Top PDF Projective Dirac Operators, Twisted K-Theory, and Local Index Formula

Projective Dirac Operators, Twisted K-Theory, and Local Index Formula

Projective Dirac Operators, Twisted K-Theory, and Local Index Formula

many nice properties such as “the five conditions” in Connes [8], and conversely, it is proved that [8] any commutative spectral triple (A, H, D, γ) satisfying those five conditions is equivalent to a spectral triple consisting of the algebra of smooth functions on a Riemannian manifold M , the module of sections of a Clifford bundle over M and a Dirac type operator on it. Furthermore, if (A, H, D, γ) satisfies an additional important property – the Poincar´ e duality in K-theory – which means (A, H, D, γ) represents the fundamental class (i.e., a K-orientation) in K 0 (A), then it is
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Analysis on Vector Bundles over Noncommutative Tori

Analysis on Vector Bundles over Noncommutative Tori

by (2.10), where the Dirac operator is associated with a conformally flat metric and the twisting is carried out by an idempotent playing the role of a general vector bundle. In forthcoming work, we will present a simplification of the local formula and will elaborate on the relation between properties of the functions of the modular automorphism in the simplified form and stability of the index under perturbations that leave the Dirac operator in the same connected component of Fredholm operators. We end this article by considering the case of the canonical flat metric on T 2 θ , which corresponds to the trivial conformal factor k = 1 whose corresponding modular automorphism ∆ is the identity. Therefore, our formula for the index, in this case, reduces to a much simpler form, as one can replace the functions of the modular automorphism with the values of the functions at 1. This yields, for k = 1 [68]:
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ABSTRACT BOTT-CHERN CHARACTERISTIC FORMS AND INDEX THEOREMS FOR COHERENT SHEAVES ON COMPLEX MANIFOLDS

ABSTRACT BOTT-CHERN CHARACTERISTIC FORMS AND INDEX THEOREMS FOR COHERENT SHEAVES ON COMPLEX MANIFOLDS

operator: E 00 + E 00,∗ . We call it the generalized Dolbeault-Dirac operator and relate it to the theory of Clifford module and generalized Dirac operators in chapter 5. Using the heat kernel method for Clifford superconnection presented in [BGV91], we obtain the following index formula for the Euler characteristic of cohesive modules that extends classical the Hirzebruch-Riemann-Roch formula.

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Dirac operators in tensor categories and the motive of quaternionic modular forms

Dirac operators in tensor categories and the motive of quaternionic modular forms

The aim of this paper is to define a motive whose realizations afford modular forms (of arbitrary weight) on an indefinite division quaternion algebra. The idea of the construction, once again, is due to Jordan and Livn´e. However some remarks are in order. First, it is worth noting that although the realizations of the motive constructed in this paper are abstractly isomorphic to the D = disc(B)-new part of (two copies of) the realizations of the motive constructed in [Sc] via the Jacquet–Langlands correspondence, a “motivic Jacquet–Langlands correspondence” has not yet described that lifts this correspondence to the motivic setting. Therefore what we propose is the first construction –as a Chow motive– of D-new modular forms. Second, following their construction in this indefinite setting and working at the level of realizations gives the various incarnations of two copies of odd weight modular forms, rather than just one copy. It is not possible to canonically split them in a single copy: this is possible only including a splitting field for the quaternion algebra in the coefficients, but the resulting splitting depends on the choice of an identification of the base changed algebra with the split quaternion algebra. Indeed, we will construct a motive whose realizations afford two copies of odd weight modular forms. Finally, the idea of Jordan and Livn´e is to construct square roots of the Laplace operators after appropriately tensoring the source and the targets of ∆ n ; however the
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Vector Fields on Spheres

Vector Fields on Spheres

In this chapter, we will compute the K -theory of stunted projective space and their corresponding Adams’ operations. This will form a major component of the proof that R P n+ρn / R P n−1 is not coreducible. However, we will include every stunted projective space, for completeness, even if it is not used in the vector fields problem. We will generally use the notation R P n / R P m instead of R P n m+1 to emphasise that we only

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Multivariate Twisted  Adic  Integral on  Associated with Twisted  Bernoulli Polynomials and Numbers

Multivariate Twisted Adic Integral on Associated with Twisted Bernoulli Polynomials and Numbers

the polynomials and numbers are called the twisted q-Bernoulli polynomials and numbers, respectively. When k 1 and q 1, the polynomials and numbers are called the twisted Bernoulli polynomials and numbers, respectively. When k 1, q 1, and ζ 1, the polynomials and numbers are called the ordinary Bernoulli polynomials and numbers, respectively.

