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Topic Review
SU(2)/SU(3) Quantum Yang-Mills theory Thermodynamics
An outline of the main, purely theoretical ideas involved in Quantum Yang-Mills thermodynamics is given and implications thereof for applications in cosmology, particle, plasma, and condensed-matter physics are sketched. On the theoretical side, we elucidate the concepts of the thermal ground states of the deconfining and preconfining phases together with their gauge-mode excitations , and we discuss the quantum vacuum of the confining phase including its finite-extent excitations. On the application side, we briefly mention how deconfining SU(2) Yang-Mills thermodynamics, when postulated to describe thermal photon gases, predicts a modified temperature (T) -redshift (z) relation for the Cosmic Microwave Background (CMB) which, in turn, implies a rearrangement of the dark sector well before the onset of nonlinear structure formation. All-z fits of the ensuing cosmological model to the observed angular power spectra  (CMB) yield a value for the present Hubble parameter H0 agreeing with that extracted from local distance measurements, a baryon density of the present Universe being about 30% smaller than the standard value obtained from Big-Bang-Nucleosynthesis (BBN) but matching direct censuses, and a late onset of reionisation of the Universe agreeing with the observation of the Gunn-Peterson trough in high-z quasar spectra. We also mention how the three lepton families of the Standard Model of Particle Physics (SMPP) could emerge as solitons immersed into the confining  phases of three SU(2) Yang-Mills theories, subject to mixing of their Cartan subalgebras. In particular, the electron and its neutrino would be represented by 1-fold selfintersecting and single, stable center-vortex loops with a wealth of implications for strongly correlated charge carriers in the two spatial dimensions of  certain condensed-matter systems as well as ultra hot plasmas.
  • 1.7K
  • 30 Oct 2020
Topic Review
Crystallization of LiNbO3
Due to its piezoelectric, ferroelectric, nonlinear optics, and pyroelectric properties, LiNbO3 crystal has found its wide applications in surface acoustic wave (SAW) devices, optical waveguides, optical modulators, and second-harmonic generators (SHG). LiNbO3 crystallized as R3c space group below Curie temperature shows spontaneous polarization that leads to its ferroelectric and piezoelectric properties. Physical and chemical characteristics of LiNbO3 are mainly determined by Li/Nb ratio, impurity cations, vacancies in a cation sublattice. Different sizes of LiNbO3 ranging from nanoscale and microscale to bulk size have been synthesized by solid state method, hydrothermal/solvothermal method, Czochralski (Cz) growth method, etc. Most basic and applied studies of LiNbO3 focus on its bulk single crystal.
  • 1.7K
  • 17 Dec 2021
Biography
Ashoke Sen
Ashoke Sen, FRS (/əˈʃoʊk sɛn/; born 1956) is an Indian theoretical physicist and distinguished professor at the Harish-Chandra Research Institute, Allahabad.[1] He is also an honorary fellow in National Institute of Science Education and Research (NISER), Bhubaneswar, India [2] and also a Morningstar Visiting professor at MIT and a distinguished professor at the Korea Institute for Advanced
  • 1.7K
  • 16 Nov 2022
Topic Review
Rooftop Photovoltaic Power Station
A rooftop photovoltaic power station, or rooftop PV system, is a photovoltaic (PV) system that has its electricity-generating solar panels mounted on the rooftop of a residential or commercial building or structure. The various components of such a system include photovoltaic modules, mounting systems, cables, solar inverters and other electrical accessories. Rooftop mounted systems are small compared to ground-mounted photovoltaic power stations with capacities in the megawatt range, hence being a form of distributed generation. Most rooftop PV stations in developed countries are Grid-connected photovoltaic power systems. Rooftop PV systems on residential buildings typically feature a capacity of about 5 to 20 kilowatts (kW), while those mounted on commercial buildings often reach 100 kilowatts to 1 Megawatt (MW). Very large roofs can house industrial scale PV systems in the range of 1-10 Megawatts.
  • 1.7K
  • 17 Nov 2022
Topic Review
Different Anisotropic-Strata Interface and Refraction
The strata model inside the earth is close to physical reality. The strata layers can be macro-anisotropic but transversely isotropic, where some are vertically symmetric and the others are not. The macroscopic anisotropy is significant for seismic waves with long wave-length regarding propagation, reflection, refraction, and polarization. This topic review provides the most recent theoretical development related to geophysical applications. 
