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Georges Lemaître was born in 1894 in Charleroi, a mining city in the south of Belgium. He would be followed by his brothers Jacques, Maurice and finally André, who died at a very early age. The Lemaître family were a product of their times: the father, Joseph had studied Law at the University of Louvain and owned a glass-producing factory. The mother, Marguerite, a brewer’s daughter had a friendly and decisive nature.
“Yo era un chico alegre y comunicativo, que no mostraba ninguna inclinación especial por nada, aunque poco a poco empezaba a destacar en Matemáticas, Física, Química e Historia”.
“I was a happy and talkative child, not especially keen on anything, although bit by bit
I began to stand out in Mathematics, Physics, Chemistry and History.”
I began to stand out in Mathematics, Physics, Chemistry and History.”
2. Cambio de rumbo / A change in direction
Al estallar la Primera Guerra Mundial, Georges y Jacques Lemaître se alistaron como voluntarios. En el frente vivieron momentos trágicos: multitud de soldados morían en una guerra absurda. Al terminar la contienda, dejó la Escuela de Ingenieros y siguió los estudios de Física y Matemáticas. Acto seguido ingresó en el seminario de Malinas, donde compatibilizaba su preparación para el sacerdocio con el estudió la teoría de la relatividad.
At the outbreak of World War I, Georges and Jacques enlisted voluntarily. They witnessed much tragedy at the front: countless numbers of lives were lost in an absurd war. The conflict over, he left the School of Engineering and continued with his studies in Physics and Mathematics. Soon afterwards he entered the seminary at Malinas, where he devoted his time to both preparing for the priesthood as well as studying the theory of relativity.
“Nuestro proyecto inicial era dar un paseo en bicicleta por el Tirol,
pero los acontecimientos de agosto de 1914 cambiaron todos nuestros planes,
pues partimos a la guerra, en bicicleta… para acabar en la artillería”.
“Our original plan was to do a biking tour of the Tirol, but the events of August 1914
changed all our arrangements, so we set off to war on our bikes…
changed all our arrangements, so we set off to war on our bikes…
to end up fighting in the artillery.”
3. Becas de investigación / Research grants
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At Cambridge University, Lemaître struck up a keen relationship with Eddington, one of the top scientists around at the time. He taught Lemaître to combine astronomy with the theory of relativity. When he arrived at Harvard, he learned how to measure distances in the universe, using luminous variable stars called cepheids, as beacons. Then, at the Mount Wilson Observatory, Hubble showed him that the universe was formed by galaxies and that it was much bigger than people thought. In Arizona, Lemaître visited Vesto Slipher, who for more than a decade had observed the redshift of the galaxies, which had not been explained. Apart from all this, at the Massachusetts Institute of Technology, he started his doctorate.
“Llegué a Norteamérica cuando las observaciones astronómicas comenzaban
a cambiar la idea que teníamos del universo”.
“I arrived in the States at a time when astronomical observation was beginning to change the idea people had of the universe.”
4. El universo en expansión / An expanding universe
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El físico y matemático ruso, Alexander Friedmann, propuso entre 1922 y 1924 varias soluciones posibles para la historia del universo, que eran de tipo dinámico (universo en expansión, contracción u oscilante), y que contrastaban con el universo estático preferido por Einstein. Friedmann murió en 1925.
Lemaître combined his acquired knowledge and solved the equations pertaining to the theory of general relativity, which thus explained the universe as a whole. An intermediate cosmological model between that of Einstein (static) and that of De Sitter (vacuum): a universe of spherical symmetry, eternal and in evolution. The beginning of the universe would be lost in an infinitely distant past, under the supposition that expansion took place very slowly as a consequence of the forces of attraction and repulsion being practically compensated. Later, the repelling force had to overcome gravitational attraction, leading to an exponential growth, which is the situation in which we find ourselves at the moment.
The Russian physicist and mathematician Alexander Friedmann proposed, between 1922 and 1924, several possible solutions for the history of the universe which were dynamic (expanding, contracting or oscillating universe), and that contrasted with the static universe preferred by Einstein. Friedmann died in 1925.
The Russian physicist and mathematician Alexander Friedmann proposed, between 1922 and 1924, several possible solutions for the history of the universe which were dynamic (expanding, contracting or oscillating universe), and that contrasted with the static universe preferred by Einstein. Friedmann died in 1925.
“Iba buscando una solución que no solamente fuera compatible con las matemáticas,
sino también con la física, al dar explicación a las observaciones astronómicas”.
sino también con la física, al dar explicación a las observaciones astronómicas”.
“I was seeking a solution that would not only be compatible with mathematics,
but also with physics, whilst explaining astronomical observation.”
but also with physics, whilst explaining astronomical observation.”
5. El día sin ayer / The day without yesterday
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Eddington y Einstein, que habían apoyado la idea de un universo en expansión, fueron escépticos respecto a esta nueva propuesta de Lemaître que iba más allá de la simple expansión del universo en el presente para retroceder hasta su origen.
