arXiv research

Otsuki tori form a countable family of immersed minimal two-dimensional tori in the unitary three-dimensional sphere. According to El Soufi-Ilias theorem, the metrics on the Otsuki tori are extremal for some unknown eigenvalues of the Laplace-Beltrami operator. Despite the fact that the Otsuki tori are defined in quite…

The paper bounds the Morse index and nullity of bipolar surfaces related to Otsuki tori.

Existence of minimal annuli in 3-sphere with boundary on geodesic spheres.

The paper finds rotationally symmetric critical metrics for Laplace eigenvalues on tori.

The $i$-th eigenvalue $λ_i$ of the Laplace-Beltrami operator on a surface can be considered as a functional on the space of all Riemannian metrics of unit volume on this surface. Surprisingly only few examples of extremal metrics for these functionals are known. In the present paper a new countable family of extremal m…

Paper characterizes a special hypersurface in 5D sphere.

New model-independent compact representations of imaginary-time data are presented in terms of the intermediate representation (IR) of analytical continuation. This is motivated by a recent numerical finding by the authors [J. Otsuki et al., arXiv:1702.03056]. We demonstrate the efficiency of the IR through continuous-…

We use a local argument to prove if an $r$-dimensional torus acts isometrically and effectively on a connected $n$-dimensional manifold which has positive $k^\mathrm{th}$-intermediate Ricci curvature at some point, then $r \leq \lfloor \frac{n+k}{2} \rfloor$. This symmetry rank bound generalizes those established by Gr…

This paper explores twisted Lagrangian tori in C^2 and their Hamiltonian stationarity.

Smooth 2-tori in R^4 can be approximated by polyhedral Lagrangian or isotropic tori.

The paper classifies minimal immersions of flat 3- and 4-tori in spheres by their first eigenfunctions.

Characterizes conformal classes of tori using differential geometry.

Study finds non-isotopic transverse tori in Engel manifolds.

We study square-tiled tori, that is, tori obtained from a finite collection of unit squares by parallel side identifications. Square-tiled tori can be parametrized in a natural way that allows to count the number of square-tiled tori tiled by a given number of square tiles. There is a natural $\mathrm{SL}(2,\mathbf{Z})…

New findings on isospectral tori and harmonic maps between flat tori.

Constructs flows of tori in sphere perturbations for Morse homology.

We prove that the conformal immersions of complex two tori into $S^3$ which locally minimize their conformal volume in their conformal class all satisfy some elliptic PDE. We prove that they are either minimal tori, CMC flat tori, elliptic conformally constrained minimal tori or critical point of the area under some fi…

Ellipsoids host infinitely many minimal tori, bifurcating from a 2-torus orbit.

Study of critical tori for mean curvature energies in Killing submersions.

We consider proper-biharmonic flat tori with constant mean curvature (CMC) in spheres and find necessary and sufficient conditions for certain rectangular tori and square tori to admit full CMC proper-biharmonic immersions in $\mathbb{S}^n$, as well as the explicit expressions of some of these immersions.

The Clifford torus is a torus in a three-dimensional sphere. Homogeneous tori are simple generalization of the Clifford torus which still in a three-dimensional sphere. There is a way to construct tori in a three-dimensional sphere using the Hopf fibration. In this paper, all Hamiltonian stationary Lagrangian tori whic…

Isothermic tori with one planar curvature line found and characterized.

For all positive integers n we construct a 1-parameter family of conformal tori of revolution in the 3-sphere with n bulges. These tori arise by Darboux transformations of constant mean curvature tori but do not have constant mean curvature in the 3-sphere.

Study tiling spaces over irrational tori using diffeological classification.

New minimal tori found in curved spaces.

Classifies mapping tori of specific groups, generalizing known results.

Paper explains dynamics of homeomorphisms to mapping tori geometry.

Smooth tori in S^4 are topologically unknotted.

In \cite{BSV}, Borisov, Salamon and Viaclovsky constructed non-standard orthogonal complex structures on flat tori $T^{2n}_{\mathbb R}$ for any $n\geq 3$. We will call these examples BSV-tori. In this note, we show that on a flat $6$-torus, all the orthogonal complex structures are either the complex tori or the BSV-to…

Counts minimal tori in Riemannian manifolds with 6 or more dimensions.

The paper finds non-contractible loops of Legendrian tori from knot families.

The study limits the number of 2-holed tori in knot exteriors.

Engel manifolds show transverse tori can be made to have various formal invariants.

We show that for $m>n\geq 2$, there are at least two exact isotropic $n$-tori in $\mathbb{C}^m$ which are not Hamiltonian isotopic in $\mathbb{C}^m$, even though they are smoothly isotopic as isotropic $n$-tori. We apply this discovery to obtain more distinct non-exact isotropic tori in $\mathbb{C}^m$.

We present a deformation for constant mean curvature tori in the 3-sphere. We show that the moduli space of equivariant constant mean curvature tori in the 3-sphere is connected, and we classify the minimal, the embedded, and the Alexandrov embedded tori therein. We conclude with an instability result.

New non-Kähler examples of generalized Kähler manifolds constructed via mapping tori.

We study the poset of Hamiltonian tori for polygon spaces. We determine some maximal elements and give examples where maximal Hamiltonian tori are not all of the same dimension.

We found unique tori with same curvatures using isometric transformations.

The study characterizes subgroups of mapping tori of free groups.

Free maps exist on low-dimensional tori and closed surfaces.

Delaunay tori minimize Willmore energy under isoperimetric constraints.

Minimal volume entropy vanishes for mapping tori over 3-manifolds.

Study higher rank inner products and their tilings to describe tori degenerations.

We compute lower bounds for the Morse index and nullity of constant mean curvature tori of revolution in the three-dimensional unit sphere. In particular, all such tori have index at least five, with index growing at least linearly with respect to the number of the surfaces' bulges, and the index of such tori can be ar…

New methods create full discretized isothermic tori in Euclidean spaces.

Stability of tori under curvature conditions is proven.

We produce a new general family of flat tori in R^4, the first one since Bianchi's classical works in the 19th century. To construct these flat tori, obtained via small perturbation of certain Hopf tori in S^3, we first present a global description of all isometric immersions of R^2 into R^4 with flat normal bundle.

Study centers of quantum tori and skein algebras for even roots of unity.