scholarly journals Dynamics in varying vacuum Finsler–Randers cosmology

Author(s):  
G. Papagiannopoulos ◽  
S. Basilakos ◽  
A. Paliathanasis ◽  
Supriya Pan ◽  
P. Stavrinos

AbstractIn the context of Finsler–Randers theory we consider, for the first time, the cosmological scenario of the varying vacuum. In particular, we assume the existence of a cosmological fluid source described by an ideal fluid and the varying vacuum terms. We determine the cosmological history of this model by performing a detailed study on the dynamics of the field equations. We determine the limit of General Relativity, while we find new eras in the cosmological history provided by the geometrodynamical terms provided by the Finsler–Randers theory.

2015 ◽  
Vol 24 (14) ◽  
pp. 1530030
Author(s):  
Martin Bucher ◽  
Wei-Tou Ni

This year marks the 100th anniversary of Einstein’s 1915 landmark paper “Die Feldgleichungen der Gravitation” in which the field equations of general relativity were correctly formulated for the first time, thus rendering general relativity a complete theory. Over the subsequent hundred years, physicists and astronomers have struggled with uncovering the consequences and applications of these equations. This paper, which was written as an introduction to six chapters dealing with the connection between general relativity and cosmology that will appear in the two-volume book One Hundred Years of General Relativity: From Genesis and Empirical Foundations to Gravitational Waves, Cosmology and Quantum Gravity, endeavors to provide a historical overview of the connection between general relativity and cosmology, two areas whose development has been closely intertwined.


2012 ◽  
Vol 2012 ◽  
pp. 1-4
Author(s):  
L. L. Williams

The unification of classical electrodynamics and general relativity within the context of five-dimensional general relativity (Kaluza, 1921, and Thiry, 1948) contains a scalar field which may be identified with the gravitational constant, G. The field equations of this theory are solved under conditions of the Robertson-Walker metric for flat space, for a radiation-dominated universe—a model appropriate for the early history of our universe. This leads to a cosmology wherein G is inversely proportional to the Robertson-Walker scale factor. This result is discussed in the context of the Dirac large number hypothesis and in the context of an expression for G in terms of atomic constants.


1949 ◽  
Vol 1 (3) ◽  
pp. 209-241 ◽  
Author(s):  
A. Einstein ◽  
L. Infeld

The gravitational field manifests itself in the motion of bodies. Therefore the problem of determining the motion of such bodies from the field equations alone is of fundamental importance. This problem was solved for the first time some ten years ago and the equations of motion for two particles were then deduced [1]. A more general and simplified version of this problem was given shortly thereafter [2].Mr. Lewison pointed out to us, that from our approximation procedure, it does not follow that the field equations can be solved up to an arbitrarily high approximation. This is indeed true.


2020 ◽  
Vol 80 (12) ◽  
Author(s):  
A. Triantafyllopoulos ◽  
S. Basilakos ◽  
E. Kapsabelis ◽  
P. C. Stavrinos

AbstractIn this work, we extend for the first time the spherically symmetric Schwarzschild and Schwarzschild–De Sitter solutions with a Finsler–Randers-type perturbation which is generated by a covector $$A_\gamma $$ A γ . This gives a locally anisotropic character to the metric and induces a deviation from the Riemannian models of gravity. A natural framework for this study is the Lorentz tangent bundle of a spacetime manifold. We apply the generalized field equations to the perturbed metric and derive the dynamics for the covector $$A_\gamma $$ A γ . Finally, we find the timelike, spacelike and null paths on the Schwarzschild–Randers spacetime, we solve the timelike ones numerically and we compare them with the classic geodesics of general relativity. The obtained solutions are new and they enrich the corresponding literature.


2013 ◽  
Vol 40 (2) ◽  
pp. 244-256 ◽  
Author(s):  
Holger Funk

In the history of botany, Adam Zalužanský (d. 1613), a Bohemian physician, apothecary, botanist and professor at the University of Prague, is a little-known personality. Linnaeus's first biographers, for example, only knew Zalužanský from hearsay and suspected he was a native of Poland. This ignorance still pervades botanical history. Zalužanský is mentioned only peripherally or not at all. As late as the nineteenth century, a researcher would be unaware that Zalužanský’s main work Methodi herbariae libri tres actually existed in two editions from two different publishers (1592, Prague; 1604, Frankfurt). This paper introduces the life and work of Zalužanský. Special attention is paid to the chapter “De sexu plantarum” of Zalužanský’s Methodus, in which, more than one hundred years before the well-known De sexu plantarum epistola of R. J. Camerarius, the sexuality of plants is suggested. Additionally, for the first time, an English translation of Zalužanský’s chapter on plant sexuality is provided.