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“… podemos concebir el comienzo del universo como un único átomo, cuyo peso atómico es la masa de todo el universo. Este átomo altamente inestable se dividiría en átomos más y más pequeños por una especie de proceso super-radiactivo”.
“… we could conceive the beginning of the universe in the form of a single atom, the atomic weight of which is the total mass of the universe. This highly unstable atom would divide up into smaller and smaller atoms by a kind of super-radio-active process.”
6. Los rayos cósmicos / Cosmic rays
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On his second journey to the USA and motivated by a mutual interest in cosmic rays, he got in contact with a Mexican scientist, Manuel Sandoval Vallarta, at MIT. Sandoval had studied Mathematics and Physics. They immersed themselves in their work in the hope that the rays would constitute an echo of the original explosion of the universe. They also were able to count on the help of several disciples, especially André Deprit and Odon Godart.
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“Our universe bears the marks of youth and we can hope to reconstruct its story. […].One of the most curious hieroglyphs in our astronomical library is the ultra penetrating radiation; cosmic rays. Can we fix its date? Can we read it?”
7. Frente a otra teoría / In the face of another theory
En 1946 Lemaître publica el libro que reúne todo su pensamiento sobre la hipótesis del átomo primitivo. George Gamow -discípulo de Friedmann- toma el testigo de la teoría del Big Bang.
Como consecuencia de que la hipótesis del átomo primitivo seguía sin tener una rotunda confirmación experimental que la avalara, surgieron modelos cosmológicos alternativos. Entre ellos, destacó la teoría del estado estacionario, propuesta por Fred Hoyle, Hermann Bondi y Thomas Gold en 1948. Esta proponía la creación continua de materia, consiguiendo que el universo fuera el mismo, tanto en el espacio como en el tiempo.
Como consecuencia de que la hipótesis del átomo primitivo seguía sin tener una rotunda confirmación experimental que la avalara, surgieron modelos cosmológicos alternativos. Entre ellos, destacó la teoría del estado estacionario, propuesta por Fred Hoyle, Hermann Bondi y Thomas Gold en 1948. Esta proponía la creación continua de materia, consiguiendo que el universo fuera el mismo, tanto en el espacio como en el tiempo.
In 1946 Lemaître publishes the book in which he compiles all his theories on the primeval atom.
Georges Gamow -disciple of Friedmann- adopts Lemaître’s “Big Bang” theory.
Since the primitive atom hypothesis had no sound experimental evidence to back it up, alternative cosmological models began to emerge. Among them, the one that most stood out was the Steady State theory, proposed by Fred Hoyle, Hermann Bondi and Thomas Gold in 1948. This theory held that there was a continuous creation of matter, thereby succeeding that the universe remained the same, both in space and in time.
Georges Gamow -disciple of Friedmann- adopts Lemaître’s “Big Bang” theory.
Since the primitive atom hypothesis had no sound experimental evidence to back it up, alternative cosmological models began to emerge. Among them, the one that most stood out was the Steady State theory, proposed by Fred Hoyle, Hermann Bondi and Thomas Gold in 1948. This theory held that there was a continuous creation of matter, thereby succeeding that the universe remained the same, both in space and in time.
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“Quizás esta hipótesis [del átomo primitivo] les parezca poco científica. Todavía no está establecida con certeza. […]. Todo esto es hipotético, pero todo ello es científico, porque todo, aunque no probado aún, es susceptible de serlo, de ser confirmado experimentalmente”.
“You may think that this hypothesis [of the primeval atom] is not very scientific. It is not yet securely established. […]. All this is hypothetical, but it is all scientific, because all, even though not proven yet, all is susceptible of proof, of experimental confirmation.”
Arno Penzias y Robert Wilson habían descubierto una radiación de microondas, rastro fósil de la gran explosión con que dio comienzo el mundo. Tras su muerte, Lemaître nos ha dejado un ejemplo de honradez intelectual, nos ha abierto el camino para comprender un poco mejor el mundo en el que vivimos: un universo inmensamente grande al que accedemos por el conocimiento de lo extremadamente pequeño, que nos lleva a superar las paradojas de la existencia de un instante físico inicial, rompiendo con la visión estática del cosmos que se tenía hasta ese momento. Y esto fue posible gracias a su sano optimismo; optimismo que tenía su origen en el Dios misterioso y a la vez real en quien depositó su fe y al que tendían sus investigaciones científicas.
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Me interesaba por la verdad desde el punto de vista de la salvación tanto como por la verdad desde el punto de vista de la certeza científica. Me parecía que había dos caminos que conducían a la verdad, y decidí seguir uno y otro”.
“I was interested in the truth from the point of view of salvatio as well as the truth from the point of view of scientific certainty. It seemed to me there were two roads leading to the truth and I decided to follow each one.”