The study finds conditions for flat isotropic non-homogeneous tori to be Hamiltonian minimal.
problem Finding conditions for Hamiltonian minimality of isotropic non-homogeneous tori.
method Constructing a family of flat isotropic non-homogeneous tori and finding necessary and sufficient conditions.
result Necessary and sufficient conditions for Hamiltonian minimality of isotropic non-homogeneous tori in H n \mathbb{H}^n H n and C P 2 n + 1 \mathbb{C} \mathrm{P}^{2n+1} C P 2 n + 1 . Classifies smooth isotopy of a specific Lagrangian embedding.
problem Classifying Lagrangian embeddings of a specific form.
method Smooth isotopy classification for all dimensions n ≥ 3 n \ge 3 n ≥ 3 . result Lagrangian embeddings are fully classified up to isotopy.
New method constructs explicit p p p -harmonic functions on Lie groups.
problem Constructing proper p p p -harmonic functions on Lie groups. method Employing complex isoparametric functions to devise a general method.
result First explicit proper p p p -harmonic functions on R m ⋉ R n \mathbb{R}^m \ltimes \mathbb{R}^n R m ⋉ R n and R m ⋉ H 2 n + 1 \mathbb{R}^m \ltimes \mathrm{H}^{2n+1} R m ⋉ H 2 n + 1 . Sharp constants in curl-Sobolev inequalities on spheres determined.
problem Determining sharp constants in curl-Sobolev inequalities on spheres.
method Analyzing conformally invariant Sobolev quotients and using local stability estimates.
result Strict upper bound for the sharp constant of the J 2 J_2 J 2 inequality. Study on holonomy of Obata connection on Joyce hypercomplex manifolds.
problem Analyzing the holonomy of the Obata connection on Joyce hypercomplex manifolds.
method Examining holonomy groups for different Joyce hypercomplex manifolds.
result Holonomy groups are strictly contained in quaternionic general linear group for most Joyce hypercomplex manifolds.
We present a complete classification and the construction of M p ( 2 n + 2 , R ) \mathrm{Mp}(2n+2,\mathbb{R}) Mp ( 2 n + 2 , R ) -equivariant differential operators acting on the principal series representations, associated to the contact projective geometry on R P 2 n + 1 \mathbb{RP}^{2n+1} RP 2 n + 1 and induced from the irreducible M p ( 2 n , R ) \mathrm{Mp}(2n,\mathbb{R}) Mp ( 2 n , R ) -submodules of…
The Gaiotto locus for Sp(2n) is shown to lie in the nilpotent cone.
problem Characterizing the Gaiotto locus for Sp(2n) Lie groups.
method Using symplectic representations and moment maps, analyzing Higgs fields and their closures.
result The Gaiotto locus for Sp(2n) is the irreducible component of the nilpotent cone.
The paper constructs paths of SL2(R) representations for pretzel knots and shows left-orderability conditions.
problem Left-orderability of knot surgery manifolds.
method Explicit construction of continuous paths of SL2(R) representations.
result Fundamental groups of certain knot surgeries are left-orderable.
For a surface group, a new bound is given for conjugator length function.
problem Finding an explicit bound for the conjugator length function of a surface group.
method Detailed analysis of conjugation reductions.
result An explicit bound n − 1 ≤ C L ( 2 n ) ≤ n + 8 g − 1 n-1 \leq \mathrm{CL}(2n) \leq n+8g-1 n − 1 ≤ CL ( 2 n ) ≤ n + 8 g − 1 for the conjugator length function of a surface group. The study of Seifert linking forms for punctured n-manifolds in (2n-1)-space.
problem Understanding Seifert linking forms for punctured n-manifolds.
method Analyzing integer-valued bilinear symmetric forms on H n − 1 ( N 0 ; Z ) H_{n-1}(N_0;\mathbb Z) H n − 1 ( N 0 ; Z ) and proving their realizability. result The value modulo two of the invariant equals a specific intersection formula involving Steifel-Whitney class.
