Related papers: Comment on Dirac spectral sum rules for QCD_3
New relations between QCD Borel sum rules for masses of Sigma^0 and Lambda hyperons are constructed. It is shown that starting from the sum rule for the Sigma^0 hyperon mass it is straightforward to obtain the corresponding sum rule for the…
We find clear numerical evidence for a bilinear condensate in three-dimensional QCD in the 't Hooft limit. We use a non-chiral random matrix model to extract the value of the condensate $\Sigma$ from the low-lying eigenvalues of the…
Apparent inconsistencies between different formulations of nucleon sum rules at finite density are resolved through a proper accounting of asymmetries in the spectral functions between positive- and negative-energy states.
In this article, we extend our previous work to study the $\Sigma$-type heavy baryons $\Sigma_c$ and $\Sigma_b$ in the nuclear matter using the QCD sum rules, and obtain three coupled QCD sum rules for the masses $M_{\Sigma_Q}^*$, vector…
QCD finite energy sum rules, together with the latest updated ALEPH data on hadronic decays of the tau-lepton are used in order to determine the vacuum condensates of dimension $d=2$ and $d=4$. These data are also used to check the validity…
The ALEPH data on the vector and axial-vector spectral functions, extracted from tau-lepton decays is used in order to test local and global duality, as well as a set of four QCD chiral sum rules. These are the Das-Mathur-Okubo sum rule,…
A sum rule relating the widths of the decays of mesons belonging to heavy quark multiplets, having the same parity and light quark spin j, into the low lying $0^-$ and $1^-$ multiplet is obtained. As this sum rule follows from properties of…
Extending earlier work of Killip-Simon and Simon-Zlatos, we obtain sum rules for Jacobi matrices in which the a.c. part of the spectral measure and the eigenvalues of the matrix appear on opposite sides of the equation. We use these to…
We derive explicit expressions for the sum rules of the eigenvalues of inhomogeneous strings with arbitrary density and with different boundary conditions. We show that the sum rule of order $N$ may be obtained in terms of a diagrammatic…
Let $$L_0=\suml_{j=1}^nM_j^0D_j+M_0^0,\,\,\,\,D_j=\frac{1}{i}\frac{\pa}{\paxj}, \quad x\in\Rn,$$ be a constant coefficient first-order partial differential system, where the matrices $M_j^0$ are Hermitian. It is assumed that the homogeneous…
We consider the parity-invariant Dirac operator with a mass term in three-dimensional QCD for $N_c=2$ and quarks in the fundamental representation. We show that there exists a basis in which the matrix elements of the Euclidean Dirac…
We calculate the on-shell $\Sigma^0$-$\Lambda$ mixing parameter $\theta$ with the method of QCD sum rule. Our result is $\theta (m^2_{\Sigma^0}) =(-)(0.5\pm 0.1)$MeV. The electromagnetic interaction is not included.
We propose a phenomenological QCD sum rule with an explicit diquark field to investigate the essential ingredients inside the hadrons. Introducing the mass (m_\phi) and the condensate (\phi^2) for the diquark field as parameters in the…
We derive two sum rules by studying the low energy Compton scattering on a target of arbitrary (nonzero) spin j. In the first sum rule, we consider the possibility that the intermediate state in the scattering can have spin |j \pm 1| and…
We derive constraints on the asymmetry a1 of the momentum fractions carried by quark and antiquark in K and K* mesons in leading twist. These constraints follow from exact operator identities and relate a1 to SU(3) breaking…
Borel transformed QCD sum rules conventionally use a real valued parameter (the Borel mass) for specifying the exponential weight over which hadronic spectral functions are averaged. In this paper, it is shown that the Borel mass can be…
Exact results from random matrix theory are used to systematically analyse the relationship between microscopic Dirac spectra and finite-volume partition functions. Results are presented for the unitary ensemble, and the chiral analogs of…
In these lectures we review recent results on universal fluctuations of QCD Dirac spectra and applications of Random Matrix Theory (RMT) to QCD. We review general properties of Dirac spectra and discuss the relation between chiral symmetry…
The spectral function $\rho_{V-A}(s)$ is determined from ALEPH and OPAL data on hadronic tau decays using a neural network parametrization trained to retain the full experimental information on errors, their correlations and chiral sum…
We have obtained explicit integral expressions for the sums of inverse powers of the eigenvalues of the Laplacian on a unit sphere, in presence of an arbitrary variable density. The exact expressions for the sum rules are obtained by…