Inside Science reviews: “The Big Picture” (Sean Carroll’s book) and “The Man Who Knew Infinity”

Here are excerpts from a new book review and movie review I’ve written recently for Inside Science News Service. I have a few additional thoughts about Sean Carroll’s book, below this excerpt.


Sean Carroll’s ‘Big Picture’ Tours Physics And Philosophy

In a new book, Sean Carroll brings together physics and philosophy while advocating for “poetic naturalism.”

Quantum physics, cosmology, existentialist philosophy and morality may seem like disparate subjects. But Sean Carroll, a theoretical physicist at Caltech, ties them all together into a cohesive and comprehensive worldview he calls “poetic naturalism.” He lays out his views while trying to find meaning in a vast and chaotic universe in his newly published book, “The Big Picture” (Dutton, Penguin Random House Inc.).

Having written two previous popular physics books as well as being active on Twitter and his blog, Carroll takes an interest in communicating complex scientific discoveries. In his new book, he describes some of the fundamental ideas in modern physics with a philosophical lens, while exploring life’s biggest mysteries: the origin of the universe and the meaning of life itself. At the same time, with references to Wile E. Coyote, Captain Kirk and “Bill and Ted’s Excellent Adventure,” he avoids an overly serious tone.

In recent years, prominent scientists like Neil deGrasse Tyson, Bill Nye and Stephen Hawking have downplayed the importance of philosophy or even denigrated it. Carroll is not among this crowd.

“There are a lot of scientists and science promoters who have said not entirely complimentary things about philosophy, but that misses the point about what it’s for,” Carroll said in an interview. “The purpose of philosophy is not to be the handmaiden of science.”

(Credit: Dutton, Penguin Random House, Inc.)

(Credit: Dutton, Penguin Random House, Inc.)

Though his Ph.D. is in physics, Carroll has a strong interest in philosophy as well, and minored in it in college. He sees philosophy as a method for interpreting science and for a deeper understanding of physical phenomena. He uses philosophical concepts such as causality, determinism and mind-body dualism to explore everything from the tiniest subatomic particles to the accelerating expansion of the universe — as well as the role humans play somewhere in between.

For Carroll, naturalism means that there’s one world, the natural world, it obeys the laws of nature, and you can discover it using science. To this he adds that “there are many ways of talking about the world,” stories that people can tell to make sense and meaning of the world and their place in it. He even address issues of free will, consciousness, ethics, and life after death…

…The situation becomes murkier when Carroll discusses quantum mechanics, the interpretation of which has continually generated debates among physicists and philosophers since Max Planck and Albert Einstein discovered light “quanta” in the early 20th century. Physicists interpret quantum systems with probabilities: for example, for a hydrogen atom, the electron doesn’t have a particular position or momentum, but if someone measures them, it has probabilities of being observed in particular states.

Carroll supports the controversial “many-worlds interpretation” in which every quantum possibility is literally a separate world (or universe). We happen to live in one of them, and we have no way of seeing or even confirming the existence of the many unobservable parallel universes. This interpretation seems to conflict with his claim of endorsing a “sparse ontology,” which would mean accepting only a few fundamental concepts for describing the natural world.

“What I took Carroll to be promoting was a kind of ‘verificationism’: what is true is what can be measured,” said Elise Crull, philosopher of science at the City College of New York. “But what counts as ‘measurable,’ and how we distinguish theoretical from observational statements, are complex issues.” This is why, she argues, philosophers considered the view problematic and abandoned it long ago…

[For more, check out the entire story in Inside Science, published on 19 May 2016. Thanks to Chris Gorski and Emily DeMarco for editing assistance.]

Additional thoughts:
I think Carroll’s book does a great job of tying together so many disparate concepts, and I commend his efforts to communicate philosophical ideas. It’s important to encourage people to think and talk about “what it all means.” However, I think Carroll comes across as a little overconfident sometimes, as if he has all the answers. (But he’s more modest at other times.) Furthermore, he’s clearly more of an expert on the physics than the philosophy. His philosophical views don’t seem very nuanced or even self-consistent, and his book lacked a discussion of some important questions. (Exactly what are “laws” of nature and what do they tell us about how things actually behave? How do we assess the simplicity or predictive or explanatory power of a scientific theory?) He also missed some influential philosophers and physicists who have studied “scientific realism” in the context of cosmology and quantum physics for decades.

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Thoughts on “Interstellar” and Questions it Raises

I finally went and saw Christopher Nolan’s Interstellar a couple days ago. It’s definitely an entertaining and thought-provoking movie, and it’s worth seeing in a theater. This post won’t really be a review of the film, but I’ll give you a few of my thoughts about it and implications of it for our role in the universe. I’m interested in hearing your response to the movie as well. It raised some big and important questions that we humans should explore further. (Note: this post includes a few “spoilers,” so consider yourself warned.)