The paper defines Dirichlet domains for Anosov subgroups in Lie groups.
problem Finding finite-sided Dirichlet domains for Anosov subgroups in Lie groups.
method Introducing a sufficient condition for finite-sided Dirichlet domains in semisimple Lie groups for polyhedral Finsler metrics.
result Finitely generated subgroups of semisimple Lie groups can have finite-sided Dirichlet domains under certain conditions.
We describe a construction of Schottky type subgroups of automorphism groups of partially cyclically ordered sets. We apply this construction to the Shilov boundary of a Hermitian symmetric space and show that in this setting Schottky subgroups correspond to maximal representations of fundamental groups of surfaces wit…
We study generalized special cycles on Hermitian locally symmetric spaces Γ \ D Γ\backslash D Γ\ D associated to the groups G = U ( p , q ) G=\mathrm{U}(p,q) G = U ( p , q ) , S p ( 2 n , R ) \mathrm{Sp}(2n,\mathbb{R}) Sp ( 2 n , R ) and O ∗ ( 2 n ) \mathrm{O}^*(2n) O ∗ ( 2 n ) . These cycles are (covered by) locally symmetric spaces associated to subgroups of G G G which are of the same type. Using oscillator…
The paper defines cocycles for positive Anosov representations and constructs affine actions with bounded fundamental domains.
problem Positive Anosov representations into S O ( 2 n , 2 n − 1 ) \mathrm{SO}(2n,2n-1) SO ( 2 n , 2 n − 1 ) . method Definition of cocycles and construction of affine actions with fundamental domains.
result Quotient manifolds are homeomorphic to handlebodies.
This paper completes proofs for left orderable slopes of double twist knots.
problem Proving the left orderability of slopes for double twist knots.
method Continuous families of hyperbolic SL2(R) representations of knot groups.
result Any slope in (-4n, 4m) is a left orderable slope of C(2m+1, -2n).
Study on left orderability of specific knot covers.
problem Determining left orderability of knot covers.
method Computing nonabelian SL2(C) character varieties and analyzing real points.
result Left orderability of fundamental groups of cyclic branched covers.
The paper reduces the required dimension for a Z 2 \mathbb{Z}_2 Z 2 -torus action on positively curved manifolds to half the dimension.
problem Understanding the conditions for Z 2 \mathbb{Z}_2 Z 2 -actions on positively curved manifolds. method Reducing the dimension required for a Z 2 \mathbb{Z}_2 Z 2 -torus action to approximately 2 n / 5 2n/5 2 n /5 . result The manifold remains homotopy equivalent to S n S^n S n , R P n \mathbb{R}\mathrm{P}^{n} R P n , C P n 2 \mathbb{C}\mathrm{P}^{\frac{n}{2}} C P 2 n , or a lens space. New geometry based on Siegel upper half-space with volume formula.
problem Developing a new 3D geometry based on Siegel upper half-space.
method Constructing a geometry fibered over Siegel upper half-space and providing a volume formula.
result Volume of Siegel-Seifert closed manifolds is the fiber circle length times base manifold's Euler characteristic.
Maps between classifying spaces for certain groups are studied, with rational cohomology results.
problem Analyzing maps between classifying spaces for specific groups.
method Study of maps Θ Θ Θ between null-components of homomorphism and based map spaces. result Surjectivity of map Θ Θ Θ in rational cohomology for certain groups, and non-surjectivity for others. The h-principle fails for prelegendrians in fat distributions of corank 2.
problem Investigating the h-principle for fat distributions of corank 2.
method Developed the theory of prelegendrians, including front projection and pseudoholomorphic curve invariants.
result Found an infinite family of non-prelegendrian isotopic tori in the standard fat distribution.
Extends Euler class result to symplectic group.
problem Relationship between bounded Euler class and symplectic rotation number.
method Extends Ghys's result to symplectic group.
result Establishes relationship between bounded Euler class and symplectic rotation number.
