Sean Carroll's avatar

Sean Carroll

@seanmcarroll.bsky.social

6176 followers 251 following 721 posts

Physics, philosophy, complexity. Johns Hopkins & Santa Fe Institute. Host, #MindscapePodcast. Married to @jenlucpiquant.bsky.social.
In May: Quanta & Fields, book 2 of The Biggest Ideas in the Universe.
preposterousuniverse.com/

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Paradigm shift: I now think LLMs will make better PhD advisors than most humans.

3 replies 2 reposts 32 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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The Ars Technica time travel discussion was one of the most fun panels I've ever been on.

www.youtube.com/live/PNUSUZr...

1 replies 2 reposts 21 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Wow this is true! As far as I can tell, all from the days when our blog Cosmic Variance was hosted by Discover magazine, so apparently that's a favorite source of examples for this particular Merriam-Webster online dictionary.

3 replies 0 reposts 8 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Mindscape Ask Me Anything | July 2024. We talk about transporter machines, what tensor really are, declining democracy, and how cats adjust to new homes. #MindscapePodcast
www.preposterousuniverse.com/podcast/2024...

1 replies 1 reposts 20 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Disturbed to look up "construal" in the online dictionary (to verify I was using it correctly), and find that the example given was a sentence by me. Don't other people use this wonderful word?

www.merriam-webster.com/dictionary/c...

16 replies 1 reposts 46 likes

Reposted by Sean Carroll

Katie Mack's avatar Katie Mack @astrokatie.com
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The first episode of my new video series, Cosmology 101, is out now! This one is about cosmic expansion. Check it out and subscribe to the Perimeter Institute’s YouTube channel to get the whole series! youtu.be/7GC8XOKwRpM?... #Cosmology101

38 replies 191 reposts 562 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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So many worthwhile acts fall a bit short of being revolutionary!

1 replies 0 reposts 3 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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British politics can be confusing for outsiders, but at least we get updates on Larry the Cat, official mouser of 10 Downing St.

2 replies 1 reposts 34 likes

Reposted by Sean Carroll

Moira Donegan's avatar Moira Donegan @moiradonegan.bsky.social
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Not to be corny but I do think the ongoing aspiration to make America a pluralist democracy of equals is righteous, beautiful, and worth honoring, even if it has more often been the struggle of minorities & dissenters than the policy of the government. 🇺🇸

22 replies 355 reposts 1662 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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I’ve never had the pleasure of meeting @harthanson.bsky.social in person, but I did have a great time briefly serving as a science consultant on BONES. Now I’m reading The Seminarian, and it’s so much fun. Recommended for anyone who loves rompy mystery novels. E.g.:

2 replies 0 reposts 14 likes

Reposted by Sean Carroll

Radley Balko's avatar Radley Balko @radleybalko.bsky.social
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Not that anyone is asking me, but I have no idea what the Democrats should do right now. All the options seem bad, and there isn’t one that seems less bad than the others. And as a professional opinion-haver, it’s disorienting to have no strong opinion about something so enormously consequential.

64 replies 48 reposts 699 likes

Reposted by Sean Carroll

c0nc0rdance's avatar c0nc0rdance @c0nc0rdance.bsky.social
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Something that always amazes me: When you turn on the tap in your home, you're draining the water out of a giant tower, by gravity. From the point of view of the water, it must be a wild ride.

5 replies 6 reposts 41 likes

Reposted by Sean Carroll

Kevin M. Kruse's avatar Kevin M. Kruse @kevinmkruse.bsky.social
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The States Project is one of the best bang-for-your-buck options for your campaign donations. Even beyond it, though, state legislatures deserve your attention. Next time you're tempted to send money to whoever's going to lose to MTG, send it instead to a contested state leg seat.

18 replies 265 reposts 656 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Ariel has been frustrated by the slippery nature of mathematical truth, and has decided to take it out on Kurt Gödel.

3 replies 3 reposts 40 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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The find-the-keys scene in Bill & Ted is the most perfectly executed time-travel gimmick in cinema. Hear us chat about it and all the others.

1 replies 3 reposts 18 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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SCOTUS rulings aren't as visceral as debate performances or even felony trials, so I suspect a lot of people are undercounting the impact of this last week. Democracy dies, not in darkness, but right there under the bright lights for everyone to see.

