arXiv research

Paper proves Łojasiewicz inequalities near simple bubble trees on surfaces.

Study proves Lojasiewicz inequalities for harmonic maps near simple bubble trees.

Proves finite step termination of Kähler-Einstein metric singularity formation.

We construct a partial order relation which acts on the set of 3-cliques of a maximal planar graph G and defines a unique hierarchy. We demonstrate that G is the union of a set of special subgraphs, named `bubbles', that are themselves maximal planar graphs. The graph G is retrieved by connecting these bubbles in a tre…

Proves convergence of gradient Ricci shrinkers with uniform bounds.

Study on metric bubbles in complex dimensions 1 and 2.

In this paper, we study the weak compactness of the set of conformal metrics in any Riemann surface without boundary whose Calabi energy and area are uniformly bounded. We prove that for any sequence of such metrics, there alwasy exists a subsequence which converges in H\sp{2,2}_\sb{loc} everywhere except a finite numb…

Maps converge to simpler structures under certain tension conditions.

In this paper we develop a bubble tree structure for a degenerating class of Riemannian metrics satisfying some global conformal bounds on compact manifolds of dimension 4. Applying the bubble tree structure, we establish a gap theorem, a finiteness theorem for diffeomorphism type for this class, and a diameter bound f…

Study on prescribing positive curvature with conical singularities on a sphere.

Compactness theorem for quasiregular curves proves normality and resolves nodal points.

Gluing theorem for collapsing warped-QAC Calabi-Yau manifolds verified.

The paper develops a theory for free boundary minimal surfaces with genus at least one.

We investigate the Hawking energy of small surfaces in space times without symmetry assumptions by introducing the notion of Hawking type functionals. In particular, we find that Hawking type functionals are generalized Willmore functionals which allows us to find area constrained, minimizing, immersed, haunted bubble …

The paper proves a new method to find the maximum Laplace eigenvalues on surfaces.

Study on membranes under confinement, proving existence and regularity of minimizers.

The paper studies vector bundles over surfaces, focusing on singularity formation.

This paper proves compactness of conformal Chern-minimal surfaces in Hermitian surfaces.

The paper proves a Lojasiewicz inequality for maps from the 2-sphere to itself.

We determine bubble tree convergence for a sequence of harmonic maps, with uniform energy bounds, from a compact Riemann surface into a compact locally CAT(1) space. In particular, we demonstrate energy quantization and the no-neck property for such a sequence. In the smooth setting, Jost and Parker respectively establ…

Two-cycle GEILA equilibria are OLG equilibria and vice versa, with applications to indeterminacy and bubbles.

We discuss - in what is intended to be a pedagogical fashion - a criterion, which is a lower bound on a certain ratio, for when a stock (or a similar instrument) is not a good investment in the long term, which can happen even if the expected return is positive. The root cause is that prices are positive and have skewe…

We develop a bubble tree construction and prove compactness results for $W^{2,2}$ branched conformal immersions of closed Riemann surfaces, with varying conformal structures whose limit may degenerate, in a compact Riemannian manifold with uniformly bounded areas and Willmore energies. The compactness property is appli…

We study a class of weakly conformal $3$-harmonic maps, called associative Smith maps, from $3$-manifolds into $7$-manifolds that parametrize associative $3$-folds in Riemannian $7$-manifolds equipped with $\mathrm{G}_2$-structures. Associative Smith maps are solutions of a conformally invariant nonlinear first order P…

We quantify the amount of information filtered by different hierarchical clustering methods on correlations between stock returns comparing it with the underlying industrial activity structure. Specifically, we apply, for the first time to financial data, a novel hierarchical clustering approach, the Directed Bubble Hi…

We prove a bubble tree convergence theorem for a sequence of closed Hamiltonian Stationary Lagrangian surfaces with bounded areas and Willmore energies in a complete K{ä}hler surface. We also prove two strong compactness theorems on the space of Hamiltonian stationary Lagrangian tori in $\mathbb C^2$ and $\mathbb{CP}^2…

Let $(M; g)$ be a smooth compact Riemiannian manifold without boundary and $g_{k}$ be a metric conformal to $g$. Suppose $vol(M; g_{k})+||R_{k}||_{L^{p}(M;g_{k})} < C$, where $R_{k}$ is the scalar curvature and $p > \frac{n}{2}$. We will use the 3-circle theorem and the John-Nirenberg inequality to study the bubble tre…

Study of critical points in Ginzburg-Landau approximation with stability results.

Technical trading rules and linear regressive models are often used by practitioners to find trends in financial data. However, these models are unsuited to find non-linearly separable patterns. We propose a decision tree forecasting model that has the flexibility to capture arbitrary patterns. To illustrate, we constr…

Study fragility in global financial indices using network analysis.

Harmonic map flow's singularity properties proven with Lojasiewicz inequalities.

Characterizes critical points in convex double and triple bubbles.

We introduce a notion of generalized Willmore functionals motivated by the Hawking energy of General Relativity and bending energies of membranes. An example of a bending energy is discussed in detail. Using results of Y. Chen and J. Li, we present a compactness result for branched, immersed, haunted, stratified surfac…

Survey on soap bubble partitions and their stability.

Bubbles are essential in certain economic models with high growth and low interest rates.

Study Yang-Mills connections on four-manifolds, derive obstructions to bubbling.

Rational bubbles form in nonstationary models of real assets.

Existence of double bubbles with high constant mean curvatures in Riemannian manifolds.

Defines speculative bubbles in discrete-time models based on discounted stock price losing mass.

Degenerate solutions found in 2D H-system bubbles with higher degrees.

This is the third installment of the Financial Bubble Experiment. Here we provide the digital fingerprint of an electronic document in which we identify 27 bubbles in 27 different global assets; for 25 of these assets, we present windows of dates of the most likely ending time of each bubble. We will provide that docum…

On 2 November 2009, the Financial Bubble Experiment was launched within the Financial Crisis Observatory (FCO) at ETH Zurich (\url{http://www.er.ethz.ch/fco/}). In that initial report, we diagnosed and announced three bubbles on three different assets. In this latest release of 23 December 2009 in this ongoing experime…

Continuous time analysis of bubble formation in harmonic maps.

Trading bubbles form when traders adapt to price mismatches.

This is the second installment of the Financial Bubble Experiment. Here we provide the digital fingerprint of an electronic document in which we identify 7 bubbles in 7 different global assets; for 4 of these assets, we present windows of dates of the most likely ending time of each bubble. We will provide that documen…

Solves the quintuple bubble problem on spheres and Euclidean spaces.

Using a recently introduced rational expectation model of bubbles, based on the interplay between stochasticity and positive feedbacks of prices on returns and volatility, we develop a new methodology to test how this model classifies 9 time series that have been previously considered as bubbles ending in crashes. The …

Paper evaluates whether AI is a bubble or a productivity revolution.