Content deleted Content added
minor correction |
some cleanup |
||
(43 intermediate revisions by 18 users not shown) | |||
Line 1:
In theoretical [[particle physics]], the '''non-commutative Standard Model''' (best known as '''Spectral Standard Model'''<ref name="10.1007/JHEP09(2012)104">
{{cite journal | title = Resilience of the Spectral Standard Model
| last1 = Chamseddine | first1 = A.H.
Line 6 ⟶ 5:
| author1-link = Ali Chamseddine
| author2-link = Alain Connes
| journal = [[
| year = 2012
| volume = 2012 | issue = 9 | page = 104
| doi = 10.1007/JHEP09(2012)104
| arxiv = 1208.1030 | bibcode = 2012JHEP...09..104C | s2cid = 119254948
}}</ref><ref name="10.1007/JHEP11(2013)132">
{{cite journal | title = Beyond the Spectral Standard Model: Emergence of Pati-Salam Unification
| last1 = Chamseddine | first1 = A.H.
Line 19 ⟶ 17:
| author1-link = Ali Chamseddine
| author2-link = Alain Connes
| journal = [[
| year = 2013
| volume = 2013 | issue = 11 | page = 132
| doi = 10.1007/JHEP11(2013)132
| arxiv = 1304.8050 | bibcode = 2013JHEP...11..132C | s2cid = 18044831 }}
</ref>), is a model based on [[noncommutative geometry]] that unifies a modified form of [[general relativity]] with the [[Standard Model]] (extended with right-handed neutrinos).
The model postulates that space-time is the product of a 4-dimensional compact spin manifold <math>\mathcal{M}</math> by a finite space <math>\mathcal{F}</math>. The full Lagrangian (in Euclidean signature) of the [[Standard
The parameters of the model live at unification scale and physical predictions are obtained by running the parameters down through [[
It is worth stressing that it is more than a simple reformation of the [[Standard Model]]. For example, the scalar sector and the fermions representations are more constrained than in [[
== Motivation ==
Following ideas from [[
The group of invariance of such a space should combine the group of invariance of [[general relativity]] <math>\text{Diff}(\mathcal{M})</math> with <math>\mathcal{G} = \text{Map}(\mathcal{M}, G)</math>, the group of maps from <math>\mathcal{M}</math> to the
<math>\text{Diff}(\mathcal{M})</math> acts on <math>\mathcal{G}</math> by permutations and the full group of symmetries of <math>\mathcal{X}</math> is the semi-direct product:
<math>\text{Diff}(\mathcal{X}) = \mathcal{G} \rtimes \text{Diff}(\mathcal{M})</math>
Note that the group of invariance of <math>\mathcal{X}</math> is not a simple group as it always contains the normal subgroup <math>\mathcal{G}</math>. It was proved by Mather<ref name="10.1090/S0002-9904-1974-13456-7">
{{cite journal
| last = Mather | first = John N.
| journal = Bulletin of the American Mathematical Society
Line 49 ⟶ 46:
| issue = 2
| year = 1974
| pages =
| doi = 10.1090/S0002-9904-1974-13456-7 | doi-access = free
}}</ref>
and Thurston<ref name="10.1090/S0002-9904-1974-13475-0">
{{cite journal
| title = Foliations and groups of diffeomorphisms
| last = Thurston | first = William
| journal = Bulletin of the American Mathematical Society
| volume = 80
| year = 1974
| issue = 2 | pages =
| url = http://projecteuclid.org/euclid.bams/1183535407
| doi = 10.1090/S0002-9904-1974-13475-0 | doi-access = free
}}
</ref>
that for ordinary (commutative) manifolds, the connected component of the identity in <math>\text{Diff}(\mathcal{M})</math> is always a simple group, therefore no ordinary manifold can have this semi-direct product structure.
It is nevertheless possible to find such a space by enlarging the notion of space.
