Research
On-device research index

arXiv research

A locally-built, LLM-digested index of recent arXiv papers in quant finance, geometry/topology, and statistical ML — keyword search served straight from SQLite on this machine.

168,742 papers · 148 categories

Trend · papers per month

1122 · Jun 200819922001200920172026
33 results for Costa Rica

Metaheuristics improve yield curve estimation for Costa Rica.

problem Estimating the yield curve for Costa Rica using historical data.
method Used Nelson-Siegel and Svensson models with four metaheuristics (Ant colony, Genetic, Particle Swarm, Simulated Annealing) for optimization.
result Metaheuristics achieved better results than classical methods, especially Particle Swarm and Simulated Annealing.

Climate has been an important factor in shaping the distribution and incidence of dengue cases in tropical and subtropical countries. In Costa Rica, a tropical country with distinctive micro-climates, dengue has been endemic since its introduction in 1993, inflicting substantial economic, social, and public health repe…

2019-07-30abs ↗pdf ↗

This paper evaluates investment risks in LATAM AI startups using DCF method.

problem Unique challenges and risks faced by LATAM tech startups.
method Total Addressable Market (TAM), Serviceable Available Market (SAM), and Serviceable Obtainable Market (SOM) metrics; Discounted Cash Flow (DCF) method.
result Developed a ranking of emerging powers in Latin America for tech startup investment.

Identifies causal effects in LiNGAM models with latent variables.

problem Identifying causal effects in LiNGAM models with latent confounders.
method Complete graphical characterization and efficient algorithms for certification. RICA adaptation for estimation.
result Efficient algorithms and RICA adaptation for estimating causal effects.

The aim of this work is to extend the results of S. Nayatani about the index and the nullity of the Gauss map of the Costa-Hoffman-Meeks surfaces for values of the genus bigger than 37. That allows us to state that these minimal surfaces are non degenerate for all the values of the genus in the sense of the definition …

2008-06-11abs ↗pdf ↗

We construct higher genus Riemann's minimal surfaces properly embedded in the Euclidean space. To do that we glue end by end a Costa-Hoffman-Meeks examples to two halves genus zero Riemann's minimal surfaces. In first we need to perform a deformation of a Costa-Hoffman-Meeks example to prescribe the flux vector along t…

2005-11-17abs ↗pdf ↗

The paper constructs surfaces of high genus with three ends.

problem Creating minimal surfaces of high genus with specific properties.
method One-parameter family of minimal surfaces constructed in Euclidean 3-space.
result The family includes the Costa-Hoffman-Meeks surfaces with two catenoidal ends and a flat middle end.

We give a positive answer to M. Traizet's open question about the existence of complete embedded minimal surfaces with Scherk-ends without planar geodesics. In the singly periodic case, these examples get close to an extension of Traizet's result concerning asymmetric complete minimal submanifolds of Euclidean space wi…

2004-08-30abs ↗pdf ↗

In this paper, we obtain classification of four-dimensional Einstein manifolds with positive Ricci curvature and pinched sectional curvature. In particular, the first result concerns with an upper bound of sectional curvature, improving a theorem of E. Costa. The second is a generalization of D. Yang's result assuming …

2016-12-19abs ↗pdf ↗

In 2008-2009, F. Costa and C. Herdeiro proposed a new gravito-electromagnetic analogy, based on tidal tensors. We show that connections on the tangent bundle of the space-time manifold can help not only in finding a covnenient geometrization of their ideas, but also a common mathematical description of the main equatio…

2011-11-06abs ↗pdf ↗

In this paper a lower bound for the ADM mass is given in terms of the angular momenta and charges of black holes present in axisymmetric initial data sets for the Einstein-Maxwell equations. This generalizes the mass-angular momentum-charge inequality obtained by Chrusciel and Costa to the case of multiple black holes.…

2015-02-23abs ↗pdf ↗

Gaussian kernels on complex manifolds are never positive definite.

problem Analyzing positive definiteness of Gaussian kernels on non-simply-connected Riemannian manifolds.
method Combining recent preprint analysis and classical Riemannian geometry comparison theorems.
result Gaussian kernels are never positive definite on non-simply-connected closed Riemannian manifolds.

