I was granted an ebook ARC of Something Deeply Hidden by Sean Carroll by the Publisher Dutton on NetGalley to provide a fair and honest review.
See my full review and discussion on my YouTube Channel!
I am beyond grateful to be offered the opportunity to review this book. I just recently finished one of Carroll’s older books, and it is one of my favorites of the year. I know this book is already out. Nevertheless, the copy I was granted expires on the 31st of December, so intend to finish it before then to provide feedback for the copy I received. When I reviewed From Here to Eternity, I tried to review each part of the book. I think the result was a bit of mess; it was also a lot of work. Here, I will stop after each chapter to very briefly summarize his points and to discuss how effective it was as a chapter. Summarizing it will help me get a sense of how well I really understand it. Basically, I’m blogging my entire experience with the book. When I’m done, I’ll summarize my thoughts above my blogging experience (right after this).
I absolutely adored this book. I am so grateful to NetGalley for providing me with an e-ARC of this. I didn’t even realize it was already out, and I ended up using the audiobook (also amazing) to read the book. I still am happy I got the ARC because I may not have read it otherwise. I have only just started on NetGalley. I am a fan of Carroll, so I wanted the chance to review his newest book early. Even if it was already out, I may not have read it without the ARC because that was really the biggest motivator (the need to provide a review).
Otherwise, I might have read a different book by him because I was honestly very afraid of this book. The first time I saw the synopsis (prior to finding it on NetGalley), I read quantum mechanics and thought this was not for me. I have never understood it and was unlikely to start trying now. Then, with the added incentive, I decided to give it a try. Dear Sagan am I happy I did. I left this book feeling as though I actually understand quantum mechanics. Then add on the extra benefit of being beyond fascinated, intrigued, and excited by his discussion of Everett’s Many World’s hypothesis. I go in depth in my thoughts on that in my live blogging where I responded after each chapter. I would refer you there, jjoshh.com, if you are interested in reading that.
All in all, this book did everything I want from a science book. It challenged my fundamental way of thinking all the while in a clear and structured manner. What’s more, it is one that doesn’t shy away from the tough parts of science while not creating a story that completely hinges on your reader to have an expert level understanding to follow along. I highly recommend this book and Sean Carroll (and his podcast Mindscape). This will probably be one of my top 10 books of the year. 5/5 stars
I will probably do a review on my channel as well, but that will be in a week or so when I have time.
Rating Break Down
Writing Style: 10/10
Desire to Reread: 10/10
Final Rating: 4.785/5
Note, each rating is weighted based on personal importance (see blog for more details).
The book is already out, so I should be okay to quote it. Lastly, I am reading this via the e-arc in conjunction with the audiobook (on Scribd). The audiobook is narrated by Carroll himself, and it is very well done. If you haven’t already, check out his podcast, Mindscape where he gets guests to discuss leading topics in science. I mention that here because the first thing I noticed was how much the audiobook was like listening to this podcast. It feels natural well performed.
Carroll uses the Prologue of this book for a very simple purpose. He is here to talk to us about Quantum Mechanics, but before he does that, he has to make has to make us care. He takes a subject that, I suspect, most people assume is resolved, and explains why what we think we know is wrong. What’s more, he hints at how he intends to make us look at Quantum Mechanics in a brand new way. He does it in a way that highlights how skilled a science communicator he is, and it gets me beyond excited to dig deeper into this book.
Part One: Spooky
In Chapter 1, His first step is to explain exactly what quantum mechanics tells us, generally speaking, and where it sits within the realm of physics. Basically, it is a foundation chapter. He discusses how quantum mechanics compares to classical mechanics in how we go from a world of concise reality to one of probability. He sums it up as follows: “What we see when we look at the world [through quantum reality] seems to be fundamentally different from what actually is.” Quantum mechanics works similarly to classical; that is, the system is set up and is let to evolve. The difference comes with the act of measuring. The fundamental problem addressed in this chapter is to understand that quantum theory, as it currently exists, doesn’t explain how reality works only that it is how it is.
