Sean Carroll, fully Sean Michael Carroll

Sean
Carroll, fully Sean Michael Carroll
1966

American Cosmologist and Physics Research Professor in the Department of Physics at the California Institute of Physics, Author

Author Quotes

The reason why science and religion are actually incompatible is that, in the real world, they reach incompatible conclusions. It?s worth noting that this incompatibility is perfectly evident to any fair-minded person who cares to look. Different religions make very different claims, but they typically end up saying things like ?God made the universe in six days? or ?Jesus died and was resurrected? or ?Moses parted the red sea? or ?dead souls are reincarnated in accordance with their karmic burden.? And science says: none of that is true. So there you go, incompatibility.

We are looking for a complete, coherent, and simple understanding of reality. Given what we know about the universe, there seems to be no reason to invoke God as part of this description.

The result is a complete fiasco. Our simple estimate of what the vacuum energy should be comes out to about 10105 joules per cubic centimeter. That?s a lot of vacuum energy. What we actually observe is about 10-15 joules per cubic centimeter. So our estimate is larger than the experimental value by a factor of 10120?a 1 followed by 120 zeroes. Not something we can attribute to experimental error. This has been called the biggest disagreement between theoretical expectation and experimental reality in all of science.

We are part of the universe that has developed a remarkable ability: We can hold an image of the world in our minds. We are matter contemplating itself.

The speed of time is 1 hour per hour, no matter what else is going on in the universe.

We don?t know how the universe began, or if it?s the only universe. We don?t know the ultimate, complete laws of physics. We don?t know how life began, or how consciousness arose. And we certainly haven?t agreed on the best way to live in the world as good human beings.

The strength of the electromagnetic interaction, for example, is fixed by a number called the fine-structure constant, a famous quantity in physics that is numerically close to 1/137.

We find ourselves, not as a central player in the life of the cosmos, but as a tiny epiphenomenon, flourishing for a brief moment as we ride a wave of increasing entropy ? purpose and meaning are not to be found in the laws of nature, or in the plans of any external agent, but in our urges.

The universe is not a miracle. It simply is, unguided and unsustained, manifesting the patterns of nature with scrupulous regularity. Over billions of years it has evolved naturally, from a state of low entropy toward increasing complexity, and it will eventually wind down to a featureless equilibrium. We are the miracle, we human beings. Not a break-the-laws-of-physics kind of miracle? It is wondrous and amazing how such complex, aware, creative, caring creatures could have arisen in perfect accordance with those laws. Our lives are finite, unpredictable, and immeasurably precious. Our emergence has brought meaning and mattering into the world.

We have to be willing to accept uncertainty and incomplete knowledge, and always be ready to update our beliefs as new evidence comes in? Our best approach to describing the universe is not a single, unified story but an interconnected series of models appropriate at different levels. Each model has a domain in which it is applicable, and the ideas that appear as essential parts of each story have every right to be thought of as ?real.? Our task is to assemble an interlocking set of descriptions, based on some fundamental ideas, that fit together to form a stable planet of belief.

The world is not magic ? and that?s the most magical thing about it.

We seek an understanding of the laws of nature and of our particular universe in which everything makes sense to us. We do not want to be reduced to accepting the strange features of our universe as brute facts.

The world is what exists and what happens, but we gain enormous insight by talking about it ? telling its story ? in different ways.

We?re not allowed to call the Higgs Boson the ?God Particle? anymore because now there?s evidence that it exists.

The world keeps happening, in accordance with its rules; it's up to us to make sense of it and give it value.

When society puts some small fraction of its wealth into asking and answering big questions, it reminds us all of the curiosity we have about our universe. And that leads to all sorts of good places.

Then we compare the predicted abundance of such a WIMP with the actual abundance of dark matter.

Wormholes don?t grow on trees.

The key word there is ?useful.? There are certainly non-useful ways of talking about the world. In scientific contexts, we refer to such non-useful ways as ?wrong? or ?false.? A way of talking isn?t just a list of concepts; it will generally include a set of rules for using them, and relationships among them. Every scientific theory is a way of talking about the world.

There are actually three points I try to hit here. The first is that the laws of physics underlying everyday life are completely understood. There is an enormous amount that we don?t know about how the world works, but we actually do know the basic rules underlying atoms and their interactions ? enough to rule out telekinesis, life after death, and so on. The second point is that those laws are dysteleological ? they describe a universe without intrinsic meaning or purpose, just one that moves from moment to moment. The third point ? the important one, and the most subtle ? is that the absence of meaning ?out there in the universe? does not mean that people can?t live meaningful lives. Far from it. It simply means that whatever meaning our lives might have must be created by us, not given to us by the natural or supernatural world. There is one world that exists, but many ways to talk about; many stories we can imagine telling about that world and our place within it, without succumbing to the temptation to ignore the laws of nature. That?s the hard part of living life in a natural world, and we need to summon the courage to face up to the challenge.

The most difficult problem is a philosophical one: how is it even possible that inner experience, the uniquely experiential aboutness of our lives inside our heads, can be reduced to mere matter in motion? Poetic naturalism suggests that we should think of ?inner experiences? as part of a way of talking about what is happening in our brains. But ways of talking can be very real, even when it comes to our ability to make free choices as rational beings.

There is a famous joke, attributed to Einstein: When a man sits with a pretty girl for an hour, it seems like a minute. But let him sit on a hot stove for a minute and it?s longer than any hour. That?s relativity. I don?t know whether Einstein actually ever said those words. But I do know that?s not relativity.

The most famous story about gravity involves Isaac Newton and an apple that supposedly fell on his head, inspiring him to concoct his theory of universal gravitation. (It?s mostly famous because Newton himself couldn?t stop telling it later in life, in an unnecessary attempt to add some extra juice to his reputation as a genius.)

They then build detectors that patiently wait for the faint signal of a dark-matter particle passing through and perturbing a nucleus.

The neutron is a bit of a drama queen.

Author Picture
First Name
Sean
Last Name
Carroll, fully Sean Michael Carroll
Birth Date
1966
Bio

American Cosmologist and Physics Research Professor in the Department of Physics at the California Institute of Physics, Author