Mitsumatsu constructed leafwise symplectic structures of certain codimension one foliations of the 5-sphere. This inspired the present author to improve his result on convergence of contact structure to foliation. We describe convergence of contact strcture to leafwise symplectic foliation by means of confoliation equi…

2012-02-04abs ↗pdf ↗

We survey what is known about minimal surfaces in R3\bold R^3 that are complete, embedded, and have finite total curvature. The only classically known examples of such surfaces were the plane and the catenoid. The discovery by Costa, early in the last decade, of a new example that proved to be embedded sparked a great…

1995-08-09abs ↗pdf ↗

Study on minimal surfaces with free boundary in a half-space, improving index estimates.

problem Non-existence of index two embedded minimal surfaces with free boundary in a half-space.
method Improved estimates of Neumann and Dirichlet indices, simplified proof of lower bounds.
result Answered Ambrozio et al.'s question and provided new lower bounds.

Study new bounds on TC of spaces with subgroup inclusions.

problem Lower bounds on TC of spaces with subgroup inclusions.
method Generalizes TC results from aspherical spaces to spaces with subgroup inclusions.
result Establishes new lower bounds on sequential TCs of aspherical spaces.

The study finds conditions for nonmaximal topological complexity of manifolds with abelian fundamental groups.

problem Conditions for nonmaximal topological complexity of manifolds with abelian fundamental groups.
method Analyzes conditions and examples to generalize results on topological complexity and Lusternik-Schnirelmann category.
result Generalizes results on topological complexity and Lusternik-Schnirelmann category for manifolds with abelian fundamental groups.

We add two new 1-parameter families to the short list of known embedded triply periodic minimal surfaces of genus 4 in R3\mathbb{R}^3. Both surfaces can be tiled by minimal pentagons with two straight segments and three planar symmetry curves as boundary. In one case (which has the appearance of the CLP surface of Schw…

2018-07-23abs ↗pdf ↗

New maxfaces with catenoid or planar ends constructed using node-opening technique.

problem Lack of examples of maxfaces with catenoid or planar ends.
method Adapted node-opening technique to construct maxfaces of high genus.
result Singularities on constructed maxfaces form curves around the waists of the necks, with most singularities being cuspidal edges and the rest swallowtails.

Study of minimal surfaces in 4D with specific ends.

problem Characterize minimal surfaces in R4\mathbb{R}^4 with specific ends.
method Modification of Costa and Hoffman-Meeks method, generalized Weierstrass representation.
result Minimal surfaces with specific ends are JJ-holomorphic under certain conditions.

We develop Teichmuller theoretical methods to construct new minimal surfaces in $\BE^3$ by adding handles and planar ends to existing minimal surfaces in $\BE^3$. We exhibit this method on an interesting class of minimal surfaces which are likely to be embedded, and have a low degree Gaußmap for their genus; the (Weier…

1998-06-17abs ↗pdf ↗

Minimal TIP and TIF found in compact spacetimes, impacting spacetime splitting.

problem Understanding the global structure of spacetimes with compact Cauchy surfaces.
method Analysis of Terminal Indecomposable Past (TIP) and Future (TIF) sets in spacetimes with compact Cauchy surfaces.
result In a spacetime with compact Cauchy surfaces, there is always at least one minimal TIP and one minimal TIF.

We consider minimal surfaces MM which are complete, embedded and have finite total curvature in R3\R^3, and bounded, entire solutions with finite Morse index of the Allen-Cahn equation Δu+f(u)=0inR3Δu + f(u) = 0 \hbox{in} \R^3 . Here f=Wf=-W' with WW bistable and balanced, for instance W(u)=14(1u2)2W(u) =\frac 14 (1-u^2)^2. We assume that …

2009-02-12abs ↗pdf ↗

Given a complete isometric immersion φ:PmNnφ: P^m \longrightarrow N^n in an ambient Riemannian manifold NnN^n with a pole and with radial sectional curvatures bounded from above by the corresponding radial sectional curvatures of a radially symmetric space MwnM^n_w, we determine a set of conditions on the extrinsic curvatur…

2011-12-17abs ↗pdf ↗

A k-submanifold L of an open n-manifold M is called weakly integrable (WI) [resp. strongly integrable (SI)] if there exists a submersion Φ:M\to R^{n-k} such that L\subset Φ^{-1}(0) [resp. L= Φ^{-1}(0)]. In this work we study the following problem, first stated in a particular case by Costa et al. (Invent. Math. 1988): …

2010-12-20abs ↗pdf ↗