Запись семинара им. Зельманова от 10.12.2025

Квантовые измерения в лазерных гравитационных антеннах. Автор(ы): С.П. Вятчанин (Физический факультет МГУ им. М.В. Ломоносова). Аннотация: Laser GW antenna is the unique displacement meter, measuring distance 4 km between 40-kg masses with unique sensitivity about 10^{-19} m. Current sensitivity is close to Standard Quantum Limit (SQL), which is a consequence of Heisenberg uncertainty principle. We discuss the reasons of SQL (measurement noise and back action) and methods to surpass it: quantum non-demolition measuremens (QND), quantum variational measurements, speedmeter and usage of optical rigidity. We also consider the methods of broadband variational measurement for mechanical oscillator, so called ``system free from quantum mechanics'' (SFQM) and ``negative mass''.