Symposion in Memory of George Placzek (1905-1955)
Notice bibliographique
Résumé
There will be two life anniversaries of George Placzek in 2005: that of his birth on 26 September 1905, and that of his passing away on 9 October 1955. Placzek was an outstanding scientist who made substantial contributions to the fields of molecular physics, scattering of light from liquids and gases, the theory of atomic nucleus and the interaction of neutrons with condensed matter. His theory of Raman effect is a pioneering work in the field. Lev Landau and George Placzek derived the Landau-Placzek formula for the ratio of intensities of the Brillouin and the Rayleigh scatterings of light. Hans Bethe and George Placzek provided a fundamental theory of neutron absorption resonances, deriving important laws and selection rules. Papers by Niels Bohr, Rudolf Peierls and George Placzek deal with the theory of nuclear reactions and rank among the classics. The well-known optical theorem bears the names of Bohr, Peierls and Placzek. In a series of experiments, Otto Frisch and Placzek discovered that the absorption of neutrons in matter is strongly dependent upon the atomic mass and the velocity of the neutrons, but for slow neutrons and light elements the neutron-capture cross section is inversely proportional to the velocity. On the eve of the World War II, Placzek was very helpful in formulating the theory of nuclear fission, an example of his many contributions still not properly appreciated. In 1943-1946, he occupied a leading position in the Manhattan Project, forming and later leading its Montreal Theory group in Chalk River. In 1948, he obtained a tenure at the Institute for Advanced Study in Princeton. George Placzek was born in Brno, Moravia, in what is now the Czech Republic but which in 1905 was part of Austro-Hungary. The oldest son of Alfred and Marianne Placzek, George spent his childhood in Brno and in Alexovice, where the family possessed a textile factory, Skene & Co. He had a brother, Friedrich, one year younger and a sister, Edith, twelve years younger. George studied in the Deutsches Staatsgymnasium in Brno between 1918 and 1924 and then went to study physics in the University of Vienna and in Charles University Prague. He graduated with distinction in Vienna in 1928. Placzek often served as an insightful critic, identifying weak arguments and forcing his colleagues to formulate their scientific ideas clearly. These features made him a welcome collaborator and team member. Many renowned physicists became his collaborators and friends, e.g. (besides the above mentioned ones), Werner Heisenberg, Enrico Fermi, Edoardo Amaldi, Edward Teller, Felix Bloch, Victor Weisskopf, George Gamow, John Wheeler, Robert Oppenheimer, Leon Van Hove and others. Placzek belongs to great persons of the physics of the 20th century. He has set an example not only by his discoveries, but also by the stimulating style of his scientific work.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».