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Boundary value problems for modified Dirac operators in Clifford analysis

Boundary value problems for modified Dirac operators in Clifford analysis

The uniqueness and existence theorems for the solutions of boundary value problems for systems of partial differential equations are sufficiently well known. Such problems have remarkable applications in mathematical physics, the mechanics of deformable bodies, electromagnetism, relativistic quantum mechanics, and some of their natural generaliza- tions. Almost all such problems can be set in the context of Clifford analysis (see [, ]). Clifford analysis is centered around the concept of monogenic functions, i.e. null solu- tions of a first order vector valued rotation invariant differential operator called the Dirac operator which factorizes the Laplace operator (see [, ]). As to the mathematical study of boundary value problems in Clifford analysis, there are several different approaches known in the literature. Without claiming completeness, we mention some of them. First of all, we have the approach originating with Bernstein, whose approach is to translate boundary value problems to the corresponding singular integral equations, then use the properties of the Fredholm operator to discuss the solvability of singular integral equations (see []). Another important approach is based on complex analysis. In this case, first we use analytic function theory to solve these kinds of boundary value problems, then we use the results of boundary value problems to solve singular integral equations (see [, ]). The advantage of this method is that the explicit representation of solutions can be ob- tained, but in the higher dimensional space there still exist many obstacles to generalize this method. In this paper, we continue to use the method in [, ] to solve boundary value problems for the modified Dirac operators.
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Orientifolds and K-theory

Orientifolds and K-theory

In this section we compute the Ktheory relevant to the non-compact BZDP model and show that it agrees exactly with the D-brane spectrum found using BCFT tech- niques. We do this in two different ways; first we use a long exact sequence similar to the one in [8], then we show that the result can be easily obtained by using the connection between Clifford Algebras and Ktheory. The former method’s advan- tage is that it identifies which D-branes carry the same charges. This is particularily useful for torsion charged D-branes. The exact sequence method however, becomes quite cumbersome and it is sometimes difficult to disentangle the results.
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Inverse eigenvalue problem for a class of Dirac operators with discontinuous coefficient

Inverse eigenvalue problem for a class of Dirac operators with discontinuous coefficient

spectrum and norming constants was investigated in []. For the Dirac operator, the in- verse periodic and antiperiodic boundary value problems were given in [–]. Using the Weyl-Titschmarsh function, the direct and inverse problems for a Dirac type-system were developed in [, ]. Uniqueness of the inverse problem for the Dirac operator with a dis- continuous coefficient by the Weyl function was studied in [] and discontinuity condi- tions inside an interval were worked out in [, ]. The inverse problem for weighted Dirac equations was obtained in []. The reconstruction of the potential by the spectral function was given in []. For the Dirac operator with peculiarity, the inverse problem was found in []. Inverse nodal problems for the Dirac operator were examined in [, ]. In the case of potentials that belong entrywise to L p (, ), for some p ∈ [, ∞), the in-
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On singular projective deformations of two second class totally focal pseudocongruences of planes

On singular projective deformations of two second class totally focal pseudocongruences of planes

If K is a collineation realizing a projective deformation C of second order, ==3,4,..., and at the same time K realizes projective deformations of order i, 2, or then C is called weakly [r]

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Hermitean Cauchy Integral Decomposition of Continuous Functions on Hypersurfaces

Hermitean Cauchy Integral Decomposition of Continuous Functions on Hypersurfaces

of this system breaks down to the action of the special unitary group. The study of complex Dirac operators was initiated in 5–8; a systematic development of the associated function theory, including the invariance properties with respect to the underlying Lie groups and Lie algebras, is still in full progress see, e.g., 9–13.

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Hermitean Téodorescu Transform Decomposition of Continuous Matrix Functions on Fractal Hypersurfaces

Hermitean Téodorescu Transform Decomposition of Continuous Matrix Functions on Fractal Hypersurfaces

Again, a notion of two-sided H-monogenicity may be defined similarly. However, unless mentioned explicitly, we will only work with left H-monogenic matrix functions. This matrix approach has also been successfully applied in 17, 24 for the construction of a boundary values theory of h-monogenic functions.

