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Related papers: CAT(0) is an algorithmic property

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We present an algorithm which takes as input a closed semi-algebraic set, $S \subset \R^k$, defined by \[ P_1 \leq 0, ..., P_\ell \leq 0, P_i \in \R[X_1,...,X_k], \deg(P_i) \leq 2, \] and computes the Euler-Poincar\'e characteristic of $S$.…

Symbolic Computation · Computer Science 2007-05-23 Saugata Basu

It is proved that any polynomial vector field in two complex variables which is complete on a non-algebraic trajectory is complete.

Complex Variables · Mathematics 2014-09-03 Alvaro Bustinduy , Luis Giraldo

We provide examples of non-locally compact geodesic Ptolemy metric spaces which are not uniquely geodesic. On the other hand, we show that locally compact, geodesic Ptolemy metric spaces are uniquely geodesic. Moreover, we prove that a…

Metric Geometry · Mathematics 2007-05-23 Thomas Foertsch , Alexander Lytchak , Viktor Schroeder

We provide a systematic description of the automorphism groups of specially cocompact CAT(0) cube complexes. We show that these groups are topologically finitely generated, present a method to explicitly obtain generating sets, and prove a…

Group Theory · Mathematics 2023-12-07 Tobias Hartnick , Merlin Incerti-Medici

We construct quantum algorithms to compute physical observables of nonlinear PDEs with M initial data. Based on an exact mapping between nonlinear and linear PDEs using the level set method, these new quantum algorithms for nonlinear…

Quantum Physics · Physics 2025-04-22 Shi Jin , Nana Liu

We present an efficient quantum algorithm for some independent set problems in graph theory, based on non-abelian adiabatic mixing. We illustrate the performance of our algorithm with analysis and numerical calculations for two different…

Quantum Physics · Physics 2020-01-22 Biao Wu , Hongye Yu , Frank Wilczek

Quantum computation with quantum data that can traverse closed timelike curves represents a new physical model of computation. We argue that a model of quantum computation in the presence of closed timelike curves can be formulated which…

Quantum Physics · Physics 2008-11-26 Dave Bacon

With the advent of ultra-high power lasers the nonlinear nature of the vacuum of quantum electrodynamics (QED) can be probed. Due to the highly nonlinear structure of the underlying equations new numerical algorithms are required. A…

Computational Physics · Physics 2017-09-27 Arnau Pons Domenech , Hartmut Ruhl

Nonlinear equations are challenging to solve due to their inherently nonlinear nature. As analytical solutions typically do not exist, numerical methods have been developed to tackle their solutions. In this article, we give a quantum…

Quantum Physics · Physics 2025-11-04 Nhat A. Nghiem , Tzu-Chieh Wei

We explain why semistability of a one-ended proper CAT(0) space can be determined by the geodesic rays. This is applied to boundaries of CAT(0) groups.

Group Theory · Mathematics 2017-03-22 Ross Geoghegan

The concept of open weak CAD is introduced. Every open CAD is an open weak CAD. On the contrary, an open weak CAD is not necessarily an open CAD. An algorithm for computing projection polynomials of open weak CADs is proposed. The key idea…

Symbolic Computation · Computer Science 2019-03-28 Jingjun Han , Liyun Dai , Hoon Hong , Bican Xia

Attempts to separate the power of classical and quantum models of computation have a long history. The ultimate goal is to find exponential separations for computational problems. However, such separations do not come a dime a dozen: while…

Quantum Physics · Physics 2013-12-05 Martin Roetteler

There have been some effective tools for solving (constant/parametric) semi-algebraic systems in Maple's library RegularChains since Maple 13. By using the functions of the library, e.g., RealRootClassfication, one can prove and discover…

Symbolic Computation · Computer Science 2013-06-19 Lu Yang , Bican Xia

Most problems in uncertainty quantification, despite its ubiquitousness in scientific computing, applied mathematics and data science, remain formidable on a classical computer. For uncertainties that arise in partial differential equations…

Quantum Physics · Physics 2022-09-29 Francois Golse , Shi Jin , Nana Liu

We consider geodesically convex optimization problems involving distances to a finite set of points $A$ in a CAT(0) cubical complex. Examples include the minimum enclosing ball problem, the weighted mean and median problems, and the…

Optimization and Control · Mathematics 2024-05-06 Ariel Goodwin , Adrian S. Lewis , Genaro Lopez-Acedo , Adriana Nicolae

We calculate the zeros of an exponential polynomial of some variables by a classical algorithm and quantum algorithms which are based on the method of van Dam and Shparlinski, they treated the case of two variables, and compare with the…

Quantum Physics · Physics 2009-08-13 Yoshitaka Sasaki

We study classical query algorithms with post-selection, and find that they are closely connected to rational functions with nonnegative coefficients. We show that the post-selected classical query complexity of a Boolean function is equal…

Computational Complexity · Computer Science 2018-05-15 Chris Cade

An elementary application of Algorithmic Complexity Theory to the polygonal approximations of curved billiards-integrable and chaotic-unveils the equivalence of this problem to the procedure of quantization of classical systems: the scaling…

chao-dyn · Physics 2009-10-31 Giorgio Mantica

Answering connectivity queries in semi-algebraic sets is a long-standing and challenging computational issue with applications in robotics, in particular for the analysis of kinematic singularities. One task there is to compute the number…

Symbolic Computation · Computer Science 2020-09-01 Jose Capco , Mohab Safey El Din , Josef Schicho

The formula-evaluation problem is defined recursively. A formula's evaluation is the evaluation of a gate, the inputs of which are themselves independent formulas. Despite this pure recursive structure, the problem is combinatorially…

Quantum Physics · Physics 2009-07-10 Ben W. Reichardt