arXiv subjects

Matthias Schröder

Publications and source records attributed to Matthias Schröder.

10 recordsLinked to original sources

arXiv2025

Data Preservation in High Energy Physics

Data preservation significantly increases the scientific output of high-energy physics experiments during and after data acquisition. For new and ongoing experiments, the careful consideration of long-term data preservation in the experimental design contributes to improving computational efficiency and strengthening the scientific activity in HEP through Open Science methodologies. This contribution is based on 15 years of experience of the DPHEP collaboration in the field of data preservation and focuses on aspects relevant for the strategic programming of particle physics in Europe: the preparation of future programs using data sets preserved from previous similar experiments (e.g. HERA for EIC), and the use of LHC data long after the end of the data taking. The lessons learned from past collider experiments and recent developments open the way to a number of recommendations for the full exploitation of the investments made in large HEP experiments.

hep-ex↗

arXiv2020

Admissibly Represented Spaces and Qcb-Spaces

A basic concept of Type Two Theory of Effectivity (TTE) is the notion of an admissibly represented space. Admissibly represented spaces are closely related to qcb-spaces. The latter form a well-behaved subclass of topological spaces. We give a survey of basic facts about Type Two Theory of Effectivity, admissibly represented spaces, qcb-spaces and effective qcb-spaces. Moreover, we discuss the relationship of qcb-spaces to other categories relevant to Computable Analysis.

cs.LO↗

arXiv2019

Randomized Computation of Continuous Data: Is Brownian Motion Computable?

We consider randomized computation of continuous data in the sense of Computable Analysis. Our first contribution formally confirms that it is no loss of generality to take as sample space the Cantor space of infinite FAIR coin flips. This extends [Schröder&Simpson'05] and [Hoyrup&Rojas'09] considering sequences of suitably and adaptively BIASED coins. Our second contribution is concerned with 1D Brownian Motion (aka Wiener Process), a probability distribution on the space of continuous functions f:[0,1]->R with f(0)=0 whose computability has been conjectured [Davie&Fouché'13; arXiv:1409.4667,S6]. We establish that this (higher-type) random variable is computable iff some/every computable family of moduli of continuity (as ordinary random variables) has a computable probability distribution with respect to the Wiener Measure.

math.NA↗

arXiv2019

Overt choice

We introduce and study the notion of overt choice for countably-based spaces and for CoPolish spaces. Overt choice is the task of producing a point in a closed set specified by what open sets intersect it. We show that the question of whether overt choice is continuous for a given space is related to topological completeness notions such as the Choquet-property; and to whether variants of Michael's selection theorem hold for that space. For spaces where overt choice is discontinuous it is interesting to explore the resulting Weihrauch degrees, which in turn are related to whether or not the space is Frechet-Urysohn.

math.LO↗

arXiv2017

Bounded time computation on metric spaces and Banach spaces

We extend the framework by Kawamura and Cook for investigating computational complexity for operators occurring in analysis. This model is based on second-order complexity theory for functions on the Baire space, which is lifted to metric spaces by means of representations. Time is measured in terms of the length of the input encodings and the required output precision. We propose the notions of a complete representation and of a regular representation. We show that complete representations ensure that any computable function has a time bound. Regular representations generalize Kawamura and Cook's more restrictive notion of a second-order representation, while still guaranteeing fast computability of the length of the encodings. Applying these notions, we investigate the relationship between purely metric properties of a metric space and the existence of a representation such that the metric is computable within bounded time. We show that a bound on the running time of the metric can be straightforwardly translated into size bounds of compact subsets of the metric space. Conversely, for compact spaces and for Banach spaces we construct a family of admissible, complete, regular representations that allow for fast computation of the metric and provide short encodings. Here it is necessary to trade the time bound off against the length of encodings.

cs.LO↗

arXiv2016

Searches for $t\bar{t}H$ and $tH$ with $H\to b\bar b$

The associated production of a Higgs boson with a top quark-antiquark pair ($\text{t}\bar{\text{t}}\text{H}$ production) or with a single top quark ($\text{tH}$ production) allows a direct measurement of the top-Higgs-Yukawa coupling with minimal model dependence. In this article, recent results of searches for $\text{t}\bar{\text{t}}\text{H}$ and $\text{tH}$ production in the $\text{H}\rightarrow\text{b}\bar{\text{b}}$ channel performed by the ATLAS and CMS experiments are reviewed. The analyses use pp collision data collected at a centre-of-mass energy of 13$\,$TeV corresponding to an integrated luminosity of up to 13.2$\,$fb${}^{-1}$.

hep-ex↗

arXiv2016

Status Report of the DPHEP Collaboration: A Global Effort for Sustainable Data Preservation in High Energy Physics

Data from High Energy Physics (HEP) experiments are collected with significant financial and human effort and are mostly unique. An inter-experimental study group on HEP data preservation and long-term analysis was convened as a panel of the International Committee for Future Accelerators (ICFA). The group was formed by large collider-based experiments and investigated the technical and organizational aspects of HEP data preservation. An intermediate report was released in November 2009 addressing the general issues of data preservation in HEP and an extended blueprint paper was published in 2012. In July 2014 the DPHEP collaboration was formed as a result of the signature of the Collaboration Agreement by seven large funding agencies (others have since joined or are in the process of acquisition) and in June 2015 the first DPHEP Collaboration Workshop and Collaboration Board meeting took place. This status report of the DPHEP collaboration details the progress during the period from 2013 to 2015 inclusive.

hep-ex↗

arXiv2015

A Hofmann-Mislove Theorem for Scott open sets

We consider the intersection map on the family of non-empty $ω$-Scott-open sets of the lattice of opens of a topological space. We prove that in a certain class of topological spaces the intersection map forms a continuous retraction onto the space of countably compact subsets of the space equipped with (the sequentialisation of) the upper Vietoris topology. This class consists of all sequential spaces which are sequentially Hausdorff.

math.LO↗

arXiv2014

Hyperprojective Hierarchy of QCB_0-spaces

We extend the Luzin hierarchy of qcb$_0$-spaces introduced in [ScS13] to all countable ordinals, obtaining in this way the hyperprojective hierarchy of qcb$_0$-spaces. We generalize all main results of [ScS13] to this larger hierarchy. In particular, we extend the Kleene-Kreisel continuous functionals of finite types to the continuous functionals of countable types and relate them to the new hierarchy. We show that the category of hyperprojective qcb$_0$-spaces has much better closure properties than the category of projective qcb$_0$-space. As a result, there are natural examples of spaces that are hyperprojective but not projective.

cs.LO↗

arXiv2009

Data Preservation at LEP

The four LEP experiments ALEPH, DELPHI, L3 and OPAL successfully recorded e+e- collision data during the years 1989 to 2000. As part of the ordinary evolution in High Energy Physics, these experiments can not be repeated and their data is therefore unique. This article briefly reviews the data preservation efforts undertaken by the four experiments beyond the end of data taking. The current status of the preserved data and associated tools is summarised.

hep-ex↗