The paper studies Kähler-Ricci flow on Fano manifolds and finds examples of type II singularities.
problem Analyzing the behavior of Kähler-Ricci flow on Fano manifolds.
method Proving the flow is of type II and finding specific examples.
result Found examples of Fano compactifications where Kähler-Ricci flow develops type II singularities.
Study on Yamabe flow convergence and singularities.
problem Understanding convergence and singularities in Yamabe flow solutions.
method Analysis of complete non-compact conformally flat solutions to the Yamabe flow.
result Existence of Type II singularities that develop either at a finite time or as to+∞. The paper proves rigidity theorems for Type II singularities in Lagrangian flows.
problem Understanding Type II singularities in Lagrangian flows with zero Maslov class.
method Rigidity theorems for blow-up limits of Type II singularities.
result Generalized previous results from 2D to arbitrary dimensions.
Study shows how solutions to Yamabe flow can develop Type II singularities.
problem Existence and detailed analysis of Type II singularities in Yamabe flow.
method Detailed asymptotic analysis and blow-up rate calculation.
result Yamabe flow solutions can converge to a steady soliton after blow-up.
Strict type-II blowup in harmonic map flow is proven to have Hölder continuous body map.
problem Finite-time singularity of harmonic map flow.
method Analysis of outer energy scale and Hölder continuity proof.
result Strictly type-II blowup body map is Hölder continuous.
Kähler-Ricci flow shows type II singularity on Fano threefolds.
problem Understanding the behavior of Kähler-Ricci flow on Fano threefolds.
method Analyzing the Kähler-Ricci flow on Fano threefolds from a specific family.
result Kähler-Ricci flow develops type II singularity on Fano threefolds from the specified family.
In this paper we prove the existence of Type II singularities for the Ricci flow on Sn+1 for all n≥2.
Study of Lagrangian mean curvature flow with equivariant symmetry.
problem Understanding singularities in Lagrangian mean curvature flow.
method Structural theorems about blowups of finite-time singularities.
result Classification of singularities in equivariant case.
In this paper we investigate the singularities of Lagrangian mean curvature flows in Cm by means of smooth singularity models. Type I singularities can only occur at certain times determined by invariants in the cohomology of the initial data. In the type II case, these smooth singularity models are asympto…
Numerical simulations show stability of Type-II singularities in noncompact hypersurfaces.
problem Stability of Type-II singularities in noncompact hypersurfaces with rotationally-symmetric perturbations.
method Adaptation of the overlap method to include angular dependence.
result MCF of noncompact hypersurfaces with angular dependence behaves similarly to rotationally-symmetric perturbations, developing Type-II or Type-I singularities.
In previous work, Angenent, Isenberg, and Knopf created type-II Ricci flow neckpinch singularities. In this paper we construct solutions to Ricci flow whose initial data is the singular metric resulting from these singularities. We show in particular that the curvature decreases at the same rate at which it blew up. Th…
In this paper we prove that a certain class of embedded unknotted curves in R3 evolving under curve shortening flow do not form singularities Type II before collapsing to a point. Our proof uses tools of the minimal surface theory to study a suitable isoperimetric ratio.
Lagrangian spheres develop singularities under flow, matching Whitney spheres.
problem Understanding singularities in Lagrangian mean curvature flow.
method Analyzing equivariant Lagrangian spheres with Ricci curvature conditions.
result Whitney spheres develop type-II singularities rescaling to a grim reaper and flat subspace.
Constructs finite-time singularities in Lagrangian mean curvature flow with precise dynamics.
problem Finite-time singularities in Lagrangian mean curvature flow.
method Modulation analysis around shrinking cohomogeneity-one special Lagrangian desingularizations.
result Explicit curvature blow-up rate and precise dynamics of singularities.
Ricci flow shows Eguchi-Hanson singularities in 4D.
problem Modeling Ricci flow singularities on Eguchi-Hanson space.
method Proving singularity development and blow-up limits.
result Only specific blow-up limits for U(2)-invariant flows.
The paper examines translating solitons and their relation to Lagrangian mean curvature flows with zero Maslov class.
problem Understanding the behavior of Lagrangian translating solitons near Type II singularities.
method Analyzes necessary conditions for blow-up limits and applies to open questions.
result Provides a necessary condition for blow-up limits of Lagrangian mean curvature flows with zero Maslov class.
