Philosophers have long puzzled over the nature of space, time, and matter. These inquiries led to the flowering of physics with the Scientific Revolution in the 17th century. Since then, the spectacular success of modern physics might appear to have made philosophy irrelevant. But new theories have created a new range of philosophical concerns: What is the shape of space? Is time travel possible? Is there a grand unified theory that unites all of physics?

As recently as 1990, it seemed plausible that the solar system was a unique phenomenon in our galaxy. Thanks to advances in technology and clever new uses of existing data, now we know that planetary systems and possibly even a new Earth can be found throughout galaxies near and far.

Imagine a region in space where the force of gravity is so strong that nothing - not even light - can escape. This phenomenon is a black hole: one of the most exotic, mind-boggling, and profound subjects in astrophysics. Nearly everyone has heard of black holes, but few people outside of complex scientific fields understand their true nature and their implications for our universe. No movie, novel, or other fictional treatment of black holes matches Professor Filippenko’s absorbing presentation of the actual science behind these amazing objects.

Game theory is the study of strategic decision-making in politics, sports, diplomacy, and a host of other areas, but especially in economics, where game theory flourishes. Understanding Economics: Game Theory introduces you to this fascinating field, which combines the fun and challenge of games with the logic of brain teasers. In 12 engaging half-hour lessons, Professor Jay R. Corrigan of Kenyon College analyzes such classic games as the prisoner’s dilemma and the hawk-dove game.

"It doesn't take an Einstein to understand modern physics," says Professor Wolfson at the outset of these 24 lectures on what may be the most important subjects in the universe: relativity and quantum physics. Both have reputations for complexity. But the basic ideas behind them are, in fact, simple and comprehensible by anyone. These dynamic and illuminating lectures begin with a brief overview of theories of physical reality starting with Aristotle and culminating in Newtonian or "classical" physics.

In this 24-lesson course aimed at non-scientists, noted particle physicist Dr. Don Lincoln of Fermi National Accelerator Laboratory covers more than a century of progress in physics, describing exactly how scientists reach the conclusions they do. He starts with the atom, which was long hypothesized but wasn’t definitively proven until a paper by Albert Einstein in 1905. That was just the beginning, as researchers probed ever deeper into the atom’s complex structure, leading to the weird findings of quantum mechanics.

Between 1861 and 1865, the clash of the greatest armies the Western hemisphere had ever seen turned small towns, little-known streams, and obscure meadows in the American countryside into names we will always remember. In those great battles, those streams ran red with blood-and the United States was truly born.

Look beyond the abstract dates and figures, kings and queens, and battles and wars that make up so many historical accounts. Over the course of 48 richly detailed lectures, Professor Garland covers the breadth and depth of human history from the perspective of the so-called ordinary people, from its earliest beginnings through the Middle Ages.

Nothing has had a more profound impact on the development of modern civilization than thermodynamics. Thermodynamic processes are at the heart of everything that involves heat, energy, and work, making an understanding of the subject indispensable for careers in engineering, physical science, biology, meteorology, and even nutrition and culinary arts. Get an in-depth tour of this vital and fascinating science in 24 enthralling lectures suitable for everyone from science novices to experts who wish to review elementary concepts and formulas.

The Science of Information: From Language to Black Holes covers the exciting concepts, history, and applications of information theory in 24 challenging and eye-opening half-hour lectures taught by Professor Benjamin Schumacher of Kenyon College. A prominent physicist and award-winning educator at one of the nation’s top liberal arts colleges, Professor Schumacher is also a pioneer in the field of quantum information, which is the latest exciting development in this dynamic scientific field.

England: From the Fall of Rome to the Norman Conquest takes you through the mists of time to the rugged landscape of the British Isles. Over the course of 24 sweeping lectures, Professor Jennifer Paxton of The Catholic University of America surveys the forging of a great nation from a series of warring kingdoms and migrating peoples. From Germanic tribes to Viking invasions to Irish missionaries, she brings to life an underexamined time and place.

Consider these commonly held scientific beliefs: Planetary orbits are fixed ellipses; we only use 10 percent of our brains; nothing travels faster than light; a thrown object’s trajectory is a parabola. They seem correct, but they’re all misconceptions that aren’t entirely accurate. There’s much more to the story than you think. These magnificent 24 lectures are devoted to busting myths, clearing up confusion, and giving you scientific epiphanies that could change how you think about your everyday world.

Guiding you chronologically through the life and times of this master statesman, Professor Shelden takes you from the dawn of Churchill’s political career to his final years in a much-changed geopolitical landscape. You’ll examine Churchill’s beginnings as a young liberal statesman, his rise to the Admiralty and his relentless push for an imposing naval force, his fight against the Nazis, his equally dramatic postwar career suspended between two different cold wars (against the Soviets and Britain’s Labour party), and more.

