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We compute the three point correlation functions for primordial scalar and tensor fluctuations in single field inflationary models. We obtain explicit expressions in the slow roll limit where the answer is given terms of the two usual slow…

Astrophysics · Physics 2009-11-07 Juan Maldacena

We prove that a weak $\mathbb{Q}$-Fano $3$-fold with terminal singularities has unobstructed deformations. By using this result and computing some invariants of a terminal singularity, we provide two results on global deformation of a weak…

Algebraic Geometry · Mathematics 2017-09-12 Taro Sano

We introduce an inertial variant of the forward-Douglas-Rachford splitting and analyze its convergence. We specify an instance of the proposed method to the three-composite convex minimization template. We provide practical guidance on the…

Optimization and Control · Mathematics 2019-05-01 Volkan Cevher , Bang Cong Vu , Alp Yurtsever

We completely prove the ACC for minimal log discrepancies on smooth threefolds. It implies on smooth threefolds the ACC for a-lc thresholds, the uniform m-adic semi-continuity of minimal log discrepancies and the boundedness of the log…

Algebraic Geometry · Mathematics 2023-12-29 Masayuki Kawakita

We discuss some surprising phenomena from basic calculus related to oscillating functions and to the theorem on the differentiability of inverse functions. Among other things, we see that a continuously differentiable function with a strict…

History and Overview · Mathematics 2016-09-29 Juergen Grahl , Shahar Nevo

We show that in any sequence of a general type MMP, the minimal log discrepancy of singularities takes at most finitely many values, and the fibers of all the extremal contractions and flips belong to a bounded family. A key ingredient in…

Algebraic Geometry · Mathematics 2025-09-03 Jingjun Han , Lu Qi , Ziquan Zhuang

Let $M$ be a triangulated, oriented, connected compact $3$-manifold with connected non-empty boundary. Such a manifold admits a unique decomposition into $\triangle$-prime $3$-manifolds. In this paper, we show that the adjoint Reidemeister…

Geometric Topology · Mathematics 2022-05-10 Esma Dirican Erdal

Let X be a projective variety with terminal singularities and let L be an ample Cartier divisor on X. We prove that if f is a birational contraction associated to an extremal ray $ R \subset \bar {NE(X)}$ such that R.(K_X+(n-2)L)<0, then f…

Algebraic Geometry · Mathematics 2018-05-16 Marco Andreatta , Luca Tasin

In this paper we consider the flip operation for combinatorial pointed pseudo-triangulations where faces have size 3 or 4, so-called combinatorial 4-PPTs. We show that every combinatorial 4-PPT is stretchable to a geometric…

Combinatorics · Mathematics 2020-07-21 Oswin Aichholzer , Thomas Hackl , David Orden , Alexander Pilz , Maria Saumell , Birgit Vogtenhuber

Given a factorable function f, we propose a procedure that constructs a concave underestimator of f that is tight at a given point. These underestimators can be used to generate intersection cuts. A peculiarity of these underestimators is…

Optimization and Control · Mathematics 2018-12-10 Felipe Serrano

Following the first paper, we continue to study Mori extractions from singular curves centred in a smooth 3-fold. We treat the case where the divisorial extraction exists in relative codimension at most 3.

Algebraic Geometry · Mathematics 2016-09-09 Tom Ducat

Let $G$ be a connected algebraic group. We study $G$-equivariant extremal contractions whose centre is a codimension three $G$-simply connected orbit. In the spirit of an important result by Kawakita in 2001, we prove that those…

Algebraic Geometry · Mathematics 2024-10-02 Samuel Boissière , Enrica Floris

We prove that for a given flat surface with conical singularities, any pair of geometric triangulations can be connected by a chain of flips.

Geometric Topology · Mathematics 2019-07-03 Guillaume Tahar

We show that the triangulations of a finite point set form a flip graph that can be embedded isometrically into a hypercube, if and only if the point set has no empty convex pentagon. Point sets of this type include convex subsets of…

Computational Geometry · Computer Science 2016-08-12 David Eppstein

We show that $O(n^2)$ exchanging flips suffice to transform any edge-labelled pointed pseudo-triangulation into any other with the same set of labels. By using insertion, deletion and exchanging flips, we can transform any edge-labelled…

Computational Geometry · Computer Science 2015-12-07 Prosenjit Bose , Sander Verdonschot

Some fixed point results are given for a class of functional contractions over partial metric spaces. These extend some contributions in the area due to Ilic et al [Math. Comput. Modelling, 55 (2012), 801-809].

General Topology · Mathematics 2012-03-27 Mihai Turinici

For $\mathbb Q$-factorial klt algebraically integrable adjoint foliated structures, we prove the cone theorem, the contraction theorem, and the existence of flips. Therefore, we deduce the existence of the minimal model program for such…

Algebraic Geometry · Mathematics 2024-08-27 Paolo Cascini , Jingjun Han , Jihao Liu , Fanjun Meng , Calum Spicer , Roberto Svaldi , Lingyao Xie

We introduce a new approach to an enumerative problem closely linked with the geometry of branched coverings; that is, we study the number of ways a permutation can be decomposed into a product of a given number of 2-cycles, 3-cycles, etc.…

Combinatorics · Mathematics 2007-05-23 John Irving

For a birational log Fano contraction, it is conjectured an inequality between the dimension of its exceptional locus and the minimal log discrepancy over the locus. The conjecture follows from the existence of the flip for the contraction…

Algebraic Geometry · Mathematics 2016-09-07 V. V. Shokurov

In this paper, we define the recurrence and "non-wandering" for decompositions. The following inclusion relations hold for codimension one foliations on closed $3$-manifolds: $\{$minimal$\} \sqcup \{$compact$\}$ $\subsetneq$ $\{$pointwise…

Dynamical Systems · Mathematics 2017-07-18 Tomoo Yokoyama