Welcome to the Universe MP3 CD – Unabridged, May 16, 2017

This is a wonderfully written book for someone who is interested in astrophysics, but does not have the knowledge to understand more technical books that are written for physicists. Three authors have contributed to this book, all prominent astrophysicists. I just received my copy, with its beautiful dust jacket, and couldn’t wait to start reading it! The first section of the book is written by Neil DeGrasse Tyson, who offers us a humorous approach to the vast subject of the universe. I only started reading the book yesterday, so I can’t as yet review the other authors, but from what I can tell by gleaning over the pages, it is impressive!I had originally been considering buying the audiobook version, but after reading comments that it was very difficult to understand “mathematical equations read out loud”, I decided to go for the printed version instead. I am so glad I did! As you can tell by my photos of a few sections of the book, there are color illustrations and diagrams, math equations, etc, that simply could not be relayed by words. Even if some pdf files are included with the audiobook version, I doubt that you would receive the quantity and quality of the illustrations in the actual physical book. I bought a “Used, Very Good” copy from Amazon Prime, but I would label it “Used, Like New.” It’s a pristine copy, dust jacket in mint condition! At $10.49, it was a bargain, considering that the book originally sold for $39.95, as shown on the inside of the cover!This book will offer you hours of fascinating information about the universe!

I really enjoyed this tour of the universe with a little bit of math thrown in (I have a PhD in math so still love proofs of scientific statements). I just have one little quibble (or maybe not so little). In Dr. Tyson's description of the Drake equation he uses the one example of life in the universe that we know of - the Earth - to estimate the percentage of planets in habitable zones - f sub L - that develop life. And I agree that it is probably very high (based on books such as A New History of Life by Peter Ward and Joe Kirschvink and The Vital Question by Nick Lane). However, Dr. Tyson used a different argument - the evolutionary advantage of intelligence - to come up with an estimate of < 0.1 for the estimate of those planets with life to develop intelligence. I would argue that those same books I quoted above pointed out an alternative argument. Again using the one example of a planet with life, those books point out that even though life developed relatively quickly on Earth, it was single celled life. Multi-celled life took another 2 billion years and only happened once (since all life can be traced to that one event). Hence could make a couple of conclusions here. One is that you obviously need multi-celled life to develop intelligence. And, second one could say that there is one chance in 4 billion of a planet with primitive life developing an intelligent species.Thus, instead of about 190 planets with intelligent life in our galaxy, I would argue that this number should be 190 x 2.5E-10 or .000000475. This means that 4 out of every 10 million galaxies would have an intelligent civilization. And, based on a recent estimate of a trillion galaxies in our observable universe, there would be only 4750 civilizations.I would love to get Dr. Tyson's view of this much more pessimistic estimate of the value of f sub I - the Drake equation's estimate of the number of planets with life that develop intelligent life.I should also point out my estimate above ignored other factors, i.e., multi-celled life wouldn't necessarily result in an intelligent species. However, I agree with Dr. Tyson's feeling that intelligence is an advantage in evolution and so that might almost be a 100% probability.-- Horace Heck

A wonderful and challenging read for non-scientists (such as myself). Getting just slightly dated, but that’s print media vs a rapidly developing field. Tyson, Strauss, and Gott achieve making this material digestible if you have just a little background reading in the subjects and are willing to put in the work.My only complaint is the end, in which Gott goes off on a bit of a tangent of opinions and conjecture, including a bit of Elon worship. I wonder if he would still back these statements today. Opinions are fine, but ending a textbook (which this is) like this is a real let down; like running a marathon to spend the last .2 miles in a swamp. Still, the journey is worth it and the rest of the book is certainly worth your time if you’re looking for a firmer grasp on things.

This is an interesting book, both in its content and in its concept. Three prominent astrophysicists have written a textbook on the subject of astrophysics for students at Princeton with little or no prior training in the physics and math upon which the subject is based. Based on the success of the course, the book is now being marketed to the general reading public, which is a noble experiment. I have a lifetime of prior experience in the type of math and physics upon which astrophysics is based, but no experience of applying that math and physics to the problems discussed in this book. I can imagine that a Princeton student, given some examples and some exercises (not included in the book), could work through most of the math at the level discussed, and the subject is sufficiently interesting to motivate them to do so (I found myself wanting to do this.) With my background, I could understand how it should be possible to work through the calculations that they described to “measure” the composition and temperatures of stars, the distances to distant galaxies, etc. However, I suspect that readers without at least a BS in Physics sort of background will feel that they are being asked to take a lot on faith, despite the authors’ efforts to the contrary. However, this is a breathtaking and profusely illustrated story of how stars and planets and galaxies are formed, evolve and die, of how the (perhaps multiple) universe is expanding, of the necessity of “dark” matter/energy, of the implications of relativity, the geometry of space-time and of how we have determined all of this.