73 research outputs found

    21st Century Ergonomic Education, From Little e to Big E

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    Despite intense efforts, contemporary educational systems are not enabling individuals to function optimally in modern society. The main reason is that reformers are trying to improve systems that are not designed to take advantage of the centuries of history of the development of today's societies. Nor do they recognize the implications of the millions of years of history of life on earth in which humans are the latest edition of learning organisms. The contemporary educational paradigm of "education for all" is based on a 17th century model of "printing minds" for passing on static knowledge. This characterizes most of K-12 education. In contrast, 21st Century education demands a new paradigm, which we call Ergonomic Education. This is an education system that is designed to fit the students of any age instead of forcing the students to fit the education system. It takes into account in a fundamental way what students want to learn -- the concept "wanting to learn" refers to the innate ability and desire to learn that is characteristic of humans. The Ergonomic Education paradigm shifts to education based on coaching students as human beings who are hungry for productive learning throughout their lives from their very earliest days.Comment: plain latex, 13 pages, 1 tabl

    Small x divergences in the Similarity RG approach to LF QCD

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    We study small x divergences in boost invariant similarity renormalization group approach to light-front QCD in a heavy quark-antiquark state. With the boost invariance maintained, the infrared divergences do not cancel out in the physical states, contrary to previous studies where boost invariance was violated by a choice of a renormalization scale. This may be an indication that the zero mode, or nontrivial light-cone vacuum structure, might be important for recovering full Lorentz invariance.Comment: 23 pgs, 1 fig. Revised for publication: typos corrected, improved discussion of regularizatio

    Renormalization of Schr\"odinger Equation and Wave Functional for Rapidly Oscillating Fields in QCD

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    Background field method is used to perform renormalization group transformations for Schr\"odinger equation in QCD. The dependence of the ground state wave functional on rapidly oscillating fields is found.Comment: 8pp., Late

    A Density Matrix Renormalization Group Approach to an Asymptotically Free Model with Bound States

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    We apply the DMRG method to the 2 dimensional delta function potential which is a simple quantum mechanical model with asymptotic freedom and formation of bound states. The system block and the environment block of the DMRG contain the low energy and high energy degrees of freedom, respectively. The ground state energy and the lowest excited states are obtained with very high accuracy. We compare the DMRG method with the Similarity RG method and propose its generalization to field theoretical models in high energy physics.Comment: REVTEX file, 4 pages, 1 Table, 3 eps Figures. Explanation on the extension to many-body QFT problems added, 3 new references and some minor changes. New forma

    Nonperturbative renormalization in a scalar model within Light-Front Dynamics

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    Within the covariant formulation of Light-Front Dynamics, in a scalar model with the interaction Hamiltonian H=gψ2(x)ϕ(x)H=-g\psi^{2}(x)\phi(x), we calculate nonperturbatively the renormalized state vector of a scalar "nucleon" in a truncated Fock space containing the NN, NπN\pi and NππN\pi\pi sectors. The model gives a simple example of non-perturbative renormalization which is carried out numerically. Though the mass renormalization δm2\delta m^2 diverges logarithmically with the cutoff LL, the Fock components of the "physical" nucleon are stable when LL\to\infty.Comment: 22 pages, 5 figure

    Renormalization of Tamm-Dancoff Integral Equations

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    During the last few years, interest has arisen in using light-front Tamm-Dancoff field theory to describe relativistic bound states for theories such as QCD. Unfortunately, difficult renormalization problems stand in the way. We introduce a general, non-perturbative approach to renormalization that is well suited for the ultraviolet and, presumably, the infrared divergences found in these systems. We reexpress the renormalization problem in terms of a set of coupled inhomogeneous integral equations, the ``counterterm equation.'' The solution of this equation provides a kernel for the Tamm-Dancoff integral equations which generates states that are independent of any cutoffs. We also introduce a Rayleigh-Ritz approach to numerical solution of the counterterm equation. Using our approach to renormalization, we examine several ultraviolet divergent models. Finally, we use the Rayleigh-Ritz approach to find the counterterms in terms of allowed operators of a theory.Comment: 19 pages, OHSTPY-HEP-T-92-01

    Pseudo-nearrings and quasi-modules over them

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    In this paper we start to investigate a new notion of pseudo-nearrings and a generalization of linear spaces to quasi-modules over pseudo-nearrings. Pseudo-nearrings can be treated as ringoids in the sense of J. Hion (see [6]). The idea of pseudo-nearings is based on the notion of a ∗-associative quasigroup, i.e. on an involutive groupoid (A;+,* ) in which the following identities hold: (x*)* = x, (x + y)* = y* + x*, (x + y)* + z = x + (y + z)*. We assume also commutativity and quasigroup properties of (A;+)

    Associative polynomial functions over bounded distributive lattices

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    The associativity property, usually defined for binary functions, can be generalized to functions of a given fixed arity n>=1 as well as to functions of multiple arities. In this paper, we investigate these two generalizations in the case of polynomial functions over bounded distributive lattices and present explicit descriptions of the corresponding associative functions. We also show that, in this case, both generalizations of associativity are essentially the same.Comment: Final versio

    Mesons in (2+1) Dimensional Light Front QCD. II. Similarity Renormalization Approach

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    Recently we have studied the Bloch effective Hamiltonian approach to bound states in 2+1 dimensional gauge theories. Numerical calculations were carried out to investigate the vanishing energy denominator problem. In this work we study similarity renormalization approach to the same problem. By performing analytical calculations with a step function form for the similarity factor, we show that in addition to curing the vanishing energy denominator problem, similarity approach generates linear confining interaction for large transverse separations. However, for large longitudinal separations, the generated interaction grows only as the square root of the longitudinal separation and hence produces violations of rotational symmetry in the spectrum. We carry out numerical studies in the G{\l}azek-Wilson and Wegner formalisms and present low lying eigenvalues and wavefunctions. We investigate the sensitivity of the spectra to various parameterizations of the similarity factor and other parameters of the effective Hamiltonian, especially the scale σ\sigma. Our results illustrate the need for higher order calculations of the effective Hamiltonian in the similarity renormalization scheme.Comment: 31 pages, 4 figures, to be published in Physical Review

    Perturbative Tamm-Dancoff Renormalization

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    A new two-step renormalization procedure is proposed. In the first step, the effects of high-energy states are considered in the conventional (Feynman) perturbation theory. In the second step, the coupling to many-body states is eliminated by a similarity transformation. The resultant effective Hamiltonian contains only interactions which do not change particle number. It is subject to numerical diagonalization. We apply the general procedure to a simple example for the purpose of illustration.Comment: 20 pages, RevTeX, 10 figure
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