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Rare earth: why complex life is uncommon in the universe (Copernicus Ser.)
Par Peter D Ward. 2000
Paleontologist/geologist Ward and astronomer Brownlee outline their hypothesis that complex multicellular life--animals and higher plants--"is less pervasive in the universe…
than is...commonly assumed." The two scientists reexamine Earth's history to identify crucial attributes that have allowed the planet's rare, and perhaps unique, evolutionary achievements. 2000Chroniques des atomes et des galaxies
Par Hubert Reeves. 2007
"[...] Textes brefs [qui] constituent un véritable tour de force par la simplicité avec laquelle l'auteur présente notre compréhension du…
cosmos sans pour autant masquer la subtilité des notions évoquées : le Big Bang, la courbure de l'Univers, la matière et l'énergie " sombres ", les univers parallèles, le principe anthropique, les trous noirs, etc. Une remarquable mise à jour des plus récentes découvertes de l'astrophysique et de la cosmologie". -- 4e de couvAstronomy professor identifies common misconceptions about the cosmos. Topics range from false notions regarding distant galaxies to erroneous theories about…
what causes tides and seasons and which planet is the hottest. He emphasizes the origins of incorrect ideas, how to avoid them, and how to change them. 2001Simply Einstein: relativity demystified
Par Richard Wolfson. 2003
Physicist explains for nonscientists the underlying principles of Einstein's theory of relativity. Explores the history of ideas that culminated in…
Einstein's vision of a four-dimensional universe of relativistic space-time. The author anticipates frequently asked questions, discussing time travel, curved space, black holes, and new meanings for past and future. 2003Ce volume aborde un domaine controversé à propos de l'effet des ondes électromagnétiques dans notre vie quotidienne. L'essentiel de l'ouvrage…
détaille l'aspect délétère: le quart de celui-ci est consacré à une nouvelle discipline nommée bio-électromagnétisme (effets bénéfiques). L'auteur livre les résultats d'une enquête qui a duré au-delà d'une quinzaine d'annéesPetite histoire de l'Univers: du Big Bang à la fin du monde
Par Stephen Hawking. 2008
"C'est exactement ce que propose ce recueil de sept conférences sur le cosmos et la place que nous y tenons,…
avec cette idée que " la science devrait être compréhensible par tous et pas seulement par quelques spécialistes. " De la théorie de l'expansion de l'Univers à celle du Big Bang en passant par les trous noirs, la direction du temps ou les découvertes de Hubble, Hawking nous convie à un passionnant voyage." -- 4e de couvHistoire du monde en sept catastrophes
Par Hervé Ponchelet. 2007
"Si l'on rembobine le film de l'histoire du monde, de l'homme au Big Bang, tout s'enchaîne parfaitement bien. Par le…
jeu de l'évolution biologique, chimique et physique, l'homme apparaît comme l'ultime et imparable aboutissement d'un "projet" en germe dans l'explosion primordiale voici 13,7 milliards d'années. Illusion d'optique ! En réalité, du Big Bang à Homo sapiens, ce ne fut qu'une suite de hasards et de nécessités qui fait de nous, et du monde tel qu'il est, plutôt une incongruité, ou si l'on préfère, un "miracle". De l'explosion originelle, qui manqua de faire "pschitt" comme un pétard mouillé, jusqu'à l'éruption cataclysmique d'un volcan géant à Sumatra, voilà 80 000 ans, qui faillit bien nous rayer de la saga du vivant, Hervé Ponchelet a identifié sept catastrophes principales grâce auxquelles, paradoxalement, nous devons, en dépit de tout, d'être là. C'est cette histoire vraie qui est ici contée, débarrassée des croyances mais intégrant les convergences entre science et mythes, replaçant les découvertes et les découvreurs dans leur contexte et l'évolution des idées, précisément informée mais conçue et rédigée à l'intention du public le plus large. À défaut de savoir où nous allons, sachons mieux d'où nous venons." -- 4e de couvEinstein in time and space: A life in 99 particles
Par Samuel Graydon. 2023
Walter Isaacson's Einstein meets Craig Brown's 99 Glimpses of Princess Margaret , in this innovative biography of the famous physicist…
