Falsifying ΛCDM: Model-independent tests of the concordance model with eBOSS DR14Q and Pantheon
We combine model-independent reconstructions of the expansion history from the latest Pantheon supernovae distance modulus compilation and measurements from baryon acoustic oscillation to test some important aspects of the concordance model of cosmology namely the Friedmann-Lemaître-Robertson-Walker (FLRW) metric and flatness of spatial curvature. We then use the reconstructed expansion histories to fit growth measurement from redshift-space distortion and obtain constraints on (Ωm, γ, σ8) in a model independent manner. Our results show consistency with a spatially flat FLRW Universe with general relativity to govern the perturbation in the structure formation and the cosmological constant as dark energy. However, we can also see some hints of tension among different observations within the context of the concordance model related to high redshift observations (z>1) of the expansion history. This supports earlier findings of [G.-B. Zhao, Nat. Astron. 1, 627 (2017), V. Sahni, A. Shafieloo, and A. A. Starobinsky, Astrophys. J. 793, L40 (2014)] and highlights the importance of precise measurement of expansion history and growth of structure at high redshifts.
The article analyzes the writing of Alexander Koiré «From the closed world to the infinite universe» in relation to several achievements of modern physics connected to fundamental concept of space. The evolution of other certain scientific concepts, such as in particular, the «vacuum» and «gravity», also comes under review. The author reaches the key point that the some modern physical theories are again based on the idea of the closed universe.
The monograph "Philosophy of Physics: towards New Principles of New Knowledge" is intended both for those who are just discovering the world of philosophy of science in the most fundamental field – physics, and for specialists who are professionally engaged in the topic and are interested in the most relevant research. The author analyzes a number of key problems of modern physics and cosmology, offers original interpretations and solutions, and also discusses the prospects for the development of science in the context of attempts to create a "Theory of Everything". The book focuses on the physical theories of the multiverse, the new principles of scientific knowledge derived from these theories, and the connection between consciousness and concrete physical reality.
My goal is to conceive how the reality would look like for hypothetical creatures that supposedly perceive on time scales much faster or much slower that of us humans. To attain the goal, I propose modelling in two steps. At step we have to single out a uni“ed parameter that sets time scale of perception. Changing substantially the value of the parameter would mean changing scale. argue that the required parameter is duration of discrete perceptive frames, snapshots, whose sequencing constitutes perceptive process. I show that different standard durations of perceptive frames is the ground for differences in perceptive time scales of various animals. Abnormally changed duration of perceptive frames is the cause of the effect of distorted subjective time observed by humans under some conditions. Now comes step two of the modelling. By inserting some arbitrary duration of a perceptive frame, we set a hypothetical scale and thus emulate viewpoint for virtual observation of the reality in a wider or narrower angle embracing events in time. Like changing lenses of a microscope, viewing reality different temporal scales makes certain features of reality manifested, others veiled. These are, in particular, features of life. If we observe an object in an inappropriate interval, we may not notice the very essence of a process it is undergoing.
En révélant l’influence de l’interprétation de Koyré dans les lectures que fait Henry de la philosophie boehmienne, je propose d’interroger la position henryenne qui, en s’appuyant sur les concepts classiques de l’originaire et de l’authentique, refuse au monde – et par là à toute connaissance théorique – le statut de vérité. Je me demande donc s’il est suffisant d’exclure chaque tentative d’expression de la manifestation de l’Absolu. Peut-être faut-il relire le projet de la phénoménologie comme une science descriptive plutôt que prescriptive ?
I develop the idea that there exists a special dimension of depth, or of scale. The depth dimension is physically real and extends from the bottom micro-level to the ultimate macro-level of the Universe. The depth dimension, or the scales axis, complements the standard three spatial dimensions. I discuss the tentative qualities of the depth dimension and the universal arrangement of matter along this dimension. I suggest that all matter in the Universe, at least in the present cosmological epoch, is in joint downward motion along the depth dimension. The joint downward motion manifests itself in the universal contraction of matter. The opposite direction of motion, upward the dimension, would cause the expansion of matter. The contraction of matter is a primary factor, whereas the shrinking of space in the vicinity of matter is a derivative phenomenon. The observed expansion of the Universe is explained by the fact that celestial bodies become smaller due to matter contraction, while the overall space remains predominantly intact. Thus, relative to the contracting material bodies, the total span of cosmic space appears to be becoming vaster. I attempt to explain how the contraction of matter engenders the effect of universal gravity. I use over thirty animated and graphical color visualizations in the text to make the explanation of the proposed ideas more lucid.
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
Radiation conditions are described for various space regions, radiation-induced effects in spacecraft materials and equipment components are considered and information on theoretical, computational, and experimental methods for studying radiation effects are presented. The peculiarities of radiation effects on nanostructures and some problems related to modeling and radiation testing of such structures are considered.