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'Clear and compact ... It's hard to fault as a brief, easily digestible introduction to some of the biggest questions in the Universe' Giles Sparrow, BBC Four's The Sky at Night , Best astronomy and space books of 2019: 5/5 All the matter and light we can see in the universe makes up a trivial 5 per cent of everything. The rest is hidden. This could be the biggest puzzle that science has ever faced. Since the 1970s, astronomers have been aware that galaxies have far too little matter in them to account for the way they spin around: they should fly apart, but something concealed holds them together. That 'something' is dark matter - invisible material in five times the quantity of the familiar stuff of stars and planets. By the 1990s we also knew that the expansion of the universe was accelerating. Something, named dark energy, is pushing it to expand faster and faster. Across the universe, this requires enough energy that the equivalent mass would be nearly fourteen times greater than all the visible material in existence. Brian Clegg explains this major conundrum in modern science and looks at how scientists are beginning to find solutions to it.
An award-winning science journalist details the quest to isolate and understand dark matter--and shows how that search has helped us to understand the universe we inhabit. When you train a telescope on outer space, you can see luminous galaxies, nebulae, stars, and planets. But if you add all that together, it constitutes only 15 percent of the matter in the universe. Despite decades of research, the nature of the remaining 85 percent is unknown. We call it dark matter. In The Elephant in the Universe, Govert Schilling explores the fascinating history of the search for dark matter. Evidence for its existence comes from a wealth of astronomical observations. Theories and computer simulations of the evolution of the universe are also suggestive: they can be reconciled with astronomical measurements only if dark matter is a dominant component of nature. Physicists have devised huge, sensitive instruments to search for dark matter, which may be unlike anything else in the cosmos--some unknown elementary particle. Yet so far dark matter has escaped every experiment. Indeed, dark matter is so elusive that some scientists are beginning to suspect there might be something wrong with our theories about gravity or with the current paradigms of cosmology. Schilling interviews both believers and heretics and paints a colorful picture of the history and current status of dark matter research, with astronomers and physicists alike trying to make sense of theory and observation. Taking a holistic view of dark matter as a problem, an opportunity, and an example of science in action, The Elephant in the Universe is a vivid tale of scientists puzzling their way toward the true nature of the universe.
The laws of thermodynamics drive everything that happens in the universe. From the sudden expansion of a cloud of gas to the cooling of hot metal, and from the unfurling of a leaf to the course of life itself - everything is directed and constrained by four simple laws. They establish fundamental concepts such as temperature and heat, and reveal the arrow of time and even the nature of energy itself. Peter Atkins' powerful and compelling introduction explains what the laws are and how they work, using accessible language and virtually no mathematics. Guiding the reader from the Zeroth Law to the Third Law, he introduces the fascinating concept of entropy, and how it not only explains why your desk tends to get messier, but also how its unstoppable rise constitutes the engine of the universe.
Advances made by physicists in understanding matter, space, and time and by astronomers in understanding the universe as a whole have closely intertwined the question being asked about the universe at its two extremesâ€"the very large and the very small. This report identifies 11 key questions that have a good chance to be answered in the next decade. It urges that a new research strategy be created that brings to bear the techniques of both astronomy and sub-atomic physics in a cross-disciplinary way to address these questions. The report presents seven recommendations to facilitate the necessary research and development coordination. These recommendations identify key priorities for future scientific projects critical for realizing these scientific opportunities.
