14,926 research outputs found

    Baryon Self-Energy With QQQ Bethe-Salpeter Dynamics In The Non-Perturbative QCD Regime: n-p Mass Difference

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    A qqq BSE formalism based on DB{\chi}S of an input 4-fermion Lagrangian of `current' u,d quarks interacting pairwise via gluon-exchange-propagator in its {\it non-perturbative} regime, is employed for the calculation of baryon self-energy via quark-loop integrals. To that end the baryon-qqq vertex function is derived under Covariant Instantaneity Ansatz (CIA), using Green's function techniques. This is a 3-body extension of an earlier q{\bar q} (2-body) result on the exact 3D-4D interconnection for the respective BS wave functions under 3D kernel support, precalibrated to both q{\bar q} and qqq spectra plus other observables. The quark loop integrals for the neutron (n) - proton (p) mass difference receive contributions from : i) the strong SU(2) effect arising from the d-u mass difference (4 MeV); ii) the e.m. effect of the respective quark charges. The resultant n-p difference comes dominantly from d-u effect (+1.71 Mev), which is mildly offset by e.m.effect (-0.44), subject to gauge corrections. To that end, a general method for QED gauge corrections to an arbitrary momentum dependent vertex function is outlined, and on on a proportionate basis from the (two-body) kaon case, the net n-p difference works out at just above 1 MeV. A critical comparison is given with QCD sum rules results.Comment: be 27 pages, Latex file, and to be published in IJMPA, Vol 1

    Design of doubly-complementary IIR digital filters using a single complex allpass filter, with multirate applications

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    It is shown that a large class of real-coefficient doubly-complementary IIR transfer function pairs can be implemented by means of a single complex allpass filter. For a real input sequence, the real part of the output sequence corresponds to the output of one of the transfer functions G(z) (for example, lowpass), whereas the imaginary part of the output sequence corresponds to its "complementary" filter H(z)(for example, highpass). The resulting implementation is structurally lossless, and hence the implementations of G(z) and H(z) have very low passband sensitivity. Numerical design examples are included, and a typical numerical example shows that the new implementation with 4 bits per multiplier is considerably better than a direct form implementation with 9 bits per multiplier. Multirate filter bank applications (quadrature mirror filtering) are outlined

    Scattering of Electron from Five Dimensional Wave Equation

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    The solution of the radial part of the five dimensional Wave equal ion for the case o f scattering of an electron in a Coulomb field has been considered and it is found that half integral quantum numbers appear in the solution which lends supports to the idea that the influence of the fifth coordinate is somewhat analogue to the existence of the spin

    Experimental Test of Quantum No-Hiding Theorem

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    Linearity and unitarity are two fundamental tenets of quantum theory. Any consequence that follows from these must be respected in the quantum world. The no-cloning theorem and the no-deleting theorem are the consequences of the linearity and the unitarity. Together with the stronger no-cloning theorem they provide permanence to quantum information, thus, suggesting that in the quantum world information can neither be created nor be destroyed. In this sense quantum information is robust, but at the same time it is also fragile because any interaction with the environment may lead to loss of information. Recently, another fundamental theorem was proved, namely, the no-hiding theorem that addresses precisely the issue of information loss. It says that if any physical process leads to bleaching of quantum information from the original system, then it must reside in the rest of the universe with no information being hidden in the correlation between these two subsystems. This has applications in quantum teleportation, state randomization, private quantum channels, thermalization and black hole evaporation. Here, we report experimental test of the no-hiding theorem with the technique of nuclear magnetic resonance (NMR). We use the quantum state randomization of a qubit as one example of the bleaching process and show that the missing information can be fully recovered up to local unitary transformations in the ancilla qubits. Since NMR offers a way to test fundamental predictions of quantum theory using coherent control of quantum mechanical nuclear spin states, our experiment is a step forward in this direction.Comment: 12 pages, 6 Figs. Jharana Rani Samal, Deceased on her 27th birthday 12th Nov. 2009. The experimental work of this paper was completely carried out by the first author. We dedicate this paper to the memory of the brilliant soul of Ms. Jharana Rani Samal

    On the Maximum Energy Release from Formation of Static Compact Objects

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    Type II Supernova 1987A (SN 1987A), observed in 1987, released an energy of \mbox{Q3×1053Q \approx 3 \times 10^{53} erg}}. This huge energy is essentially the magnitude of gravitational potential or self-gravitational energy (PE) of a new born cold neutron star having a gravitational compactness or redshift zb0.15z_b \approx 0.15. One may wonder what could be the upper limit on the amount of energy that might be released with the formation of a cold Ultra Compact Object (UCO) with an arbitrary high zbz_b. Accordingly, here, for the first time, we obtain an analytical expression for the PE of a homogeneous general relativistic UCO assuming it to be cold and static. It is found that the PE of a homogeneous UCO of mass MM may exceed Mc2^2 and be as large as 1.34 Mc2^2. This result, though surprising, follows from an \textit{exact and correct} analytical calculation based on the standard General Theory of Relativity (GTR). Further, UCOs supported by tangential stresses may be inhomogeneous and much more massive than neutron stars with PE \sim 2.1 Mc2^2 Thus, in principle, formation of an UCO of a few solar masses (MM_\odot) might release an energy Q1055Q\sim10^{55} erg.Comment: 8 Pages, 1 Figure, Galaxies 2023, 11, 11

    Tree-structured complementary filter banks using all-pass sections

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    Tree-structured complementary filter banks are developed with transfer functions that are simultaneously all-pass complementary and power complementary. Using a formulation based on unitary transforms and all-pass functions, we obtain analysis and synthesis filter banks which are related through a transposition operation, such that the cascade of analysis and synthesis filter banks achieves an all-pass function. The simplest structure is obtained using a Hadamard transform, which is shown to correspond to a binary tree structure. Tree structures can be generated for a variety of other unitary transforms as well. In addition, given a tree-structured filter bank where the number of bands is a power of two, simple methods are developed to generate complementary filter banks with an arbitrary number of channels, which retain the transpose relationship between analysis and synthesis banks, and allow for any combination of bandwidths. The structural properties of the filter banks are illustrated with design examples, and multirate applications are outlined

    Giant Magneto-Impedance Behaviour in Ferro-Magnetic Materials

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    The ferromagnetic amorphous and nanocrystalhne materials exhibited a new phenomenon called Giant magneto-impedance (GMI). In this phenomenon these materials exhibited a sensitive change in an AC voltage with the application of a small DC magnetic field. GUI properties were investi-gated for four different compositions of amorphous and nanocrystalline ferromagnetic alloys for ribbon and wire samples. The impedance behaviour was strongly affected by magnetostriction of the materials. In nearly zero magneto-strictive amorphous wires about 100% change per Oe of mag-netic field was observed
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