Download or read book The Formation and Evolution of Cosmic Strings written by G. W. Gibbons and published by CUP Archive. This book was released on 1990 with total page 570 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Formation and Evolution of Cosmic Strings written by G. W. Gibbons and published by Cambridge University Press. This book was released on 1990-09-28 with total page 554 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cosmic Strings and Other Topological Defects written by A. Vilenkin and published by Cambridge University Press. This book was released on 1994 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive introduction to the role of cosmic strings and other topological defects in the universe.
Download or read book Decorative Furniture and Houschold Effech written by and published by . This book was released on 1933 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evolution of Cosmic Strings written by Vitaly Vanchurin and published by . This book was released on 2005 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: We investigate the evolution of finite loops and infinite strings as a part of a complete cosmic string network. We give dynamical arguments showing that the structures on infinite strings should obey a scaling law. We perform a simulation of the network which uses functional forms for the string position and thus is exact to the limits of computer arithmetic. The effective box size of our simulation is at least two orders of magnitude larger than what was previously reached. Our results confirm that the wiggles on the strings obey a scaling law described by universal power spectrum. The average distance between long strings also scales accurately with the time. Production functions of string loops do not show scaling. With low intercommutation probability p the true scaling regime is not reached until very late cosmic times, which makes it difficult to simulate such evolutions. Via the expansion of the box technique, we were able to reach scaling with a wide range of p. The physical correlation length shows no dependency on intercommutation probability, while the inter-string distance scales as p 1/3. Our results suggest that small-scale structures will also scale in an expanding universe, even in the absence of gravitational damping.
Download or read book Dynamical Evolution of Cosmic Strings written by and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The author have studied by means of numerical simulations the dynamical evolution of a network of cosmic strings, both in the radiation and matter era. Our basic conclusion is that a scaling solution exists, i.e., the string energy density evolves as t−2. This means that the process by which long strings dump their energy into closed loops (which can gravitationally radiate away) is efficient enough to prevent the string domination over other forms of energy. This conclusion does not depend on the initial string energy density, nor on the various numerical parameters. On the other hand, the generated spectrum of loop sizes does depend on the value of our numerical lower cutoff (i.e., the minimum length of loop we allow to be chopped off the network). Furthermore, the network evolution is very different from what was assumed before), namely the creation of a few horizon sized loops per horizon volume and per hubble time, which subsequently fragment into about 10 smaller daughter loops. Rather, many tiny loops are directly cut from the network of infinite strings, and it appears that the only fundamental scale (the horizon) has been lost. This is probably because a fundamental ingredient had been overlooked, namely the kinks. These kinks are created in pairs at each intercommutation, and very rapidly, the long strings appear to be very kinky. Thus the number of long strings per horizon is still of the order of a few, but their total length is fairly large. Furthermore, a large number of kinks favors the formation of small loops, and their sizes might well be governed by the kink density along the long strings. Finally, we computed the two-point correlation function of the loops and found significant differences from the work of Turok.
Download or read book Strings Matter written by Maria Sakellariadou and published by . This book was released on 1990 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evolution of Cosmic String Networks written by and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We summarize our new results on cosmic strings. These results include: the application of non-equilibrium statistical mechanics to cosmic string evolution, a simple ''one scale'' model for the long strings which has a great deal of predictive power, results from large scale numerical simulations, and a discussion of the observational consequences of our results. An upper bond on G[mu] of approximately 10/sup /minus/7/ emerges from the millisecond pulsar gravity wave bound. We discuss how numerical uncertainties affect this. Any changes which weaken the bound would probably also give the long strings the dominant role in producing observational consequences. 22 refs.
