Arseny Khakhalin
@khakhalin.bsky.social
Data Scientist in Berlin
Former Bard College prof
For my after-work alter-ego, see @elstersen.bsky.social
Support Ukraine! 🇺🇦
Former Bard College prof
For my after-work alter-ego, see @elstersen.bsky.social
Support Ukraine! 🇺🇦
Pinned
Arseny Khakhalin
@khakhalin.bsky.social
· Apr 14
Minimalistic bifurcation :)
import matplotlib.pyplot as plt
f = lambda x,k,a: (x if k==0 else f(a*x*(1-x), k-1, a))
y = [f(.21, 17 + i % 19, 2.5+1.5*i/10000) for i in range(10000)]
plt.plot(y,'.',markersize=1);
import matplotlib.pyplot as plt
f = lambda x,k,a: (x if k==0 else f(a*x*(1-x), k-1, a))
y = [f(.21, 17 + i % 19, 2.5+1.5*i/10000) for i in range(10000)]
plt.plot(y,'.',markersize=1);
Reposted by Arseny Khakhalin
I wrote a simple guide for getting started with Neo4j Graph Database exploration. We explore a Knowledge Graph of 30 years of Artificial Life research references! Please read and learn along with me! This is useful in Data Science and AI Engineering.🧪
100daysofnetworks.substack.com/p/day-52-of-...
100daysofnetworks.substack.com/p/day-52-of-...
Day 52 of #100daysofnetworks
Cypher Queries: Getting Started with Neo4j Queries
100daysofnetworks.substack.com
November 9, 2025 at 9:58 PM
I wrote a simple guide for getting started with Neo4j Graph Database exploration. We explore a Knowledge Graph of 30 years of Artificial Life research references! Please read and learn along with me! This is useful in Data Science and AI Engineering.🧪
100daysofnetworks.substack.com/p/day-52-of-...
100daysofnetworks.substack.com/p/day-52-of-...
Reposted by Arseny Khakhalin
A minimal map of the world's population for day 11 of the #30DayMapChallenge!
#RStats #ggplot2 #DataViz
#RStats #ggplot2 #DataViz
November 11, 2025 at 10:02 AM
A minimal map of the world's population for day 11 of the #30DayMapChallenge!
#RStats #ggplot2 #DataViz
#RStats #ggplot2 #DataViz
German Nazi party is trying to forbid school teachers from condemning Nazism, calling it "unacceptable political indoctrination". Which formally makes sense, as Nazis are an official party in the parliament, and schools need to stay neutral. Thats the sort of paradoxes you get if you tolerate Nazis.
November 11, 2025 at 10:12 AM
German Nazi party is trying to forbid school teachers from condemning Nazism, calling it "unacceptable political indoctrination". Which formally makes sense, as Nazis are an official party in the parliament, and schools need to stay neutral. Thats the sort of paradoxes you get if you tolerate Nazis.
Reposted by Arseny Khakhalin
November 10, 2025 at 8:21 PM
Reposted by Arseny Khakhalin
80 layers — for those not paying attention, @dorialexander.bsky.social has been posting for weeks about how small models with deep rather than wide layers exhibit eerie emergent behavior
this one is worth checking out
this one is worth checking out
Synthetic playgrounds enabled a series of controlled experiments that brought us to favor extreme depth design. We selected a 80-layers architecture for Baguettotron, with improvements across the board on memorization of logical reasoning: huggingface.co/PleIAs/Bague...
November 11, 2025 at 2:26 AM
80 layers — for those not paying attention, @dorialexander.bsky.social has been posting for weeks about how small models with deep rather than wide layers exhibit eerie emergent behavior
this one is worth checking out
this one is worth checking out
Reposted by Arseny Khakhalin
Super interesting. For training small LLMs, they get results comparable to those trained on an order of magnitude more tokens by replacing normal pre-training (which ingests huge amounts of human-written text) with exclusively synthetic text derived in a structured way from Wikipedia.
SYNTH is a radical departure from the classic pre-training recipe: what if we trained for reasoning and focused on the assimilation of knowledge and skill that matters? At its core it’s an upsampling of Wikipedia 50,000 “vital” articles. huggingface.co/datasets/Ple...
November 10, 2025 at 9:47 PM
Super interesting. For training small LLMs, they get results comparable to those trained on an order of magnitude more tokens by replacing normal pre-training (which ingests huge amounts of human-written text) with exclusively synthetic text derived in a structured way from Wikipedia.
