Gravitation and inertia; a rearrangement of vacuum in gravity

We address the gravitation and inertia in the framework of 'general gauge principle', which accounts for 'gravitation gauge group' generated by hidden local internal symmetry implemented on the flat space. We connect this group to nonlinear realization of the Lie group of 'distortion' of local internal properties of six-dimensional flat space, which is assumed as a toy model underlying four-dimensional Minkowski space. The agreement between proposed gravitational theory and available observational verifications is satisfactory. We construct relativistic field theory of inertia and derive the relativistic law of inertia. This theory furnishes justification for introduction of the Principle of Equivalence. We address the rearrangement of vacuum state in gravity resulting from these ideas.Comment: 17 pages, no figures, revtex4, Accepted for publication in Astrophys. Space Sc

BGWM as Second Constituent of Complex Matrix Model

Earlier we explained that partition functions of various matrix models can be constructed from that of the cubic Kontsevich model, which, therefore, becomes a basic elementary building block in "M-theory" of matrix models. However, the less topical complex matrix model appeared to be an exception: its decomposition involved not only the Kontsevich tau-function but also another constituent, which we now identify as the Brezin-Gross-Witten (BGW) partition function. The BGW tau-function can be represented either as a generating function of all unitary-matrix integrals or as a Kontsevich-Penner model with potential 1/X (instead of X^3 in the cubic Kontsevich model).Comment: 42 page

Disordered Nonlinear Metalens for Raman Spectral Nanoimaging

© 2020 American Chemical Society. Over the past decades, considerable progress has been made toward far-field optical imaging beyond the diffraction limit. However, most working proof-of-concepts are based on either time-consuming scanning of a subdiffraction focal spot over a sample or postrecovery treatment using a priori information on a sought image. To our knowledge, none of these can be regarded as being close to a perfect far-field superlensing system capable of real-time color imaging with subwavelength resolution. In this paper, we suggest a proof-of-concept for far-field nonlinear metalens that is made of a disordered metal-dielectric nanocomposite. Postoxidation of a refractory titanium nitride (TiN) thin film, used as a nonlinear plasmonic material, results in the formation of a titanium oxynitride (TiON) film comprising a mixture of multiple phases of TiOxNy. Due to a double epsilon-near-zero behavior near the percolation threshold, the TiON favors supercoupling of the incident light to surface plasmon resonance within the visible and near-infrared range. Point spread function narrowing is achieved owing to the multiplicative nature of stimulated Raman scattering (SRS) and enhanced third-order optical nonlinearity in TiN and TiO2 particle chains through plasmon resonances and Anderson localization of light, respectively. Combined with a conventional confocal optical microscope, the multimode metalens shows subwavelength resolution of λ/6NA at different visible wavelengths (SRS overtones) using multiwalled carbon nanotubes as a test sample. We are confident that our finding will bring us one step closer to developing a robust and versatile far-field super-resolution color imaging system and, eventually, implementing "eye-on-a-chip" technology

Nanoscale Sensing Vitrification of 3D Confined Glassy Polymers through Refractory Thermoplasmonics

Advances in plasmonics have been fundamentally rooted in minimizing ohmic losses in metallic nanostructures. However, the losses at resonance can play a positive role; for instance, in optical heating, there are two sides to every story. Under laser illumination, plasmonic nanostructures serve not only as near-field enhancers but heat generators. The emerging field of thermoplasmonics opens up unprecedented possibilities to probe temperature-dependent phase transitions locally. In this paper, we develop a new approach behind plasmon-assisted optical heating for spectroscopically recognizing the glass transition temperature (Tg) of spatially confined poly(methyl methacrylate) (PMMA) polymers deposited on a square-shaped titanium nitride (TiN) pad. A local photoheating is controlled through Raman thermometry of a c-Si (100) substrate that functions as a temperature-sensing Raman reporter. The reliability of temperature measurements is corroborated by using both the anti-Stokes/Stokes ratio and the Raman peak shift. We show that optical heating can be adjusted by extruding a c-Si substrate, for example, the temperature increase is achieved by making c-Si pillars beneath the TiN pads longer. This peculiarity gives the possibility to probe the Tg in a broad temperature range for the diversity of glassy polymers. We believe that the developed method will pave the way for 2D mapping structural glass transitions of heterogeneous glassy polymers, polymeric blends, and eventually, 3D confined polymers