A locally conformally Kähler (lcK) manifold is a complex manifold ( M , J ) (M,J) ( M , J ) together with a Hermitian metric g g g which is conformal to a Kähler metric in the neighbourhood of each point. In this paper we obtain three classification results in locally conformally Kähler geometry. The first one is the classification of con…
The paper proves nonvanishing cohomology for ball quotient fundamental groups.
problem Proving nonvanishing cohomology for ball quotient fundamental groups.
method Using arithmetic lattices and profinite completions, the paper constructs an open subgroup with nontrivial cohomology.
result The virtual cohomological dimension of the fundamental group is at least 2 n 2n 2 n . The coarea formula is proven for Heisenberg group maps, addressing open questions.
problem Proving the coarea formula for Lipschitz maps from the Heisenberg group to Euclidean space.
method Introducing a new integral to define symplectic area of curves and proving convergence conditions.
result The coarea formula is established for C H 1 C^1_{\mathrm{H}} C H 1 maps from the Heisenberg group to R 2 n \mathbb{R}^{2n} R 2 n . Proof shows volumes of certain geometric representations are always integers.
problem Integrality of volumes of specific geometric representations.
method Elementary, combinatorial-geometrical proof.
result Volumes of representations are integers when n ≥ 2 n \geq 2 n ≥ 2 . Constructs Kleinian groups from free groups via hyperbolization.
problem Creating Kleinian groups from free groups.
method Direct product of rank 2 free groups and strict hyperbolization.
result Description of limit set and its topological dimension.
We find all extremal Lagrangian tori in symplectic unit balls and some toric domains.
problem Characterize extremal Lagrangian tori in symplectic manifolds.
method Analyzing symplectic area and using geometric properties of toric domains.
result Every extremal Lagrangian torus in the unit ball is on the boundary.
Let R R R be an infinite commutative ring with identity and n ≥ 2 n\geq 2 n ≥ 2 be an integer. We prove that for each integer i = 0 , 1 , ⋯ , n − 2 , i=0,1,\cdots ,n-2, i = 0 , 1 , ⋯ , n − 2 , the L 2 L^{2} L 2 -Betti number b i ( 2 ) ( G ) = 0 , b_{i}^{(2)}(G)=0, b i ( 2 ) ( G ) = 0 , \ when G = G L n ( R ) G=\mathrm{GL}_{n}(R) G = GL n ( R ) the general linear group, S L n ( R ) \mathrm{SL}_{n}(R) SL n ( R ) the special linear group, % E_{n}(R) the group generated by…
In this paper we construct complex contact structures on C 2 n + 1 \mathbb{C}^{2n+1} C 2 n + 1 for any n ≥ 1 n\ge 1 n ≥ 1 with the property that every holomorphic Legendrian map C → C 2 n + 1 \mathbb{C}\to \mathbb{C}^{2n+1} C → C 2 n + 1 is constant. In particular, these contact structures are not globally contactomorphic to the standard complex contact structure on $\mat…
The study finds non-uniform lattices with thin Hitchin representations in specific Lie groups.
problem Finding thin Hitchin representations in non-uniform lattices of Lie groups.
method Arithmetic methods to construct thin Hitchin representations.
result Infinitely many orbits of thin Hitchin representations in non-uniform lattices.
Let M M M be a connected open Riemann surface. We prove that the space L ( M , C 2 n + 1 ) \mathscr L(M,\mathbb C^{2n+1}) L ( M , C 2 n + 1 ) of all holomorphic Legendrian immersions of M M M into C 2 n + 1 \mathbb C^{2n+1} C 2 n + 1 , n ≥ 1 n\geq 1 n ≥ 1 , endowed with the standard holomorphic contact structure, is weakly homotopy equivalent to the space C ( M , S 4 n − 1 ) \mathscr C(M,\mathbb S^{4n-1}) C ( M , S 4 n − 1 ) o…
We classify generalized distance-squared mappings of R n + 1 \mathbb{R}^{n+1} R n + 1 into R 2 n + 1 \mathbb{R}^{2n+1} R 2 n + 1 ( n ≥ 1 n\ge 1 n ≥ 1 ) having generic central points. Moreover, we show that there does not exist a universal bad set Σ ⊂ ( R n + 1 ) 2 n + 1 Σ\subset (\mathbb{R}^{n+1})^{2n+1} Σ ⊂ ( R n + 1 ) 2 n + 1 in the case of this dimension-pair.