Reposted by Arseny Khakhalin
The protein concentration in the cytoplasm is so high that the average protein has a water hydration shell with a thickness of only ≈ 10 water molecules separating it from the adjacent protein hydration shell.
1/2
1/2
November 10, 2025 at 12:57 PM
The protein concentration in the cytoplasm is so high that the average protein has a water hydration shell with a thickness of only ≈ 10 water molecules separating it from the adjacent protein hydration shell.
1/2
1/2
Reposted by Arseny Khakhalin
An engineer wanted to make a quiet high-speed train. “The question then occurred to me — is there some living thing that manages sudden changes in air resistance as a part of daily life?” The answer: the kingfisher. See my story today for more tales of bioinspiration. Gift link: nyti.ms/4otNQyl
November 10, 2025 at 5:10 PM
An engineer wanted to make a quiet high-speed train. “The question then occurred to me — is there some living thing that manages sudden changes in air resistance as a part of daily life?” The answer: the kingfisher. See my story today for more tales of bioinspiration. Gift link: nyti.ms/4otNQyl
Reposted by Arseny Khakhalin
Smoke Signal is an event & RSVP platform built on ATProto.
@ngerakines.me just dropped a massive upgrade for organizers & attendees - a new design, profiles, rich text, integrated email notifications, private content for attendees, verified RSVPs, and even MCP support.
@ngerakines.me just dropped a massive upgrade for organizers & attendees - a new design, profiles, rich text, integrated email notifications, private content for attendees, verified RSVPs, and even MCP support.
November 10, 2025 at 3:52 PM
Smoke Signal is an event & RSVP platform built on ATProto.
@ngerakines.me just dropped a massive upgrade for organizers & attendees - a new design, profiles, rich text, integrated email notifications, private content for attendees, verified RSVPs, and even MCP support.
@ngerakines.me just dropped a massive upgrade for organizers & attendees - a new design, profiles, rich text, integrated email notifications, private content for attendees, verified RSVPs, and even MCP support.
Reposted by Arseny Khakhalin
*Women receive substantially lower "potential" ratings despite receiving higher performance ratings
*Differences in potential ratings account for half of the gender promotion gap
*Women’s lower potential ratings do not reflect future performance: women subsequently outperform male colleagues
*Differences in potential ratings account for half of the gender promotion gap
*Women’s lower potential ratings do not reflect future performance: women subsequently outperform male colleagues
Forthcoming in the AER: "“Potential” and the Gender Promotion Gap" by Alan Benson, Danielle Li, and Kelly Shue. www.aeaweb.org/articles?id=...
“Potential” and the Gender Promotion Gap
(Forthcoming Article) - We show that subjective assessments of employee “potential” contribute to gender gaps
in promotion and pay. Using data on 29,809 management-track employees from a
large retail ...
www.aeaweb.org
November 10, 2025 at 2:54 PM
*Women receive substantially lower "potential" ratings despite receiving higher performance ratings
*Differences in potential ratings account for half of the gender promotion gap
*Women’s lower potential ratings do not reflect future performance: women subsequently outperform male colleagues
*Differences in potential ratings account for half of the gender promotion gap
*Women’s lower potential ratings do not reflect future performance: women subsequently outperform male colleagues
tldr: it's easy to speak words if they are kinda alike
it's easy to understand them if they are very different
producing a constant and uneasy dynamic balance!
it's easy to understand them if they are very different
producing a constant and uneasy dynamic balance!
⚠️ New paper! Why do words sound so similar? In an agent-based model + communication game, we show that production/comprehension pressures trade off to shape lexicon structure.
In @cognitionjournal.bsky.social w/ @simonkirby.bsky.social & Jenny Culbertson.
www.sciencedirect.com/science/arti...
In @cognitionjournal.bsky.social w/ @simonkirby.bsky.social & Jenny Culbertson.
www.sciencedirect.com/science/arti...
The lexicon adapts to competing communicative pressures: Explaining patterns of word similarity
Cross-linguistically, lexicons tend to be more phonetically clustered than required by the phonotactics of the language; that is, words within a langu…
www.sciencedirect.com
November 10, 2025 at 2:06 PM
tldr: it's easy to speak words if they are kinda alike
it's easy to understand them if they are very different
producing a constant and uneasy dynamic balance!
it's easy to understand them if they are very different
producing a constant and uneasy dynamic balance!
