Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userComment on recent Physical Review Letter by Gaidarzhy, et al. Evidence for quantized displacement in macroscopic nanomechanical oscillator.
228
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
In a recent letter, Gaidarzhy et al. claim to have observed evidence for quantized displacements of a nanomechanical oscillator. We contend that the evidence, analysis, claims, and conclusions presented are contrary to expectations from fundamentals of quantum mechanics and elasticity theory, and that the method used by the authors is unsuitable in principle to observe the quantized energy states of a nanomechanical structure.
rate research
Read More
This is a comment on the paper : Quantum Interference between Light Sources Separated by 150 Million Kilometers by Deng et al, PHYSICAL REVIEW LETTERS 123, 080401 (2019)
The CLAS Collaboration provides a comment on the physics interpretation of the results presented in a paper published by M. Amaryan et al. regarding the possible observation of a narrow structure in the mass spectrum of a photoproduction experiment.
In a recent paper entitled Winding around non-Hermitian singularities by Zhong et al., published in Nat. Commun. 9, 4808 (2018), a formalism is proposed for calculating the permutations of eigenstates that arise upon encircling (multiple) exceptional points (EPs) in the complex parameter plane of an analytic non-Hermitian Hamiltonian. The authors suggest that upon encircling EPs one should track the eigenvalue branch cuts that are traversed, and multiply the associated permutation matrices accordingly. In this comment we point out a serious shortcoming of this approach, illustrated by an explicit example that yields the wrong result for a specific loop. A more general method that has been published earlier by us and that does not suffer from this problem, is based on using fundamental loops. We briefly explain the method and list its various advantages. In addition, we argue that this method can be verified in a three wave-guide system, which then also unambiguously establishes the noncommutativity associated with encircling multiple EPs.
In this comment, we agree with the formulas derived in Refs. [1,2] but show that the results are not due to interference between spatially separated states of the center of mass of a mesoscopic harmonic oscillator.
Unfortunately, Liu et al. contains a number of errors and omissions which compromise its conclusions. These have to do with the amount of 14C which is necessary to deposit in the atmosphere in order to see a perturbation like that in 774 AD, and the ability of a comet to do so.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