New methods prove non-squeezing in locally conformal symplectic geometry.
problem Non-squeezing theorem in locally conformal symplectic geometry.
method Generating functions and spectral selectors for lcs Hamiltonian diffeomorphisms.
result Proves a non-squeezing theorem in S 1 i m e s R 2 n i m e s S 1 S^1 imes \mathbb{R}^{2n} imes S^1 S 1 im es R 2 n im es S 1 . Holonomy invariants from S L 2 ( C ) \mathrm{SL}_2(\mathbb{C}) SL 2 ( C ) link complements detect link geometry.
problem Detecting geometric information about links using algebraic quantum invariants.
method Enhanced RT construction with S L 2 ( C ) \mathrm{SL}_2(\mathbb{C}) SL 2 ( C ) holonomy representations. result Holonomy invariants J N \mathrm{J}_N J N compute Reidemeister torsion for N = 2 N=2 N = 2 . Minimal Kaehler submanifolds up to codimension four are studied.
problem Characterizing Kaehler submanifolds in high codimensions.
method Analyzing isometric immersions and compositions of submanifolds.
result Holomorphicity or composition of submanifolds with specific properties.
The study finds surface subgroups in cocompact lattices of H 2 n H^{2n} H 2 n for n ≥ 2 n\geq2 n ≥ 2 .
problem Proving the existence of surface subgroups in cocompact lattices of H 2 n H^{2n} H 2 n for n ≥ 2 n\geq2 n ≥ 2 . method Analyzing cocompact lattices in S O ( 2 n , 1 ) \mathrm{SO}(2n,1) SO ( 2 n , 1 ) for n ≥ 2 n\geq2 n ≥ 2 . result The existence of surface subgroups within any cocompact lattice Γ Γ Γ in S O ( 2 n , 1 ) \mathrm{SO}(2n,1) SO ( 2 n , 1 ) for n ≥ 2 n\geq2 n ≥ 2 . The paper classifies topological properties of specific geometric forms on manifolds.
problem Classifying topological properties of closed G ~ 2 \widetilde{\mathrm{G}}_2 G 2 , S L ( 3 ; C ) \mathrm{SL}(3;\mathbb{C}) SL ( 3 ; C ) and S L ( 3 ; R ) 2 \mathrm{SL}(3;\mathbb{R})^2 SL ( 3 ; R ) 2 forms. method Algebraic and topological techniques, including characteristic classes and obstruction theory, with recent h h h -principles. result Complete classification of closed S L ( 3 ; C ) \mathrm{SL}(3;\mathbb{C}) SL ( 3 ; C ) forms up to homotopy. If Γ < P S L ( 2 , C ) Γ<\mathrm{PSL}(2,\mathbb{C}) Γ < PSL ( 2 , C ) is a lattice, we define an invariant of a representation Γ → P S L ( n , C ) Γ\rightarrow \mathrm{PSL}(n,\mathbb{C}) Γ → PSL ( n , C ) using the Borel class β ( n ) ∈ H c 3 ( P S L ( n , C ) , R ) β(n)\in \mathrm{H}^3_\mathrm{c}(\mathrm{PSL}(n,\mathbb{C}),\mathbb{R}) β ( n ) ∈ H c 3 ( PSL ( n , C ) , R ) . We show that the invariant is bounded and its maximal value is attained by conjugation of t…
Two new proofs of Gromov's non-squeezing theorem using curve reparametrization and gradient bounds.
problem Gromov's non-squeezing theorem in symplectic geometry.
method Reparametrization of pseudo-holomorphic curves and application of mean value inequality or Gromov-Schwarz lemma.
result Uniform bounds on the gradient of pseudo-holomorphic curves leading to compactness of moduli space.
