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The Inexplicable Universe: Unsolved Mysteries

The Inexplicable Universe: Unsolved Mysteries

Neil deGrasse Tyson, Ph.D.
Hayden Planetarium

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The Inexplicable Universe: Unsolved Mysteries

Course No. 1816
Neil deGrasse Tyson, Ph.D.
Hayden Planetarium
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Course No. 1816
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Course Overview

Everything we now know about the universe—from the behavior of quarks to the birth of entire galaxies—has stemmed from scientists who’ve been willing to ponder the unanswerable. And with the advent of modern science, great minds have turned to testing and experimentation rather than mere thought as a way of approaching and grappling with some of the universe’s most pressing and vexing dilemmas.

So what is our latest picture of some of the most inexplicable features of the universe? What still remains to be uncovered? What are some of the next avenues of exploration for today’s chemists, physicists, biologists, and astronomers?

Pondering the answers to these and other questions is a great way to

  • appreciate the grandeur and complexity of the world around you,
  • better understand and discuss news and developments in science, and
  • spark further interest in some of science’s many exciting areas of study.

“We know a lot about the universe. But there’s even more that we don’t know,” says astrophysicist and Professor Neil deGrasse Tyson, director of the Hayden Planetarium, an award-winning lecturer, and one of the world’s foremost experts on the secrets of the universe. And his course The Inexplicable Universe: Unsolved Mysteries is the perfect gateway into this mind-bending and eye-opening subject. This visually stunning course, which has been honored with a 2013 Telly Award for Outstanding Educational Program, features six self-contained lectures that transport you on a marvelous journey to the frontiers of the known (and unknown) universe and introduce you to tantalizing questions being addressed by the world’s top scientists. Undeniably engaging and fascinating, this lecture series is a wonderful entrée to scientific pursuits that lie at the very heart of the history and nature of our universe.

An Informed Scientific Conversation

Central to The Inexplicable Universe is the way it takes you deep into hidden layers of the universe in a manner that is extremely accessible. Rather than a stern lecture given before a podium complete with confusing mathematics, Professor Tyson’s lectures have the feel of an informed conversation that manages to be both thorough and easy to grasp.

With each of the inexplicable mysteries he lays bare for you, Professor Tyson

  • introduces you to the history behind it,
  • lays out the science that has helped us grasp it,
  • explains what researchers have discovered to date, and
  • reveals what we have yet to discover.

And while the topics explore subjects in everything from quantum mechanics to cosmology to string theory, you’ll never feel overwhelmed by what you’re learning. In fact, you’re more likely to find yourself intrigued by just how much we know—and curious about what the near future will possibly reveal.

Explore Fascinating Territory

So what territory will you chart in this course? Here are some of the inexplicable ideas you’ll investigate in these lectures.

  • Neutrinos: Discovered in 1956, these fast-moving, ghostlike particles are made in abundance in the sun’s core. They hardly interact with matter; it takes a light-year’s worth of lead (5.8 trillion miles) to stop a neutrino. Not only that, but 65 billion neutrinos pass through every centimeter of your body that’s facing the sun every second of every day.
  • String theory: This astounding theory offers the hope of unifying all the particles and forces of physics. In the past several decades since the dawn of string theory, it’s been imagined that all the fundamental particles we see and measure are just the manifestation in our dimension of strings vibrating in higher dimensions and at different frequencies.
  • Quantum foam: This idea posits that when the fabric of space and time is so tightly curved on itself, space-time is less a smooth curve and more like the froth on a latte. In this state of matter and energy, quantum fluctuations can spawn entire universes, each with slightly different laws of physics within them!

In addition, you’ll also

  • get a peek at what it would be like to travel through a black hole,
  • ponder the possibility that life on Earth originated in debris from Mars,
  • probe the supposed existence of multiple universes, and
  • even imagine the possible end of the universe itself.

A One-on-One Chat with a Renowned Science Educator

Professor Tyson is renowned throughout the scientific community and the media for his vast knowledge, his penetrating insights, and his amazing ability to make even the most intimidating areas of science accessible, engaging, and—most of all—enjoyable. He brings the same inviting tone and sharp intellect to The Inexplicable Universe as he does to his range of media appearances on popular television programs, including The Daily Show with Jon Stewart, The Tonight Show with Jay Leno, and Real Time with Bill Maher.

Professor Tyson’s lectures also feature expertly crafted animations, explanatory graphics, and other instructive visual elements designed to better explain to you some of the grand, intricate ideas being discussed.

With The Inexplicable Universe, you’ll feel as if you’re participating in an exclusive chance to sit one-on-one with this renowned science educator and have a provocative, intriguing, and illuminating conversation. No other learning experience—including the most detailed science textbook—can bring you this close to interacting with an expert about the mysteries of the universe around you.

