Angel "Java" Lopez en Blog

Mayo del 2020


Publicado el 31 de Mayo, 2020, 18:00

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Coronavirus and Flu
https://www.nytimes.com/2020/02/29/health/coronavirus-flu.html

Spreading the Word on a Possible Alzheimer’s Treatment
https://www.quantamagazine.org/stimulated-brain-waves-offer-a-possible-treatment-for-alzheimers-20200527/

Black Hole Paradoxes Reveal a Fundamental Link Between Energy and Order
https://www.quantamagazine.org/black-hole-paradoxes-reveal-a-fundamental-link-between-energy-and-order-20200528/

Proxima Centauri Exoplanet
https://twitter.com/johncarlosbaez/status/1266428654721961984

Integrated Information in Process Theories
https://arxiv.org/abs/2002.07654

Particle Quiz
https://scoollab.web.cern.ch/sites/scoollab.web.cern.ch/files/ParticleGame/

How to Desing a Perpetual Energy Machine
https://www.quantamagazine.org/how-to-design-a-perpetual-energy-machine-20200401/

Epidemic Modeling 101: Or why your CoVID-19 exponential fits are wrong
https://medium.com/data-for-science/epidemic-modeling-101-or-why-your-covid19-exponential-fits-are-wrong-97aa50c55f8

Nos leemos!

Angel "Java" Lopez
http://www.ajlopez.com
http://twitter.com/ajlopez

Por ajlopez, en: Ciencia

Publicado el 30 de Mayo, 2020, 13:18

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Triángulo y Circunferencia Circunscrita
https://www.gaussianos.com/triangulo-y-circunferencia-circunscrita/

Mathematician Measures the Repulsive Force Within Polynomials
https://www.quantamagazine.org/new-math-measures-the-repulsive-force-within-polynomials-20200514/

Isbell duality
https://twitter.com/johncarlosbaez/status/1266029338190680064

Put coplay / lens update into a state monad where the state variable is a payoff vector
https://twitter.com/_julesh_/status/1251507999606276104

Kurt Gödel Wanted to Revise Our Concept of Time
https://www.thegreatcoursesdaily.com/kurt-godel-wanted-to-revise-our-concept-of-time/

Highly composite numbers
http://wwwhomes.uni-bielefeld.de/achim/highly.html

Symbolic Mathematics Finally Yields to Neural Networks
https://www.quantamagazine.org/symbolic-mathematics-finally-yields-to-neural-networks-20200520/

Graduate Student Solves Decades-Old Conway Knot Problem
https://www.quantamagazine.org/graduate-student-solves-decades-old-conway-knot-problem-20200519/

Nos leemos!

Angel "Java" Lopez
http://www.ajlopez.com
https://twitter.com/ajlopez

Publicado el 25 de Mayo, 2020, 15:07

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Los conceptos de campo, partícula, partícula virtual y vacío
https://francis.naukas.com/2012/08/15/los-conceptos-de-campo-particula-particula-virtual-y-vacio/

Así inactivan el coronavirus los productos de limpieza
https://www.lasexta.com/el-muro/deborah-garcia/asi-inactivan-coronavirus-productos-limpieza_202003185e71f764cf7ab300010f99cc.html

What Other Coronaviruses Tell Us About SARS-CoV-2
https://www.quantamagazine.org/what-can-other-coronaviruses-tell-us-about-sars-cov-2-20200429/

Study: Could dark matter be hiding in existing data?
https://phys.org/news/2020-05-dark.html

Physicists have just seen "Pauli crystals"
https://twitter.com/johncarlosbaez/status/1263128844850081792

The Great Debate of Shapley and Curtis — 100 years later
https://astronomy.com/news/2020/04/the-great-debate-of-shapley-and-curtis--100-years-later

Physicists identify unique signature to confirm quark-gluon plasma in Universe
https://arstechnica.com/science/2020/05/physicists-identify-unique-signature-to-confirm-quark-gluon-plasma-in-universe/

Sugary Camouflage on Coronavirus Offers Vaccine Clues
https://www.quantamagazine.org/sugars-on-coronavirus-spike-protein-offer-vaccine-clues-20200505/

Nos leemos!

Angel "Java" Lopez
http://www.ajlopez.com
http://twitter.com/ajlopez

Por ajlopez, en: Ciencia

Publicado el 24 de Mayo, 2020, 11:44

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The role of voting intention in public opinion polarization
https://arxiv.org/abs/1909.07092

Mirth programming language
https://twitter.com/typeswitch/status/1249368983729471488
https://github.com/mirth-lang/mirth

Rule 110
https://en.wikipedia.org/wiki/Rule_110

The Computer Scientist Who Can"t Stop Telling Stories
https://www.quantamagazine.org/computer-scientist-donald-knuth-cant-stop-telling-stories-20200416/

Bourbaki's final perfected definition of the number 1, printed out on paper, would be 200,000 as massive as the Milky Way!
https://twitter.com/johncarlosbaez/status/1250868989414137857

Math3ma
https://www.math3ma.com/

The Mathematics of Privacy
https://becominghuman.ai/the-mathematics-of-privacy-361742827f08

Reflections on monadic lenses
http://www.cs.ox.ac.uk/jeremy.gibbons/publications/mlenses.pdf

Nos leemos!

