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Greg Egan @gregegansf.bsky.social · 1d

MacOS helpfully offers translations:

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Greg Egan @gregegansf.bsky.social · 1d

I get the greatest share (about 70%) if you buy one of my self-published ebooks.

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Greg Egan @gregegansf.bsky.social · 2d

Just received author’s copies of this translation of “The Clockwork Rocket” [Book One of the Orthogonal Trilogy] from Explorer Books, a Russian-language publisher in the Netherlands.

Explorer Books: explorerbooks.org/product/cloc...

About the Orthogonal Trilogy:
www.gregegan.net/ORTHOGONAL/O...

Photo of front cover and spine of Russian translation of “The Clockwork Rocket”, showing a rocket engine firing against a backdrop of colour-trails of stars.

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Greg Egan @gregegansf.bsky.social · 2d

An astonishing result, beautifully described in @quantamagazine.bsky.social: the mathematics linking scattering amplitudes in particle physics to a geometric object called the amplituhedron can be better understood by also mapping the amplituhedron to the mathematics of origami.

Origami Patterns Solve a Major Physics Riddle | Quanta Magazine

The amplituhedron, a shape at the heart of particle physics, appears to be deeply connected to the mathematics of paper folding.

www.quantamagazine.org

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Reposted by Greg Egan

clserdaigle.bsky.social @clserdaigle.bsky.social · 2d

I subscribed to clarkesworld last month and just read this, and as a middle school teacher at an urban public school for very motivated kids, I loved it

Greg Egan @gregegansf.bsky.social · 7d

In a future where the rich kids are being raised with a digital Cyrano beside them to sweet-talk their way into the best jobs, four friends train together for a battle to prove that other kinds of minds might still have the edge.

My new story “Understudies” in Clarkesworld.

Understudies by Greg Egan

Clarkesworld Science Fiction and Fantasy Magazine and Podcast.

clarkesworldmagazine.com

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Greg Egan @gregegansf.bsky.social · 2d

Cringing listening to Avi Loeb on Australian Radio National. The journalist tried valiantly to push back as Loeb compared himself to Galileo and dismissed every expert in comets and planetary science as deluded, but I wish they’d had someone qualified to debate him in real time.

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Greg Egan @gregegansf.bsky.social · 3d

“Flow” was eerily beautiful, charming, sad, strange and hopeful.

Part of my brain baulked at the disparity between the lush, near-photorealistic landscapes and architecture versus the blocky palette in which the animals were rendered, but in the end I managed to shut that out and go with the story.

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Greg Egan @gregegansf.bsky.social · 3d

This is a good account of what intelligent technical people with years of expertise on precisely this question do, and do not, understand about how LLMs work.

www.quantamagazine.org/to-understan...

To Understand AI, Watch How It Evolves | Quanta Magazine

Naomi Saphra thinks that most research into language models focuses too much on the finished product. She’s mining the history of their training for insights into why these systems work the way they d...

www.quantamagazine.org

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Reposted by Greg Egan

Greg Egan @gregegansf.bsky.social · 7d

In a future where the rich kids are being raised with a digital Cyrano beside them to sweet-talk their way into the best jobs, four friends train together for a battle to prove that other kinds of minds might still have the edge.

My new story “Understudies” in Clarkesworld.

Understudies by Greg Egan

Clarkesworld Science Fiction and Fantasy Magazine and Podcast.

clarkesworldmagazine.com

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Greg Egan @gregegansf.bsky.social · 3d

Whew, some good news for a change!

Just spoke to an Afghani friend (in Australia) who said the internet is back across Afghanistan since Wednesday, and incoming flights resumed just in time for some medication he’d sent to a relative to reach her before the last of the previous batch ran out.

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Reposted by Greg Egan

Dr. Jessie Christiansen @aussiastronomer.bsky.social · 6d

This week (!) is the 30th anniversary of the announcement of 51 Pegasi b, the first exoplanet found orbiting a star like our Sun - since then, we've found over 6,000!

To celebrate, @alexwitze.bsky.social and @nature.com collected some astronomers' favourite planets:

www.nature.com/articles/d41...

