All the matter and light we can see in the universe makes up a trivial five 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.

From the discovery of entirely new kinds of galaxies to a window into cosmic ‘prehistory’, Bothwell shows us the universe as we’ve never seen it before - literally. Since the dawn of our species, people all over the world have gazed in awe at the night sky. But for all the beauty and wonder of the stars, when we look with just our eyes we are seeing and appreciating only a tiny fraction of the universe. What does the cosmos have in store for us beyond the phenomena we can see, from black holes to supernovas? 

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.

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.

Today we are blessed with two extraordinarily successful theories of physics. The first is Albert Einstein's general theory of relativity, which describes the large-scale behavior of matter in a curved spacetime. The second is quantum mechanics. This theory describes the properties and behavior of matter and radiation at their smallest scales.

Gravity controls everything from the falling of an apple to the rising of ocean’s tides to the motions of the heavens above. If you’ve ever wondered how this most puzzling force works across our entire universe, you will be delighted by this 24-part course that is accessible to any curious person, regardless of your science education. No other product on the market presents the subject of gravity in as much detail as this course, which will follow the past 400 years of research and experimentation in the field.

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.

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. 

 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.  

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? 

Fundamental is a comprehensive beginner's guide to quantum mechanics, explaining not only the weirdness of the subject but the experiments that proved it to be true. Using a humorous and light-hearted approach, Fundamental tells the story of how the most brilliant minds in science grappled with seemingly impossible ideas and gave us everything from microchips to particle accelerators.

Space is the biggest, oldest, hottest, coldest, strangest thing a human can study. It's no surprise then, that the weirdest facts in science (not to mention the weirdest scientists themselves) are found in astrophysics and cosmology. If you're looking for instructions on how to set up your grandad's telescope this book probably isn't for you. In Astronomical, Tim James takes us on a tour of the known (and unknown) Universe, focusing on the most-mind boggling stuff we've come across, as well as unpacking the latest theories about what's really going on out there.

So you’ve fallen in love with space and now you want to see it for yourself, huh? You want to witness the birth of a star, or visit the black hole at the center of our galaxy? You want to know if there are aliens out there, or how to travel through a wormhole? You want the wonders of the universe revealed before your very eyes? Well stop, because all that will probably kill you.

In The Quantum Universe, Brian Cox and Jeff Forshaw approach the world of quantum mechanics in the same way they did in Why Does E=mc2? and make fundamental scientific principles accessible - and fascinating - to everyone.The subatomic realm has a reputation for weirdness, spawning any number of profound misunderstandings, journeys into Eastern mysticism, and woolly pronouncements on the interconnectedness of all things. Cox and Forshaw's contention? There is no need for quantum mechanics to be viewed this way.

Max Tegmark leads us on an astonishing journey through past, present and future, and through the physics, astronomy, and mathematics that are the foundation of his work, most particularly his hypothesis that our physical reality is a mathematical structure and his theory of the ultimate multiverse. In a dazzling combination of both popular and groundbreaking science, he not only helps us grasp his often mind-boggling theories, but he also shares with us some of the often surprising triumphs and disappointments that have shaped his life as a scientist.