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
 |  Average 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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The Inexplicable Universe: Unsolved Mysteries is rated 4.4 out of 5 by 155.
Rated 5 out of 5 by from Imagine the Possibilities! Dr. deGrasse-Tyson has an amazing capacity to take extremely complex subjects and distill them to their essence. He then outlines his thoughts in a straightforward, clear manner that reveals his thinking on the subject - and it's clear he has given these subjects a great deal of thought!
Date published: 2018-07-29
Rated 5 out of 5 by from The Inexplicable Universe The DVD is incredible. I wish I would have had a professor that was as gifted lecturer as Neil deGrasse Tyson.
Date published: 2018-04-25
Rated 5 out of 5 by from Segments were broken down efficiently This was great course, very happy I got this. The course is broken down into manageable segments that don't overwhelm the viewer making for easy break points.
Date published: 2018-04-19
Rated 5 out of 5 by from The Inexplicable Universe: Unsolved Mysteries I just purchase the course in a 4 course package. Neil degrade Tyson does his usual excellent presentation on all subjects of the course. It will be one of my treasured dvd's to watch many times to be able to grasp all it's content!
Date published: 2018-04-09
Rated 5 out of 5 by from Amazing! This held my attention 100% throughout each lecture. I think I've become addicted to your courses!
Date published: 2018-04-07
Rated 4 out of 5 by from Comples I enjoyed the speculations about the universe, although a lot of the science is esoteric
Date published: 2018-04-05
Rated 3 out of 5 by from The Inexplicable Universe I've purchased numerous courses and additionally viewed or listened to others that the local library has. Two thing made me uncomfortable with Mr. Degrasse. 1) he comes off as someone that is so full of himself, 2) in the first 3 of 6 lectures, he almost comes to a giggle when he refers to earlier peoples belief in that certain conditions are derived from God. I never got this from any other course I've purchased to listened to; he mad me feel very uncomfortable. This is the first time I'm submitting a review
Date published: 2018-03-08
Rated 5 out of 5 by from Funny and captivating Fascinating and great way to get introduced to important concepts that you can then ponder about and learn more on your own.
Date published: 2018-02-22
Rated 4 out of 5 by from Tyson's Skilled The professor has an amazing talent for conveying very complex issues in understandable ways. He is one of the best scientific communicators of our age. My criticism of this course is that he comes across as overly dismissive of religious people. Isaac Newton was a strong Christian, and the professor implies that this was a weakness or only a result of Newton's limited understanding. I wish Dr. Tyson had acknowledged that someone can be both religious and scientific or simply left this topic alone. Thankfully, this is a relatively small part of the course, and I was able to ignore it and still enjoy the rest of the content, which is skillfully presented in an educational and entertaining manner.
Date published: 2018-02-16
Rated 5 out of 5 by from Great, great Course. This was the first course I bought. I was overwhelmed by it. It was all I hoped it to be. A very exceptional orator, well thought out, easy to follow and extremely educational for the lay person.
Date published: 2018-02-05
Rated 5 out of 5 by from very engaging and educational Dr. Tyson is great. He has a way of communicating complex issues with clarity and humor. He makes science fun. I have read many books on cosmology and particle physics and Dr. Tyson’s explanation of elementary particles is the clearest and most concise I have encountered. Although the course purports to covers a few specific mysteries the background of the mysteries provides a good chunk of knowledge. I have viewed the DVD several times just for the entertainment value. This course is one of the best uses of a viewer’s time possible.
Date published: 2018-01-27
Rated 3 out of 5 by from I Found Nothing New I hate to write anything unfavorable related to what seems to be America's most popular face for modern science. I'm not a scientist, although I've always had an interest in science and have listened to quite a few Great Courses over the years, especially in the areas of science. Perhaps that was my downfall: I had heard too much. I honestly cannot remember a single new idea that was presented in this short, one-DVD six-lecture program. For me it turned out a disappointment and a waste of time. For someone just now developing some interest in modern science and its questions, perhaps it might be an interesting introductory course. I'm not really able to speak to that well myself, because it wasn't where I was at when I got this.
Date published: 2018-01-27
Rated 4 out of 5 by from Great Gift for an Astrophysicist This was a gift for our grandfather an astrophysicist. The course was a refresher, but not totally or completely current.
Date published: 2017-12-26
Rated 5 out of 5 by from Love it Love Dr Tyson, he makes astrophysics fascinating!!!
Date published: 2017-12-13
Rated 5 out of 5 by from Challenges your curiosity Unbelievably interesting! Fun to follow and to watch. Neil deGrasse Tyson is a great scientist but also an entertaining presenter. He makes you think! For instance: Scientific DNA analasys indicates that the DNA of humans varies only by 1% from the DNA of chimpanzees. Imagine, when foreign life from the universe visits us on earth and finds our DNA just 1% different from theirs ---- will they lock us up?
Date published: 2017-12-09
Rated 5 out of 5 by from Excellent course. Highly recommended. A Much See. This is an excellent course and is highly recommended. I will watch this course more than once.