In a revolutionary new theory, Dr. Robert Foot of the University of Melbourne argues that meteorites composed of mirror matter could impact with the Earth without leaving any ordinary fragments. Indeed, the theory seems to provide a simple explanation for the puzzling Tunguska event--the blast which destroyed a huge area of Siberian forest in 1908. While scientists have attributed this explosion to an ordinary meteorite, no traces of such an object have ever been found. Moreover, there are frequent smaller such events, occurring on a yearly basis, which are even more puzzling. Foot's new book lays clear the scientific case for mirror matter. It describes the fascinating evidence for its existence including, astronomical observations suggesting that most of our galaxy is made from a new form of matter--dark matter. It explains puzzling Jupiter sized planets only a few million miles from their host star, and the mysterious slowing down of spacecraft in our solar system. Remarkably, it is also possible that Pluto might even be a mirror world, which would explain various anomalous features of its orbit. Perhaps the most important consequence of all this--if true--is the possibility of actually extracting the mirror matter from the Tunguska impact site and other such sites on earth. Invisible asteroids and other cosmic bodies made of a new form of matter may pose a threat to Earth, agrees a noted Australian physicist. But the mirror matter idea has not attracted a huge following among physicists. In a recent UPI article, Howard Georgi of Harvard University says, "Foot's ideas have not attracted a huge following in the community that cares about these things, perhaps because the problems they solve, while interesting, are not the most critical puzzles that we are wrestling with." Nevertheless, mirror matter, if it exists, would be a completely new type of material with a potentially huge commercial value. Its scientific value would be of no less importance. FROM THE BACK COVER Nearly 50 years ago it was discovered that the fundamental particles, such as the electron and proton, have `left-handed' interactions; they do not respect mirror symmetry. This experimental fact motivates the idea that a set of `mirror particles' exist. The left-handedness of the ordinary particles can then be balanced by the right-handedness of the mirror particles. In this way mirror reflection symmetry can exist but requires something profoundly new. It requires the existence of a completely new form of matter called `mirror matter'. Remarkably the mirror matter theory is capable of simply explaining a large number of contemporary puzzles in astrophysics and particle physics. The evidence ranges from observations suggesting that most of the matter in the Universe is invisible, to unexpected properties of ghostly particles called `neutrinos'. This book explains this fascinating theory and its evidence at a level accessible to the non-specialist.
Seven years before Richard Preston wrote about horrifying viruses in The Hot Zone, he turned his attention to the cosmos. In First Light, he demonstrates his gift for creating an exciting and absorbing narrative around a complex scientific subject--in this case the efforts by astronomers at the Palomar Observatory in the San Gabriel Mountains of California to peer to the farthest edges of space through the Hale Telescope, attempting to solve the riddle of the creation of the universe. Richard Preston's name became a household word with The Hot Zone, which sold nearly 800,000 copies in hardcover, was on The New York Times's bestseller list for 42 weeks, and was the subject of countless magazine and newspaper articles. Preston has become a sought-after commentator on popular science subjects.
An extraordinary and challenging synthesis of ideas uniting Quantum Theory, and the theories of Computation, Knowledge and Evolution, Deutsch's extraordinary book explores the deep connections between these strands which reveal the fabric of realityin which human actions and ideas play essential roles.
In preparing the report, Astronomy and Astrophysics in the New Millenium , the AASC made use of a series of panel reports that address various aspects of ground- and space-based astronomy and astrophysics. These reports provide in-depth technical detail. Astronomy and Astrophysics in the New Millenium: An Overview summarizes the science goals and recommended initiatives in a short, richly illustrated, non-technical booklet.
This book brings together reviews from leading international authorities on the developments in the study of dark matter and dark energy, as seen from both their cosmological and particle physics side. Studying the physical and astrophysical properties of the dark components of our Universe is a crucial step towards the ultimate goal of unveiling their nature. The work developed from a doctoral school sponsored by the Italian Society of General Relativity and Gravitation. The book starts with a concise introduction to the standard cosmological model, as well as with a presentation of the theory of linear perturbations around a homogeneous and isotropic background. It covers the particle physics and cosmological aspects of dark matter and (dynamical) dark energy, including a discussion of how modified theories of gravity could provide a possible candidate for dark energy. A detailed presentation is also given of the possible ways of testing the theory in terms of cosmic microwave background, galaxy redshift surveys and weak gravitational lensing observations. Included is a chapter reviewing extensively the direct and indirect methods of detection of the hypothetical dark matter particles. Also included is a self-contained introduction to the techniques and most important results of numerical (e.g. N-body) simulations in cosmology. " This volume will be useful to researchers, PhD and graduate students in Astrophysics, Cosmology Physics and Mathematics, who are interested in cosmology, dark matter and dark energy.