Download or read book The Evolution of Gauged Cosmic String Networks written by Graham Richard Vincent and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Formation and Evolution of Chiral Cosmic Strings written by Michael Roger Eng Huat Pickles and published by . This book was released on 2002 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evolution and Radiation from Superconducting Cosmic Strings written by V. Berezinsky and published by . This book was released on 1988 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Creation written by Barry R. Parker and published by Springer. This book was released on 2013-11-11 with total page 303 pages. Available in PDF, EPUB and Kindle. Book excerpt: I remember once watching a presentation of the creation of the universe in a planetarium. It was a fascinating experience: lights flashing, particles appearing to rush by as an explosive roar echoed throughout the planetarium. Then suddenly ... black ness. And after a few seconds ... tiny lights--stars blinking into existence. I tried to imagine myself actually going back to this event. Was this really what it was like? It was an interesting facsimile, but far from what the real thing would have been like. The creation of the universe is an event that is impossible to imagine accurately. Fortunately, this has not discouraged peo ple from wondering what it was like. In Creation I have attempted to take you back to the begin ning-the big bang explosion-so that you can watch the uni verse grow and evolve. Starting with the first fraction of a sec ond, I trace the universe from its initial dramatic expansion through to the formation of the first nuclei and atoms. From here I go to the formation of galaxies and the curious distribu tion they have taken in space. Finally I talk about the formation of elements in stars, and the first life on the planets around them.
Download or read book Cosmic Strings written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-08-16 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cosmic strings are linear topological defects which are predicted by some grand unified theories to form during a spontaneous symmetry breaking phase transition in the early universe. They are the basis for the only theories of galaxy formation aside from quantum fluctuations from inflation based on fundamental physics. In contrast to inflation, they can also be observed directly through gravitational lensing and their characterisitc microwave background anisotropy. It was recently discovered that details of cosmic string evolution are very differnt from the so-called standard model that was assumed in most of the string-induced galaxy formation calculations. Therefore, the details of galaxy formation in the cosmic string models are currently very uncertain. Bennett, David P. Unspecified Center NASA-CR-183367, NAS 1.26:183367, FERMILAB-CONF-88/85-A ...
Download or read book The Mathematical Theory of Cosmic Strings written by M.R. Anderson and published by CRC Press. This book was released on 2015-05-06 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a comprehensive survey of the current state of knowledge about the dynamics and gravitational properties of cosmic strings treated in the idealized classical approximation as line singularities described by the Nambu-Goto action. The author's purpose is to provide a standard reference to all work that has been published since the mid-1
Download or read book String Theory For Dummies written by Andrew Zimmerman Jones and published by John Wiley & Sons. This book was released on 2009-11-16 with total page 387 pages. Available in PDF, EPUB and Kindle. Book excerpt: A clear, plain-English guide to this complex scientific theory String theory is the hottest topic in physics right now, with books on the subject (pro and con) flying out of the stores. String Theory For Dummies offers an accessible introduction to this highly mathematical "theory of everything," which posits ten or more dimensions in an attempt to explain the basic nature of matter and energy. Written for both students and people interested in science, this guide explains concepts, discusses the string theory's hypotheses and predictions, and presents the math in an approachable manner. It features in-depth examples and an easy-to-understand style so that readers can understand this controversial, cutting-edge theory.
Download or read book String Theory in the Early Universe written by Rhiannon Gwyn and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gravitational Waves and Cosmic Strings written by Xavier Siemens and published by . This book was released on 2002 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cosmic strings are potential candidates for a variety of interesting cosmological phenomena such as gamma ray bursts, gravitational wave bursts and ultra high energy cosmic rays. The predictions of cosmic string models, however, depend sensitively on the so far unresolved question of the size of the small-scale structure. This thesis deals largely with this problem. First, I present a gravitational back-reaction model that assumes the interaction between all Fourier modes that make up a given perturbation on a long cosmic string. This calculation leads to the generally accepted value of the small scale structure cutoff. It also, however, leads to paradoxical behaviour when applied to two oppositely moving modes: As one of the modes is stretched conformally the gravitational power radiated approaches a constant. This result is in contradiction with our expectation for the straight string limit in which no power is radiated. A more careful investigation of this problem reveals that, in the case of two oppositely moving modes, the gravitational power is exponentially suppressed when the wavelengths of the modes are sufficiently different. I use this result to construct an improved gravitational back-reaction model in which modes of very different wavelengths do not interact. This model leads to a new small scale structure cutoff which is sensitive to the initial spectrum of perturbations present on the string. I also tentatively examine the consequences of this result for the evolution of cosmic string loops. Finally, I investigate the effect of the presence of small scale structure on the gravitational wave-bursts produced at cosmic string cusps.
