On résout un problème extrêmal concernant des fonctions caractéristiques soumises à la condition de s'annuler en un point fixé. L'origine du problème est l'étude de l'amplitude de survie d'un état quantique dans la dynamique de Schrödinger, et la solution exprime un phénomène curieux dans l'évolution des systèmes quantiques.
We study an extremal problem concerning the supremum of the Fourier transforms (characteristic functions) of probability distributions under the constraint that the Fourier transforms vanish at a fixed point. This problem arises from the investigation of the survival amplitudes of quantum states driven by Schrödinger dynamics, and has general and curious implications for the evolution pictures of quantum systems.
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@article{CRMATH_2005__341_5_293_0, author = {Luo, Shunlong and Zhang, Zhengmin}, title = {An extremal problem for {Fourier} transforms of probabilities}, journal = {Comptes Rendus. Math\'ematique}, pages = {293--296}, publisher = {Elsevier}, volume = {341}, number = {5}, year = {2005}, doi = {10.1016/j.crma.2005.07.021}, language = {en}, url = {http://www.numdam.org/articles/10.1016/j.crma.2005.07.021/} }
TY - JOUR AU - Luo, Shunlong AU - Zhang, Zhengmin TI - An extremal problem for Fourier transforms of probabilities JO - Comptes Rendus. Mathématique PY - 2005 SP - 293 EP - 296 VL - 341 IS - 5 PB - Elsevier UR - http://www.numdam.org/articles/10.1016/j.crma.2005.07.021/ DO - 10.1016/j.crma.2005.07.021 LA - en ID - CRMATH_2005__341_5_293_0 ER -
%0 Journal Article %A Luo, Shunlong %A Zhang, Zhengmin %T An extremal problem for Fourier transforms of probabilities %J Comptes Rendus. Mathématique %D 2005 %P 293-296 %V 341 %N 5 %I Elsevier %U http://www.numdam.org/articles/10.1016/j.crma.2005.07.021/ %R 10.1016/j.crma.2005.07.021 %G en %F CRMATH_2005__341_5_293_0
Luo, Shunlong; Zhang, Zhengmin. An extremal problem for Fourier transforms of probabilities. Comptes Rendus. Mathématique, Tome 341 (2005) no. 5, pp. 293-296. doi : 10.1016/j.crma.2005.07.021. http://www.numdam.org/articles/10.1016/j.crma.2005.07.021/
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