Krajewski diagrams and spin lifts

We briefly sketch the noncommutative geometry approach to the Standard Model, with attention to what can be inferred about particle masses.

The standard model fermion spectrum, including a right handed neutrino, can be obtained as a zero-mode of the Dirac operator on a space which is the product of complex projective spaces of complex dimension two and three. The construction requires the introduction of topologically non-trivial background gauge fields. By borrowing from ideas in Connes' non-commutative geometry and making the complex spaces `fuzzy' a matrix approximation to the fuzzy space allows for three gene...

These notes present the details of the computation of massless and massive spinor triangle loops for consistent anomalies in gauge theories.

A solution to the generation puzzle based on a nonabelian generalization of electric-magnetic duality is briefly reviewed. It predicts 3 and only 3 generations of fermions and explains the hierarchical mass spectrum as well as the main features in both the quark and lepton mixing matrices. A calculation to leading perturbative order already gives reasonable values to about half of the Standard Model parameters.

In this publication we present an extension of the Standard Model within the framework of Connes' noncommutative geometry [1]. The model presented here is based on a minimal spectral triple [7] which contains the Standard Model particles, new vectorlike fermions and a new U(1) gauge subgroup. Additionally a new complex scalar field appears that couples to the right-handed neutrino, the new fermions and the standard Higgs particle. The bosonic part of the action is given by th...

The subject of this PhD thesis is noncommutative geometry - more specifically spectral triples - and how it can be generalized to semi-Riemannian manifolds generally, and Lorentzian manifolds in particular. The first half of this thesis will thus be dedicated to the transition from Riemannian to semi-Riemannian manifolds. This entails a study of Clifford algebras for indefinite vector spaces and Spin structures on semi-Riemannian manifolds. An important consequence of this is...

We introduce a new formulation of the real-spectral-triple formalism in non-commutative geometry (NCG): we explain its mathematical advantages and its success in capturing the structure of the standard model of particle physics. The idea, in brief, is to represent $A$ (the algebra of differential forms on some possibly-noncommutative space) on $H$ (the Hilbert space of spinors on that space), and to reinterpret this representation as a simple super-algebra $B=A\oplus H$ with ...

It is pointed out that there are infinite classes of cases based on gauge groups of the form SU(p)xSU(q)xU(1) in which gauge anomalies cancel non-trivially for small sets of fermion multiplets that include symmetric tensor representations. These cancellations are non-trivial in the sense that no group-theoretic explanation in terms of embedding in a larger simple group is apparent. The cases presented here could be useful for model building and lead to models with extra lepto...

This is a review of recent results regarding the application of Connes' noncommutative geometry to the Standard Model, and beyond. By twisting (in the sense of Connes-Moscovici) the spectral triple of the Standard Model, one does not only get an extra scalar field which stabilises the electroweak vacuum, but also an unexpected 1-form field. By computing the fermionic action, we show how this field induces a transition from the Euclidean to the Lorentzian signature. Hints on a...

The principles of noncommutative geometry impose severe restrictions on the structure of (almost) commutative field theories. The Standard Model fits surprisingly well into the noncommutative framework. Here we overview some universal predictions of the spectral action principle for the behavior of bosonic theories at very high energies.