In
Picking different algebras then give rise to different symmetries. The Spectral Standard Model takes as input the algebra <math>A = C^{\infty}(M) \otimes A_F </math> where <math>C^{\infty}(M)</math> is the algebra of differentiable functions encoding the 4-dimensional manifold and <math>A_F = \mathbb{C} \oplus \mathbb{H} \oplus M_3(\mathbb{C})</math> is a finite dimensional algebra encoding the symmetries of the
== History ==
First ideas to use
{{cite book
| last = Connes | first = Alain | author-link = Alain Connes
| year= 1990
| chapter = Essay on physics and noncommutative geometry
|
|
| series=Inst. Math. Appl. Conf. Ser., New Ser. |volume=24
| publisher=Oxford University Press
| ___location=New York
}}</ref><ref name="dv_1988_dcdnc">
{{cite journal | title = Dérivations et calcul différentiel non commutatif
| last = Dubois-Violette | first = Michel
| journal = Comptes Rendus de l'Académie des Sciences, Série I
| issue = 307
| pages =
| year = 1988
}}</ref><ref name="DVKM_1989_CBNG">
{{cite journal | title = Classical bosons in a non-commutative geometry
| last1 = Dubois-Violette | first1 = Michel
Line 100 ⟶ 96:
| number = 11
| year = 1989
| page = 1709 | doi = 10.1088/0264-9381/6/11/023 | bibcode = 1989CQGra...6.1709D | s2cid = 250880966
}}</ref><ref name="10.1016/0370-2693(89)90083-X">
{{cite journal | title = Gauge bosons in a noncommutative geometry
| last1 = Dubois-Violette | first1 = Michel
Line 111 ⟶ 106:
| issue = 4
| year = 1989
| pages =
| doi = 10.1016/0370-2693(89)90083-X
| bibcode = 1989PhLB..217..485D
}}</ref><ref name="10.1063/1.528917">
{{cite journal | title = Noncommutative differential geometry and new models of gauge theory
| last1 = Dubois-Violette | first1 = Michel
Line 124 ⟶ 118:
| issue = 31
| year = 1989
| pages =
| doi = 10.1063/1.528917
}}</ref> and were formalized a couple of years later by [[Alain Connes]] and [[John Lott (mathematician)|John Lott]] in what is known as the Connes-Lott model
.<ref name="10.1016/0920-5632(91)90120-4">
{{cite journal | title = Particle models and noncommutative geometry
| last1 = Connes | first1 = Alain
| last2 = Lott | first2 = John
| author1-link = Alain Connes
| author2-link = John Lott (mathematician)
| journal = Nuclear Physics B - Proceedings Supplements
| year = 1991
| volume = 18 | issue = 2 | pages = 29–47 | doi = 10.1016/0920-5632(91)90120-4
| bibcode = 1991NuPhS..18...29C | hdl = 2027.42/29524 | hdl-access = free
}}</ref> The Connes-Lott model did not incorporate the gravitational field.
In 1997, [[Ali Chamseddine]] and
{{cite journal | title = The Spectral Action Principle
| last1 = Chamseddine | first1 = Ali H.
Line 149 ⟶ 139:
| author1-link = Ali Chamseddine
| author2-link = Alain Connes
| journal = Communications in Mathematical Physics
| pages = 731–750
| year = 1997
| volume = 186 | issue = 3
| doi = 10.1007/s002200050126 | arxiv = hep-th/9606001 | bibcode = 1997CMaPh.186..731C | s2cid = 12292414
}}</ref> that made possible to incorporate the gravitational field into the model. Nevertheless, it was quickly noted that the model suffered from the notorious fermion-doubling problem (quadrupling of the fermions)
<ref name="10.1103/PhysRevD.55.6357">
{{cite journal
| title = Fermion Hilbert Space and Fermion Doubling in the Noncommutative Geometry Approach to Gauge Theories | last1 = Lizzi | first1 = Fedele
| last2 = Mangano | first2 = Gianpiero
Line 166 ⟶ 156:
| issue = 10
| year = 1997
| pages = 6357–6366 | doi = 10.1103/PhysRevD.55.6357
| arxiv = hep-th/9610035 | bibcode = 1997PhRvD..55.6357L | s2cid = 14692679
}}</ref>
<ref name="10.1016/S0370-2693(97)01310-5">
{{cite journal
| title = The standard model in noncommutative geometry and fermion doubling | last1 = Gracia-Bondía | first1 = Jose M.
| last2 = Iochum | first2 = Bruno
| last3 = Schücker | first3 = Thomas
| journal = Physical Review B
|
| pages = 123–128
| year = 1998
| issue = 1–2 | doi = 10.1016/S0370-2693(97)01310-5
| arxiv = hep-th/9709145
| bibcode = 1998PhLB..416..123G | s2cid = 15557600 }}
</ref> and required neutrinos to be massless. One year later, experiments in [[Super-Kamiokande]] and [[Sudbury Neutrino Observatory]] began to show that solar and atmospheric neutrinos change flavors and therefore are massive, ruling out the Spectral Standard Model.
Only in 2006 a solution to the latter problem was proposed, independently by [[John W. Barrett (physicist)|John W. Barrett]]<ref name="10.1063/1.2408400">
{{cite journal
| last = Barrett | first = John W.
| author-link=John W. Barrett (physicist)
| journal = Journal of Mathematical Physics
|
| year = 2007
| issue = 1 | page = 012303
| doi = 10.1063/1.2408400
| arxiv = hep-th/0608221 | bibcode = 2007JMP....48a2303B | s2cid = 11511575
}}</ref> and Alain Connes,<ref name="10.1088/1126-6708/2006/11/081">
{{cite journal
| title = Noncommutative Geometry and the standard model with neutrino mixing
| last = Connes | first = Alain
| author-link=Alain Connes
Line 201 ⟶ 193:
| volume = 2006
| year = 2006
| issue = 11 | page = 081
| doi = 10.1088/1126-6708/2006/11/081
| arxiv = hep-th/0608226 | bibcode = 2006JHEP...11..081C | s2cid = 14419757
}}</ref> almost at the same time. They show that massive neutrinos can be incorporated into the model by disentangling the KO-dimension (which is defined modulo 8) from the metric dimension (which is zero) for the finite space. By setting the KO-dimension to be 6, not only massive neutrinos were possible, but the see-saw mechanism was imposed by the formalism and the fermion doubling problem was also addressed.
