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Without imposing restrictions on a weighted graph's arc lengths, symmetry structures cannot be expected. But, they exist. To find them, the graphs are decomposed into a component that dictates all closed path properties (e.g., shortest and…

Combinatorics · Mathematics 2022-04-27 Donald Saari

It is challenging task to detect and measure genuine multipartite entanglement. We investigate the problem by considering the average based positive partial transposition(PPT) criterion and the realignment criterion. Sufficient conditions…

Quantum Physics · Physics 2017-12-19 Ming Li , Jing Wang , Shuqian Shen , Zhihua Chen , Shao-Ming Fei

In this paper we describe a new connection between UPB (unextendable product bases) and P (positive) maps which are not CP (completely positive). We show that inner automorphisms of the set of P maps which are not CP, produce extremal…

Quantum Physics · Physics 2014-08-06 R. Sengupta , Arvind

Let $\lpt(G)$ be the minimum cardinality of a set of vertices that intersects all longest paths in a graph $G$. Let $\omega(G)$ be the size of a maximum clique in $G$, and $\tw(G)$ be the treewidth of $G$. We prove that $ \lpt(G) \leq…

Discrete Mathematics · Computer Science 2017-12-20 Márcia R. Cerioli , Cristina G. Fernandes , Renzo Gómez , Juan Gutiérrez , Paloma T. Lima

The study of the entanglement entropy and entanglement spectrum has proven to be very fruitful in identifying topological phases of matter. Typically, one performs numerical studies of finite-size systems. However, there are few rigorous…

Strongly Correlated Electrons · Physics 2015-09-29 B. Majidzadeh Garjani , B. Estienne , E. Ardonne

Two graph parameters are said to be coarsely equivalent if they are within constant factors from each other for every graph $G$. Recently, several graph parameters were shown to be coarsely equivalent to tree-length. Recall that the length…

Combinatorics · Mathematics 2025-04-02 Feodor F. Dragan , Ekkehard Köhler

Structure in quantum entanglement entropy is often leveraged to focus on a small corner of the exponentially large Hilbert space and efficiently parameterize the problem of finding ground states. A typical example is the use of matrix…

Statistical Mechanics · Physics 2023-04-17 Bart Olsthoorn

Let $P_{n}$ be a set of $n$ points, including the origin, in the unit square $U = [0,1]^2$. We consider the problem of constructing $n$ axis-parallel and mutually disjoint rectangles inside $U$ such that the bottom-left corner of each…

Discrete Mathematics · Computer Science 2014-04-29 Sandip Banerjee , Aritra Banik , Bhargab B. Bhattacharya , Arijit Bishnu , Soumyottam Chatterjee

Persistent homology (PH) has been widely applied to graph data to extract topological features. However, little attention has been paid to how different distance functions on a graph affect the resulting persistence barcodes and their…

Algebraic Topology · Mathematics 2026-02-17 Eunwoo Heo , Byeongchan Choi , Jae-Hun Jung

A merge tree is a fundamental topological structure used to capture the sub-level set (and similarly, super-level set) topology in scalar data analysis. The interleaving distance is a theoretically sound, stable metric for comparing merge…

Computational Geometry · Computer Science 2026-02-13 Althaf P , Amit Chattopadhyay , Osamu Saeki

Quantum entanglement is an important phenomenon in quantum information theory. To detect entanglement theoretically, positive but not completely positive maps are used. The Kadison-Schwarz (KS) inequality interpolates between positivity and…

Quantum Physics · Physics 2025-09-23 Hajir Al Zadjali , Farrukh Mukhamedov

A $triangulation$ is an embedding of a graph on surfaces where every face has length three. In this article, we show the existence of contractible Hamiltonian cycle in triangulated maps of which minimum degree is four.

Combinatorics · Mathematics 2014-07-14 Dipendu Maity , Ashish Kumar Upadhyay

The density matrix of composite spin system is discussed in relation to the adjoint representation of unitary group U(n). The entanglement structure is introduced as an additional ingredient to the description of the linear space carrying…

Quantum Physics · Physics 2007-05-23 V. I. Man'ko , G. Marmo , E. C. G. Sudarshan , F. Zaccaria

Important data mining problems such as nearest-neighbor search and clustering admit theoretical guarantees when restricted to objects embedded in a metric space. Graphs are ubiquitous, and clustering and classification over graphs arise in…

Combinatorics · Mathematics 2018-01-16 Jose Bento , Stratis Ioannidis

We investigate the quantum nature of gravity in terms of the coherence of quantum objects. As a basic setting, we consider two gravitating objects each in a superposition state of two paths. The evolution of objects is described by the…

Quantum Physics · Physics 2022-10-12 Akira Matsumura

We consider the problem of achieving average consensus in the minimum number of linear iterations on a fixed, undirected graph. We are motivated by the task of deriving lower bounds for consensus protocols and by the so-called "definitive…

Optimization and Control · Mathematics 2013-08-30 Julien M. Hendrickx , Raphaël M. Jungers , Alexander Olshevsky , Guillaume Vankeerberghen

Map matching is a common task when analysing GPS tracks, such as vehicle trajectories. The goal is to match a recorded noisy polygonal curve to a path on the map, usually represented as a geometric graph. The Fr\'echet distance is a…

Computational Geometry · Computer Science 2024-07-30 Kevin Buchin , Maike Buchin , Joachim Gudmundsson , Aleksandr Popov , Sampson Wong

We prove a multiplicative ergodic theorem for bistochastic completely positive (bcp) linear cocycles acting on finite-dimensional matrix algebras, giving an invariant splitting described explicitly in terms of the multiplicative domains of…

Quantum Physics · Physics 2025-11-17 Owen Ekblad

A consistent path system in a graph $G$ is an collection of paths, with exactly one path between any two vertices in $G$. A path system is said to be consistent if it is intersection-closed. We say that $G$ is strictly metrizable if every…

Combinatorics · Mathematics 2025-01-24 Maria Chudnovsky , Daniel Cizma , Nati Linial

We investigate the structure of $k$-positivity and Schmidt numbers for classes of linear maps and bipartite quantum states exhibiting symplectic group symmetries. Specifically, we consider (1) linear maps on $M_d(\mathbb{C})$ which are…

Quantum Physics · Physics 2026-03-11 Sang-Jun Park
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