Êtes-vous un étudiant de l'EPFL à la recherche d'un projet de semestre?
Travaillez avec nous sur des projets en science des données et en visualisation, et déployez votre projet sous forme d'application sur GraphSearch.
Concept
Force carrier
Résumé
In quantum field theory, a force carrier (also known as a messenger particle, intermediate particle, or exchange particle) is a type of particle that gives rise to forces between other particles. These particles serve as the quanta of a particular kind of physical field.
Wave–particle duality
Quantum field theories describe nature in terms of fields. Each field has a complementary description as the set of particles of a particular type. A force between two particles can be described either as the action of a force field generated by one particle on the other, or in terms of the exchange of virtual force carrier particles between them.
The energy of a wave in a field (for example, electromagnetic waves in the electromagnetic field) is quantized, and the quantum excitations of the field can be interpreted as particles. The Standard Model contains the following particles, each of which is an excitation of a particular field:
Gluons, excitations of the strong gauge field.
Photons, W bosons, and Z bosons, excitations of the electroweak gauge fields.
Higgs bosons, excitations of one component of the Higgs field, which gives mass to fundamental particles.
In addition, composite particles such as mesons, as well as quasiparticles, can be described as excitations of an effective field.
Gravity is not a part of the Standard Model, but it is thought that there may be particles called gravitons which are the excitations of gravitational waves. The status of this particle is still tentative, because the theory is incomplete and because the interactions of single gravitons may be too weak to be detected.
Static forces and virtual-particle exchange
When one particle scatters off another, altering its trajectory, there are two ways to think about the process. In the field picture, we imagine that the field generated by one particle caused a force on the other. Alternatively, we can imagine one particle emitting a virtual particle which is absorbed by the other. The virtual particle transfers momentum from one particle to the other.
Source officielle
À propos de ce résultat
Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.
Concepts associés (55)
Force carrier
In quantum field theory, a force carrier (also known as a messenger particle, intermediate particle, or exchange particle) is a type of particle that gives rise to forces between other particles. These particles serve as the quanta of a particular kind of physical field. Wave–particle duality Quantum field theories describe nature in terms of fields. Each field has a complementary description as the set of particles of a particular type.
Boson de jauge
En physique des particules, un boson de jauge est une particule élémentaire de la classe des bosons qui agit comme porteur d'une interaction élémentaire. Plus spécifiquement, les particules élémentaires dont les interactions sont décrites par une théorie de jauge exercent l'une sur l'autre des forces par échange de bosons de jauge, généralement sous forme de particules virtuelles. Le modèle standard décrit trois sortes de bosons de jauge : les photons, les bosons W et Z et les gluons.
Théorie de jauge
En physique théorique, une théorie de jauge est une théorie des champs basée sur un groupe de symétrie locale, appelé groupe de jauge, définissant une « invariance de jauge ». Le prototype le plus simple de théorie de jauge est l'électrodynamique classique de Maxwell. L'expression « invariance de jauge » a été introduite en 1918 par le mathématicien et physicien Hermann Weyl. La première théorie des champs à avoir une symétrie de jauge était la formulation de l'électrodynamisme de Maxwell en 1864 dans .
Cours associés (5)
PHYS-415: Particle physics I
Presentation of particle properties, their symmetries and interactions.
Introduction to quantum electrodynamics and to the Feynman rules.
ME-469: Nano-scale heat transfer
In this course we study heat transfer (and energy conversion) from a microscopic perspective. First we focus on understanding why classical laws (i.e. Fourier Law) are what they are and what are their
PHYS-432: Quantum field theory II
The goal of the course is to introduce relativistic quantum field theory as the conceptual and mathematical framework describing fundamental interactions such as Quantum Electrodynamics.