The concept seems simple enough, and his background feels like a good description of what quantum mechanics is. In Chapter 2, Carroll takes us on a journey to how this all came to be understood. He tries to make his point, stated in Chapter 1, that there is something missing in our understanding. Carroll explains the difference between epistemology which is the state of our knowledge versus ontology which is the state of reality. Essentially, this says there are ways of getting to the result without fully understanding how we got there. I get a little lost as he transitions to thinking about QM in a different manner. He treats the idea of a wave function as reality. where everything is literally a wave and when we observe it as otherwise, we aren’t observing a fact of reality, simply a piece of reality lacking a bigger picture. The impression I get from this is that the problem with QM isn’t an ontological one but an epistemological one.
I can’t pin point exactly how he goes from each point to the next, but I find his explanation overall effective. I’ve never quite understood what it meant to be a wave function. Now I think I do. Waves aren’t just a construct, they are a fact of reality, where reality acts fundamentally different than we perceive it in classical mechanics. That is, the universe is as much in a state of superposition as the quantum particles that make it up. That leads Carroll to the idea of Many Worlds, where many worlds are simply an extension of quantum theory. “The potential for such universes was always there,” and each world is a realization of that each position. This may be the best explanation of the many worlds theory that I’ve ever read (not a cosmologist). What’s more, Carroll doesn’t hold back that this could be wrong, and he takes the time to address other possibilities.
Chapter 3 felt like an introduction to quantum mechanics. Carroll provides a reader with the history of the science that lead to our current understanding. He concluded by explaining how the scientific community came to the understanding that quantum mechanics is fundamentally probabilistic despite many attempts to assign it a deterministic nature. It was a fine review, but I found myself wondering what the point of it all was until he spelled it out that they never really explored the implications. Overall, I can’t help leaving the chapter unsure what it means to be probabilistic. Ideally, that is the point; I just wish I could, as a reader, have ascertained his point without him spelling it out.
Carrol is an apt story teller and science communicator. He uses Chapter 4 to explore probabilities, or more specifically, the nature of uncertainty, further. It seems the most important thing to understand is that the wave and uncertainty descriptions are not a broad description that works with gaps of knowledge. The physics that governs this world is fundamentally different than the rules of classical mechanics. I’ve got a background in that area, and it makes sense to me.
He finishes his discussion by focusing on the nature of what it means to be a wave. It was probably the most difficult material he has covered yet but still easily understood. He gets into a conversation on spin that feels esoteric and a bit over my head. Luckily, he doesn’t leave us stranded. He uses the information to guide us in our understanding. The nature of waves is a confirmed fact. The act of measuring quite literally appears to alter the wave like nature of a “particle.” I think he explains it best but it is fascinating.
Chapter 5 is what feels like, a concise discussion of the nature of entanglement. It is a doozy. I’m here reviewing the material trying to make sense of what Carrol is saying, but I am having a tough time. It seems entanglement is when two electrons share the same spin. The trick is, their spins are in superposition, and they don’t consolidated until measured. The trick is, once one is measured then the other is guaranteed to be measured as such too. What I don’t get is how we know this isn’t a correlation; why must it be an entanglement.
If a photon is used to force particle a into a fixed spin that doesn’t change the spin of what it is entangled to, it only passes that entanglement on to the photon used to change the spin. That suggests a shared dynamical relationship not an intrinsic entanglement. I have to assume there is an independent way of identifying them as entangled.
My initial impression at the start of the chapter was that entanglement is the way the wave function of the universe (or of these two particles) is intertwined. That is more than a coincidental correlation. All that is to say, the chapter is complicated, and I hope it becomes clearer later in the book.
Part 2: Splitting
Chapter 6 was easier to read. It discusses the nature of decoherence and it’s implications on the many worlds hypothesis. I can’t say I left the chapter absolutely convinced, but it was a much more compelling story to read. Now we are getting into the nitty gritty.
Chapter 7 tackles the nature of probability and the effect on the multiverse. I think the first very compelling point was how it doesn’t feel like we live in a multi-world universe, but the same was said about the earth rotating or the earth orbiting the sun. Sometimes, our intuitive senses aren’t enough. I found this chapter immensely fascinating. The nature of probability means all that can happen does happen. Now I’ve heard that before, but I’ve always wondered what the realistic effect is on the macro scale (vs micro/atomic).