First of all, if you haven’t seen 2001 or Contact already, then you should rectify that immediately! They’re both excellent, and Interstellar was made with many connections and homages to them…so turn off your computer or tablet or brain implant or whatever you’re reading this with, and go check out those movies! You can come back to this blog later.

Also, if you’re interested in checking out other astronomers’ responses to the movie, you can read the excessively critical review and mea culpa by Phil Plait, the interesting tweets and more tweets by Neil deGrasse Tyson, and this article in Wired magazine by Adam Rogers (and thanks to Lynne Friedmann for giving it to me).


Why are astrophysicists discussing or questioning some aspects of the film? It’s because the filmmakers consulted Kip Thorne and did attempt to get the physics right, and because it’s the big space movie of the year, like Gravity was last year. In my opinion, they did do a pretty good job on many issues, though I wasn’t so sure about a couple others: for example, I’m not sure whether all the time dilation effects were calculated accurately (though their take on the “twin paradox” was interesting), and I’m skeptical about Matt McConaughey’s character’s experience in the black hole (which is the circular saw-shaped image above). And deGrasse Tyson made an accurate and important observation that bothered me too: “Mysteries of #Interstellar: Stars vastly outnumber Black Holes. Why is the best Earthlike planet one that orbits a Black Hole”?

I’m not going to get into these physics issues much here. (I’m happy to try to answer any questions you might have though—just post a comment or contact me on Twitter.) Instead, I’m more interested in exploring questions the movie raised. For example, how much of a priority is space exploration to us as a society? How difficult would it be to find another potentially habitable planet—and what are our criteria for “potentially habitable”? How would we traverse these great distances? How do we transport people (and necessary equipment and supplies) so that they can survive for long periods far from Earth—in spacecraft, space stations, or colonies? How vulnerable is our own planet and which vulnerabilities should we be trying to address? How might we eventually contact or even meet alien species, and what would we tell or ask them? Who would do the talking or asking? Will we behave with empathy or will we act like conquerors? What are own roles and responsibilities as Earthlings and citizens of the cosmos?

(We also learned a few fun things from the movie, such as: wormholes can be convenient; books get pushed off of shelves by space ghosts; NASA will survive even during the worst of times; and watch out if you land on an ice planet and find Matt Damon.)

It’s easy to become focused and fixated on short-term and local problems, as they can seem the most pressing. That’s totally understandable, but we as a society can’t forget the big long-term picture. What are our objectives and priorities as a global community? What do we want to achieve, and how can we work toward those goals and help future generations to realize them?

In the movie, a runaway Dust Bowl—presumably due to climate change—or some kind of “nuclear winter” devastates the world’s food supplies. Though this might seem far-fetched, it’s not out of the question for our planet. People had to struggle just to get through each day and to feed their families, such that exploration was the furthest from their minds and people started believe that the Apollo program was a hoax. But the drive to explore the unknown and see what’s out there is an inherently human trait. Carl Sagan once wrote, “Exploration is in our nature. We began as wanderers, and we are wanderers still. We have lingered long enough on the shores of the cosmic ocean. We are ready at last to set sail for the stars.” What are other planets, solar systems, or even other galaxies like, and what do their differences tell us about our own? Just today a Scientific American article came out, where the author discusses the thousands of exoplanets observed so far and argues that “Planets More Habitable than Earth may be Common in Our Galaxy.” These are issues we can’t stop thinking about.

One problem is that space is big. “Really big. You just won’t believe how vastly, hugely, mindbogglingly big it is” (to quote the Hitchhiker’s Guide to the Galaxy). Planets that support life are extremely rare, though we don’t know exactly how rare yet. It’s difficult to learn about planets far away, and it won’t be easy to find out which ones humans could visit or which ones might support alien life. Contacting those aliens is more complicated. And then visiting other planets and solar systems, or even setting up colonies on them is literally a multi-generational project. For example, Alpha Centauri is about 4.4 light years away. If astronauts could travel as fast as the Voyager spacecraft…it would take them 77,000 years to get there! They’d wake up from hibernation in their spaceship after all that time, and they wouldn’t even know whether other humans were still alive.

Finally, one of the main points I think we should take away from the movie is that we must take care of our own planet. Earth is rare, and it’s our home. We face many dangers and threats throughout the world, including global warming, drought, floods, famine, air pollution, natural disasters, pandemics, ozone depletion, killer asteroids, and war. We should note that these problems and their effects are related to poverty and inequality too, and that’s not to mention threats to other species on Earth. We might not survive for thousands of years—which is like a blink of an eye for our universe—but we have to try. We have to work together and plan for the future.

On that note, I’ll leave you with the ending of Carl Sagan’s Cosmos:

We are the local embodiment of a Cosmos grown to self-awareness. We have begun to contemplate our origins: starstuff pondering the stars; organized assemblages of ten billion billion billion atoms considering the evolution of atoms; tracing the long journey by which, here at least, consciousness arose. Our loyalties are to the species and the planet. We speak for Earth. Our obligation to survive is owed not just to ourselves but also to that Cosmos, ancient and vast, from which we spring.