Equivalence principle and acceleration effect in optics
Seminars
FLNP Joint Laboratory Seminar
Scientific leader: Egor Lychagin
Date and Time: Thursday, 19 March 2026, at 3:00 PM
Venue: Conference Hall, Frank Laboratory of Neutron Physics, online in Webinar
Seminar topic: “Equivalence principle and acceleration effect in optics”
Speaker: Alexander Frank
Abstract:
Several years ago, it was shown that one of the consequences of the fundamental Equivalence Principle is the so-called Acceleration Effect. According to this effect, any object that scatters a wave or transmits a narrowband signal inevitably changes the wave’s frequency if it is moving with acceleration. The frequency shift is then determined by the relation Δω=kaΔτ, where k is the wave number, a is the acceleration, and Δτ is the time delay introduced by the object when transmitting the signal. The simplest manifestation of the acceleration effect is the case of signal retransmission by a transceiver moving with acceleration. In microphysics, the Acceleration Effect should manifest itself, for example, when a wave passes through a refracting sample moving with acceleration or when a particle is scattered by an accelerating object. So far, the Acceleration Effect has been observed only in neutron optics, and two of the three existing experiments were carried out by the FLNP-ILL group. The report will discuss the possibility of setting up an experiment to demonstrate the Acceleration Effect in optics. The connection of the Acceleration Effect with the equivalence principle means that the proposed experiment will test the validity of the equivalence principle in a new phenomenon.
Several years ago, it was shown that one of the consequences of the fundamental Equivalence Principle is the so-called Acceleration Effect. According to this effect, any object that scatters a wave or transmits a narrowband signal inevitably changes the wave’s frequency if it is moving with acceleration. The frequency shift is then determined by the relation Δω=kaΔτ, where k is the wave number, a is the acceleration, and Δτ is the time delay introduced by the object when transmitting the signal. The simplest manifestation of the acceleration effect is the case of signal retransmission by a transceiver moving with acceleration. In microphysics, the Acceleration Effect should manifest itself, for example, when a wave passes through a refracting sample moving with acceleration or when a particle is scattered by an accelerating object. So far, the Acceleration Effect has been observed only in neutron optics, and two of the three existing experiments were carried out by the FLNP-ILL group. The report will discuss the possibility of setting up an experiment to demonstrate the Acceleration Effect in optics. The connection of the Acceleration Effect with the equivalence principle means that the proposed experiment will test the validity of the equivalence principle in a new phenomenon.