told in ninety-nine dazzling vignettes. Most of us would agree that Albert Einstein's name is synonymous with "genius" and that his likeness is often used as a shorthand for all scientists, appearing everywhere from cartoons to textbooks. He has become more myth than man. That being the case, how best to capture his essence? In Einstein in Time and Space , talented young science journalist Samuel Graydon answers that question with an illuminating mosaic—99 intriguingly different particles that cumulatively reveal Einstein's contradictory and multitudinous nature. Glimpsed among these shards: a slacker who failed every subject but math, a job seeker who couldn't get hired, a lothario who courted many women, and a charmer who was the life of the party. As brilliant as he was inconsistent, Einstein was simultaneously an avid supporter of the NAACP and the fight for civil rights and someone capable of great prejudice. He was loved by many, known by few, and inspirational to a generation of young physicists. Graydon reveals every corner of Einstein's world: the false reporting that rocketed Einstein to fame nearly overnight, his effect on people he met merely in passing, even the remarkable posthumous journey of the famed physicist's brain. Entertaining, comforting, bolstering, and shocking, Einstein in Time and Space is the unique story of a man who redefined how we view our universe and our place within itSincère ou tricheuse?: roman (J'ai lu #3017. Roman, ISSN 0296-0678)
Par Barbara Cartland. 1991
Devenez sorciers, devenez savants (Petite bibliothèque Payot #434. Voyageurs)
Par Georges Charpak. 2002
Neutron Transport: Theory, Modeling, and Computations (Graduate Texts in Physics)
Par Ramadan M. Kuridan. 2023
This textbook provides a thorough explanation of the physical concepts and presents the general theory of different forms through approximations…
of the neutron transport processes in nuclear reactors and emphasize the numerical computing methods that lead to the prediction of neutron behavior. Detailed derivations and thorough discussions are the prominent features of this book unlike the brevity and conciseness which are the characteristic of most available textbooks on the subject where students find them difficult to follow. This conclusion has been reached from the experience gained through decades of teaching. The topics covered in this book are suitable for senior undergraduate and graduate students in the fields of nuclear engineering and physics. Other engineering and science students may find the construction and methodology of tackling problems as presented in this book appealing from which they can benefit in solving other problems numerically. The book provides access to a one dimensional, two energy group neutron diffusion program including a user manual, examples, and test problems for student practice. An option of a Matlab user interface is also available.The Geroch-Held-Penrose Calculus: Fundamentals and Applications (SpringerBriefs in Physics)
Par Pedro Bargueño, Ernesto Contreras. 2023
This book offers a primer on the fundamentals and applications of the Geroch-Held-Penrose (GHP) calculus, a powerful formalism designed for…
spacetimes that occur frequently in the teaching of General Relativity. Specifically, the book shows in detail the power of the calculus when dealing with spherically symmetric spacetimes. After introducing the basics, a new look at all the classical spherically symmetric black hole solutions is given within the GHP formalism. This is then employed to give new insights into the Tolman-Oppenheimer-Volkoff equations for stellar structure, including a derivation of new exact anisotropic fluid solutions. Finally, a re-writing of some essential features of black hole thermodynamics within the GHP formalism is performed. The book is based on the authors' lecture notes, used in their undergraduate and graduate lectures and while supervising their upper undergraduate and graduate students. To fully benefit from this concise primer, readers only need an undergraduate background in general relativity.Advances to Homomorphic and Searchable Encryption
Par Stefania Loredana Nita, Marius Iulian Mihailescu. 2023
This book presents the current state of the literature on the fields of homomorphic and searchable encryption, from both theoretical…