If the position or spin of an electron can be in superposition, what difference does that make on the classical physics of the world. I still don’t really know, but one fantastic point Carroll makes is how we can discuss probabilities. Say we do a random number generator our interpretation of that will vary. If we assume the RNG is quantum (which Carroll’s actually is) then a string of 16 spin directions (1/0) will produce a world where every possible line of 1’s and 0’s exists. In that world, Carroll’s use of this list in his discussion would be directly effected by unlikely results like all 1’s or weird patterns. It’s fascinating to think of the different directions his book and life would take in those scenarios. It’s debatable how big of an effect it would have, but it’s a substantial example of a direct influence of these quantum superpositions on the macro world.
Carroll finishes the chapter exploring how we might differentiate between more likely scenarios. This part highlights my biggest problems with the book which my inability to comprehend the more esoteric discussions. That said, Carroll continues to keep us grounded by walking through each piece such that I leave understanding (I think) the points he is trying to make. Unfortunately, I don’t have the time to study what he’s saying to fully appreciate every step along the way.
The fascination continues in Chapter 8 as Carroll begins to attack, head on, the question of whether the Many Worlds perspective is (1) the most logical conclusion and (2) really science. The quintessential simplicity of the theory is that anything else would have to add on or change the laws of quantum mechanics as we understand it. Basically, if you want to deny the existence of an infinite number of worlds, you have to complicate our own. As far as occurs razor is concerned, that just doesn’t work. Then as far as science, it is said that a theory must be falsifiable, and one cannot deny that the law that implies the multi-world perspective is entirely falsifiable simply by disproving the laws of quantum mechanics.
Chapter 9 is dedicated to the opposing theories that have been proposed to counter the Everett Many-Worlds interpretation. I thought it was a great overview and comparison. To be fair, we have multiple theories condensed to one chapter with 2/3 of this book to talk about Everett’s view, but I thought it Carroll did a good job defending against them. Granted, I may struggle to explain this myself without further review.
What we got in Chapter 10 is really what I’ve been waiting for all along. He talks about the implications on us. He delves into the question of free will, consciousness, and whether these quantum processes can really be assumed to extend to the choices we make. He makes a compelling case that it is unlikely that our choices are in fact quantum. That is to say, the processes that govern it are probably not probabilistic. Nevertheless, he talks about opportunities that we might introduce such randomness into our decisions. We can use quantum number generators to help make decisions to ensure multiple versions of our-self, however minor.
Now, I came to this revelation last month, and ever since, I’ve been striving to make decisions by it. Right now, I’ve used it to decide which books (or the order by which) I read. This may be minor, but books can have profound effects on us. I can imagine a world where I read one book and not another and it seriously effecting me. This book is a prime example of that. I may expand on this discussion in another post, but I’ll summarize with how exciting I find this all to be. The ability to actively create multiple versions of one’s self is so enthralling to me.
Part 3: Spacetime
In Chapter 11 Carroll begins to explore what this actually means for reality. That is, where are the other worlds, and how are they connected to us. My understanding is that these states all coexist in the quantum realm, but there is something about our entangled selves that then experience these physical laws for our specific reality given. However, the others can be thought to be there, experiencing reality slightly different. I think he did a good job explaining this. It is still very abstract but overall a good take on how this relates to the greater universe.
I found Chapter 12 to be a bit esoteric. He seems to be discussing the nature of quantum field theory, and, while interesting, I didn’t understand the point as it relates to the Many Worlds interpretation. I think he was trying to highlight the fundamentally difference between the way reality works in quantum mechanics than in how we perceive reality. That is to say, particles aren’t strictly what we perceive them to be. Perhaps this suggests the same may be true for Many Worlds? It may be that it has nothing to with that and Carroll is branching off into another tangential area of research.
On that note, Chapter 13, the last chapter, is all about quantum gravity. He makes sure to be very clear: this is purely hypothetical. Quantum gravity may be an intriguing idea, but it is not yet on the same level as say even the Many Worlds interpretation which at least is based on an understood scientific idea. I think it did a really good job bringing this section to close. While it is very theoretical and ongoing research, I can better appreciate how chapter 12 was building up to this idea which is essentially that space, and maybe time, is emergent. That is, the nature of entanglement of particles brings space into existence as we perceive it. As such, that might explain why we perceive our world from a different world where the quantum state is a bit different.
Epilogue and Appendix
This was pretty straightforward close to the book. I like that he read the appendix (or selected parts) on the audiobook.