  • 1.7K
  • 03 Nov 2020
Topic Review
Sound Transmission Losses in DPS
Double panel structures (DPS) are flat or curved structural designs which consist of two opposite facesheets or panels separated by a core or cavity. The cavity may be any kind of enclosed gasses while the core may be any form of solid materials which can be architecturally designed. DPS have been used in various applications for sound insulation purpose.  First, sound incident on the incident facesheet of the DPS, transmitted through the core or cavity and then radiates from the radiating facesheet of the DPS. The ratio of the sound power incident on the incident facesheet to the sound power transmitted through the radiating facesheet is referred as the sound transmission loss of the DPS. The motivation behind the wide industrial application of DPS is owing to their potential characteristics to absorb sound more effectively. Therefore, it is of utmost importance to understand the different geometry and material constituents of the facesheets as well as core/cavity of the DPS. The knowledge of this will help designers and manufacturers to produce the most effective and optimal design of DPS capable of producing very high and desirable sound transmission losses.
  • 1.7K
  • 19 Aug 2020
Topic Review
FTIR for Vehicle Exhaust Emissions
In a Fourier Transform InfraRed (FTIR) spectrometer, some of the infrared (IR) radiation is absorbed by the sample, and some of it is passed through (transmitted). The resulting molecular absorption and transmission response can be used to identify the components of the sample and their concentration.
  • 1.7K
  • 20 Aug 2021
Topic Review
Loopholes in Bell Tests
In Bell tests, there may be problems of experimental design or set-up that affect the validity of the experimental findings. These problems are often referred to as "loopholes". See the article on Bell's theorem for the theoretical background to these experimental efforts (see also John Stewart Bell). The purpose of the experiment is to test whether nature is best described using a local hidden-variable theory or by the quantum entanglement theory of quantum mechanics. The "detection efficiency", or "fair sampling" problem is the most prevalent loophole in optical experiments. Another loophole that has more often been addressed is that of communication, i.e. locality. There is also the "disjoint measurement" loophole which entails multiple samples used to obtain correlations as compared to "joint measurement" where a single sample is used to obtain all correlations used in an inequality. To date, no test has simultaneously closed all loopholes. Ronald Hanson of the Delft University of Technology claims the first Bell experiment that closes both the detection and the communication loopholes. (This was not an optical experiment in the sense discussed below; the entangled degrees of freedom were electron spins rather than photon polarization.) Nevertheless, correlations of classical optical fields also violate Bell's inequality. In some experiments there may be additional defects that make "local realist" explanations of Bell test violations possible; these are briefly described below. Many modern experiments are directed at detecting quantum entanglement rather than ruling out local hidden-variable theories, and these tasks are different since the former accepts quantum mechanics at the outset (no entanglement without quantum mechanics). This is regularly done using Bell's theorem, but in this situation the theorem is used as an entanglement witness, a dividing line between entangled quantum states and separable quantum states, and is as such not as sensitive to the problems described here. In October 2015, scientists from the Kavli Institute of Nanoscience reported that the quantum nonlocality phenomenon is supported at the 96% confidence level based on a "loophole-free Bell test" study. These results were confirmed by two studies with statistical significance over 5 standard deviations which were published in December 2015. However, Alain Aspect writes that No experiment can be said to be totally loophole-free.
  • 1.7K
  • 31 Oct 2022
Topic Review
Power Generation Using Dielectric Elastomers
Power generation using dielectric elastomer (DE) artificial muscle is attracting attention because of its light weight, low cost, and high-efficiency. Since this method is a system that produces electricity without emitting carbon dioxide nor using rare earths, it would contribute to the goal of environmental sustainability. 
  • 1.7K
  • 30 Jun 2021
Topic Review
Acoustical Goos-Hänchen Effect
Goos–Hänchen effect was an important optical phenomenon. When an optical wave propagates from a denser medium to a thinner medium, the total reflection generates coherent interference. The final propagated wave yields a lateral displacement relative to the incidence wave at the interface. Even though optics has a coherent effect on the total reflection of a finite-sized wave and an acoustic wave is incoherent with a non-total reflection of different frequency components, recent research shows that there is an analog Goos–Hänchen effect in acoustics. 
  • 1.6K
  • 14 Apr 2021
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