MEASUREMENT OF CO2 SORPTION AND PEG 1500 SWELLING BY ATR-IR SPECTROSCOPY

In situ high-pressure ATR-IR spectroscopy was applied to simultaneously measure the sorption of CO2 in polyethylene glycol (PEG) with molecular weight 1500 and the polymer swelling. The band at ca. 2338 cm−1 corresponding to the antisymmetric stretching mode of CO2 was used to calculate concentration of CO2 dissolved in PEG while spectral bands of PEG at ca. 1100 cm−1 were used to calculate swelling of PEG as a function of temperature and pressure. This in situ approach allowed to observe CO2-induced melting of PEG and to assess intermolecular interactions between CO2 and polymer. The solubility of CO2 in PEG 1500 was influenced by both pressure and temperature. It remarkably increased with pressure until the CO2 critical value, then it approached a plateau. Higher solubility was observed at the lower temperature

Analyses of trace amounts of dyes with a new enhanced sensitivity FTIR spectroscopic technique: MU-ATR (metal underlayer ATR spectroscopy)

The identification of organic dyes is a challenging task in all the fields such as the forensic and conservation sciences, especially in cases where the amount of sample is extremely small. In this paper we propose a new enhanced FTIR method (MU-ATR metal underlayer ATR spectroscopy), which we believe is the first of its kind, for the analysis of a few ng of dyes. With this method, dyed fiber micro-extracts can be analyzed using a commercial FTIR microscope with a fixed incident angle, obtaining the same separation between the different classes of dyes investigated as we obtained analyzing pure dyes in transmission mode. Moreover, the new enhancement method has been validated on a real sample dated back to the 1893, showing how it can be promising for the analysis of trace amounts of organic substances in artistic samples such as dyes in paintings or textiles, varnishes and organic residues on archaeological objects

Spectroscopic analysis of triflusal impregnated into PMMA from supercritical CO2 solution

International audienc

ATR-FTIR spectroscopy and spectroscopic imaging of solvent and permeant diffusion across model membranes

The uptake and diffusion of solvents across polymer membranes is important in controlled drug delivery, effects on drug uptake into, for example, infusion bags and containers, as well as transport across protective clothing. Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy has been used to monitor the effects of different solvents on the diffusion of a model compound, 4-cyanophenol (CNP) across silicone membrane and on the equilibrium concentration of CNP obtained in the membrane following diffusion. ATR-FTIR spectroscopic imaging of membrane diffusion was used to gain an understanding of when the boundary conditions applied to Fick's second law, used to model the diffusion of permeants across the silicone membrane do not hold. The imaging experiments indicated that when the solvent was not taken up appreciably into the membrane, the presence of discrete solvent pools between the ATR crystal and the silicone membrane can affect the diffusion profile of the permeant. This effect is more significant if the permeant has a high solubility in the solvent. In contrast, solvents that are taken up into the membrane to a greater extent, or those where the solubility of the permeant in the vehicle is relatively low, were found to show a good fit to the diffusion model. As such these systems allow the ATR-FTIR spectroscopic approach to give mechanistic insight into how the particular solvents enhance permeation. The solubility of CNP in the solvent and the uptake of the solvent into the membrane were found to be important influences on the equilibrium concentration of the permeant obtained in the membrane following diffusion. In general, solvents which were taken up to a significant extent into the membrane and which caused the membrane to swell increased the diffusion coefficient of the permeant in the membrane though other factors such as solvent viscosity may also be important