arXiv subjects

Yefim S. Levin

Publications and source records attributed to Yefim S. Levin.

5 recordsLinked to original sources

arXiv2026

Relativistic deceleration vs acceleration, Unruh effect observation, and the Schott energy

This article examines finite-time relativistic deceleration and its energy balance within the Lorentz-Abraham-Dirac equation, with special attention to boundary Schott-energy terms. From experimental and kinematical viewpoints, deceleration differs from acceleration. Proper accelerations or decelerations relevant to Unruh-effect observations may be more naturally realized in deceleration than in comparable acceleration scenarios. Deceleration from finite initial energy to rest can occur only over a finite time interval, unlike idealized acceleration, which can continue indefinitely. Thus, finite acceleration or deceleration must include boundary transitions in the radiation-energy balance. We first obtain expressions for the time and distance required for a relativistic particle with nonzero initial velocity to stop under constant deceleration. Applied to the Lynch-Cohen-Hadad-Kaminer (LCHK) estimate, they show that the quoted extremely large deceleration cannot represent sustained classical uniform proper deceleration over a macroscopic crystal length. The stopping time and distance would be too small, and the upper bound on sustained deceleration is far below that estimate. We next consider a charged particle entering and leaving a uniform acceleration or deceleration interval without a velocity jump. This motion can be described within the LAD equation if the external force includes impulses during the short transitions between inertial and uniformly accelerated or decelerated motion. External work is not locally converted directly into radiation during the uniform segment. The Schott energy acts instead as an intermediate reservoir: it changes during the transitions and supplies the radiated energy during the subsequent uniform interval. This idealized LAD radiation mechanism is absent from the Lorentz-equation description and from LAD descriptions that neglect boundary conditions.

physics.class-ph↗

arXiv2024

Some Theoretical Aspects of Observation of Acceleration Induced Thermality

In recent work by M.H.Lynch, E.Cohen, Y.Hadad and I.Kaminer (LCHK), a modified model of the Unruh-DeWitt quantum detector, coupled to a 4-vector current, has been proposed to examine the radiation emitted by high energy positrons channeled into silicon crystal samples. Inspired by their ideas, we analyze theoretical aspects of such a model, its internal consistency, and ignore all questions related to experiments. The two-potential correlation functions for the quantized electromagnetic field in a vacuum state and the corresponding detector radiation power (DRP), considered in proper time formalism, are used as the basis for investigating the radiation observed at an accelerating point detector. The quantum detector is assumed to be moving through an electromagnetic vacuum along a classical hyperbolic trajectory with a constant proper acceleration. The DRP is obtained for three possible cases. First, the DRP is found in a Lorentz-invariant manner. It contains both transverse and non-physical longitudinal polarization modes and is a divergent quantity. Second, the radiation power holds only physical transverse modes but it is non-relativistic and also depends on the detector proper time, which contradicts the fact that there is no preferred time for hyperbolic detector motion. Third, in the case considered by LCHK, for zero detector proper time when its velocity in the lab inertial system is zero, the radiation power with transverse modes shows some signs of thermality which could be associated with a detector acceleration but different from the Bose-Einstein statistics expected for the photon field. If the detector energy gap is zero then, in complete contradiction with what LCHK claim, there is no radiation and no "thermalized Larmor formula". Based on our analysis we do not believe that the LCHK's model can be used to support the idea about thermal effects of uniform acceleration.

gr-qc↗

arXiv2016

Circular Motion of a Small Oscillator in a Zero-Point Field Without External Forces: Is It Possible?

A small dipole oscillator moving along a circular trajectory in zero-point electromagnetic field ( ZPF ) and with a polarization normal to the rotation plane, is considered. Temporal periodicity conditions are imposed on ZPF, associated with the way the rotating oscillator observes ZPF. They are similar to spatial boundary conditions in Casimir phenomenon and therefore result in ZPF spectrum change from continuous one to a discrete one and, as a consequence, an effective temperature of the modified ZPF (Y. S. Levin ). The average centripetal average force on the oscillator, originating from this modified ZPF scattered by the oscillator in the near zone, is calculated in terms of the bilinear correlation functions of electromagnetic field. After renormalization of the correlation function, which physically means extraction of a pure effect of periodicity, the force has a finite value. All calculations are carried out using the methodology of stochastic electrodynamics. The radial component of the force is directed to the center of rotation. In non relativistic case and for oscillator frequency smaller than rotation frequency, the force turns out to be proportional to the rotation radius. Such result could mean a possibility that micro motion of the oscillator in ZPF sustains its average circular motion without any other external forces.Though the estimation done for the point-like electron shows that the effect is not observable because the radius of such circular electron motion would have been much smaller than the classical electron radius when our semi classical approach to the electromagnetic problem does not work. It is well expected result and considered as the first step in the application of the idea in the quark world governed by non abelian colored fields, subject of the next paper.

quant-ph↗

arXiv2007

Thermal Effects of Rotation in Random Classical Zero-Point Radiation

The rotating reference system, two-point correlation functions, and energy density are used as the basis for investigating thermal effects observed by a detector rotating through random classical zero-point radiation. The RS consists of Frenet -Serret orthogonal tetrads where the rotating detector is at rest and has a constant acceleration vector. The CFs and the energy density at the rotating reference system should be periodic with rotation period because CF and energy density measurements is one of the tools the detector can use to justify the periodicity of its motion. The CFs have been calculated for both electromagnetic and massless scalar fields in two cases, with and without taking this periodicity into consideration. It turned out that only periodic CFs have some thermal features and particularly the Planck's factor with the temperature T= h w /k . Regarding to the energy density of both electromagnetic and massless scalar field it is shown that the detector rotating in the zero-point radiation observes not only this original zero-point radiation but, above that, also the radiation which would have been observed by an inertial detector in the thermal bath with the Plank's spectrum at the temperature T. This effect is masked by factor 2/3(4 gamma^2-1) for the electromagnetic field and 2/9 (4 gamma ^2-1) for the massless scalar field, where the Lorentz factor gamma=(1 - v^2 / c^2)^(1/2). Appearance of these masking factors is connected with the fact that rotation is defined by two parameters, angular velocity w and the radius of rotation, in contrast with a uniformly accelerated linear motion which is defined by only one parameter, acceleration a. Our calculations involve classical point of view only and to the best of our knowledge these results have not been reported in quantum theory yet.

math-ph↗

arXiv2006

Rotation in classical zero-point radiation and in quantum vacuum

Two reference systems (RS) are defined and used as the basis for investigating thermal effects of rotation through both random classical zero point radiation and quantum vacuum. Both RSs consist of an infinite number of instantaneous global inertial reference frames (RF). The RFs do not accompany the detector and are defined so that at each moment of proper time of the detector there are two RFs belonging with different RSs. These RFs agree momentarily, are connected by a Lorentz transformation with the detector velocity as a parameter, and with origins at the detector location at the same proper time. The two- field correlation functions (CF) measured by the observer rotating through a random classical zero point radiation have been calculated and presented in terms of elementary functions for both electromagnetic and massless scalar fields. If the CFs are periodic with a period of rotation the observer finds the spectrum which is very similar, but not identical, to Plank spectrum. If both fields of such a two-field periodic CF, for both electromagnetic and massless scalar case, are taken at the same point then its convergent part is shown, using Abel-Plana summation formula, to have Planck spectrum with the temperature T= hw/k, where w is an angular velocity of the detector. It is shown that the vacuum of the quantized massless scalar field in rotating RS is not equivalent to the vacuum of the field in the laboratory system because the respective Bogolubov transformation is not a zero.

math-ph↗