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Unified Field Theory in a Nutshell—Elicit Dreams of a Final Theory Series

Unified Field Theory in a Nutshell—Elicit Dreams of a Final Theory Series

In § (2), we outline two fundamental reasons that call for a revision of Professor Einstein’s GTR. In § (3), we give an overview of the reading [5], and Professor Weyl’s [6] supposedly failed theory is brought back to life. In § (4), we demonstrate an important part of the unified theory to be developed, namely that the metric tensor is in-principle decomposable into a mathematical entity that has not ten free parameters, but four. In § (5), the spacetime upon with the present theory is build is laid down. In § (6), tensorial affinites are proposed in which even the desired spacetime is defined. Once the desired spacetime is defined, in § (7), the general field equations are written down and in § (8), it is shown that as a result of the tensorial nature of the affinities, it is possible to get rid of the non-linear terms of the resulting curvature tensor, thereby making the theory a linear theory. From this linear spacetime with tensorial affinities, in § (9), we write down the resulting field equation. Having laid down the theory, in § (10), we take stock of what has been achieved thus far. In § (11), we show how one can bring the gravitational force into the fold of the proposed unified theory. In § (12) we write down an appropriate geodesic equation that employs tensorial affinities. In § (13), we demonstrate that the proposed unified theory does contain Yang-Mills Theory and finally in § (14), (15) and (16), we give a general discussion, the conclusion drawn thereof and the recommendations for future works.
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Regularity theory on A harmonic system and A Dirac system

Regularity theory on A harmonic system and A Dirac system

In order to prove the main result, we also need a suitable Caccioppoli estimation (see Theorem .). Then by the technique of removable singularities, we can find that solutions to an A-harmonic system satisfying a Lipschitz condition or in the case of a bounded mean oscillation can be extended to Clifford valued solutions to the corresponding A-Dirac sys- tem.

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Semi Commutative Differential Operators Associated with the Dirac Opetator and Darboux Transformation

Semi Commutative Differential Operators Associated with the Dirac Opetator and Darboux Transformation

In the present paper, the semi-commutative differential oparators associated with the 1-dimensional Dirac operator are constructed. Using this results, the hierarchy of the mKdV (−) polynomials are expressed in terms of the KdV polyno- mials. These formulas give a new interpretation of the classical Darboux transformation and the Miura transformation. Moreover, the recursion operator associated with the hierarchy of the mKdV (−) polynomials is constructed by the al- gebraic method.

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The invariant subspace problem for absolutely p summing operators in Krein spaces

The invariant subspace problem for absolutely p summing operators in Krein spaces

The indefinite inner product · , · K on a Krein space K gives rise to a classification of elements of K. An element kK is called positive, negative, or neutral if k, k K > , k, k K < , or k, k K =  respectively. A linear manifold or a subspace L in K is called indefinite if it contains both positive and negative elements. We say that L is semi-definite if it is not indefinite. A semi-definite subspace L is called non-negative (positive, uniformly positive) if x, x ≥  (x, x > , x, x ≥ δ x, (δ > )) for all x in L. A non-positive (nega- tive, uniformly negative) subspace is defined in a similar way. We say that the subspace L is definite if x, x =  if and only if x = .
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Computing Szeged index of graphs on ‎triples

Computing Szeged index of graphs on ‎triples

Case 1 . i 0  . In this case we may take u  { 2,3} 1, and v   4, 5, 6  , the vertex w should be of distance 2 from v , hence should meet v and w  u   . If w meets v in one element we have 3/2(n − 6)(n − 7) choices for it and if it meets v in 2 elements again we have 3(n – 6) choices for it and the formula for Sz G  0  is obtained as above.

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Geometric algebras in physics: Eigenspinors and Dirac theory

Geometric algebras in physics: Eigenspinors and Dirac theory

The complex algebra of physical space, CAPS, is the complex extension of. APS. It is also the hyperbolic extension of APS. Here we will introduce a[r]

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Energy Vector and Time Vector in the Dirac Theory

Energy Vector and Time Vector in the Dirac Theory

The energy vector in the Dirac theory has come when we would try to show the analogy between sign of helicity and the sign of energy, which we have then called sign of enginity. This energy vector need time vector whose components deserve physical senses.

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Compact Hermitian operators on projective tensor
              products of Banach algebras

Compact Hermitian operators on projective tensor products of Banach algebras

Let U and V be, respectively, an infinite- and a finite-dimensional complex Banach algebras, and let U⊗ p V be their projective tensor product. We prove that (i) every compact Hermitian operator T 1 on U gives rise to a compact Hermitian operator T on U ⊗ p V having the properties that T 1 = T and sp(T 1 ) = sp(T ); (ii) if U and V are separable and U has Hermitian approximation property (HAP), then U ⊗ p V is also separable and has HAP; (iii) every compact analytic semigroup (CAS) on U induces the existence of a CAS on U⊗ p V having some nice properties. In addition, the converse of the above results are discussed and some open problems are posed.
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