Reviews for Space and Time

The average rating for Space and Time based on 2 reviews is 4 stars.

Review # 1 was written on 2019-01-13 00:00:00 O. Sessoms FREE From Eternity to Here COMPATIBILITY TEST Read through the following dialogue between two people, A and B. Underline all the sentences which you can imagine saying yourself. ____________________________________________ A: What are you thinking? B: Have you ever wondered why the future is different from the past? A: What do you mean, different? B: Well, you can remember the past, but you can't remember the future. Why? A: Like déjà vu? B: No, not déjà vu. Really remembering the future. A: But the future doesn't exist yet. How can you remember something that hasn't happened? B: On the other hand, the only reason you think the past exists is that you can remember it. A: Hmm... maybe! But it would be very confusing to be able to remember the future. You'd have no reason to want to do anything. B: It's not just memory, it's everything! For example, you have photographs of things that have happened in the past, but you can't have a photograph of something that's going to happen in the future. A: But how could you have a photograph of something that's going to happen in the future? B: A camera takes pictures of things that happened in the past. Why couldn't a future-camera take pictures of things that happen in the future? A: Because you can't. It wouldn't work. B: But why not? A: What does that book say? B: It says we can tell the difference between past and future because we're close to the Big Bang. A: What's that got to do with it? B: Well, it's a bit complicated. Imagine that the universe stopped expanding after a while and then collapsed again--- A: Is it going to do that?? B: No, it isn't. But imagine it did. Now would the result look like the Big Bang, only backwards? A: I don't know. B: Well, it wouldn't! That's very interesting, isn't it? A: Let me have a look myself. Hm, hm, hm... so he's got this theory about baby universes that he developed with someone called Jennifer Chen. What's a baby universe? B: Ah, first you have to imagine that our own universe continues for several zillion years--- A: Wait, he dedicated the book to Jennifer! "To Jennifer, for all time". So he developed this weird theory with his girlfriend? That's so romantic! B: It might be a different Jennifer. Let me google it. A: It can't be. B: Oh, it is! His wife's also called Jennifer. Just a coincidence. A: How disappointing! ____________________________________________ Now count the total number of As and Bs in your answers. Mostly As: You are a normal person. Congratulations. Mostly Bs: You spend too much time thinking about things that no one understands. You might enjoy this book. Somewhere in between: Lower your entropy, goddammit. ____________________________________________ And so far we have... Mostly As: notgettingenough, Kat, Warwick, Lynne, Ted, Shayan Mostly Bs: Manny, Tatiana, Riku, Fionnuala, Matt, [Name Redacted], Ariel, Forrest, Shinjini, Saman, Kris, Samadrita, Sarah Lower your entropy, goddammit: Zahro, Ivonne, Stuti, Joe, Jim, Cecily, Kalliope, Rakhi, Eti, Elham, Mike Groot: Robert

Review # 2 was written on 2018-07-02 00:00:00 Heather Wright This is some very impressive stuff. I've read a lot of nonfiction science books that sometimes had equations but mostly did not, but what I really wanted was a cohesive drive, an arrow to spear right through some of the biggest questions of our time... such as What Is Time. Sean Carroll manages to keep things very sharp between what is perfectly understood and all of the theories that are somewhat understood, and the other Cosmology stuff that's mostly just baffling. :) Any way you look at it, though, this is not a book that gets derailed or goes off into super strange directions. He lays out all the foundations, from the opening definitions of Time and what we think it means, from the average to the rather advanced notions of space-time and curvature, Einstein's energy equation, speed of light, diliation, moving all the way to Black Holes. This is very solid stuff. Plus, we have a very coherent definition of Time as Entropy, showing us just how complicated it can get when time's arrow might just be the illusion that Hawking says it is. I really enjoyed that discussion. Of course, we come up with lots of possibilities and digressions that are always explored in SF, too, but most of these are just bylines, moving quickly by the Grandfather paradox, etc, to get right back on the main track. Yes. We have Equations. :) Fortunately, the author does a very good job about explaining them and even getting deeper into the extra areas that made this rather more interesting for me since I've read many science books and have heard most of this already. I recommend this for anyone interested in Time. :) Not time management. Just Time. :) We do touch rather heavily upon Cosmology by the end, too, which was a blast and a half, getting into many-universes theory and string theory, to name a few. And he makes it clear! :) Seriously. This was some sharp stuff. Very readable. It's not a general overview. You might say it's putting time's arrow right through the heart of a big question and staying on track all the way to the end.