These alien planets are astronomers’ favourites: here’s why

Space scientists look back on 30 years of exoplanet discoveries — from rows of massive ‘super-Earths‘ to worlds with perfectly synchronized orbits.

www.nature.com

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Greg Egan @gregegansf.bsky.social · 7d

If you like this story — or any of the other stories in Clarkesworld — please think about subscribing if you can. Clarkesworld pay their contributors and staff for their work, and money doesn’t fall from the sky.

clarkesworldmagazine.com

Issue 229

Clarkesworld Science Fiction and Fantasy Magazine and Podcast.

clarkesworldmagazine.com

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Greg Egan @gregegansf.bsky.social · 7d

In a future where the rich kids are being raised with a digital Cyrano beside them to sweet-talk their way into the best jobs, four friends train together for a battle to prove that other kinds of minds might still have the edge.

My new story “Understudies” in Clarkesworld.

Understudies by Greg Egan

Clarkesworld Science Fiction and Fantasy Magazine and Podcast.

clarkesworldmagazine.com

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Greg Egan @gregegansf.bsky.social · 8d

I haven’t had to actually think about PC video connections for 20 years, so when my mother’s monitor started complaining there was “no VGA cable”, I spent 15 minutes checking, plugging and unplugging the (DVI) cable before realising the VGA input had been selected by mistake.

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Reposted by Greg Egan

Corey S. Powell @coreyspowell.bsky.social · 8d

Meteorites striking the Moon release enough energy that we can see the flashes from Earth. The NELIOTA project has witnessed 193 of them (mapped here), creating a novel catalog of impact threats.

A new upgrade means we'll soon see a lot more. 🧪🔭

www.esa.int/Space_Safety...

This map reveals locations of lunar impact flashes detected by the NELIOTA project since 2017.

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Greg Egan @gregegansf.bsky.social · 9d

2025: Hoorah, this *looks* perfect! The chatbots will do all the calculus for us!

2030: Wait ... why did that bridge fall down?

A change of variable on an integral from θ to u = sin θ, du = cos θ dθ. The original integral has a cos θ dθ in the numerator, which is correctly changed to du, but as well as substituting u for sin θ elsewhere in the integral, a factor of 1/√(1-u^2) is introduced, effectively dividing the integrand by cos θ for no reason.

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Greg Egan @gregegansf.bsky.social · 9d

“The Rocky Horror Picture Show” premiered 50 years ago (in August in the UK, September in the US).

Dammit, Janet, that makes me feel old, even though I didn’t see it until 1979, when it was already a cult movie with midnight screenings.

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Greg Egan @gregegansf.bsky.social · 12d

Breaking: Meta are working on a new ML-trained neural implant that will induce the constant belief that you just watched a quite amusing video five seconds ago — even though you can’t recall anything about it — and if you scroll down on your phone you’ll see an even better one!

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Greg Egan @gregegansf.bsky.social · 12d

There are some expressions whose asymptotic scaling for R >> M I can guess at a glance.

This was not one of them!

$Mathematica input: Assuming[R > 0 && M > 0 && 2 M < R, FullSimplify[ Series[ Sqrt[2] R ArcTan[(Sqrt[R] - Sqrt[R - 2 M])/Sqrt[2 M]] - Sqrt[M (R - 2 M)], {M, 0, 2}]]] Output: (4*M^(3/2))/(3*Sqrt[R]) + O(M)^(5/2)$

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Greg Egan @gregegansf.bsky.social · 16d

Breaking: New FDA panel appointed by RFK Jr finds predominant cause of crime is ice cream consumption. “The signal each summer is very strong: ice cream sales go up, violence follows.”

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Reposted by Greg Egan

Philip Ball @philipcball.bsky.social · 16d

Just watched the Tylenol press conference because I had to. It's hard to convey how utterly deranged, even by Trump standards, it was.

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Reposted by Greg Egan

Timothy Gowers @wtgowers.bsky.social · 16d

Our project is to create a database of what we call "structured motivated proofs". For more details about this, and for information about how you can get involved (if you have suitable skills), see a blog post I have just written.

gowers.wordpress.com/2025/09/22/c...