The new version of the model was studied in,<ref name="10.4310/ATMP.2007.v11.n6.a3">
{{cite journal | title = Gravity and the standard model with neutrino mixing
| last1 = Chamseddine | first1 = Ali H.
Line 218 ⟶ 207:
| author3-link = Matilde Marcolli
| journal = Advances in Theoretical and Mathematical Physics
| volume = 11 | number = 6
|
|
| doi = 10.4310/ATMP.2007.v11.n6.a3 | arxiv = hep-th/0610241 | s2cid = 9042911
}}</ref> and under an additional assumption, known as the "big desert" hypothesis, computations were carried out to predict the [[Higgs boson]] mass around 170 [[GeV]] and postdict the [[top quark]] mass.
In August 2008, [[Tevatron]] experiments<ref name="arxiv:0808.0534">
{{cite book
| author = CDF and D0 Collaborations and Tevatron New Phenomena Higgs Working Group
|
| year = 2008
| arxiv = 0808.0534
}}</ref> excluded a Higgs mass of 158 to 175 GeV/''c''<sup>2</sup> at the 95% confidence level. Alain Connes acknowledged on a blog about non-commutative geometry that the prediction about the Higgs mass was invalidated.<ref>
{{cite web
| title = Irony
|
| access-date=4 August 2008
| url = https://noncommutativegeometry.blogspot.com/2008/08/irony.html
}}</ref> In July 2012, CERN announced the discovery of the [[Higgs boson]] with a mass around 125
A proposal to address the problem of the Higgs mass was published by [[Ali Chamseddine]] and
<ref name="10.1007/JHEP09(2012)104"/> by taking into account a real scalar field that was already present in the model but was neglected in previous analysis.
Another solution to the Higgs mass problem was put forward by Christopher Estrada and [[Matilde Marcolli]] by studying renormalization group flow in presence of gravitational correction terms.<ref name="10.1142/S0219887813500369">
{{cite journal
| last1 = Estrada | first1 =Christopher
| last2 = Marcolli | first2 = Matilde
Line 257 ⟶ 240:
| number = 7
| year = 2013
| pages = 1350036–68
| doi = 10.1142/S0219887813500369
| arxiv = 1208.5023 | bibcode = 2013IJGMM..1050036E | s2cid = 215930 }}
</ref>
== See also ==
* [[Noncommutative geometry]]
* [[Noncommutative
* [[Noncommutative quantum field theory]]
* [[Timeline of atomic and subatomic physics]]
== Notes ==
{{reflist}}
== References ==
*
* {{cite journal |last1=Connes |first1=Alain |author-mask=1 |year=1995 |title=Noncommutative geometry and reality |journal=Journal of Mathematical Physics |volume=36 |issue=11 |pages=6194–6231|doi=10.1063/1.531241 |bibcode=1995JMP....36.6194C |url=https://cds.cern.ch/record/285273 }}
*
* {{cite web |last1=Connes |first1=Alain |author-
*
* {{cite journal |arxiv=hep-th/9606001 |doi=10.1007/s002200050126 |title=The Spectral Action Principle |year=1997 |last1=Chamseddine |first1=Ali H. |last2=Connes |first2=Alain |journal=Communications in Mathematical Physics |volume=186 |issue=3 |pages=731–750 |bibcode=1997CMaPh.186..731C |s2cid=12292414}}
* {{cite journal |arxiv=hep-th/0610241 |doi=10.4310/ATMP.2007.v11.n6.a3 |title=Gravity and the standard model with neutrino mixing |year=2007 |last1=Chamseddine |first1=Ali H. |last2=Connes |first2=Alain |last3=Marcolli |first3=Matilde |journal=Advances in Theoretical and Mathematical Physics |volume=11 |issue=6 |pages=991–1089 |s2cid=9042911}}
* {{cite journal |arxiv=0705.0489 |last1=Jureit
* {{cite book |doi=10.1007/978-3-540-31532-2_6 | arxiv=hep-th/0111236 | last1=Schucker | first1=Thomas | title=Topology and Geometry in Physics | chapter=Forces from Connes' Geometry | series=Lecture Notes in Physics | year=2005 | volume=659 | pages=285–350 | bibcode=2005LNP...659..285S| isbn=978-3-540-23125-7 | s2cid=16354019 }}
== External links ==
* [http://www.alainconnes.org/ Alain Connes's official website] with [http://www.alainconnes.org/en/downloads.php downloadable papers.]
* [
{{DEFAULTSORT:Noncommutative Standard Model}}
[[Category:
[[Category:Noncommutative geometry]]
|