XXXVIII International Workshop on High Energy Physics and Field Theory “Current issues in gravitation and cosmology”

Quantum Measurements in Gravitational Wave Antennas

26 нояб. 2026 г., 09:45

45m

Morning session 5

Speaker

Sergey Vyatchanin (Lomonosov Moscow State Universuty)

Описание

Abstract
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 quanum mechanics'' (SFQM) andnegative mass''.