5 research outputs found

    Future soft singularities, Born-Infeld-like fields and particles

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    We consider different scenarios of the evolution of the universe, where the singularities or some non-analyticities in the geometry of the spacetime are present, trying to answer the following question: is it possible to conserve some kind of notion of particle corresponding to a chosen quantum field present in the universe when the latter approaches the singularity? We study scalar fields with different types of Lagrangians, writing down the second-order differential equations for the linear perturbations of these fields in the vicinity of a singularity. If both independent solutions are regular, we construct the vacuum state for quantum particles as a Gaussian function of the corresponding variable. If at least one of two independent solutions has a singular asymptotic behavior, then we cannot define the creation and the annihilation operators and construct the vacuum. This means that the very notion of particle loses sense. We show that at the approaching to the Big Rip singularity, particles corresponding to the phantom scalar field driving the evolution of the universe must vanish, while particles of other fields still can be defined. In the case of the model of the universe described by the tachyon field with a special trigonometric potential, where the Big Brake singularity occurs, we see that the (pseudo) tachyon particles do not pass through this singularity. Adding to this model some quantity of dust, we slightly change the characteristics of this singularity and tachyon particles survive. Finally, we consider a model with the scalar field with the cusped potential, where the phantom divide line crossing occurs. Here the particles are well defined in the vicinity of this crossing point.Comment: 13 pages, 1 figure. Final version to be published in PR

    The Unruh effect under the de Broglie-Bohm perspective

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    We investigate the Minkowski ground state associated with a real massless scalar field as seen by an accelerated observer under the perspective of the de Broglie-Bohm quantum theory. We use the Schr\"odinger picture to obtain the wave functional associated with the Minkowski vacuum in Rindler coordinates, and we calculate the field trajectories through the Bohmian guidance equations. The Unruh temperature naturally emerges from the calculus of the average energy, but the Bohmian approach precisely distinguishes between its quantum and classical components, showing that they periodically interchange their roles as the dominant cause for the temperature effects, with abrupt jumps in the infrared regime. We also compute the power spectra, and we exhibit a very special Bohmian field configuration with remarkable physical properties.Comment: 32 pages, 6 figure

    Controlling the Quality of Nanodrugs According to Their New Property—Radiothermal Emission

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    Previous studies have shown that complexly shaped nanoparticles (NPs) have their intrinsic radiothermal emission in the millimeter range. This article presents a method for controlling the quality of nanodrugs—immunobiological preparations (IBPs)—based on the detection of their intrinsic radiothermal emissions. The emissivity of interferon (IFN) medicals, determined without opening the primary package, is as follows (µW/m2): IFN-α2b—80 ± 9 (105 IU per package), IFN-β1a—40 ± 5 (24 × 106 IU per package), IFN-γ—30 ± 4 (105 IU per package). The emissivity of virus-like particles (VLP), determined using vaccines Gam-VLP-multivac (120 μg) in an injection bottle (crimp cap vials), was as follows: 12 ± 1 µW/m2, Gam-VLP—rota vaccines—9 ± 1 µW/m2. This study shows the reproducibility of emissivity over the course of a year, subject to the storage conditions of the immunobiological products. It has been shown that accelerated aging and a longer shelf life are accompanied by the coagulation of active NPs, and lead to a manyfold drop in emissivity. The dependence of radiothermal emission on temperature has a complex, non-monotonic nature. The emission intensity depends on the form of dosage, but remains within the order of magnitude for IFN-α2b for intranasal aqueous solution, ointments, and suppositories. The possibility of the remote quantitative control of the first phases of the immune response (increased synthesis of IFNs) to the intranasal administration of VLP vaccines has been demonstrated in experimental animals
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