitely generated? Equivale...

L3
Algebraic Geometry
AMR-071-0006
Open

Fröberg conjecture on the Hilbert functions of a set of forms

v1.3 research notes

Fröberg conjecture on the Hilbert functions of a set of forms....

L3
Algebraic Geometry
AMR-071-0007
Open

Wikipedia geometry item 7: Fujita conjecture regarding the line bundle $K_{M} \otimes L^{\otimes m}$ constructed from a po…

v1.3 research notes

Fujita conjecture regarding the line bundle $K_{M} \otimes L^{\otimes m}$ constructed from a positive holomorphic line bundle $L$ on a compact complex...

L3
Algebraic Geometry
AMR-071-0008
Open

General elephant problem

v1.3 research notes

General elephant problem: do general elephants have at most Du Val singularities?...

L3
Algebraic Geometry
AMR-071-0013
Open

Wikipedia geometry item 13: Nagata's conjecture on curves, specifically the minimal degree required for a plane algebraic c…

v1.3 research notes

Nagata's conjecture on curves, specifically the minimal degree required for a plane algebraic curve to pass through a collection of very general point...

L3
Algebraic Geometry
AMR-071-0014
Open

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 notes

Nagata–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...

L3
Algebraic Geometry
AMR-071-0015
Open

Nakai conjecture

v1.3 research notes

Nakai conjecture: if a complex algebraic variety has a ring of differential operators generated by its contained derivations, then it must be smooth....

L3
Algebraic Geometry
AMR-071-0017
Open

Wikipedia geometry item 17: Section conjecture on splittings of group homomorphisms from fundamental groups of complete smo…

v1.3 research notes

Section conjecture on splittings of group homomorphisms from fundamental groups of complete smooth curves over finitely-generated fields $k$ to the Ga...

L3
Algebraic Geometry
AMR-071-0021
Open

Zariski multiplicity conjecture on the topological equisingularity and equimultiplicity of varieties at singular points

v1.3 research notes

Zariski multiplicity conjecture on the topological equisingularity and equimultiplicity of varieties at singular points...

L3
Algebraic Geometry
AMR-071-0022
Open

Are infinite sequences of flips possible in dimensions greater than 3

v1.3 research notes

Are infinite sequences of flips possible in dimensions greater than 3?...

L3
Algebraic Geometry
AMR-071-0025
Open

The covering problem of Rado

v1.3 research notes

The covering problem of Rado: if the union of finitely many axis-parallel squares has unit area, how small can the largest area covered by a disjoint ...

L3
Geometry
AMR-071-0026
Open

The Erdős–Oler conjecture

v1.3 research notes

The Erdős–Oler conjecture: when $n$ is a triangular number, packing $n-1$ circles in an equilateral triangle requires a triangle of the same size as p...

L3
Geometry
AMR-071-0027
Open

Wikipedia geometry item 27: The disk covering problem about finding the smallest real number $r(n)$ such that $n$ disks of…

v1.3 research notes

The disk covering problem about finding the smallest real number $r(n)$ such that $n$ disks of radius $r(n)$ can be arranged in such a way as to cover...

L3
Geometry
AMR-071-0050
Open

The Kobon triangle problem on triangles in line arrangements

v1.3 research notes

The Kobon triangle problem on triangles in line arrangements...

L3
Geometry
AMR-071-0051
Open

The Kusner conjecture

v1.3 research notes

The Kusner conjecture: at most $2d$ points can be equidistant in $L^1$ spaces...

L3
Geometry
AMR-071-0052
Open

The McMullen problem on projectively transforming sets of points into convex position

v1.3 research notes

The McMullen problem on projectively transforming sets of points into convex position...

L3
Geometry
AMR-071-0053
Open

Opaque forest problem on finding opaque sets for various planar shapes

v1.3 research notes

Opaque forest problem on finding opaque sets for various planar shapes...

L3
Geometry
AMR-071-0057
Open

For each arrangement of points in which the rectilinear crossing number is minimized, is the number of halving lines maximized

v1.3 research notes

For each arrangement of points in which the rectilinear crossing number is minimized, is the number of halving lines maximized?...

