Angel "Java" Lopez en Blog

30 de Julio, 2011

Publicado el 30 de Julio, 2011, 16:17

Ya tomé y comenté algunos datos de la vida de Einstein, tomados de una biografía que tengo, la escrita por Banesh Hoffman. Ver:

Einstein y Planck, primer contacto
Einstein, el "ruso"
La espera de Einstein
Einstein buscando trabajo

Pero hay una biografía que se destaca, especialmente por ser una biografía científica: la de Abraham Pais. Es un excelente libro, pero no es una biografía de "simples hechos". Se interna en el desarrollo del pensamiento de Einstein, explicando sus publicaciones, relaciones con otros científicos y teorías. Hoy encuentro en esa biografía un interesante prólogo de Roger Penrose. Leo:

For Einstein contributed far more to the physics of the early 20th century than just relativity. Apart from Max Planck, with his ground-breaking work of 1900 (on the spectrum of black-body radiation), Einstein was the first to break away from the classical physics of the time and to introduce the crucial quantum "wave/particle" idea—the idea that despite light being an electromagnetic wave, it sometimes had to be treated as a collection of particles (now called "photons"). Through this work Einstein discovered the explanation of the photo-electric effect, this eventually winning him a Nobel Prize. He provided (in his doctorate thesis) a novel method of determining the sizes of molecules, at a time when their very existence was still controversial. He was one of the first to understand the detailed nature of the tiny wiggling "Brownian" motion of small particles in suspension and to provide a beginning to the new statistical physics. He contributed key ideas that led to the development of lasers. And all this is not to mention his revolutionary theories of special and general relativity!

Vean que Einstein termina ganando el premio Nobel por su trabajo sobre la absorción en paquetes de la luz, explicando el efecto fotoeléctrico (el "paper" de 1905 trata mas temas que el efecto fotoeléctrico; tengo que revisar si también trataba la emisión en paquetes). Más adelante, Penrose comenta sobre el caracter de Einstein:

And we find that Einstein was certainly no saint, though he was an admirable man in many ways. It is perhaps not surprising that he had a remarkable faculty for detaching himself from his surroundings, no doubt both a necessary factor for him and a cause of strain in his two marriages. But he certainly did not lack personal feelings, as is made particularly clear in his highly sensitive obituary notices and appreciations of fellow scientists and friends. And he clearly had a sense of humour. He was a humanitarian, a pacifist, and an internationalist. His feelings would, perhaps as often as not, be more directed at humanity as a whole than at particular individuals.

Esto que sigue yo no lo conocía:

He could sometimes be petulant, however, such as after learning that a paper that he submitted to Physical Review had actually been sent to a referee(!), whose lengthy report requested clarifications. Einstein angrily withdrew his paper and never submitted another to that journal.

Muchas veces se olvida que ideas como las de Einstein también fueron planteadas por otros, como Poincare y Hilbert:

And he could feel an understandable human annoyance in matters of priority concerning his own scientific work. Usually he would later check his over-reaction, and in these cases we might have on record only the very gracious subsequent letters of reconciliation to suggest any earlier friction. His correspondence with the renowned mathematician David Hilbert was a case in point, concerning the issue of who had first correctly formulated the full field equations of general relativity. But in the case of another great mathematician, Henri Poincare, in relation to the origins of special relativity, it took until towards the end of Einstein's life for him even to acknowledge the existence of Poincare's contributions. There is little doubt that Einstein had been influenced by Poincare, perhaps indirectly through Lorentz, or through Poincare's popular writings. Poincare himself seems to have been less generous, as he never even mentioned Einstein's contributions at all in his own later papers on the subject!

Debo revisar la historia de Einstein y Hilbert: tengo por ahí parte del texto de Hilbert sobre gravitación y relatividad general (donde recuerdo llega a proponer una primer teoría gauge). El cambio en el trabajo de Einstein hacia la segunda mitad de su vida, también es comentada por Penrose, en base a lo que describe Pais:

It is interesting also to follow the developments in Einstein's approach to physics as he grew older. It is a common view that Einstein slowed down dramatically as he reached his 40s, or that he perhaps lost his earlier extraordinary instincts for divining physical truth. What Pais's account makes clear, however, is that he found himself driven more and more into areas where his own technical judgements were not so reliable. One must bear in mind that although Einstein was an able mathematician, his profound natural gifts lay in physics not mathematics. This comes through particularly in the section of the book on general relativity, where Einstein's struggles are described, starting with his appreciation in 1907 of the fundamenal role of the equivalence principle and ending with his final field equations in 1915. In place of the sureness that Einstein exhibited in his earlier work, now there is vacillation: he is continually saying that he believes that he has found the final form of the theory, only to retract in a few months' time and to present a quite different scheme with equal confidence.

Interesante lo que puntualiza: mientras en sus primeras teorías, Einstein se movía dentro de la seguridad de su intuición física, en su trabajo sobre la unificación de la gravedad y el electromagnetismo no gozó de "lugar firme" donde apoyarse y avanzar. Pueden leer algo sobre la preferencia de Einstein hacia la física en:

Física y Matemáticas, según Einstein

Me gustaría recordar aquí también a la opinión de Einstein sobre matemáticas y realidad:

Einstein: Matemáticas y Realidad

Nos leemos!

Angel "Java" Lopez

Por ajlopez, en: Ciencia