3 replies 13 reposts 55 likes

Reposted by Sean Carroll

Reposted by Sean Carroll

Radley Balko's avatar Radley Balko @radleybalko.bsky.social
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My first read: If a president commits crimes unrelated to him being the most powerful person in the world, he can be prosecuted. But if explicitly uses his powers to commit crimes, he is at least presumptively, and probably absolutely immune from prosecution. I mean, holy shit.

28 replies 220 reposts 947 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Now I'm depressed about politics again. But I had a good 12 hours where basketball was keeping me joyful.

2 replies 1 reposts 18 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Nope. Gotta take the gamble for an all star who is a perfect fit with Embiid and Maxey.

1 replies 0 reposts 1 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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I may be a fundamentally frivolous person, but can't let politics get me down when the Sixers are dominating the offseason so thoroughly. Can't wait for the season to start!

2 replies 0 reposts 5 likes

Reposted by Sean Carroll

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Since Trump is a convicted felon and spent the whole debate fabricating falsehoods and is an autocratic insurrectionist, it’s time to think about who the Republican convention should replace him with once he’s forced to withdraw. Romney, maybe?

8 replies 15 reposts 109 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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It’s not really testing psychology, of course.

1 replies 0 reposts 1 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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This is why the ARC challenge won’t reveal the problems publicly, if I understand correctly. And LLMs do much worse on it than humans.

arcprize.org

3 replies 2 reposts 5 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Bonus interloper. Never know what you’ll encounter on the mean streets of central Baltimore.

1 replies 0 reposts 25 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Good: in that mode where you're so engrossed in the paper you're writing that you dream about it all night. Bad: waking self not nearly as clever as dream self.

7 replies 1 reposts 48 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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I was surprised at first, because thermodynamically, the brain is incredibly efficient- it produces much less waste heat per computation than a computer. But if you’re talking chemicals, then sure.

3 replies 5 reposts 17 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Being poor is a trap that is very hard to escape, and giving people a bit of money can make all the difference.

4 replies 9 reposts 64 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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And the real problem with the PSR has (basically) nothing to do with randomness from quantum mechanics. It's just that attaching unique "reasons" to events isn't how fundamental physics really works.

3 replies 0 reposts 8 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Originally wrote "or so I argue...", but honestly this is a fairly casual examination rather than a careful argument, so caveat lector.

1 replies 0 reposts 6 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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The Principle of Sufficient Reason says that there is a reason for everything that happens. Does physics somehow provide support for this idea? Not really! Or so I suggest in this short paper.

philarchive.org/rec/CARPAT-30

3 replies 3 reposts 20 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Democritus stretching through time to look over my shoulder and ask whether I really need another book on information theory instead of reading the ones I have.

5 replies 0 reposts 30 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Nope. Just means we have some science to do, as usual.

1 replies 0 reposts 1 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Nothing very profound to conclude, just some thoughts I scribbled down for a great workshop on the philosophy of thermodynamics organized by @wmyrvold.bsky.social this week.

It would be great to better understand how Nature actually does search through the space of complex systems!

6 replies 1 reposts 20 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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So for strands longer than 181 base pairs, there is not enough time or matter in the universe to search through all the possibilities. And the human genome has 3 billion. So the search that Nature has actually done is very sparse indeed.

4 replies 0 reposts 13 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Since it's a thought experiment, imagine that each strand runs through possible combinations at a billion per second, searching for the fittest one. (Not realistic!) In that case, the whole universe can search all of the genomes of length N as large as ... 181.

2 replies 0 reposts 13 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Thought experiment: take all of the protons & neutrons in the observable universe, put them in the form of DNA nucleotides, collected into strands of length N. Then imagine the universe searches through all possible combinations. How many can be searched in the age of the universe?

1 replies 0 reposts 12 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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One thing about complex systems is: the space of possibilities is mind-bogglingly large. Consider DNA. The human genome has about 3 billion base pairs. How well has evolution searched through all the possible genomes to find the fittest ones? Not very well at all. 🧵

8 replies 6 reposts 48 likes

Sean Carroll's avatar Sean Carroll @seanmcarroll.bsky.social
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Basically the plot of Marvel’s Civil War!

0 replies 0 reposts 1 likes