Angel "Java" Lopez
http://www.ajlopez.com
https://twitter.com/ajlopez

Publicado el 23 de Mayo, 2020, 12:28

En estos días vuelvo a leer a Max Jammer, a quien mencioné en:

Uhlenbeck, Goudsmit y el spin del electron
Max Jammer y el Formalismo de la Mecánica Cuántica

Estoy leyendo su excelente libro "The Conceptual Development of Quantum Mechanics", edición 1966. Leo:

It is the purpose of this study to trace the conceptual development of  quantum mechanics from its inception to its formulation as a full-fledged theory of atomic physics, from its status as a rather doubtful ad hoc hypothesis to that of an imposing intellectual structure of great beauty.

Trata de la mecánica cuántica no relativista de una cantidad finite de grados de libertad, que abarca los primeros desarrollos exitoso, digamos, hasta parte de la tercera década del siglo XX. Las primeras preguntas que nos aparecen son: ¿qué es el desarrollo conceptual? ¿es necesario en este tema?.

All the great theories in the history of physics—from Aristotelian mechanics and its medieval elaborations, through Newtonian dynamics with its Lagrangian or Hamiltonian modifications, to Maxwellian  electrodynamics and* Einsteinian relativity—have been subjected repeatedly to historico-critical investigations, and their conceptual foundations have been thoroughly analyzed. But no comprehensive scholarly study of the conceptual development of quantum mechanics has heretofore appeared. The popular or semiscientific publications available hardly skim the surface of the subject. And the few, though important, essays on the topic written by the originators of the theory themselves are mostly confined to a  particular aspect or to the defense of a specific philosophical position. The publication of a comprehensive and coherent analysis of the conceptual development of quantum mechanics, the only consistent theory of atomic processes, and hence a foundation of modern science, seems therefore to fill an important lacuna in the literature on the history and philosophy of physics.

Primero, es un libro sobre el desarrollo de las ideas. No es un libro de texto para APRENDER mecánica cuántica, sino para entender cómo se fue desarrollando. Por otro lado, no es un libro solamente con el desarrollo histórico: habrá ocasiones donde Jammer se concentra en el desarrollo de una idea, sin importar que ese desarrollo se superponga en años históricos con otro desarrollo de otra idea.

Such a study, however, should not be regarded as an end in itself. Never before has a theory been treated in so many excellent texts within so short a period of time. Since every additional text, as is natural in a developing branch of science, attempts to construct the theory on the basis of an ever more concise logical structure, the traditional texts presenting the material in the order of its historical development are gradually losing ground. Students, it is rightfully claimed, may be saved much trouble "if they are not led through all the historical pitfalls, and instead acquainted from the very beginning with concepts, such as the spin, that cannot be grasped except by quantum mechanical means." [cita 1] Admittedly, a good working knowledge, even a high standard of efficiency and competence in applying the theory to physical problems may be obtained by this method of instruction. But as long as it is true that "however far the phenomena transcend the scope of classical physical explanation, the account of all evidence must be expressed in classical terms," [cita 2] a profound comprehension of quantum mechanics requires more than a study of the subject in its shortest possible logical formulation. "It is impossible to understand the methods of modern quantum mechanics without a knowledge of the way in which the theory has been developing." [cita 3] Indeed, some knowledge of the dramatic struggle of ideas that preceded the formation of quantum  conceptions and of the intricate ways of reasoning that led to the generally accepted formulation of the theory is indispensable for a profound comprehension of its physical significance, for an intelligent appreciation of its philosophical implications, and even for an enlightened understanding of its logical structure. Duhem's statement "faire l'histoire d'un principe physique, c'est en meme temps en faire l'analyse logique" is particularly meaningful for the science of quantum mechanics.

Hoy aprendemos física clásica, digamos la mecánica newtoniana, sin estudiar ni su desarrollo histórico ni conceptual (¿cómo surgió el concepto de energía? ¿y el de momento angular?). Pero en cuántica, y en especial en mecánica cuántica, pasa que si bien se puede aprenderla sin necesitar de la historia o el desarrollo, sus conceptos, operaciones y formalismos son tan extraños a la intuición que para realmente comprenderla, atraparla en su esencia, puede que no haya otro camino que el emprendido por Jammer: el desarrollo de las ideas, para explicar fenómenos que no cuajan en el marco "clásico". Es cierto que hay muy buenos libros para comenzar a entender la mecánica cuántica (y luego la física cuántica) desde algunos principios, sin tener que seguir todo el desarrollo ni histórico ni conceptual. Pero es como que se pierde algo. Un excelente libro que recuerdo ahora, que sigue un desarrollo histórico, más que conceptual, es el Física Cuántica, de Eisberg y Resnick, que era un clásico en mis días de estudiante universitario.

La cita 1 es F.A.Kaempffer, Concepts in Quantum Mechanics. La cita 2 es de Niels Bohr, "Discussion with Einstein on epistemological problems in atomic physics". La cita 3 es A.March, Quantum Mechanics of Particles and Wave Fields.