Pretty! Clever! Useful! Ethical! (In the sense that it's also math, but for a change it doesn't give you unemployment, quite the contrary! We need more of that! :)
We figured out flow matching over states that change dimension. With "Branching Flows", the model decides how big things must be! This works wherever flow matching works, with discrete, continuous, and manifold states. We think this will unlock some genuinely new capabilities.
November 10, 2025 at 1:53 PM
Pretty! Clever! Useful! Ethical! (In the sense that it's also math, but for a change it doesn't give you unemployment, quite the contrary! We need more of that! :)
Reposted by Arseny Khakhalin
One of the most self-destructive things Germany could do is to reverse the green transition now.
Renewables expansion has been on a tear but Germany has seen reversals before, unfortunately. And the country still does not have oil or gas and isn’t getting any anytime soon (ever).
Renewables expansion has been on a tear but Germany has seen reversals before, unfortunately. And the country still does not have oil or gas and isn’t getting any anytime soon (ever).
November 9, 2025 at 3:28 PM
One of the most self-destructive things Germany could do is to reverse the green transition now.
Renewables expansion has been on a tear but Germany has seen reversals before, unfortunately. And the country still does not have oil or gas and isn’t getting any anytime soon (ever).
Renewables expansion has been on a tear but Germany has seen reversals before, unfortunately. And the country still does not have oil or gas and isn’t getting any anytime soon (ever).
Reposted by Arseny Khakhalin
A genomic perspective on the origins of different synaptic functions
The evolutionary origins of synaptic proteins and their changing roles in different organisms across evolution — a Review by Jeffrey J. Colgren & Pawel Burkhardt
@jeffcolgren.bsky.social @pawelburkhardt.bsky.social
#neuroscience #neuroskyence
www.nature.com/articles/s41...
@jeffcolgren.bsky.social @pawelburkhardt.bsky.social
#neuroscience #neuroskyence
www.nature.com/articles/s41...
The evolutionary origins of synaptic proteins and their changing roles in different organisms across evolution - Nature Reviews Neuroscience
Recent studies have shed further light on the evolutionary origins of chemical synapses, In this Review, Colgren and Burkhardt explore how ancient proteins were co-opted into functional assemblies and...
www.nature.com
November 10, 2025 at 8:45 AM
A genomic perspective on the origins of different synaptic functions
Reposted by Arseny Khakhalin
Solar’s price drop is astonishing: panels are now 98% cheaper than when I first analyzed them in 2004.
Today, building a fence with solar can be cheaper than using wood.
Today, building a fence with solar can be cheaper than using wood.
November 10, 2025 at 8:10 AM
Solar’s price drop is astonishing: panels are now 98% cheaper than when I first analyzed them in 2004.
Today, building a fence with solar can be cheaper than using wood.
Today, building a fence with solar can be cheaper than using wood.
Gosh that's a very good long read, but not an easy one :)
scottaaronson.blog?p=9030
scottaaronson.blog?p=9030
November 10, 2025 at 8:41 AM
Gosh that's a very good long read, but not an easy one :)
scottaaronson.blog?p=9030
scottaaronson.blog?p=9030
Slopaganda is unfortunately a useful neologism here
As you may know, the US Department of Labor is posting White Christian Nationalist, fascist-style AI #slopaganda for months now. Or, as the Washington Post puts it: «The campaign has drawn scrutiny, with critics saying it is not realistically portraying the diversity of the country’s workforce …»
Labor Department social media campaign depicts a White male workforce
The campaign has drawn scrutiny, with critics saying it is not realistically portraying the country’s diversity and is sending messages that feel exclusionary.
www.washingtonpost.com
November 10, 2025 at 8:00 AM
Slopaganda is unfortunately a useful neologism here
Reposted by Arseny Khakhalin
But instead of crashing, it just stagnated and declined, as whlie being evil is indeed not profitable, it is not suboptimal enough for a quick learning point. We got slow and painful rot, erosion, corruption, counterfactuals and propaganda kicked in, ppl got used to crap, the learning point was lost
November 10, 2025 at 7:57 AM
But instead of crashing, it just stagnated and declined, as whlie being evil is indeed not profitable, it is not suboptimal enough for a quick learning point. We got slow and painful rot, erosion, corruption, counterfactuals and propaganda kicked in, ppl got used to crap, the learning point was lost
Reposted by Arseny Khakhalin
The last decade had quite a few cases, in politics and business, where people did obviously bad (evil) things that were also obviously wrong practically, and you wanted them to crash and fail fast, as this would have signalled to others that being evil is not profitable. Performative goodness sells!