and practical points of view. Homomorphic and searchable encryption are still relatively novel and rapidly evolving areas and face practical constraints in the contexts of large-scale cloud computing and big data.Both encryption methods can be quantum-resistant if they use the right mathematical techniques. In fact, many fully homomorphic encryption schemes already use quantum-resistant techniques, such as lattices or characteristics of polynomials – which is what motivated the authors to present them in detail.On the one hand, the book highlights the characteristics of each type of encryption, including methods, security elements, security requirements, and the main types of attacks that can occur. On the other, it includes practical cases and addresses aspects like performance, limitations, etc. As cloud computing and big data already represent the future in terms of storing, managing, analyzing, and processing data, these processes need to be made as secure as possible, and homomorphic and searchable encryption hold huge potential to secure both the data involved and the processes through which it passes.This book is intended for graduates, professionals and researchers alike. Homomorphic and searchable encryption involve advanced mathematical techniques; accordingly, readers should have a basic background in number theory, abstract algebra, lattice theory, and polynomial algebra.Von der Relativitätstheorie zu den Maxwell-Gleichungen
Par Jan-Markus Schwindt. 2023
Die Elektrodynamik wird meistens in der historisch orientierten Reihenfolge behandelt, in der das elektrische und magnetische Feld zunächst als separate…
Objekte eingeführt und schließlich über die Maxwell-Gleichungen miteinander verknüpft werden. Die Lorentz-Symmetrie der Theorie und die Vereinigung der beiden Felder im Feldstärketensor werden üblicherweise erst am Ende gezeigt, obwohl sich die Gleichungen dadurch vereinfachen und sie erst so in allen Bezugssystemen gelten.Damit durchläuft der Studierende zwar die historische Entwicklung, muss aber dann zum Ende der Vorlesung alles rückblickend verstehen und neu einordnen. Dieses Buch geht den umgekehrten, deduktiven Weg, der die Elektrodynamik von vornherein auf das Fundament der Speziellen Relativitätstheorie stellt und von da aus – gegenüber dem üblichen Vorgehen sozusagen "rückwärts" – die bekannten Phänomene und Zusammenhänge ableitet. Dieses Vorgehen erlaubt eine wesentlich straffere und – was die Rolle des Elektromagnetismus im Gesamtzusammenhang der Theoretischen Physik angeht – klarere Behandlung.Superfluid: How a Quantum Fluid Revolutionized Modern Science
Par J. G. Weisend II. 2023
Unless you are a specialist or watch a lot of obscure YouTube videos you have probably never heard of He…
II or superfluid helium. This substance, a unique liquid form of the element helium, is produced and used in multi-ton quantities to enable much of modern science. Altogether, He II is at the heart of more than a dozen large scale scientific facilities world-wide representing an investment of tens of billions of dollars. It cools the magnets and cavities that contain and accelerate the particle beams at the Large Hadron Collider and is also used in accelerators for the study of rare isotopes and nuclear astrophysics. This little known liquid is, in reality, one of the enabling technologies of the future. A manifestation of quantum mechanics, He II exhibits amazing behaviors. It can flow up the side of a container against gravity, it can move through small openings without friction, and it can transfer heat extremely efficiently via a mechanism not seen elsewhere in nature. This book tells the story of He II. It describes the discovery of the fluid, the observation and understanding of its behavior, the development of underlying theory and the evolution of He II from a laboratory curiosity to an industrial-scale coolant. The current and possible future applications of He II are described. Like all science and engineering, the story of He II is a human story and the role that personalities, politics, communication, cooperation and competition play in the development of He II is captured here as well. World-famous physicists such as Lev Landau, Richard Feynman, Peter Kapitza and Kurt Mendelssohn are key players in the story, while secret police from two different countries have a walk-on role. This work is meant for the general reader. Without assuming any expertise in physics, engineering or mathematics, it illuminates for the general public a little-known area of science and engineering and shows why it matters. As it turns out, it’s also a good story.