L3
Geometry
AMR-071-0059
Open

The Atiyah conjecture on configurations on the invertibility of a certain $n$-by-$n$ matrix depending on $n$ points in $\mathbb{R}^{3}$

v1.3 research notes

The Atiyah conjecture on configurations on the invertibility of a certain $n$-by-$n$ matrix depending on $n$ points in $\mathbb{R}^{3}$...

L3
Geometry
AMR-071-0062
Open

Connelly’s blooming conjecture

v1.3 research notes

Connelly’s blooming conjecture: Does every net of a convex polyhedron have a blooming?...

L3
Geometry
AMR-071-0068
Open

What is the lowest number of faces possible for a holyhedron

v1.3 research notes

What is the lowest number of faces possible for a holyhedron?...

L3
Geometry
AMR-071-0078
Open

Wikipedia geometry item 78: Can every spherical non-convex polyhedron that tiles space by translation have its faces groupe…

v1.3 research notes

Can every spherical non-convex polyhedron that tiles space by translation have its faces grouped into patches with the same combinatorial structure as...

L3
Geometry
AMR-071-0081
Open

Is there a general expression for the minimum ropelength of an arbitrary closed knot

v1.3 research notes

Is there a general expression for the minimum ropelength of an arbitrary closed knot?...

L3
Geometry
AMR-071-0084
Open

Is there a general expression for how much the ends of a long rope of radius 1 get closer when a tight open knot is tied into it

v1.3 research notes

Is there a general expression for how much the ends of a long rope of radius 1 get closer when a tight open knot is tied into it?...

L3
Geometry
AMR-071-0087
Open

Is there a non-convex polyhedron without self-intersections with more than seven faces, all of which share an edge with each other

v1.3 research notes

Is there a non-convex polyhedron without self-intersections with more than seven faces, all of which share an edge with each other?...

L3
Geometry
AMR-073-0001
Open

Babai's problem

v1.3 research notes

Babai's problem: which groups are Babai invariant groups?...

L3
Graph Theory
AMR-074-0100
Open

Friedman–Simpson Interpretability Conjecture

v1.3 research notes

For any finite sets $X$ and $Y$ of published mathematical theorems expressible in second-order arithmetic, is either $\mathsf{RCA}_0+X$ interpretable ...

L3
Logic
AMR-074-0112
Open

Cancellation and Schröder–Bernstein for Torsion Abelian Groups

v1.3 research notes

Are the following statements equivalent to $\Pi^1_1\text{-}\mathsf{CA}_0$? (i) If countable torsion abelian groups $G,H$ satisfy $G\oplus G\cong H\opl...

L3
Logic
AMR-074-0114
Open

One-Point Compactification for MF Spaces

v1.3 research notes

Determine the reverse-mathematical strength of Alexandroff's one-point compactification theorem for countably based MF spaces....

L3
Logic
AMR-074-0115
Open

Metrization of Proper MF Spaces

v1.3 research notes

Determine the reverse-mathematical strength of the assertion that a proper MF space is metrizable if and only if it is regular....

L3
Logic
AMR-074-0119
Open

Furstenberg–Zimmer Structure Theorem

v1.3 research notes

Over $\mathsf{RCA}_0$, does the Furstenberg–Zimmer structure theorem imply $\Pi^1_1\text{-}\mathsf{CA}_0$?...

L3
Logic
AMR-074-0122
Open

Lengths of Bounded-Rank Linear-Order WQOs

v1.3 research notes

For an ordinal $\alpha$, determine the length (maximal order type) of the well-quasi-order $L_\alpha$ of countable linear orders of Hausdorff rank bel...

L3
Logic
AMR-074-0124
Open

Strengths of Laver and Nash–Williams BQO Theorems

v1.3 research notes

Determine the reverse-mathematical strengths of Laver's labeled-linear-order theorem $\mathsf{LAV}$ and the Nash–Williams bqo transfinite-sequence the...

L3
Logic
AMR-074-0131
Open

Weak Infinitary Comprehension versus Weak Choice

v1.3 research notes

Is weak-$L_{\omega_1,\omega}$-$\mathsf{CA}$ equivalent to weak-$\Sigma^1_1$-$\mathsf{AC}_0$?...

L3
Logic