November 10, 2025 at 7:57 AM
The last decade had quite a few cases, in politics and business, where people did obviously bad (evil) things that were also obviously wrong practically, and you wanted them to crash and fail fast, as this would have signalled to others that being evil is not profitable. Performative goodness sells!
Reposted by Arseny Khakhalin
By replying to Elise below, we could generate a nice thread.
Hey complexity and complexity-adjacent people:
What are some of your favorite pop-sci books? Are there any you've had your eye on but haven't had a chance to read yet?
They can be new or old. I'd just love to know what y'all are reading!
What are some of your favorite pop-sci books? Are there any you've had your eye on but haven't had a chance to read yet?
They can be new or old. I'd just love to know what y'all are reading!
November 9, 2025 at 2:37 PM
By replying to Elise below, we could generate a nice thread.
Just had a similar conversion with someone who dropped from a math major after going through a horrible secondary school. They said, I wish I had access to DeepSeek back then, I wouldn't have dropped! Someone you can ask embarrassingly stupid question without fear of being mocked, humiliated!
This is a cool paper showing that first-gen college students don't realize a lot of unwritten rules that lead to success (the value of internships, student clubs, letters from professors).
But giving them access to an LLM for guidance significantly closes the gap. mgcuna.github.io/website/JMP_...
But giving them access to an LLM for guidance significantly closes the gap. mgcuna.github.io/website/JMP_...
November 9, 2025 at 4:22 PM
Just had a similar conversion with someone who dropped from a math major after going through a horrible secondary school. They said, I wish I had access to DeepSeek back then, I wouldn't have dropped! Someone you can ask embarrassingly stupid question without fear of being mocked, humiliated!
The article is paywalled, but the (short) thread is interesting. tldr: it was not _as_ impossible as I thought, just about 100 times too expensive, plus too toxic for the complexity of the task
NEW: The End of the Line: the centrepiece of Saudi Arabia’s Neom gigaproject - a 500m tall, 170km long wall-like building intended ultimately to house 9 million people - can’t get out of the ground, say more than 20 former Neom architects, engineers and senior executives.
ig.ft.com/saudi-neom-l...
ig.ft.com/saudi-neom-l...
End of The Line: how Saudi Arabia’s Neom dream unravelled
Mohammed bin Salman’s utopian city was undone by the laws of physics and finance
ig.ft.com
November 9, 2025 at 11:37 AM
The article is paywalled, but the (short) thread is interesting. tldr: it was not _as_ impossible as I thought, just about 100 times too expensive, plus too toxic for the complexity of the task
Reposted by Arseny Khakhalin
There was some great work done too - to industrialise and standardise the construction process, something that many people across the industry say needs to happen. The just in time construction system they developed was impressive.
November 6, 2025 at 7:00 AM
There was some great work done too - to industrialise and standardise the construction process, something that many people across the industry say needs to happen. The just in time construction system they developed was impressive.
For months now I can't escape dissonance when reading about agentic coding:
Bsky: I only review now, everything automated, go brrr for 6h, new era, "they don't know" meme vibe
Me: some agentic, takes forever to check, is often wrong, painful minimal increments the only way
Colleagues: toxic slop
Bsky: I only review now, everything automated, go brrr for 6h, new era, "they don't know" meme vibe
Me: some agentic, takes forever to check, is often wrong, painful minimal increments the only way
Colleagues: toxic slop
November 9, 2025 at 11:15 AM
For months now I can't escape dissonance when reading about agentic coding:
Bsky: I only review now, everything automated, go brrr for 6h, new era, "they don't know" meme vibe
Me: some agentic, takes forever to check, is often wrong, painful minimal increments the only way
Colleagues: toxic slop
Bsky: I only review now, everything automated, go brrr for 6h, new era, "they don't know" meme vibe
Me: some agentic, takes forever to check, is often wrong, painful minimal increments the only way
Colleagues: toxic slop
The link itself! : itiner-e.org
A high-resolution digital map allows people to plan their routes along the ancient roads of the Roman Empire
go.nature.com/4nHZmoM
go.nature.com/4nHZmoM
‘Google Maps’ for Roman roads reveals vast extent of ancient network
Nature - A high-resolution digital map nearly doubles the known length of the ancient road network.
go.nature.com
November 9, 2025 at 10:41 AM
The link itself! : itiner-e.org