Creating a database of motivated proofs

It’s been over three years since my last post on this blog and I have sometimes been asked, understandably, whether the project I announced in my previous post was actually happening. The ans…

gowers.wordpress.com

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Reposted by Greg Egan

Leo C. Stein @duetosymmetry.com · 16d

I didn't ask for AI in my search. This is really not convincing me!

A screenshot of a google search for "textbooks on superspace", with the AI response:

Key textbooks on superspace include S. James Gates Jr.s Superspace: One Thousand and One Lessons in Supersymmetry, which is available as a free PDF online, and the textbook **M. S. M. M. M. M. M. S. C. S. C. S. G. S. C. S. M. S. T. T. T. S. S. S. S. T. S.S. S. S. S. S. S. G. G. M. M. T. T. R. R. R. R. R. D. S. C. S. R. S. R. M. T. T. G. M. M. S. R. R. G. G. G. G. T. D. S. S. S. S. S. G. G. M. T. S. R. R. R. G. S. S. G. S. R. R. R. M. M. S. T. S. S. S. R. M. R. D. D. T. T. G. G. M. M. S. S. R. R. G. D. S. G. S. R. R. S. D. G. G. M. R. S. D. S. S. R. G. G. M. G. S. G. G. S. R. R. M. S. D. D. R. R. R. G. S. D. D. S. S. R. G. D. S. S. S. R. R. S. S. R. S. C. M. T. G. M. M. G. G. M. D. M. D. G. M. M. G. S. S. G. M M. S. S. S. M. D. M. R. S. S. R. M. S. C. G. R. S. S. D. R. S. R. S. D. G. S. S. R. M. T. G. S. R. S. M. M. G. G. G. S. M. T. T. T. T. G. G. G. S. S. R. D. D. G. D. D. G. M. R. T. S. G. G. D. D. G. D. G. G. M. R. S. S. S. S. M. S. T. D. D. M. S. T. M. D. G. S. R. S. M. S. S. M S. R. G. S. S. R. M. S. S. D. T. R. G. S. D. M. T. T. R. D. S. S. S. D. G. M. M. G. S. T. T. R. R. D. G. M. M. S. D. M. R. R. G. D. S. S. R. R. D. T. S. S. R. G. D. M. S. T. R. R. R. G. M. M. D. D. D. S. S. S. M. R. G. S. R. G. D. M. T. M. D. S. S. S. M. R. M. S. M. D. S. D. S. S. M. S. G. S. R. D. G. M. S. M. S. D. S. G. R. R. D. S. M. R. S. G. G. S. M. M. S. D. D. M. S. G. D. R. G. M. S. M. R. G. R. R. D. G. S. G. M. M. T. S. D. S. G. G. D. R. M. S. M. T. S. R. G. M. S. R. D. S. G. M. D. D. S. G. D. D. G. S. D. D. M. M. T. S. R. D. S. G. G. S. T. G. M. M. M. S. M. S. M. M. S. D. D. S. R. R. M. M. G. G. M. R. S. M. M. S. D. D. М.

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Reposted by Greg Egan

Neuroskeptic @neuroskeptic.bsky.social · 16d

Grid cells are "more like a hash function than a global map or metric" www.biorxiv.org/content/10.1... Grid cell representation is ideally set up to decorrelate and assign easily distinguishable labels to inputs

Not a global map, but a local hash: grid cells decorrelate the representation of position and scramble long-range distance information

Grid cells in the medial entorhinal cortex construct an intriguing multiperiodic representation of space whose properties have been the subject of much theoretical speculation. Here we combine modelin...

www.biorxiv.org

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Reposted by Greg Egan

Rodney Brooks @rodneyabrooks.bsky.social · 18d

In 2011 I wrote a review of Alan Turing's 1948 paper Intelligent Machinery where he considered the case for embodied intelligence. My review was intended for a 2012 centenary celebration of Turing's birth, but no proceedings were published. So here it is. rodneybrooks.com/alan-turing-...

Alan Turing on Embodied Intelligence – Rodney Brooks

rodneybrooks.com

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