photon frequency
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Author(s):  
Jin Tong Wang ◽  
Jiangdi Fan ◽  
Aaron X. Kan

It has been well known that there is a redshift of photon frequency due to the gravitational potential. Scott et al. [Can. J. Phys. 44 (1966) 1639, https://doi.org/10.1139/p66-137 ] pointed out that general relativity theory predicts the gravitational redshift. However, using the quantum mechanics theory related to the photon Hamiltonian and photon Schrodinger equation, we calculate the redshift due to the gravitational potential. The result is exactly the same as that from the general relativity theory.


2021 ◽  
Author(s):  
Yuan Shi

Abstract In addition to nonzero forces and nontrivial metrics, here I show that a nonconstant Higgs expectation value, which endows elementary particles with their masses, also leads to apparent universal particle accelerations and photon frequency shifts. When effects of the Higgs is attributed to spacetime curvatures, a spurious stress-energy tensor is required in Einstein’s equation. On cosmological scales, the spurious density coincides with the observed dark energy density. On smaller scales, effects of the Standard Model Higgs gradients are unlikely observable except near compact astrophysical bodies. To estimate the experimental precision required to disambiguate causes of apparent accelerations, I compare distinct effects of the force, metric, and Higgs profiles that cause uniform acceleration of a test particle. When the acceleration is caused by a force, the motion of all particles are hyperbolic with the same acceleration. However, when the cause is a metric, only a one-parameter family of particles undergo hyperbolic motion. In comparison, when the cause is a Higgs gradient, the trajectory of all particles are hyperbolic, but the acceleration is larger when the particle’s energy is higher. The discrepancies among the three causes are minuscule on laboratory scales, which makes experimental tests very challenging.


2021 ◽  
Vol 127 (2) ◽  
Author(s):  
Paul Fisher ◽  
Robert Cernansky ◽  
Ben Haylock ◽  
Mirko Lobino

2021 ◽  
Author(s):  
Xinyang Li ◽  
Arkajit Mandal ◽  
Pengfei Huo

Recent experiments have demonstrated remarkable mode-selective reactivities by coupling molecular vibrations with vacuum fluctuations inside an optical cavity. The fundamental mechanism behind such effects, on the other hand, remains elusive. In this work, we theoretically demonstrate the basic principle of how cavity photon frequency can be tuned to achieve mode-selective reactivities. We find that the non-Markovian nature of the radiation mode leads to a cavity frequency-dependent dynamical caging effect of a reaction coordinate, resulting in a suppression of the rate constant. In the presence of multiple competitive reactions, it is possible to preferentially cage a reaction coordinate when the barrier frequencies for competing reaction paths are different. Our theoretical results illustrate the cavity-induced mode-selective chemistry through polaritonic vibrational-strong couplings, revealing the fundamental mechanism for changing chemical selectivities through cavity quantum electrodynamics.


2021 ◽  
Author(s):  
Xinyang Li ◽  
Arkajit Mandal ◽  
Pengfei Huo

Recent experiments have demonstrated remarkable mode-selective reactivities by coupling molecular vibrations with vacuum fluctuations inside an optical cavity. The fundamental mechanism behind such effects, on the other hand, remains elusive. In this work, we theoretically demonstrate the basic principle of how cavity photon frequency can be tuned to achieve mode-selective reactivities. We find that the non-Markovian nature of the radiation mode leads to a cavity frequency-dependent dynamical caging effect of a reaction coordinate, resulting in a suppression of the rate constant. In the presence of multiple competitive reactions, it is possible to preferentially cage a reaction coordinate when the barrier frequencies for competing reaction paths are different. Our theoretical results illustrate the cavity-induced mode-selective chemistry through polaritonic vibrational-strong couplings, revealing the fundamental mechanism for changing chemical selectivities through cavity quantum electrodynamics.


2021 ◽  
Author(s):  
Jing Zhang

Abstract The fast and slow fading of radio signal transmissions or laser beam itself and its spare light confirm the presence of two kinds of collisions --- electron-photon and photon-photon collision. Photon transmissions of radio signals are either in consecutive dense photon groups in slow fading process or widespread group pattern in fast fading form. The photon transmission shapes are irregular and dynamical changes. The radio frequency shift and the wavelength reduction by the calculation demonstrate decelerations of radio/light transmission speeds due to the gradual reduced distance between two consecutive photon groups along the transmission pathway. The simultaneous presence of two radio/light transmission patterns overturns the principle of Special Relativity by Einstein. Photons from radio signals are able to affect electron movements in radio signal receiving process and electrons able to kick photons into space during radio signal emission. The radio signal and light emission and reception are due to the collision between photons and electrons. The local electromagnetic changes between atoms of antenna play the central role. Collision Mechanism explains electron-photon frequency relation of light/radio emission mechanism. Collisions between high- and low-speed photons reduce the speed of high ones. The mathematical equation for the relationship between light/radio transmission speeds before and after photons collisions is established. The equation is confirmed by the calculations of well-known difference of light transmission speeds in different media. The gravities from Earth and Sun play little role during light/radio transmission.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Xinyang Li ◽  
Arkajit Mandal ◽  
Pengfei Huo

AbstractRecent experiments demonstrate the control of chemical reactivities by coupling molecules inside an optical microcavity. In contrast, transition state theory predicts no change of the reaction barrier height during this process. Here, we present a theoretical explanation of the cavity modification of the ground state reactivity in the vibrational strong coupling (VSC) regime in polariton chemistry. Our theoretical results suggest that the VSC kinetics modification is originated from the non-Markovian dynamics of the cavity radiation mode that couples to the molecule, leading to the dynamical caging effect of the reaction coordinate and the suppression of reaction rate constant for a specific range of photon frequency close to the barrier frequency. We use a simple analytical non-Markovian rate theory to describe a single molecular system coupled to a cavity mode. We demonstrate the accuracy of the rate theory by performing direct numerical calculations of the transmission coefficients with the same model of the molecule-cavity hybrid system. Our simulations and analytical theory provide a plausible explanation of the photon frequency dependent modification of the chemical reactivities in the VSC polariton chemistry.


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