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The clockwork mechanism is a means of naturally generating exponential hierarchies in theories without significant hierarchies among fundamental parameters. We emphasize the role of interactions in the clockwork mechanism, demonstrating…

High Energy Physics - Phenomenology · Physics 2017-10-25 Nathaniel Craig , Isabel Garcia Garcia , Dave Sutherland

In the last ten years extraordinary results in time and frequency metrology have been demonstrated. Frequency-stabilization techniques for continuous-wave lasers and femto-second optical frequency combs have enabled a rapid development of…

Atomic Physics · Physics 2014-01-14 N. Poli , C. W. Oates , P. Gill , G. M. Tino

In neutral atom optical clocks, the higher-order atomic polarizability terms lead to the clock transition frequency shift which is motion-state dependent and nonlinear with the optical lattice depth. We propose to use an auxiliary optical…

Atomic Physics · Physics 2024-02-06 Artem Golovizin

Let $\Gamma=(V,E)$ be a finite simple graph. A matching $M \subseteq E$ is positive if there exists a weight function on $V$ such that the matching $M$ is characterized by those edges with positive weights. A positive matching decomposition…

Combinatorics · Mathematics 2025-02-06 Mohammad Farrokhi Derakhshandeh Ghouchan , Ali Akbar Yazdan Pour

A graph is Schur-positive if its chromatic symmetric function expands non-negatively in the Schur basis. We determine a full Schur-positivity classification for complete multipartite graphs by showing that a complete multipartite graph…

Combinatorics · Mathematics 2026-04-30 Ethan Shelburne , Stephanie van Willigenburg

We prove the Cone Theorem for algebraically integrable foliations. As a consequence, we show that termination of flips implies the b-nefness of the moduli part of a log canonical pair with respect to a contraction, generalising the case of…

Algebraic Geometry · Mathematics 2022-03-03 Florin Ambro , Paolo Cascini , Vyacheslav Shokurov , Calum Spicer

In this work, we define an orthogonal graph on the set of equivalence classes of $(2\nu + \delta)-$tuples over $\mathbb{Z}_{2^n}$ where $n$ and $\nu$ are positive integers and $\delta = 0, 1$ or $2$. We classify our graph if it is strongly…

Combinatorics · Mathematics 2019-01-07 Songpon Sriwongsa

For a graph $G$, let $\sigma_{2}(G)$ be the minimum degree sum of two non-adjacent vertices in $G$. A chord of a cycle in a graph $G$ is an edge of $G$ joining two non-consecutive vertices of the cycle. In this paper, we prove the following…

Combinatorics · Mathematics 2018-08-14 Shuya Chiba , Suyun Jiang , Jin Yan

The first part of the paper studies star-cycle factors of graphs. It characterizes star-cycle factors of a graph $G$ and proves upper bounds for the minimum number of $K_{1,2}$-components in a $\{K_{1,1}, K_{1,2}, C_n\colon n\ge 3\}$-factor…

Combinatorics · Mathematics 2021-01-12 Antje Klopp , Eckhard Steffen

This article revisits the historiography of the problem of inertial frames. Specifically, the case of the twins in the clock paradox is considered to see that some resolutions implicitly assume inertiality for the non-accelerating twin. If…

General Physics · Physics 2012-02-15 Subhash Kak

In trapped-atom clocks, the primary source of decoherence is often the phase noise of the oscillator. For this case, we derive theoretical performance gains by combining several atomic ensembles. For example, M ensembles of N atoms can be…

Quantum Physics · Physics 2013-11-15 T. Rosenband , D. R. Leibrandt

A matching $M$ in a graph $\Gamma$ is positive if $\Gamma$ has a vertex-labeling such that $M$ coincides with the set of edges with positive weights. A positive matching decomposition (pmd) of $\Gamma$ is an edge-partition $M_1,\ldots,M_p$…

Two celebrated conjectures in chromatic symmetric function theory concern the positivity chromatics symmetric functions of claw-free graphs. Here we extend the claw-free idea to general graphs and consider the e-positivity question for…

Combinatorics · Mathematics 2017-09-12 Angèle M. Hamel , Chính T. Hoàng , Jake E. Tuero

We interpret realizations of a graph on the sphere up to rotations as elements of a moduli space of curves of genus zero. We focus on those graphs that admit an assignment of edge lengths on the sphere resulting in a flexible object. Our…

Combinatorics · Mathematics 2022-05-25 Matteo Gallet , Georg Grasegger , Jan Legerský , Josef Schicho

We examine the relationships between axiomatic and cyclic proof systems for the partial and total versions of Hoare logic and those of its dual, known as reverse Hoare logic (or sometimes incorrectness logic). In the axiomatic proof systems…

Logic in Computer Science · Computer Science 2026-03-03 James Brotherston , Quang Loc Le , Gauri Desai , Yukihiro Oda

According to thermodynamics, the inevitable increase of entropy allows the past to be distinguished from the future. From this perspective, any clock must incorporate an irreversible process that allows this flow of entropy to be tracked.…

Quantum Physics · Physics 2021-03-18 Emanuel Schwarzhans , Maximilian P. E. Lock , Paul Erker , Nicolai Friis , Marcus Huber

A graph is called t-perfect if its stable set polytope is defined by non-negativity, edge and odd-cycle inequalities. We show that it can be decided in polynomial time whether a given claw-free graph is t-perfect.

Discrete Mathematics · Computer Science 2013-10-31 Henning Bruhn , Oliver Schaudt

In Stanley's seminal 1995 paper on the chromatic symmetric function, he stated that there was no known graph that was not contractible to the claw and whose chromatic symmetric function was not $e$-positive, namely, not a positive linear…

Combinatorics · Mathematics 2020-05-21 Samantha Dahlberg , Angele Foley , Stephanie van Willigenburg

In this paper we treat the so called clock paradox in an analytical way by assuming that a constant and uniform force F of finite magnitude acts continuously on the moving clock along the direction of its motion assumed to be rectilinear.…

Classical Physics · Physics 2007-05-23 Lorenzo Iorio

The possibility of detecting the gravitomagnetic clock effect using artificial Earth satellites provides the incentive to develop a more intuitive approach to its derivation. We first consider two test electric charges moving on the same…

General Relativity and Quantum Cosmology · Physics 2010-05-28 Lorenzo Iorio , Herbert I. M. Lichtenegger , Bahram Mashhoon