Editing Standard Model (section)

=== Gauge bosons ===
[[File:Standard Model – All Feynman diagram vertices.svg|upright=1.5|thumb|right|class=skin-invert-image|Interactions in the Standard Model. All Feynman diagrams in the model are built from combinations of these vertices. ''q'' is any quark, ''g'' is a gluon, 

''X'' is any charged particle, γ is a photon, ''f'' is any fermion, ''m'' is any particle with mass (with the possible exception of the neutrinos), ''m''<sub>B</sub> is any boson with mass. 

In diagrams with multiple particle labels separated by '/', one particle label is chosen. In diagrams with particle labels separated by '<nowiki>|</nowiki>', the labels must be chosen in the same order. For example, in the four boson electroweak case the valid diagrams are WWWW, WWZZ, WWγγ, WWZγ. The conjugate of each listed vertex (reversing the direction of arrows) is also allowed.<ref>{{cite thesis |type=PhD |last=Lindon |first=Jack |date=2020 |title=Particle Collider Probes of Dark Energy, Dark Matter and Generic Beyond Standard Model Signatures in Events With an Energetic Jet and Large Missing Transverse Momentum Using the ATLAS Detector at the LHC |publisher=CERN |url=https://cds.cern.ch/record/2746537/ }}</ref>]]

The Standard Model includes 4 kinds of [[gauge boson]]s of [[Spin (physics)|spin]] 1,<ref name=":0" /> with bosons being quantum particles containing an integer spin. The gauge bosons are defined as [[force carrier]]s, as they are responsible for mediating the [[fundamental interaction]]s. The Standard Model explains the four fundamental forces as arising from the interactions, with fermions [[Static forces and virtual-particle exchange|exchanging]] [[Virtual particle|virtual]] force carrier particles, thus mediating the forces. At a macroscopic scale, this manifests as a [[force]].<ref>{{cite journal |last1=Jaeger |first1=Gregg |year=2021 |title=Exchange Forces in Particle Physics |journal=Foundations of Physics |volume=51 |issue=1 |page=13 |bibcode=2021FoPh...51...13J |doi=10.1007/s10701-021-00425-0 |s2cid=231811425}}</ref> As a result, they do not follow the Pauli exclusion principle that constrains fermions; bosons do not have a theoretical limit on their [[volume number density|spatial density]]. The types of gauge bosons are described below.
* [[Electromagnetism]]: [[Photon]]s mediate the electromagnetic force, responsible for interactions between electrically charged particles. The photon is massless and is described by the theory of [[quantum electrodynamics]] (QED).
* [[Strong interaction|Strong Interactions]]: [[Gluon]]s mediate the strong interactions, which binds quarks to each other by influencing the [[color charge]], with the interactions being described in the theory of [[quantum chromodynamics]] (QCD). They have no mass, and there are eight distinct gluons, with each being denoted through a color-anticolor charge combination (e.g. red–antigreen).{{NoteTag|Although nine color–anticolor combinations mathematically exist, gluons form color octet particles. As one color-symmetric combination is linear and forms a color singlet particles, there are eight possible gluons.<ref>{{Cite book |last1=Cahn |first1=Robert N. |title=The Experimental Foundations of Particle Physics |last2=Goldbaher |first2=Gerson |publisher=[[Cambridge University Press]] |year=2010 |isbn=978-0521521475 |edition=2nd |publication-date=August 31, 2009 |pages=306 |chapter=Quarks, gluons, and jets |chapter-url=http://hitoshi.berkeley.edu/129A/Cahn-Goldhaber/chapter10.pdf |chapter-format=[[PDF]] |archive-url=https://web.archive.org/web/20120714015451/http://hitoshi.berkeley.edu/129A/Cahn-Goldhaber/chapter10.pdf |archive-date=July 14, 2012 |url-status=live}}</ref>}} As gluons have an effective color charge, they can also interact amongst themselves.
* [[Weak interaction|Weak Interactions]]: The [[W and Z bosons|{{SubatomicParticle|W boson+}}, {{SubatomicParticle|W boson-}}, and {{SubatomicParticle|Z boson}}]] gauge bosons mediate the weak interactions between all fermions, being responsible for [[Radioactive decay|radioactivity]]. They contain mass, with the {{SubatomicParticle|Z boson}} having more mass than the {{SubatomicParticle|W boson+-}}. The weak interactions involving the {{SubatomicParticle|W boson+-}} act only on [[Chirality (physics)|''left-handed'' particles and ''right-handed'' antiparticles]] respectively. The {{SubatomicParticle|W boson+-}} carries an electric charge of +1 and −1 and couples to the electromagnetic interaction. The electrically neutral {{SubatomicParticle|Z boson}} boson interacts with both left-handed particles and right-handed antiparticles. These three gauge bosons along with the photons are grouped together, as collectively mediating the [[electroweak]] interaction.
* [[Gravity]]: It is currently unexplained in the Standard Model, as the hypothetical mediating particle [[graviton]] has been proposed, but not observed.<ref>{{Cite web |last=Hooper |first=Dan |date=2022-05-19 |title=What is the Standard Model of particle physics, and why are scientists looking beyond it? |url=https://www.astronomy.com/science/what-is-the-standard-model-of-particle-physics-and-why-are-scientists-looking-beyond-it/ |access-date=2024-01-20 |website=[[Astronomy Magazine]] |language=en-US}}</ref> This is due to the incompatibility of quantum mechanics and [[General relativity|Einstein's theory of general relativity]], regarded as being the best explanation for gravity. In general relativity, gravity is explained as being the geometric curving of spacetime.<ref>{{Cite news |last=Butterworth |first=Jon |date=2014-06-01 |title=Gravity versus the Standard Model |url=https://www.theguardian.com/science/life-and-physics/2014/jun/01/gravity-versus-the-standard-model |access-date=2024-01-20 |work=[[The Guardian]] |language=en-GB |issn=0261-3077}}</ref>
The [[Feynman diagram]] calculations, which are a graphical representation of the [[perturbation theory (quantum mechanics)|perturbation theory]] approximation, invoke "force mediating particles", and when applied to analyze [[particle accelerator|high-energy scattering experiments]] are in reasonable agreement with the data. However, perturbation theory (and with it the concept of a "force-mediating particle") fails in other situations. These include low-energy quantum chromodynamics, [[bound state]]s, and [[soliton]]s. The interactions between all the particles described by the Standard Model are summarized by the diagrams on the right of this section.