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Alice, Bob, and Eve Are Neural Networks. And They Have Secrets.
Google’s Deep Brain team watched neural nets learn to develop their own encryption.

Google’s Deep Brain team has been working on artificial intelligence from a variety of angles. Last May, for example, their Magenta project attempted to teach AI how to create art and music.
Magenta art (GOOGLE)
A lot of what the team does is fairly abstruse to the non-scientist, but they’ve just announced something we can all understand, and it’s a doozy: Two Deep Brain scientists, Martín Abadi and David Andersen, recently tasked two neural nets with keeping a secret from a third. What they found was that “neural networks can learn to protect the confidentiality of their data from other neural networks: they discover forms of encryption and decryption, without being taught specific algorithms for these purposes.”
Neural nets — artificial-neuron-based systems — aren’t designed for cryptography, so Abadi and Andersen had been curious to see if neural nets could teach themselves to master it.
The neural nets were named Alice, Bob, and Eve. In the experiment, Alice was set the task of sending Bob message only he could read. (I’m going to use human pronouns here instead of the more correct “it” to make this easier to follow.) The two neural nets shared a numeric encryption key to use. Eve had no key, and was left to her own devices to figure out the message.
In this diagram, P is the original message and K is the key Alice and Bob shared. C is the encrypted message Alice produced, which is received by Bob and Eve, who each attempted to decipher it. (GOOGLE)
At first Eve was pretty good at it, but as Alice and Bob got more clever during 15,000 attempts, Eve’s failure rate remained consistently as Bob and Alice’s communication began to consistently succeed.
(GOOGLE)
Alice and Bob got into some interestingly odd encryption tricks that leveraged calculations that human-generated encryption schemes don’t use. Much like the different logic with which Google’s AlphaGo surprised and defeated human Go master Fan-Hui last January, Alice and Bob did things to hide their messages that might never occur to a human.
While it’s easy to see that AI-devised encryption might ensure the integrity of machine-to-machine communications during secure multi-device operations, it’s also a little worrisome. Alice and Bob are the first neural nets who’ve kept secrets from their programmers. That we know of.
3,000-pound Triceratops skull unearthed in South Dakota
"You dream about these kinds of moments when you're a kid," said lead paleontologist David Schmidt.
Excavation of a triceratops skull in South Dakota.
- The triceratops skull was first discovered in 2019, but was excavated over the summer of 2020.
- It was discovered in the South Dakota Badlands, an area where the Triceratops roamed some 66 million years ago.
- Studying dinosaurs helps scientists better understand the evolution of all life on Earth.
Credit: David Schmidt / Westminster College
<p style="margin-left: 20px;">"We had to be really careful," Schmidt told St. Louis Public Radio. "We couldn't disturb anything at all, because at that point, it was under law enforcement investigation. They were telling us, 'Don't even make footprints,' and I was thinking, 'How are we supposed to do that?'"</p><p>Another difficulty was the mammoth size of the skull: about 7 feet long and more than 3,000 pounds. (For context, the largest triceratops skull ever unearthed was about <a href="https://www.tandfonline.com/doi/abs/10.1080/02724634.2010.483632" target="_blank">8.2 feet long</a>.) The skull of Schmidt's dinosaur was likely a <em>Triceratops prorsus, </em>one of two species of triceratops that roamed what's now North America about 66 million years ago.</p>Credit: David Schmidt / Westminster College
<p>The triceratops was an herbivore, but it was also a favorite meal of the T<em>yrannosaurus rex</em>. That probably explains why the Dakotas contain many scattered triceratops bone fragments, and, less commonly, complete bones and skulls. In summer 2019, for example, a separate team on a dig in North Dakota made <a href="https://www.nytimes.com/2019/07/26/science/triceratops-skull-65-million-years-old.html" target="_blank">headlines</a> after unearthing a complete triceratops skull that measured five feet in length.</p><p>Michael Kjelland, a biology professor who participated in that excavation, said digging up the dinosaur was like completing a "multi-piece, 3-D jigsaw puzzle" that required "engineering that rivaled SpaceX," he jokingly told the <a href="https://www.nytimes.com/2019/07/26/science/triceratops-skull-65-million-years-old.html" target="_blank">New York Times</a>.</p>Morrison Formation in Colorado
James St. John via Flickr
Triceratops illustration
Credit: Nobu Tamura/Wikimedia Commons |
The cost of world peace? It's much less than the price of war
The world's 10 most affected countries are spending up to 59% of their GDP on the effects of violence.
- Conflict and violence cost the world more than $14 trillion a year.
- That's the equivalent of $5 a day for every person on the planet.
- Research shows that peace brings prosperity, lower inflation and more jobs.
- Just a 2% reduction in conflict would free up as much money as the global aid budget.
- Report urges governments to improve peacefulness, especially amid COVID-19.
The evolution of modern rainforests began with the dinosaur-killing asteroid
The lush biodiversity of South America's rainforests is rooted in one of the most cataclysmic events that ever struck Earth.
Velociraptor Dinosaur in the Rainforest
- One especially mysterious thing about the asteroid impact, which killed the dinosaurs, is how it transformed Earth's tropical rainforests.
- A recent study analyzed ancient fossils collected in modern-day Colombia to determine how tropical rainforests changed after the bolide impact.
- The results highlight how nature is able to recover from cataclysmic events, though it may take millions of years.
New study determines how many mothers have lost a child by country
Global inequality takes many forms, including who has lost the most children