Date published: 2017-12-03
Rated 5 out of 5 by from A wonderful whirlwind tour! A thoroughly enjoyable tour of a select number of topics still mystifying astrophysicists. The professor is engaging & has a knack for distilling complex facts into understandable concepts. The course is made even better by the careful addition of explanatory graphics; I also enjoyed the accompanying sounds/music etc., which again were balanced just right.
Date published: 2017-10-21
Rated 3 out of 5 by from A little too shallow How do you explain the mysteries of physic in 6 lectures? Superficially. As impressive as Professor Tyson's credentials are and as gifted as he is at communicating complexity to us normal folk, this course is just too short. I cannot recommend it to anyone that seeks the moments of enlightenment that I expect from The Great Courses. Perhaps try "The Theory of Everything" by Professor Lincoln. At 24 lectures it is more of a commitment but I sincerely believe it is more rewarding.
Date published: 2017-09-27
Rated 5 out of 5 by from So likable! The best thing (it's hard to choose just one) about Neal deGrasse Tyson's productions is that while he doesn't make a show of being humble, he truly is. He lets his brains and personality show and yet isn't making the whole program to be about him. The material was well chosen to fit his theme, he made it understandable yet fascinating, and I felt he was sharing it rather than "teaching" me something I did not know, or that only someone as brilliant as he could convey the interest of it all. He is probably the one man I would most like to have a nice long dinner with. Thanks for an enjoyable and educational course. Janet Knori
Date published: 2017-09-13
Rated 4 out of 5 by from Great course Neil deGrasse Tyson is an excellent communicator, and always worth listening to.
Date published: 2017-06-25
Rated 5 out of 5 by from An odd choice, but engaging Excellent! Articulate exposition , clear explanations, and fascinating!
Date published: 2017-06-04
Rated 5 out of 5 by from Extremely interesting & complete There was so much information in this, but presented in ways that I could understand and learn from--a great part!
Date published: 2017-05-06
Rated 1 out of 5 by from The Inexplicable Universe I have purchased more than 60 courses from the Teaching Company. But this course seems to be a complete failure. Instead of discussing a few topics in depth,this mentions each topics in a few minutes. They are incomprehensible to young people as well as any mature people. I hope I may get refund.
Date published: 2017-04-16
Rated 5 out of 5 by from The Inexplicable Universe EXCELLENT. Tyson is a superb speaker/lecturer, the best. He does a superior job of setting out the still unsolved mysteries of the universe, including the still unexplained slight deceleration of Pioneers 10 and 11 as they leave the solar system . My only complaint would be that the course is too short.
Date published: 2016-12-19
Rated 3 out of 5 by from Did You Ever Wonder? This was a very interesting "course" but much too short. I wish it had included even a brief discussion on paper. The possibilities suggested were intriguing; is anyone actually working on some of these ideas? I understand the difficulties of such research, but hope it continues. Let us hope that this inspires more people to consider the mystery of the universe!
Date published: 2016-12-12
Rated 5 out of 5 by from very nice little survey course There is irony here. For such an immense subject, this is a very short course. There naturally is a tremendous amount that we do not know about the incomprehensible vastness of the universe and the incomprehensible complexity of life. This course nicely summarizes the current state of our not knowing. Of course, because the entire course is only 3 hours long, no subject is covered in depth. The course inspires further exploration. In that regard, it serves its purpose well.
Date published: 2016-12-10
Rated 4 out of 5 by from Entertaining Overview This course lightly touches on a variety of scientific topics . From the course description I expected it to be thought provoking entertainment and that is exactly what Professor deGrasse Tyson delivers. The Professor presents the material with clarity and enthusiasm and therefor this course can be enjoyed by scientists and non scientists alike. As someone with a college scientific background, I would have liked a little more detail about the research and studies currently being done at the forefront of the various fields, but all in all this course was great fun to watch.
Date published: 2016-11-23
Rated 5 out of 5 by from Very Entertaining I found the presentation to be very sincere, with an entertaining delivery. Professor Tyson seemed passionate about the course material, and was interesting and humorous. He also took a philosophical approach at certain times, which lended to the material well. While it doesn't feature any information that dedicated students would not know, this is a great short course for the casual person interested in space or science in general. This course also seemed to have a higher production quality than others, not that it should be a major selling point.
Date published: 2016-11-16
Rated 4 out of 5 by from Short & Excellent Presentation of Tough Material! There are six (6) classes, so it's not like you're getting deep it relates to this course. And make no mistake about it, there is some challenging stuff in each of the six classes. But Neil d.T just presents so darn well! In fact, some of his enthusiasm and curiosity on a given topic is infectious, so don't be surprised if you decide you want to look deeper into one (or more) of the subjects. No, this course will not make you a "resident expert" on the material but it easily leads you in the direction to want to become one!
Date published: 2016-11-07
Rated 5 out of 5 by from The Inexplicable Universe: Unsolved Mysteries A most excellent view into the world that was never taught to me in school in the 70's. Will wonders never cease. I recomment it for everyone.
Date published: 2016-10-04
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