Discrete spectral triples converging to dirac operators

نویسنده

  • Alejandro Rivero
چکیده

We exhibit a series of discrete spectral triples converging to the canonical spectral triple of a finite dimensional manifold. Thus we bypass the non-go theorem of Gökeler and Schücker. Sort of counterexample. In [2] Connes gave the most general example of non commutative manifolds defined from finite spectral triples, and such discrete manifolds were classified independently by Krajewsky [5, 6] and Paschke and Sitarz [7] the same year. But almost the same time, Gökeler and Schücker [3] proved that the naive discretizations of Dirac Operators were not able to fulfil the axioms of non-commutative manifolds. This caused a fading in the attempts to illuminate NCG from the point of view of lattice theories. Later attempts to show NCG operations in lattices have preferred to avoid the full axiomatic required by K-theory and Reality . But the subsequent works on lattices, from the successful show of Lüscher with the index theorem, to the insistent studies of Jian Dai or M. Requardt, to name some ones, should invite us to try to develop the full geometric set-up. In [3], the non-go principles also ruled out some non-naive formulations. At that time, inspired on some previous speculations, I risked to suggest privately the use of a doubling of the representation of the algebra, thus a function A(x), x in one dimension, could be discretized to an operator A(i) with representation: A|v >= 

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Spectral triples of weighted groups

We study spectral triples on (weighted) groups and consider functors between the categories of weighted groups and spectral triples. We study the properties of weights and the corresponding functor for spectral triples coming from discrete weighted groups.

متن کامل

Quasi-Dirac Operators and Quasi-Fermions

We investigate examples of quasi-spectral triples over two-dimensional commutative sphere, which are obtained by modifying the order-one condition. We find equivariant quasi-Dirac operators and prove that they are in a topologically distinct sector than the standard Dirac operator. MSC 2000: 58B34, 46L87, 34L40

متن کامل

Quasi-Dirac Operators on the Sphere

We investigate examples of quasi-spectral triples over two-dimensional commutative sphere, which are obtained by modifying the order-one condition. We find quasi-Dirac operators and calculate the index paring with a representant of K-theory class to prove that the quasispectral triples are mutually inequivalent. MSC 2000: 58B34, 46L87, 34L40

متن کامل

Equivariant spectral triples for SUq(l + 1) and the odd dimensional quantum spheres

We formulate the notion of equivariance of an operator with respect to a covariant representation of a C∗-dynamical system. We then use a combinatorial technique used by the authors earlier in characterizing spectral triples for SUq(2) to investigate equivariant spectral triples for two classes of spaces: the quantum groups SUq(l+1) for l > 1, and the odd dimensional quantum spheres S q of Vaks...

متن کامل

Twisted Dirac Operators over Quantum Spheres

We construct new families of spectral triples over quantum spheres, with a particular attention focused on the standard Podleś quantum sphere and twisted Dirac operators.

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2002