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If the total integral including both 0<V<c and c<V<infinity is considered, divergence will be reduced.Firstly,we use the Cherenkov radiation in media as analogue to confirm the formulation (7)-(10) of a tachyon in vacuum.Then these equations are applied to calculate the Lamb shift and the cut-off frequency is unnecessary.
If the history of science has taught us anything, it's that persistence and creativity makes the once impossible possible. It has long been thought experimental tests of quantum gravity are impossible. But during the last decade, several different approaches have been proposed that allow us to test, if not the fundamental theory of quantum gravity itself, so at least characteristic features this theory can have. For the first time we can probe experimentally domains in which quantum physics and gravity cohabit, in spite of our failure so far to make a convincing marriage of them on a theoretical level.
Method given for intuitively visualizing constancy of light speed. Using mass-energy equivalence, we can show with the help of simple thought experiments, that velocity time dilation and gravitational time dilation are a necessary consequence of principle of relativity. Speed of light is discussed in the context of each kind of time dilation.
This is a comment on a paper by Greaves, Rodriguez, and Ruiz-Camacho [Am. J. Phys. 77, 894 (2009)] which reports a measurement of the one-way speed of light.
The reason for baryon asymmetry in our universe has been a pertinent question for many years. The holographic principle suggests a charged preon model underlies the Standard Model of particle physics and any such charged preon model requires baryon asymmetry. This note estimates the baryon asymmetry predicted by charged preon models in closed inflationary Friedmann universes.
In the present paper it is demonstrated that Bell's expression for local hidden variable correlation allows one to derive the quantum correlation. This raises questions about the use of Bell inequalities in experiments. In the paper a CHSH violating example is given based solely on the locality arguments of the model.
An analysis of Wolfenstein parametrization for the Kobayashi-Maskawa matrix shows that it has a serious flaw: it depends on {\em three} independent parameters instead of {\em four} as it should be. Because this approximation is currently used in phenomenological analyzes from the quark sector, the reliability of almost all phenomenological results is called in question. Such an example is the latest PDG fit from \cite{CA}, p. 150. The parametrization cannot be fixed since even when it is brought to an exact form it has the same flaw and its use lead to many inconsistencies.
Earth is the only known inhabited planet in the universe to date. However, advancements in the fields of astrobiology and observational astronomy, and the discovery of large varieties of extremophiles with extraordinary capablities to thrive the in the harshest environments on Earth, have led to speculation that life may be thriving on many of the extraterrestrial bodies in the universe. Coupled with the growing number of exoplanets detected over the past decade, the search for the possibility of life on other planets and satellites within the solar system and beyond has become a passion as well as a challenge for scientists in a variety of fields. This paper examines such possibility of finding life, in the light of findings of the numerous space probes and theoretical research undertaken in this field over the past few decades.
The possibility of registration of quantum states, such as the coalescence of droplets (tactoids) in the sol phase of aqueous vanadium pentoxide V$_2$O$_5$, with positron annihilation lifetime spectroscopy is discussed. The decrease of the long-living positronium (Ps) lifetime term in the result of the coalescence of V$_2$O$_5$ tactoids is predicted.
There are significant discrepancies between observational evidence and the hierarchical galaxy formation theory with respect to the shape of dark matter halos, the correlation between galaxy characteristics, and galaxy evolutionary history. This paper introduces a modification to the hierarchical galaxy formation theory that hypothesizes that dark matter enters into highly elliptical orbits, and is therefore, effectively redistributed during the period of galactic nuclei activity. Adding this modification, the theory more accurately predicts the observed development history of galaxies and their resulting mature state. In particular, this modification predicts that galaxies grow in size, but not in mass, at an early time (~7 to 10 billion years ago), and develop their characteristic rotation curves which, at large radius, exhibit a relatively flat shape versus the expected Keplerian decline.
With the rotation of charge in a circular path current-loop is generated. This results in the production of magnetic fields in a charged body. This self (internal) magnetic field is treated here with five different radii of electron. Closed loop line integral of magnetic induction vector or the integral form of the Ampere's circuital law is expressed in terms intrinsic properties of electron.
This article addresses broad trends in interdisciplinary research in physics where interactions with colleagues in fields such as computer science, ecology, or economics can often be derailed by unintentional clashes of methodologies and perspectives on the core science. Key causes of such breakdowns in interdisciplinary work are detailed and solutions offered.
Expressing the Wigner distribution function in Dirac notation reveals its resemblance to a classical trajectory in phase space.
The moon is receding from earth at an average rate of 3.8 cm/yr [6][7][9][12].This anomaly cannot be attributed to the well-known tidal exchange of angular momentum between earth and moon [8]. A secular change in the astronomical unit AU is definitely a concern, it is reportedly increasing by about 15 cm/yr [9][10], in this letter; the concept of macroscopic quantization of gravity is introduced to account for these anomalies on theoretical basis. Interestingly, it was found useful in measuring the speed of gravity! What is more interesting is the fact that this concept is based on solid well known classical physics with no modifications to any standard model. It was found that the speed of gravity cg is in the range 10^4 c < cg < 10^5 c.
During the last few decades scientists have been able to test the bases of the physics paradigms, where the quantum mechanics has to match the cosmological scales. Between the extremes of this scenario, biological phenomena and their complexity take place, challenging the laws we observe in the atomic and sub-atomic world. In order to explore the details of this world, new huge experimental facilities are under construction. These projects involve people coming from several countries and give physicists the opportunity to work together with chemists, biologists and other scientists. The Roman Young Researchers Meeting is a conference, organised by Ph. D. students and young postdocs connected to the Roman area. It is aimed primarily at graduate students and post-docs, working in physics. The 1st conference has been held on the 21st of July 2009 at the University of Roma Tor Vergata. It was organised in three sessions, devoted to Astrophysics and Cosmology, Soft and Condensed Matter Physics and Theoretical and Particle Physics. In this proceeding we collect the contributions which have been presented and discussed during the meeting, according to the specific topics treated.
A statistical model is proposed which ascribes the Z^0 mass to the screening properties of the neutrino Fermi sea (neutrino vacuum). Concerning the fermion masses, some puzzling features of the Higgs mechanism are examined. Arguments are advanced, based on the Zitterbevegung theory of the electron substructure, showing that in low energy experiments electron behaves as an extended distribution of charge, though its size comes out less than 10^-16 cm in high energy experiments. This might be a clue for explaining the origin of fermion masses without resorting to Higgs field.
A new type of resonant light absorption by a small particle (nanocluster) is reported. The problem cannot be described within the commonly used dipole scattering approximation and should be studied with methods based upon the exact Mie solution. It is shown that the absorption cross-section has giant maxima realized at small values of the imaginary part of the complex dielectric permittivity of the particle. The maxima are situated in the vicinity of the plasmon (polariton) resonances and correspond to the regions where the dissipative damping equals the radiative one. The case is similar to the recently introduced anomalous scattering [PRL vol. 97, 263902 (2006)] and exhibits similar peculiarities.
The speed of laser light pulses launched from Earth and returned by a retro-reflector on the Moon was calculated from precision round-trip time-of-flight measurements and modeled distances. The measured speed of light (c) in the moving observers rest frame was found to exceed the canonical value c = 299,792,458 m/s by 200+/-10 m/s, just the speed of the observatory along the line-of-sight due to the rotation of the Earth during the measurements. This is a first-order violation of local Lorentz invariance; the speed of light seems to depend on the motion of the observer after all, as in classical wave theory, and implies that a preferred reference frame exists for the propagation of light. However, the present experiment cannot identify the physical system to which such a reference frame might be tied.