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.

168,657 papers · 148 categories

Trend · papers per month

15304560 · May 202619922001200920172026
48 results for logarithmic spiral

We construct helicoid-like embedded minimal disks with axes along self-similar curves modeled on logarithmic spirals. The surfaces have a self-similarity inherited from the curves and the nature of the construction. Moreover, inside of a "logarithmic cone", the surfaces are embedded.

2014-04-28abs ↗pdf ↗

The paper finds that circles and logarithmic spirals are the only constant-speed ramps for a specific force field.

problem Determining planar curves for constant-speed motion under specific force conditions.
method Analyzing the motion of a particle under friction and a central force field.
result Every solution to the constant-speed motion problem approaches either a circle or a logarithmic spiral.

We show that there is no bi-Lipschitz homeomorphism of R2\mathbb{R}^2 that maps a spiral with a sub-exponential decay of winding radii to an unwinded arc. This result is sharp as shows an example of a logarithmic spiral.

2016-03-10abs ↗pdf ↗

Paper proves rigidity of Doyle spirals in hexagonal lattice circle packings.

problem Proving Doyle conjecture for hexagonal lattice circle packings.
method Using Liouville theorem of discrete harmonic functions based on logarithmic radii ratio observation.
result Proves rigidity of Doyle spirals in hexagonal lattice circle packings with bounded radii ratios.

Let MM be a pinched negatively curved Riemannian manifold, whose unit tangent bundle is endowed with a Gibbs measure mFm_F associated to a potential FF. We compute the Hausdorff dimension of the conditional measures of mFm_F. We study the mFm_F-almost sure asymptotic penetration behaviour of locally geodesic lines of…

2014-05-09abs ↗pdf ↗

The Cornu spirals on plane are the curves whose curvatures are linear. Generalized planar cornu spirals and Euler spirals in E^3, the curves whose curvatures are linear are defined in [1,5]. In this study, these curves are presented as the ratio of two rational linear functions. Also here, generalized Euler spirals in …

2012-01-31abs ↗pdf ↗

This note is the updated outline of the article "Interpolational properties of planar spiral curves", Fund. and Applied Math., 2001, Vol.7, N.2, 441-463, published in Russian. The main result establishes boundary regions for spiral and piecewise spiral splines, matching given data. The width of such region can serve as…

2012-11-14abs ↗pdf ↗

Vogt's theorem, concerning boundary angles of a convex arc with monotonic curvature (spiral arc), is taken as a starting point to establish basic properties of spirals. The theorem is expanded by removing requirements of convexity and curvature continuity; the cases of inflection and multiple windings are considered. P…

2006-01-18abs ↗pdf ↗

This paper characterizes spiral Delone sets in higher dimensions.

problem To extend the theory of spiral sets to higher dimensions and show the existence of spiral Delone sets.
method Characterized Delone property of spiral sets in terms of packing and covering conditions for spherical sequences.
result Construction of explicit spiral Delone sets in \(\mathbb{R}^n\) for all \(n \ge 2\).

A method is proposed to construct spiral curves by inversion of a spiral arc of parabola. The resulting curve is rational of 4-th order. Proper selection of the parabolic arc and parameters of inversion allows to match a wide range of boundary conditions, namely, tangents and curvatures at the endpoints, including thos…

2009-02-27abs ↗pdf ↗

In this study, some characterizations of Euler spirals in E_1^{3} have been presented by using their main property that their curvatures are linear. Moreover, discussing some properties of Bertrand curves and helices, the relationship between these special curves in E_1^{3} have been investigated with different theorem…

2012-01-31abs ↗pdf ↗

Given a negatively curved geodesic metric space M, we study the asymptotic penetration behaviour of geodesic lines of M in small neighbourhoods of closed geodesics and of other compact convex subsets of M. We define a spiraling spectrum which gives precise information on the asymptotic spiraling lengths of geodesic lin…

2008-06-11abs ↗pdf ↗

A class of spiral minimal surfaces in E^3 is constructed using a symmetry reduction. The new surfaces are invariant with respect to the composition of rotation and dilatation. The solutions are obtained in closed form %through the Legendre transformation and their asymptotic behaviour is described.

2006-02-20abs ↗pdf ↗

We provide a detailed description of solutions of Curve Shortening in Rn\R^n that are invariant under some one-parameter symmetry group of the equation, paying particular attention to geometric properties of the curves, and the asymptotic properties of their ends. We find generalized helices, and a connection with curv…

2012-07-17abs ↗pdf ↗

We present a confidence-based single-layer feed-forward learning algorithm SPIRAL (Spike Regularized Adaptive Learning) relying on an encoding of activation spikes. We adaptively update a weight vector relying on confidence estimates and activation offsets relative to previous activity. We regularize updates proportion…

2016-11-18abs ↗pdf ↗

Two new invariants that are closely related to Milnor's curvature-torsion invariant are introduced. The first, the spiral index of a knot, captures the minimum number of maxima among all knot projections that are free of inflection points. This invariant is closely related to both the bridge and braid index of the knot…

2009-03-03abs ↗pdf ↗

A limaçon-like curve, allowing 2π-transition with monotone curvature between concentric curvature elements, is presented. The curve is 4th degree algebraic, 4th degree rational, and shares other common features with Pascal's limaçon.

2013-09-22abs ↗pdf ↗

The paper explores geometric properties of interception curves on planes and spheres.

problem Geometric properties of interception curves defined by differential equations.
method Parametric representation and spherical curve defined by Gudermannian function.
result Symmetry/asymmetry between spherical and planar cases, connections to lemniscate constants.

What are the possible shapes of various things and why? For instance, when a closed wire or a frame is dipped into a soap solution and is raised up from the solution, the surface spanning the wire is a soap film. What are the possible shapes of soap films and why? Or, for instance, why is DNA like a double spiral stair…

2002-08-23abs ↗pdf ↗

Model explains deleveraging risks in non-custodial stablecoins.

problem Deleveraging risks in non-custodial stablecoins during market crises.
method Developed a stochastic model incorporating speculators' profit optimization and collateral liquidation costs.
result Identified deflationary deleveraging spirals and higher price variance in unstable domains.

In this paper, we find all constant slope surfaces in the Euclidean 3-space, namely those surfaces for which the position vector of a point of the surface makes constant angle with the normal at the surface in that point. These surfaces could be thought as the bi-dimensional analogue of the generalized helices. Some pi…

2009-03-07abs ↗pdf ↗

Study loxodromes and geodesics on rotational surfaces in pseudo-isotropic space.

problem No study on loxodromes in pseudo-isotropic space I_p^3.
method Define pseudo-isotropic angles, derive equations for space-like and time-like loxodromes and geodesics on rotational surfaces.
result Equations for space-like and time-like loxodromes and geodesics on rotational surfaces in pseudo-isotropic space.