Classifies certain 3D knots with specific properties.
problem Classifying knots with specific clasp numbers and properties.
method Examined knots with clasp number 2 and genus 2 fibered, using clasp disks of type II.
result Found a partial classification of these knots.
T-duality in singular spacetime models with H-flux.
problem T-duality in singular spacetime models with H-flux.
method Initiate study of twisted equivariant Courant algebroids and apply to string theory.
result Ramond-Ramond charges classified by twisted equivariant cohomology groups.
Study Ricci flow on R^4 starting at a specific metric, finding singularities and minimal spheres.
problem Analyzing Ricci flow on R4 starting from a specific metric. method Ricci flow on R4, focusing on metrics with no necks and bounded by a cylinder. result The flow develops a global Type-II singularity and converges to the Bryant soliton.
We show that a rescale limit at any degenerate singularity of Ricci flow in dimension 3 is a steady gradient soliton. In particular, we give a geometric description of type I and type II singularities.
Study of curve shortening flow for twisted curves, defining curvature-torsion entropy.
problem Understanding the behavior of curves with curvature and torsion under curve shortening flow.
method Defined curvature-torsion entropy to analyze the flow of twisted curves.
result Curved curves under curve shortening flow either develop inflection points or exhibit highly irregular singularities.
We present an explicit formula for the topology and H-flux of the T-dual of a general type II compactification, significantly generalizing earlier results. Our results apply to T-dualities with respect to any circle action on spacetime. As before, T-duality exchanges type IIA and type IIB string theories. A new consequ…
Curve Shortening Flow preserves circularity for convex projections.
problem Understanding the behavior of curves under Curve Shortening Flow.
method Contradiction argument and analysis of tangent flows.
result Smooth curves with convex projections become asymptotically circular under Curve Shortening Flow.
Study magnetic fields on special Lie groups, proving non-existence of certain types.
problem Existence of closed 2-forms with specific properties on non-singular 2-step nilpotent Lie groups.
method Analyzing left-invariant magnetic fields on 2-step nilpotent Lie groups, proving non-existence and existence results.
result Strong obstruction and non-existence of closed 2-forms of type II on non-singular Lie algebras.
Local singularity analysis for Ricci flows with applications to bounded scalar curvature.
problem Understanding the nature of singularities in Ricci flows.
method Local singularity analysis, introducing Type I and Type II singular points, and proving curvature blow-up rates.
result Ricci curvature must blow up at least at a Type I rate near singular points of a Ricci flow.
Study shows instability of specific cone solutions in high-dimensional spaces.
problem Unstable solutions of minimal graphs in high codimension.
method Min-max technique applied to Euclidean spaces.
result First examples of non-smooth unstable minimal graphs.
We provide a condition for spatial curves which rules out the development of a type I singularity. The condition is that after the last time for which an inflection point develops, if the torsion is ever everywhere non-negative, the curve cannot develop a type I singularity.
In this paper, we study curvature behavior at the first singular time of solution to the Ricci flow on a smooth, compact n-dimensional Riemannian manifold M, ∂t∂gij=−2Rij for t∈[0,T). If the flow has uniformly bounded scalar curvature and develops Type I singularities at T, us…
Study Ricci flow on Rn+1, focusing on asymptotic behavior and singularities.
problem Analyzing the behavior of Ricci flow on Rn+1, especially near singularities. method Examined the flow starting from rotationally symmetric metrics, considering asymptotic curvature and pinched necks.
result Proved the existence of Type-II and Type-I singularities under specific conditions.
In this paper, we introduce a monotonicity formula for the mean curvature flow. We also apply this monotonicity formula to study the asymptotic behavior of eternal solutions.
In this paper we mainly study the type II singularities of the mean curvature flow from a symplectic surface or from an almost calibrated Lagrangian surface in a K ähler-Einstein surface. We show the relation between the maximum of the Kähler angle and the maximum of ∣H∣2 on the limit flow.
We consider the Kaehler-Ricci flow on complete finite-volume metrics that live on the complement of a divisor in a compact Kaehler manifold X. Assuming certain spatial asymptotics on the initial metric, we compute the singularity time in terms of cohomological data on X. We also give a sufficient condition for the sing…
Study shows different behaviors of noncompact hypersurfaces under mean curvature flow.
problem Analyzing stability of noncompact hypersurfaces with curvature blowup.
method Numerical overlap method to construct global solutions.
result Existence of near and far classes of initial data leading to distinct behaviors.