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6 lectures
 |  31 minutes each
  • 1
    History’s Mysteries
    Science history is filled with puzzling mysteries that were only solved with modern science’s focus on experimentation instead of thought. Here, take a closer look at concepts that were once unexplainable but, thanks to modern physics, are now better understood. You’ll focus on two such former mysteries: the existence of an invisible “aether” through which light and sound were believed to travel and the orbit of Mercury, which seemed (to earlier scientists) to violate Newton’s fundamental laws of motion. x
  • 2
    The Spooky Universe
    Did you know that electrons, discovered in 1897, have never actually been observed by scientists? Or that quarks can only be studied in pairs? Or that as you travel faster or find yourself in a higher gravity, time ticks more slowly for you? Delve into these and other mind-warping facts and insights about the fundamentals of matter in a lecture that covers everything from particle physics to quantum tunneling to thermonuclear fusion. x
  • 3
    Inexplicable Life
    Join Professor Tyson on a fascinating investigation of the possible origins of life in the universe. Why was Jupiter believed to be a good environment for life in the 17th century? Why is there only one single “tree of life” on Earth instead of multiple ones? How do extremophiles help scientists study life’s genesis? Could life have come to Earth from another planet? And what do we mean when we hope to find examples of life that is “intelligent”? x
  • 4
    Inexplicable Physics
    Among the many topics you’ll learn about in this lecture are the discovery of more elements on the periodic table; muon neutrinos, tao particles, and the three regimes of matter; the secrets of string theory (which offers the hope of unifying all the particles and forces of physics); and even the hypothetical experience of traveling through a black hole. x
  • 5
    Inexplicable Space
    Scientists have made astounding progress in their grasp of the universe. But what remains to be understood? Investigate some perplexing aspects of space that science has uncovered in the last half-century. Learn about the mysterious trajectory of the Pioneer spacecraft (known as the “Pioneer anomaly”). Explore two of the longest-standing problems in astrophysics: dark matter and dark energy. And even try to map the shape of space-time. x
  • 6
    Inexplicable Cosmology
    Take a fascinating trip through dimensions higher than our own. You’ll discover how quantum physics and string theory have opened our eyes to the possibilities of quantum foam, the multiverse, antimatter, and tachyons. Also, join Dr. Tyson for a preview of the long-term fate of the universe (including the collision of galaxies, the burning out of stars, and the decay of orbits into black holes). x

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Your professor

Neil deGrasse Tyson

About Your Professor

Neil deGrasse Tyson, Ph.D.
Hayden Planetarium
Dr. Neil deGrasse Tyson is the Frederick P. Rose Director of the Hayden Planetarium at the American Museum of Natural History in New York. He is also a research associate in the Department of Astrophysics at the museum. Professor Tyson earned his undergraduate degree in Physics from Harvard University and his Ph.D. in Astrophysics from Columbia University. Dr. Tyson has written prolifically for the public, including a series...
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Rated 4.4 out of 5 by 78 reviewers.
Rated 4 out of 5 by Interesting introductory course While I agree with other reviewers that I wish there was more depth to the course, I think it is a great introduction to opening up one's mind to the mysteries of science and the universe we live in without being overwhelming. The presenter is entertaining and enthusiastic. The material is the tip of the iceberg. This course and another Great Course, "12 Essential Scientific Concepts", led me to order more in-depth Great Courses covering black holes, dark matter, superstring theory, genetics, and convergence. "The Inexplicable Universe" has great value in getting the viewer to explore the wealth of knowledge available . I intend on showing it to my grandson when he gets a little older to get him interesting in science. September 29, 2015
Rated 2 out of 5 by Too basic There's little substance to this course and it is certainly not at a college level, as are most of The Great Courses lectures. The lecturer, while charming, was too overly dramatic for me--exhibiting constant repetition and "dramatic" pauses. Very disappointing. July 18, 2015
Rated 5 out of 5 by More like this, please I know others have downgraded this series because of its simplicity, but it was absolutely perfect for my audience, a weekly class of seniors, most of whom do have advanced degrees, who want to continue learning, but not necessarily at the very structured university level. We all enjoyed Dr. Tyson's warmth, his presentation, and the information presented. Only one attendee had a physics degree and we were able to ask her questions at the end of each lecture. I was surprised at the level of audience involvement following Dr. Tyson's talks. The graphics are well done and added to our understanding of the concepts presented. Yes, it's simplified, yes, it's basic, and it's also stimulating. Most of the audience members commented at one time or another what an interesting and dynamic speaker Dr. Tyson is. July 2, 2015
Rated 5 out of 5 by Short, entertaining, and thought provoking Just like in the recent TV series Cosmos, deGrasse Tyson’s goal is to educate people and make them more interested in the topic he presents. He does so by appealing to the majority of viewers, and I think the majority has only a very basic understanding of the universe. He describes the topics probably as simple as they can get without complicated equations and with adequate examples. I think that if you already have advanced knowledge and you are looking to learn more, the course is probably not for you. That being said I think this is a great course that appeals to different ages with some or little knowledge. The interesting part of the course is that the focus is not only on the knowledge mankind has acquired through the centuries, but on how much we still do not know and that there are still many mysteries that wait to be discovered. Unlike in his older course "My Favorite Universe", where he talks in front of a classroom without much technical support, this presentation, that takes place in a room similar to a private living room, is well supported by graphics, and consequently much more entertaining and interesting to watch. The six lectures are each divided into four or five chapters, which gives each lecture a good structure and makes it easy to process the information. Many topics are thought provoking, like "Theological Implications" in lecture 1, "Intelligence" in lecture 3, or the "Long-term Fate of the Universe" in lecture 6. Overall it is a great course to bring all important topics of astrophysics in an understandable and entertaing way to the viewer. June 23, 2015
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