What will happen if (perhaps when) humanity makes contact with another civilisation on a different planet? In 1974 a message was beamed towards the stars by the giant Arecibo telescope in Puerto Rico, a brief blast of radio waves designed to alert extraterrestrial civilisations to our existence. Of course, we don't know if such civilisations really exist. For the past six decades a small cadre of researchers have been on a quest to find out, as part of SETI, the search for extraterrestrial intelligence. So far, SETI has found no evidence of extraterrestrial life, but with more than a hundred billion stars in our Galaxy alone to search, the odds of quick success are stacked against us. The silence from the stars is prompting some researchers to transmit more messages into space, in an effort to provoke a response from any civilisations out there that might otherwise be staying quiet. However, the act of transmitting raises troubling questions about the process of contact. In The Contact Paradox, author Keith Cooper looks at how far SETI has come since its modest beginnings, and where it is going, by speaking to the leading names in the field and beyond. SETI forces us to confront our nature in a way that we seldom have before – where did we come from, where are we going, and who are we in the cosmic context of things? This book considers the assumptions that we make in our search for extraterrestrial life, and explores how those assumptions can teach us about ourselves.

The inspiration for the Netflix series 3 Body Problem! Over 1 million copies of the Three-Body Problem series sold in North America PRAISE FOR THE THREE-BODY PROBLEM SERIES: “A mind-bending epic.”—The New York Times • “War of the Worlds for the 21st century.”—The Wall Street Journal • “Fascinating.”—TIME • “Extraordinary.”—The New Yorker • “Wildly imaginative.”—Barack Obama • “Provocative.”—Slate • “A breakthrough book.”—George R. R. Martin • “Impossible to put down.”—GQ • “Absolutely mind-unfolding.”—NPR • “You should be reading Liu Cixin.”—The Washington Post The Dark Forest is the second novel in the groundbreaking, Hugo Award-winning series from China's most beloved science fiction author, Cixin Liu. In The Dark Forest, Earth is reeling from the revelation of a coming alien invasion-in just four centuries' time. The aliens' human collaborators may have been defeated, but the presence of the sophons, the subatomic particles that allow Trisolaris instant access to all human information, means that Earth's defense plans are totally exposed to the enemy. Only the human mind remains a secret. This is the motivation for the Wallfacer Project, a daring plan that grants four men enormous resources to design secret strategies, hidden through deceit and misdirection from Earth and Trisolaris alike. Three of the Wallfacers are influential statesmen and scientists, but the fourth is a total unknown. Luo Ji, an unambitious Chinese astronomer and sociologist, is baffled by his new status. All he knows is that he's the one Wallfacer that Trisolaris wants dead. The Three-Body Problem Series The Three-Body Problem The Dark Forest Death's End Other Books by Cixin Liu Ball Lightning Supernova Era To Hold Up the Sky The Wandering Earth A View from the Stars At the Publisher's request, this title is being sold without Digital Rights Management Software (DRM) applied.

In a 1950 conversation at Los Alamos, four world-class scientists generally agreed, given the size of the Universe, that advanced extraterrestrial civilizations must be present. But one of the four, Enrico Fermi, asked, "If these civilizations do exist, where is everybody?" Given the fact that there are perhaps 400 million stars in our Galaxy alone, and perhaps 400 million galaxies in the Universe, it stands to reason that somewhere out there, in the 14 billion-year-old cosmos, there is or once was a civilization at least as advanced as our own. Webb discusses in detail the 50 most cogent and intriguing solutions to Fermi's famous paradox.

An introduction to the search for extra-terrestrial intelligence through the lens of Fermi's paradox, discussing methodology and potential solutions.

There are various arguments for the metaphysical impossibility of time travel. Is it impossible because objects could then be in two places at once? Or is it impossible because some objects could bring about their own existence? In this book, Nikk Effingham contends that no such argument is sound and that time travel is metaphysically possible. His main focus is on the Grandfather Paradox: the position that time travel is impossible because someone could not go back in time and kill their own grandfather before he met their grandmother. In such a case, Effingham argues that the time traveller would have the ability to do the impossible (so they could kill their grandfather) even though those impossibilities will never come about (so they won't kill their grandfather). He then explores the ramifications of this view, discussing issues in probability and decision theory. The book ends by laying out the dangers of time travel and why, even though no time machines currently exist, we should pay extra special care ensuring that nothing, no matter how small or microscopic, ever travels in time.