In earlier work, we derived formal matched asymptotic profiles for families of Ricci flow solutions developing Type-II degenerate neckpinches. In the present work, we prove that there do exist Ricci flow solutions that develop singularities modeled on each such profile. In particular, we show that for each positive int…
We consider the mean curvature evolution of rotationally symmetric surfaces. Using numerical methods, we detect critical behavior at the threshold of singularity formation resembling the one of gravitational collapse. In particular, the mean curvature simulation of a one-parameter family of initial data reveals the exi…
Study cohomogeneity-one Lagrangian mean curvature flow in complex spaces.
problem Analyzing mean curvature flow of Lagrangians in complex spaces with specific group actions.
method Classifying solutions and singularities of cohomogeneity-one Lagrangian mean curvature flow.
result Explicit examples of new solitons and singularity models.
We consider the initial value problem ut=Δlogu, u(x,0)=u0(x)≥0 in R2, corresponding to the Ricci flow, namely conformal evolution of the metric u(dx12+dx22) by Ricci curvature. It is well known that the maximal (complete) solution u vanishes identically after time $T= \frac 1{4π} \int_{\R^…
Researchers explore mirror symmetries for twisted G2 manifolds.
problem Exploring mirror symmetries for compactified Type II superstrings on G2 manifolds. method Revisits construction, discusses autoequivalence and duality, clarifies B-field role, tests conjectures against Joyce orbifold examples.
result Evidence for generalized mirror symmetries and massless spectra respectivity.
Gu and Zhu have shown that Type-II Ricci flow singularities develop from nongeneric rotationally symmetric Riemannian metrics on Sm, for all m≥3. In this paper, we describe and provide plausibility arguments for a detailed asymptotic profile and rate of curvature blow-up that we predict such solutions exhibit.
Study on curve shortening flow with Neumann boundary conditions, showing singularities and limits.
problem Analyzing singularities in curve shortening flow with Neumann boundary conditions.
method Criterion for initial curves leading to singularities, proof of singularity type, rescaling analysis.
result Existence of type II singularities and limit shapes for convex initial curves.
Ricci flow on warped products leads to curvature blow-up.
problem Behavior of Ricci flow on warped product metrics.
method Rigorous construction of conical singularities.
result Curvature blows up at a rate proportional to (T−t)−k. In each dimension N≥3 and for each real number λ≥1, we construct a family of complete rotationally symmetric solutions to Ricci flow on RN which encounter a global singularity at a finite time T. The singularity forms arbitrarily slowly with the curvature blowing up arbitrarily fast at the r…
The study bounds entropy of plane curves and applies to curve shortening flow.
problem Entropy bounds for plane curves and dynamics of CSF.
method Proving entropy lower and upper bounds, constructing curves.
result Entropy of curves is tightly bounded and applied to CSF.
Classifies K-stable Fano varieties and finds new examples.
problem Classifying K-stable Fano varieties and their properties.
method Classification and analysis of Gorenstein Fano bi-equivariant compactifications.
result Several explicit examples of K-stable Fano varieties and their properties.
Paper proves uniqueness of Type II Yamabe metrics on manifolds.
problem Uniqueness of Type II Yamabe metrics on compact manifolds.
method Investigates sufficient conditions for metric uniqueness and proves corresponding theorems.
result Establishes sufficient condition for a metric to be the unique Type II Yamabe metric.
Study curve shortening flow in high dimensions with boundary constraints.
problem Understanding the behavior of curves in high-dimensional spaces with boundary conditions.
method Used curvature and higher-derivative estimates, Stahl-type maximum principle, and blow-up analysis.
result Flow converges to a shrinking semicircle model or has only semicircle boundary singularities in low entropy regimes.
We use the twistorial construction of D-instantons in Calabi-Yau compactifications of type II string theory to compute an explicit expression for the metric on the hypermultiplet moduli space affected by these non-perturbative corrections. In this way we obtain an exact quaternion-Kahler metric which is a non-trivial d…
Compact mean curvature flow solutions with bounded curvature in high dimensions are constructed.
problem Constructing compact mean curvature flow solutions with bounded mean curvature.
method Following Velázquez, Guo, Sesum, and Stolarski's arguments, constructing solutions in \(\mathbb{R}^n\) with \(n \geq 8\).
result Compact mean curvature flow solutions with bounded mean curvature in \(\mathbb{R}^n\) are constructed.