The nature and essence of Dark Matter and Dark Energy have become the central issue in modern cosmology over the past years. This extensive volume, an outgrowth of a topical and tutorial summer school, has been set up with the aim of constituting an advanced-level, multi-authored textbook which meets the needs of both postgraduate students and young researchers in the fields of modern cosmology and astrophysics.

This book describes some of the frontier problems of cosmology: our almost total ignorance of what the Universe is made up of, the mystery of its origin and its end. The book starts with a description of the historical events that led to the construction of the Big Bang model together with the stages that transformed the Universe from a very hot place to a very cold one, full with the structures that we observe today. These structures (stars, galaxies, etc.) constitute only 5% of the contents of the Universe. Concerning the remaining 95%, dubbed dark matter and dark energy, we know very little, and we have only indirect evidence of their existence. The text describes the story and the protagonists who showed the need for the existence of this 'missing matter', the observations, and puzzles they had to solve to understand that dark matter was not ordinary matter. The book describes the hunt for dark matter, carried out with instruments operating in space, on the Earth's surface, and in laboratories built in the bowels of the Earth. It also describes dark energy, which manifests itself in the accelerated expansion of the Universe, and appeared only a few billions of years ago. The book discusses why dark energy must exist and what its existence implies, especially for the future and the end of our Universe.

This book describes some of the frontier problems of cosmology: our almost total ignorance of what the Universe is made up of, the mystery of its origin and its end. The book starts with a description of the historical events that led to the construction of the Big Bang model together with the stages that transformed the Universe from a very hot place to a very cold one, full with the structures that we observe today. These structures (stars, galaxies, etc.) constitute only 5% of the contents of the Universe. Concerning the remaining 95%, dubbed dark matter and dark energy, we know very little, and we have only indirect evidence of their existence. The text describes the story and the protagonists who showed the need for the existence of this "missing matter", the observations, and puzzles they had to solve to understand that dark matter was not ordinary matter. The book describes the hunt for dark matter, carried out with instruments operating in space, on the Earth's surface, and in laboratories built in the bowels of the Earth. It also describes dark energy, which manifests itself in the accelerated expansion of the Universe, and appeared only a few billions of years ago. The book discusses why dark energy must exist and what its existence implies, especially for the future and the end of our Universe.

Humanity's ongoing quest to unlock the secrets of dark matter and dark energy Heart of Darkness describes the incredible saga of humankind's quest to unravel the deepest secrets of the universe. Over the past thirty years, scientists have learned that two little-understood components—dark matter and dark energy—comprise most of the known cosmos, explain the growth of all cosmic structure and hold the key to the universe's fate. The story of how evidence for the so-called "Lambda-Cold Dark Matter" model of cosmology has been gathered by generations of scientists throughout the world is told here by one of the pioneers of the field, Jeremiah Ostriker, and his coauthor Simon Mitton. From humankind's early attempts to comprehend Earth's place in the solar system, to astronomers' exploration of the Milky Way galaxy and the realm of the nebulae beyond, to the detection of the primordial fluctuations of energy from which all subsequent structure developed, this book explains the physics and the history of how the current model of our universe arose and has passed every test hurled at it by the skeptics. Throughout this rich story, an essential theme is emphasized: how three aspects of rational inquiry—the application of direct measurement and observation, the introduction of mathematical modeling, and the requirement that hypotheses should be testable and verifiable—guide scientific progress and underpin our modern cosmological paradigm. This monumental puzzle is far from complete, however, as scientists confront the mysteries of the ultimate causes of cosmic structure formation and the real nature and origin of dark matter and dark energy.

Humanity's ongoing quest to unlock the secrets of dark matter and dark energy Heart of Darkness describes the incredible saga of humankind's quest to unravel the deepest secrets of the universe. Over the past forty years, scientists have learned that two little-understood components—dark matter and dark energy—comprise most of the known cosmos, explain the growth of all cosmic structure, and hold the key to the universe's fate. The story of how evidence for the so-called "Lambda-Cold Dark Matter" model of cosmology has been gathered by generations of scientists throughout the world is told here by one of the pioneers of the field, Jeremiah Ostriker, and his coauthor Simon Mitton. From humankind's early attempts to comprehend Earth's place in the solar system, to astronomers' exploration of the Milky Way galaxy and the realm of the nebulae beyond, to the detection of the primordial fluctuations of energy from which all subsequent structure developed, this book explains the physics and the history of how the current model of our universe arose and has passed every test hurled at it by the skeptics. Throughout this rich story, an essential theme is emphasized: how three aspects of rational inquiry—the application of direct measurement and observation, the introduction of mathematical modeling, and the requirement that hypotheses should be testable and verifiable—guide scientific progress and underpin our modern cosmological paradigm. This monumental puzzle is far from complete, however, as scientists confront the mysteries of the ultimate causes of cosmic structure formation and the real nature and origin of dark matter and dark energy.

Humanity's ongoing quest to unlock the secrets of dark matter and dark energy Heart of Darkness describes the incredible saga of humankind's quest to unravel the deepest secrets of the universe. Over the past thirty years, scientists have learned that two little-understood components—dark matter and dark energy—comprise most of the known cosmos, explain the growth of all cosmic structure and hold the key to the universe's fate. The story of how evidence for the so-called "Lambda-Cold Dark Matter" model of cosmology has been gathered by generations of scientists throughout the world is told here by one of the pioneers of the field, Jeremiah Ostriker, and his coauthor Simon Mitton. From humankind's early attempts to comprehend Earth's place in the solar system, to astronomers' exploration of the Milky Way galaxy and the realm of the nebulae beyond, to the detection of the primordial fluctuations of energy from which all subsequent structure developed, this book explains the physics and the history of how the current model of our universe arose and has passed every test hurled at it by the skeptics. Throughout this rich story, an essential theme is emphasized: how three aspects of rational inquiry—the application of direct measurement and observation, the introduction of mathematical modeling, and the requirement that hypotheses should be testable and verifiable—guide scientific progress and underpin our modern cosmological paradigm. This monumental puzzle is far from complete, however, as scientists confront the mysteries of the ultimate causes of cosmic structure formation and the real nature and origin of dark matter and dark energy.

'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.