Locked inside the DNA of every species that ever lived are endless stories - about origins, ancestors, fate, and much more. Until recently, these secrets were completely inaccessible. But with the help of new technologies, scientists are now reading the hidden history of DNA, making remarkable discoveries about ourselves and our fellow species. Your gateway to this treasure trove of information is Unlocking the Hidden History of DNA, 12 informative and accessible lectures delivered by New York Times best-selling author Sam Kean.

Trace the growth of communism from Stalin’s consolidation of power to the establishment of communist regimes in Eastern Europe, China, Korea, Vietnam, and elsewhere in Communism in Power: From Stalin to Mao. These 12 half-hour lessons shed intriguing light on a revolutionary movement that played an outsized role in the 20th century and continues to shape 21st-century geopolitics.

My Big TOE: Awakening, written by a nuclear physicist in the language of contemporary culture, unifies science and philosophy, physics and metaphysics, mind and matter, purpose and meaning, the normal and the paranormal. The entirety of human experience (mind, body, and spirit) including both our objective and subjective worlds is brought together under one seamless scientific understanding.

Chemistry and Our Universe: How It All Works is your in-depth introduction to this vital field, taught through 60 engaging half-hour lectures that are suitable for any background or none at all. Covering a year’s worth of introductory general chemistry at the college level, plus intriguing topics that are rarely discussed in the classroom, this amazingly comprehensive course requires nothing more advanced than high-school math. Your guide is Professor Ron B. Davis, Jr., a research chemist and award-winning teacher at Georgetown University.

Richard Dawkins' brilliant reformulation of the theory of natural selection has the rare distinction of having provoked as much excitement and interest outside the scientific community as within it. His theories have helped change the whole nature of the study of social biology, and have forced thousands to rethink their beliefs about life.

How the Earth Works takes you on an astonishing journey through time and space. In 48 lectures, you will look at what went into making our planet - from the big bang, to the formation of the solar system, to the subsequent evolution of Earth.

We are in the midst of a global mental health crisis, and mental illnesses are on the rise. But what causes mental illness? And why are mental health problems so hard to treat? Drawing on decades of research, Harvard psychiatrist Dr. Chris Palmer outlines a revolutionary new understanding that for the first time unites our existing knowledge about mental illness within a single framework: mental disorders are metabolic disorders of the brain. Brain Energy will transform the field of mental health, and the lives of countless people around the world.

Astrophysicist Neil deGrasse Tyson has attracted one of the world’s largest online followings with his fascinating, widely accessible insights into science and our universe. Now, Tyson invites us to go behind the scenes of his public fame by unveiling his candid correspondence with people across the globe who have sought him out in search of answers. In this hand-picked collection of 100 letters, Tyson draws upon cosmic perspectives to address a vast array of questions about science, faith, philosophy, life, and of course, Pluto.

Hilarious, fascinating, and a roller coaster of dizzying, historical what-ifs, Napoleon's Hemorrhoids is a potpourri for serious historians and casual history buffs. In one of Phil Mason's many revelations, you'll learn that Communist jets were two minutes away from opening fire on American planes during the Cuban missile crisis, when they had to turn back as they were running out of fuel. You'll discover that before the Battle of Waterloo, Napoleon's painful hemorrhoids prevented him from mounting his horse to survey the battlefield.

Dr. Catherine Kleier invites us to open our eyes to the phenomenal world of plant life and to the process she calls “Natura Revelata”, the joy of celebrating and learning from the secrets of nature. As Dr. Kleier shares her knowledge with contagious excitement for her subject, she emphasizes the middle ground: Instead of focusing on cell microbiology or the study of ecosystems and habitats, she stresses the basic biology, function, and the amazing adaptations of the plants we see all around us.

In this illuminating audiobook, Tyson and coauthor James Trefil, a renowned physicist and science popularizer, take on the big questions that humanity has been posing for millennia - How did life begin? What is our place in the universe? Are we alone? - and provide answers based on the most current data, observations, and theories.

At the end of his career, Albert Einstein was pursuing a dream far more ambitious than the theory of relativity. He was trying to find an equation that explained all physical reality - a theory of everything. Experimental physicist and award-winning educator Dr. Don Lincoln takes you on this exciting journey in The Theory of Everything: The Quest to Explain All Reality. Suitable for the intellectually curious at all levels and assuming no background beyond basic high-school math, these 24 half-hour lectures cover recent developments at the forefront of particle physics and cosmology.

As recently as 1990, it seemed plausible that the solar system was a unique phenomenon in our galaxy. Thanks to advances in technology and clever new uses of existing data, now we know that planetary systems and possibly even a new Earth can be found throughout galaxies near and far.

