Concept

Scalar boson

A scalar boson is a boson whose spin equals zero. A boson is a particle whose wave function is symmetric under particle exchange and therefore follows Bose–Einstein statistics. The spin–statistics theorem implies that all bosons have an integer-valued spin. Scalar bosons are the subset of bosons with zero-valued spin. The name scalar boson arises from quantum field theory, which demands that fields of spin-zero particles transform like a scalar under Lorentz transformation (i.e. are Lorentz invariant). A pseudoscalar boson is a scalar boson that has odd parity, whereas "regular" scalar bosons have even parity. The only fundamental scalar boson in the Standard Model of particle physics is the Higgs boson, the existence of which was confirmed on 14 March 2013 at the Large Hadron Collider by CMS and ATLAS. As a result of this confirmation, the 2013 Nobel Prize in physics was awarded to Peter Higgs and François Englert. Various known composite particles are scalar bosons, e.g. the alpha particle and scalar mesons. The φ4-theory or quartic interaction is a popular "toy model" quantum field theory that uses scalar bosonic fields, used in many introductory quantum textbooks to introduce basic concepts in field theory. There are no fundamental pseudoscalars in the Standard Model, but there are pseudoscalar mesons, like the pion.

Source officielle

https://en.wikipedia.org/wiki/Scalar_boson

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Personnes associées (32)

Matthias Finger

Konstantin Androsov

Lesya Shchutska

Roberto Castello

Roberto Castello is a senior scientist and group leader at the EPFL Laboratory of Solar Energy and Building Physics. Physicist by training, he has extensive experience in collecting, classifying and interpreting large datasets using advanced data mining techniques and statistical methods. He received his MSc (2007) in Particle Physics and PhD (2010) in Physics and Astrophysics from the University of Torino. He worked as a postdoctoral researcher at the Belgian National Research Fund (2011-2014) and at the CERN Experimental Physics Department (2015-2017) as a research fellow and data scientist. He is primary author of more than 20 peer-reviewed publications and he presented at major international conferences in the high energy physics domain. In 2018 he joined the Solar Energy and Building Physics Laboratory (LESO-PB) to work on data mining and Machine Learning techniques for the built environment and renewable energy. His main research interests are: spatio-temporal modeling of renewable energy potential, energy consumption forecasting techniques, anomaly detection, and computer vision techniques for automated classification in the built environment. He leads the group of Urban Data Mining, Intelligence and Simulation at LESO-PB and he is a member of the NRP75 Big Data project (HyEnergy) of the Swiss National Science Foundation. He is a member of the Swiss Competence Centre for Energy Research (SCCER) and deputy leader of the working group on Leveraging Ubiquitous Energy Data. He has served as a scientific committee member, workshop organizer and speaker at international conferences (ICAE 2020, Applied Machine Learning Days 2019 and 2020, CISBAT 2019 and 2021 and SDS2020). Since 2017 he is member of the Geneva 2030 Ecosystem network, promoting the United Nations agenda towards the realization of the Sustainable Development Goals (SDGs).

Alessandro Degano

Concepts associés (3)

thumb|De gauche à droite : Kibble, Guralnik, Hagen, Englert et Brout, en 2010. Le boson de Higgs ou boson BEH, est une particule élémentaire dont l'existence, postulée indépendamment en juin 1964 par François Englert et Robert Brout, par Peter Higgs, en août, et par Gerald Guralnik, Carl Richard Hagen et Thomas Kibble, permet d'expliquer la brisure de l'interaction unifiée électrofaible (EWSB, pour l'anglais ) en deux interactions par l'intermédiaire du mécanisme de Brout-Englert-Higgs-Hagen-Guralnik-Kibble et d'expliquer ainsi pourquoi certaines particules ont une masse et d'autres n'en ont pas.

En mécanique quantique, un boson est une particule subatomique de spin entier qui obéit à la statistique de Bose-Einstein. Le théorème spin-statistique différencie les bosons des fermions, qui ont un spin demi-entier. La famille des bosons inclut des particules élémentaires : les photons, les gluons, les bosons Z et W (ce sont les quatre bosons de jauge du modèle standard), le boson de Higgs (découvert en 2012), et le graviton encore théorique ; ainsi que des particules composites (les mésons et les noyaux qui ont un nombre de masse pair comme le deutérium, l'hélium 4 ou le plomb 208) ; et quelques quasi-particules (paires de Cooper, plasmons et phonons).

Le 'spin' () est, en physique quantique, une des propriétés internes des particules, au même titre que la masse ou la charge électrique. Comme d'autres observables quantiques, sa mesure donne des valeurs discrètes et est soumise au principe d'incertitude. C'est la seule observable quantique qui ne présente pas d'équivalent classique, contrairement, par exemple, à la position, l'impulsion ou l'énergie d'une particule. Il est toutefois souvent assimilé au moment cinétique (cf de cet article, ou Précession de Thomas).