Seguiré citando y comentando algunos temas de este libro. Es interesante, por ejemplo, cómo plantea que los desarrollos de Jordan y de Dirac, a partir de 1925, son como un contrapunto: mientras el primero se concentra en teorías de campo, el segundo prefirió una vision desde el modelo de partículas.

Nos leemos!

Angel "Java" Lopez
http://www.ajlopez.com
https://twitter.com/ajlopez

Por ajlopez, en: Ciencia

Publicado el 17 de Mayo, 2020, 10:02

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MIP*=RE
https://arxiv.org/abs/2001.04383

A simulation of sunflower growth
https://twitter.com/ZenoRogue/status/1247900522905886723

To Win This Numbers Game, Learn to Avoid Math Patterns
https://www.quantamagazine.org/to-win-this-numbers-game-learn-to-avoid-math-patterns-20200507/

In Star Trek Discovery we heard about the "Logic Extremists"
https://twitter.com/johncarlosbaez/status/1258475087704895488

What does "birational equivalence" mean in a cryptographic context?
https://crypto.stackexchange.com/questions/43013/what-does-birational-equivalence-mean-in-a-cryptographic-context

If you view any ellipse from just the right distance, it will *always* occupy 90 degrees
https://twitter.com/gregeganSF/status/1243318369983418368

Here"s the axioms for a group in strings
https://twitter.com/CreeepyJoe/status/1248736658612031488

Modeling Opinion Dynamics: Theoretical analysis and continuous approximation
https://arxiv.org/abs/1606.00662

Nos leemos!

Angel "Java" Lopez
http://www.ajlopez.com
https://twitter.com/ajlopez

Publicado el 10 de Mayo, 2020, 13:21

Por estos lares seguimos en cuarentena. Mucho trabajo y estudio, pero pudo escribir poco. Repaso de las resoluciones del mes pasado:

- Escribir sobre Matemáticas [pendiente]
- Escribir sobre Física [pendiente]
- Escribir sobre Historia de las Matemáticas [pendiente]
- Escribir sobre Historia de la Ciencia [pendiente]
- Estudiar blues en guitarra [completo]

Tengo que poner voluntad para pasar por escrito lo que estuve aprendiendo de matemáticas y física. Así que sigo insistiendo con estas resoluciones para mayo:

- Escribir sobre Matemáticas
- Escribir sobre Física
- Escribir sobre Historia de las Matemáticas
- Escribir sobre Historia de la Ciencia
- Estudiar blues en guitarra

Angel "Java" Lopez
http://www.ajlopez.com
http://twitter.com/ajlopez

Publicado el 3 de Mayo, 2020, 14:36

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Interface Scaling in the Contact Process
https://arxiv.org/pdf/cond-mat/0003480.pdf

Radical Solutions: Evariste Galois
https://www.damninteresting.com/radical-solutions/

Explicación de teoría de colas y ejercicio resuelto
https://www.youtube.com/watch?v=t3x2KinUqAA&feature=emb_logo

Mathematical proof that rocked number theory will be published
https://www.nature.com/articles/d41586-020-00998-2

Conmutative Semigroups
https://twitter.com/johncarlosbaez/status/1246470112321953792

Quantum Natural Language Processing
https://medium.com/cambridge-quantum-computing/quantum-natural-language-processing-748d6f27b31d
https://github.com/oxford-quantum-group/discopy/blob/ab2b356bd3cad1dfb55ca6606d6c4b4181fe590c/notebooks/qnlp-experiment.ipynb

Graced With Knowledge, Mathematicians Seek to Understand
https://www.quantamagazine.org/mathematicians-grapple-with-sudden-answer-to-connes-embedding-conjecture-20200408/

Landmark Computer Science Proof Cascades Through Physics and Math
https://www.quantamagazine.org/landmark-computer-science-proof-cascades-through-physics-and-math-20200304/

Nos leemos!

Angel "Java" Lopez
http://www.ajlopez.com
https://twitter.com/ajlopez

Publicado el 2 de Mayo, 2020, 17:55

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Conway"s Impact on the Theory of Random Tilings
https://twitter.com/JimPropp/status/1249189041343475712

Ha muerto John Horton Conway (1937-2020) - Gaussianos
https://www.gaussianos.com/ha-muerto-john-horton-conway-1937-2020/

Math After COVID-19
https://www.quantamagazine.org/how-has-coronavirus-affected-mathematics-20200428/

Method of estimating the number of infected people
https://twitter.com/wtgowers/status/1242823142088851456

Tikzcd Editor Category Diagrams
https://tikzcd.yichuanshen.de/

Uncomputable Numbers
https://medium.com/cantors-paradise/uncomputable-numbers-ee528830d295

The Quasi-Stationary Distribution of the Subcritical Contact Process
https://twitter.com/pgroisma/status/1242941761057632257
https://arxiv.org/pdf/1908.04175.pdf

Simulation of quasi-stationary distributions on countable spaces
https://arxiv.org/abs/1206.6712

Nos leemos!

Angel "Java" Lopez
http://www.ajlopez.com
https://twitter.com/ajlopez