English
Related papers

Related papers: Conformal maps from a 2-torus to the 4-sphere

200 papers

We consider the generalization of classical Blaschke's Problem to higher codimension case, characterizing Darboux pair of isothermic surfaces and dual S-Willmore surfaces as the only non-trivial surface pairs that envelop a 2-sphere…

Differential Geometry · Mathematics 2008-11-26 Xiang Ma

Isothermic surfaces are surfaces which allow a conformal curvature line parametrisation. They form an integrable system, and Darboux transforms of isothermic surfaces obey Bianchi permutability: for two distinct spectral parameters the…

Differential Geometry · Mathematics 2022-05-31 Joseph Cho , Katrin Leschke , Yuta Ogata

In this paper we give an explicit parametrisation of the moduli space of equivariant harmonic maps from a 2-torus to the 3-sphere. As Hitchin proved, a harmonic map of a 2-torus is described by its spectral data, which consists of a…

Differential Geometry · Mathematics 2020-08-26 Emma Carberry , Ross Ogilvie

The spinor representation is developed for conformal immersions of Riemann surfaces into space. We adapt the approach of Dennis Sullivan, which treats a spin structure on a Riemann surface M as a complex line bundle S whose square is the…

dg-ga · Mathematics 2016-08-31 Rob Kusner , Nick Schmitt

We construct the smooth, compact moduli space of similarity classes of labeled, oriented triangles. The space, denoted $\mathfrak D$, is a connected sum of three projective planes, and projects via blowdown to two shape spaces that have…

Algebraic Geometry · Mathematics 2025-08-01 Eric Brussel , Madeleine Goertz , Elijah Guptill , Kelly Lyle

We prove that every locally conformally flat metric on a closed, oriented hyperbolic 4-manifold with scalar curvature bounded below by -12 satisfies Schoen's conjecture. We also classify all closed Riemannian 4-manifolds of positive scalar…

Differential Geometry · Mathematics 2025-12-16 Jialong Deng

Let $H^4$ denote the hyperbolic four-space. Given a bordered Riemann surface, $M$, we prove that every smooth conformal superminimal immersion $\overline M\to H^4$ can be approximated uniformly on compacts in $M$ by proper conformal…

Differential Geometry · Mathematics 2023-06-26 Franc Forstneric

By adopting the standard definition of diffeomorphisms for a Regge surface we give an exact expression of the Liouville action both for the sphere and the torus topology in the discretized case. The results are obtained in a general way by…

High Energy Physics - Theory · Physics 2009-10-30 Pietro Menotti , Pier Paolo Peirano

We define a transformation on harmonic maps from a Riemann surface into the 2-sphere which depends on a complex parameter, the so-called mu-Darboux transformation. In the case when the harmonic map N is the Gauss map of a constant mean…

Differential Geometry · Mathematics 2014-07-24 F. E. Burstall , J. F. Dorfmeister , K. Leschke , A. Quintino

We consider smooth isotropic immersions from the 2-dimensional torus into $R^{2n}$, for $n \geq 2$. When $n = 2$ the image of such map is an immersed Lagrangian torus of $R^4$. We prove that such isotropic immersions can be approximated by…

Differential Geometry · Mathematics 2019-05-06 François Jauberteau , Yann Rollin , Samuel Tapie

Topologically, a compact Riemann surface $X$ of genus $g$ is a $g$-holed torus (a sphere with $g$ handles). This paper is an introduction to the theory of compact Riemann surfaces and algebraic curves. It presents the basic ideas and…

Algebraic Geometry · Mathematics 2009-03-13 A. Lesfari

We show that every finite type polarised curve in the conformal $2$-sphere with a polynomial conserved quantity admits a resonance point, under a non-orthogonality assumption on the conserved quantity. Using this fact, we deduce that every…

Differential Geometry · Mathematics 2025-04-01 Joseph Cho , Katrin Leschke , Yuta Ogata

The notion of a generalized harmonic inverse mean curvature surface in the Euclidean four-space is introduced. A backward B\"{a}cklund transform of a generalized harmonic inverse mean curvature surface is defined. A Darboux transform of a…

Differential Geometry · Mathematics 2013-04-11 Katsuhiro Moriya

In this paper we develop the theory of approximation for holomorphic null curves in the special linear group ${\rm SL}_2(\mathbb{C})$. In particular, we establish Runge, Mergelyan, Mittag-Leffler, and Carleman type theorems for the family…

Differential Geometry · Mathematics 2025-07-28 Antonio Alarcon , Jorge Hidalgo

As is well-known, there exist nonconstant holomorphic maps from the plane into the Riemann sphere $\PP^1$ minus two points, the simplest example of which is an explicit realization of the uniformization map given by applying the exponential…

Complex Variables · Mathematics 2007-05-23 Steven Shin-Yi Lu , Gregery T. Buzzard

A discrete conformal map (DCM) maps the square lattice to the Riemann sphere such that the image of every irreducible square has the same cross-ratio. This paper shows that every periodic DCM can be determined from spectral data (a…

Differential Geometry · Mathematics 2014-09-16 U. Hertrich-Jeromin , I. McIntosh , P. Norman , F. Pedit

This paper studies conformal biharmonic immersions. We first study the transformations of Jacobi operator and the bitension field under conformal change of metrics. We then obtain an invariant equation for a conformal biharmonic immersion…

Differential Geometry · Mathematics 2008-08-19 Ye-Lin Ou

We study sequences $f_k:\Sigma_k \to \R^n$ of conformally immersed, compact Riemann surfaces with fixed genus and Willmore energy ${\cal W}(f) \leq \Lambda$. Assume that $\Sigma_k$ converges to $\Sigma$ in moduli space, i.e.…

Differential Geometry · Mathematics 2010-09-30 Ernst Kuwert , Yuxiang Li

We analyze the Seiberg-Witten curve of the six-dimensional N=(1,1) gauge theory compactified on a torus to four dimensions. The effective theory in four dimensions is a deformation of the N=2* theory. The curve is naturally holomorphically…

High Energy Physics - Theory · Physics 2009-11-10 Harry W. Braden , Timothy J. Hollowood

We consider the moduli space of holomorphic principal bundles for reductive Lie groups over Riemann surfaces (possibly with boundaries) and equipped with meromorphic connections. We associate to this space a point-wise notion of quantum…

Mathematical Physics · Physics 2020-07-01 Raphaël Belliard , Bertrand Eynard