2008 ◽  
Vol 1 (2) ◽  
pp. 139-155 ◽  
Author(s):  
YAEL DARR

This article describes a crucial and fundamental stage in the transformation of Hebrew children's literature, during the late 1930s and 1940s, from a single channel of expression to a multi-layered polyphony of models and voices. It claims that for the first time in the history of Hebrew children's literature there took place a doctrinal confrontation between two groups of taste-makers. The article outlines the pedagogical and ideological designs of traditionalist Zionist educators, and suggests how these were challenged by a group of prominent writers of adult poetry, members of the Modernist movement. These writers, it is argued, advocated autonomous literary creation, and insisted on a high level of literary quality. Their intervention not only dramatically changed the repertoire of Hebrew children's literature, but also the rules of literary discourse. The article suggests that, through the Modernists’ polemical efforts, Hebrew children's literature was able to free itself from its position as an apparatus controlled by the political-educational system and to become a dynamic and multi-layered field.


2020 ◽  
Vol 72 (2) ◽  
Author(s):  
Tomasz Dzieńkowski ◽  
Marcin Wołoszyn ◽  
Iwona Florkiewicz ◽  
Radosław Dobrowolski ◽  
Jan Rodzik ◽  
...  

The article discusses the results of the latest interdisciplinary research of Czermno stronghold and its immediate surroundings. The site is mentioned in chroniclers’ entries referring to the stronghold Cherven’ (Tale of Bygone Years, first mention under the year 981) and the so-called Cherven’ Towns. Given the scarcity of written records regarding the history of today’s Eastern Poland, Ukraine, and Belarus in the 10th and 11th centuries, recent archaeological research, supported by geoenvironmental analyses and absolute dating, brought a significant qualitative change. In 2014 and 2015, the remains of the oldest rampart of the stronghold were uncovered for the first time. A series of radiocarbon datings allows us to refer the erection of the stronghold to the second half/late 10th century. The results of several years’ interdisciplinary research (2012-2020) introduce qualitatively new data to the issue of the Cherven’ Towns, which both change current considerations and confirm the extraordinary research potential in the archeology of the discussed region.


Author(s):  
Michael D. Gordin

Dmitrii Mendeleev (1834–1907) is a name we recognize, but perhaps only as the creator of the periodic table of elements. Generally, little else has been known about him. This book is an authoritative biography of Mendeleev that draws a multifaceted portrait of his life for the first time. As the book reveals, Mendeleev was not only a luminary in the history of science, he was also an astonishingly wide-ranging political and cultural figure. From his attack on Spiritualism to his failed voyage to the Arctic and his near-mythical hot-air balloon trip, this is the story of an extraordinary maverick. The ideals that shaped his work outside science also led Mendeleev to order the elements and, eventually, to engineer one of the most fascinating scientific developments of the nineteenth century. This book is a classic work that tells the story of one of the world's most important minds.


Author(s):  
Rachel Ablow

The nineteenth century introduced developments in science and medicine that made the eradication of pain conceivable for the first time. This new understanding of pain brought with it a complex set of moral and philosophical dilemmas. If pain serves no obvious purpose, how do we reconcile its existence with a well-ordered universe? Examining how writers of the day engaged with such questions, this book offers a compelling new literary and philosophical history of modern pain. The book provides close readings of novelists Charlotte Brontë and Thomas Hardy and political and natural philosophers John Stuart Mill, Harriet Martineau, and Charles Darwin, as well as a variety of medical, scientific, and popular writers of the Victorian age. The book explores how discussions of pain served as investigations into the status of persons and the nature and parameters of social life. No longer conceivable as divine trial or punishment, pain in the nineteenth century came to seem instead like a historical accident suggesting little or nothing about the individual who suffers. A landmark study of Victorian literature and the history of pain, the book shows how these writers came to see pain as a social as well as a personal problem. Rather than simply self-evident to the sufferer and unknowable to anyone else, pain was also understood to be produced between persons—and even, perhaps, by the fictions they read.


2020 ◽  
Vol 4 (1) ◽  
pp. 67-86
Author(s):  
Elisabeth Heyne

AbstractAlthough visual culture of the 21th century increasingly focuses on representation of death and dying, contemporary discourses still lack a language of death adequate to the event shown by pictures and visual images from an outside point of view. Following this observation, this article suggests a re-reading of 20th century author Elias Canetti. His lifelong notes have been edited and published posthumously for the first time in 2014. Thanks to this edition Canetti's short texts and aphorisms can be focused as a textual laboratory in which he tries to model a language of death on experimental practices of natural sciences. The miniature series of experiments address the problem of death, not representable in discourses of cultural studies, system theory or history of knowledge, and in doing so, Canetti creates liminal texts at the margins of western concepts of (human) life, science and established textual form.


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