"It doesn't take an Einstein to understand modern physics," says Professor Wolfson at the outset of these 24 lectures on what may be the most important subjects in the universe: relativity and quantum physics. Both have reputations for complexity. But the basic ideas behind them are, in fact, simple and comprehensible by anyone. These dynamic and illuminating lectures begin with a brief overview of theories of physical reality starting with Aristotle and culminating in Newtonian or "classical" physics.

Consider these commonly held scientific beliefs: Planetary orbits are fixed ellipses; we only use 10 percent of our brains; nothing travels faster than light; a thrown object’s trajectory is a parabola. They seem correct, but they’re all misconceptions that aren’t entirely accurate. There’s much more to the story than you think. These magnificent 24 lectures are devoted to busting myths, clearing up confusion, and giving you scientific epiphanies that could change how you think about your everyday world.

Charles Darwin's theory of organic evolution-the idea that life on earth is the product of purely natural causes, not the hand of God-set off shock waves that continue to reverberate through Western society, and especially the United States. What makes evolution such a profoundly provocative concept, so convincing to most scientists, yet so socially and politically divisive? These 12 eye-opening lectures are an examination of the varied elements that so often make this science the object of strong sentiments and heated debate.

Book coach and editor Molly McCowan takes you through the self-editing process in 13 detailed lessons, using a step-by-step method designed to reduce overwhelm and to structure the revision process in the most productive way possible. Working from the big to the little picture of your work, Molly shows you how to strengthen character development, find and fix plot holes, build stronger scenes, focus on smooth pacing and point-of-view issues, elevate your language, and much more.

Whether taken as a book of faith or a cultural artifact, the New Testament is among the most significant writings the world has ever known, its web of meaning relied upon by virtually every major writer in the last 2,000 years. Yet the New Testament is not only one of Western civilization’s most believed books, but also one of its most widely disputed, often maligned, and least clearly understood, with a vast number of people unaware of how it was written and transmitted.

Look beyond the abstract dates and figures, kings and queens, and battles and wars that make up so many historical accounts. Over the course of 48 richly detailed lectures, Professor Garland covers the breadth and depth of human history from the perspective of the so-called ordinary people, from its earliest beginnings through the Middle Ages.

Roughly 2,500 years ago, the Athenian people established a radical democracy in which power derived from the votes of everyday citizens. At a time when local governments ranged from oligarchy to tyranny, the elite classes of Athens gradually ceded power to the inexperienced masses, whose votes served as referendums for everything from taxation to war to welfare. The sequence of events that led to this development is astonishing, and the society that flourished under Athenian democracy is one of the greatest - even if greatly flawed - achievements in world history.

We have never before in human history been able to share so much about ourselves so quickly. Neither have we ever been so exposed to forces that want to take advantage of that capability. Taking Control of Your Personal Data will open your eyes to the surprising extent of that exposure and will discuss your options for keeping your personal data as safe as possible. Your instructor, Professor Jennifer Golbeck of the College of Information Studies at University of Maryland, College Park, will show you what really goes on behind the scenes with the data you share all day long.

Philosophers have long puzzled over the nature of space, time, and matter. These inquiries led to the flowering of physics with the Scientific Revolution in the 17th century. Since then, the spectacular success of modern physics might appear to have made philosophy irrelevant. But new theories have created a new range of philosophical concerns: What is the shape of space? Is time travel possible? Is there a grand unified theory that unites all of physics?

Between 1861 and 1865, the clash of the greatest armies the Western hemisphere had ever seen turned small towns, little-known streams, and obscure meadows in the American countryside into names we will always remember. In those great battles, those streams ran red with blood-and the United States was truly born.

Memory is, without a doubt, the most powerful (and practical) tool of everyday life. By linking both your past and your future, memory gives you the power to plan, to reason, to perceive, and to understand. Yet while all of us have an amazing capacity for memory, there are plenty of times when it seems to fail us. Why does this happen? And how can you fix it? In Scientific Secrets for a Powerful Memory, you’ll explore the real research on how memory functions - and then apply these findings to help you make better use of the memory abilities you have.

What can we still learn from C.S. Lewis? Find out in these 12 insightful lectures that cover the author's spiritual autobiography, novels, and his scholarly writings that reflect on pain and grief, love and friendship, prophecy and miracles, and education and mythology.

We rely on effective research in many areas of life, and at times our lives even depend on it. But what is it that makes research effective? Any good research rests upon, above all else, method. In these 24 dynamic lectures, you’ll discover the remarkable procedures and techniques that make research such a powerful tool. This brilliantly conceived course gives you a deep, detailed, and practical guide to proper research methods - methods that are broadly applicable to all kinds of research.