Universidad Central de Venezuela
Facultad de Ciencias
Escuela de Matemática



Daniel Crespin
Software and Research

In English



Version en español



       Portal en español              Homepage in English


Software:

1. Real vs Quantism is an interactive animation that simulates transitions between two stationary states of the hydrogen atom. Continuous transitions of Realism as well as discontinuous jumps of Quantism can be played. All the papers on Realism mentioned below are bundled in this software.

2. Crespin 2.0 Fast Perceptron Trainer, is a freeware that calculates architecture and weights of perceptron neural networks, runs under Windows, has a graphical interface and provides control on the generalization capabilities of the networks it provides.


Papers on Realism: The following five papers on Realism are also bundled with the Real vs Quantism (RvsQ.exe) software package.

1. Realism: A continuous, deterministic and chaotic wave theory of atoms based on Schrödinger self-adjoint operator and the (realistic) flow it defines in the space of Hilbert rays. No use is made of probabilistic interpretation, random jumps, uncertainty principle, wave-particle duality or hidden variables. Provides a considerable simplification of Quantism and has the same eigenvalues. This down-to-earth theory furnishes a natural model of atomic phenomena in agreement with experimental facts. 73 pages.

2. Projective Dynamical Systems and Realism: Operators in Hilbert space define in the associated projective space certain projective dynamical systems and an observable. Systems defined by unitary and by self adjoint operators are considered. Part I studies the finite dimensional cases and Part II discusses infinite dimensional ones. The paper contains the Projective Spectral Theorem (PST), a mathematical result relevant for Realism (see preprint above). PST is to projective dynamics as the usual linear spectral theorem is to linear dynamics. 47 pages.

3. An Introduction to Realism: This elementary introduction to Realism explains 2-level systems. The states, observables and evolution equation are introduced as postulates for general systems and then applied in the 2-level case. Assuming mild physical hypothesis (the Photon Hypothesis) it is shown in detail how to deduce (and interpret) Einstein formula E=hc/(wavelength). Designed mostly for students, results are worked out clearly and various figures facilitate assimilation of new concepts. 32 pages.

4. Manifesto against Quantism: A document that unveils the situation of Physics with regard to Quantism. Of interest for anyone interested in unmasking Quantism and rationalizing Physics as well as other branches of Science affected by Quantum Theory. 2 pages.

5. FAQ Realism vs Quantism: This paper was prepared to be used with (and is part of) the Real vs Quantism software package. Discusses, in the FAQ question-answer style, various basic issues concerning the replacement of Quantism by Realism. The brief sections include:
    Realism and Quantism
    Change and Evolution
    Mathematics of Evolution
    Outline of Realism
    Discussion of Realism
    Sociology of Realism
    History of Realism
    Goals of Realism
Provides a critical view of Quantism and the desirable end of its crooked paradigms. 12 pages.



Papers on Neural Networks:

1. Neural polyhedra: Explicit formulas to express any polyhedron as a three layer perceptron neural network. Useful to calculate directly and without training the architecture and weights of a network that executes a given pattern recognition task. See preprint below. 8 pages.

2. Pattern recognition with untrained perceptrons: Shows how to construct polyhedra directly from given pattern recognition data. The perceptron network associated to these polyhedra (see preprint above) solves the recognition problem. 10 pages.

3. Neural network formalism: Neural networks are defined using only elementary concepts from set theory, without the usual connectionistic graphs. The typical neural diagrams are derived from these definitions. This approach provides mathematical techniques and insight to develop theory and applications of neural networks. 8 pages.

4. Geometry of perceptrons: It is proved that semilinear perceptron networks are products of characteristic maps of polyhedra. This gives insight into the geometric structure of these networks. The result also holds for more general (semialgebraic, etc.) perceptron networks, and suggests a new technique to solve pattern recognition problems. See other preprints in this location and NEUROGON software below. 3 pages.

5. Generalized Backpropagation: Global backpropagation formulas for differentiable neural networks are considered from the viewpoint of minimization of the quadratic error using the gradient method. The gradient of (the quadratic error function of) a processing unit is expressed in terms of the output error and the transposed derivative of the unit with respect to the weight. The gradient of the layer is the product of the gradients of the processing units. The gradient of the network equals the product of the gradients of the layers. Backpropagation provides the desired outputs or targets for the layers. Standard formulas for semilinear networks are deduced as a special case. 14 pages.

6. A Primer on Perceptrons: Basic vocabulary for perceptron neural networks with emphasis on mathematical language. Assumes familiarity with vector spaces and matrices. 7 pages.


Mail to: dcrespin@gmail.com

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