We find a presentation of symplectic Steinberg modules and show vanishing cohomology for certain groups.
problem Cohomology vanishing for specific groups and modules.
method Presented a symplectic Steinberg module and used it to prove cohomology vanishing.
result Cohomology of Sp 2 n ( Z ) \operatorname{Sp}_{2n}(\mathbb{Z}) Sp 2 n ( Z ) vanishes in a specific degree for n ≥ 2 n \geq 2 n ≥ 2 . Let M 2 n M^{2n} M 2 n denote a closed ( n − 1 ) (n-1) ( n − 1 ) -connected smoothable topological 2 n 2n 2 n -manifold. We show that the group C ( M 2 n ) \mathcal{C}(M^{2n}) C ( M 2 n ) of concordance classes of smoothings of M 2 n M^{2n} M 2 n is isomorphic to the group of smooth homotopy spheres Θ ‾ 2 n \overlineΘ_{2n} Θ 2 n for n = 4 n=4 n = 4 or 5 5 5 , the concordance inertia group I c ( M 2 n ) = 0 I_c(M^{2n})=0 I c ( M 2 n ) = 0 for $…
For n ≥ 1 n \geq 1 n ≥ 1 , the twistor space Z ( S 2 n ) \mathfrak{Z}(\mathbb{S}^{2n}) Z ( S 2 n ) of the conformal 2 n 2n 2 n -sphere is biholomorphic to the Zariski closure, taken in the complex Grassmannian manifold G ( n + 1 , 2 n + 2 ) \mathbf{G}(n+1, 2n+2) G ( n + 1 , 2 n + 2 ) , of the set of graphs of skew-symmetric linear endomorphism of C n + 1 \mathbb{C}^{n+1} C n + 1 . We use this fact to describe a nat…
The paper studies submanifolds of Euclidean space from Kaehler manifolds.
problem Understanding submanifolds of Euclidean space from Kaehler manifolds.
method Analyzing conformal immersions and isometric embeddings.
result Local constructions of submanifolds from Kaehler manifolds.
The study proves non-existence of hypercomplex structures on SL(3,R) and finds one on SL(2n+1,C).
problem Proving the non-existence of hypercomplex structures on specific Lie groups.
method Revising the classification of complex structures and using a complex product structure to find hypercomplex structures.
result No left-invariant hypercomplex structures on SL(3,R), and a new hypercomplex structure on SL(2n+1,C).
Positive paths connect diffeomorphisms on contact manifolds.
problem Defining and analyzing positivity in diffeomorphism groups of manifolds with contact structures.
method By examining paths of diffeomorphisms that are positively transverse to the contact distribution, showing flexibility and connecting diffeomorphisms.
result Any two diffeomorphisms on standard contact structure of R^(2n+1) can be connected by a positive path.
In this paper, firstly, for some 4 n 4n 4 n -dimensional almost complex manifolds M i , 1 ≤ i ≤ α M_{i}, ~1\le i \le α M i , 1 ≤ i ≤ α , we prove that ( ♯ i = 1 α M i ) ♯ ( α − 1 ) C P 2 n \left(\sharp_{i=1}^α M_{i}\right) \sharp (α{-}1) \mathbb{C} P^{2n} ( ♯ i = 1 α M i ) ♯ ( α − 1 ) C P 2 n must admits an almost complex structure, where α α α is a positive integer. Secondly, for a 2 n 2n 2 n -dimensional almost complex manifold M M M , we…
Let Γ Γ Γ be a finitely generated group and G G G a real form of S L n ( C ) \mathrm{SL}_n(\mathbb{C}) SL n ( C ) . We propose a definition for the G G G -character variety of Γ Γ Γ as a subset of the S L n ( C ) \mathrm{SL}_n(\mathbb{C}) SL n ( C ) -character variety of Γ Γ Γ . We consider two anti-holomorphic involutions of the S L n ( C ) \mathrm{SL}_n(\mathbb{C}) SL n ( C ) character variet…
The study restricts Anosov subgroups of Sp(2n,R) based on subset Θ.
problem Characterizing Anosov subgroups of Sp(2n,R) based on subset Θ.
method Analyzing the structure of Anosov subgroups in terms of subset Θ.
result Anosov subgroups of Sp(2n,R) are virtually free or surface groups if Θ contains an odd integer, otherwise they are not.