The blue light from your phone isn’t making you sleep worse, despite what people say. Science proves it. CC-licensed photo by janet isn’t real on Flickr.
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A selection of 10 links for you. Eye-opening. I’m @charlesarthur on Twitter. On Threads: charles_arthur. On Mastodon: https://newsie.social/@charlesarthur. On Bluesky: @charlesarthur.bsky.social. Observations and links welcome.
The blue light from your phone isn’t ruining your sleep • BBC Future
Thomas Germain:
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The public freakout about blue light started with a study in 2014. Half of the 12 participants read on an iPad before bed. The rest read physical books. The iPad users took longer to fall asleep, felt groggier the next day and produced less melatonin. The researchers said the culprit was the glow emitted from the iPad’s LED screen, which produces a disproportionate amount of light in the upper, bluer end of the spectrum. Under specific circumstances, blue-enriched light disrupts the daily circadian rhythm – our body’s natural pacemaker – that uses daylight to help determine when we start to feel tired. Subsequent research seemed to support the findings. Sounds simple, right? It’s not.
“This was an incredibly deceptive piece of work,” says Jamie Zeitzer, a professor of psychiatry and behavioural sciences at Stanford University, who studies the effect of light on the circadian system. The science wasn’t bad, he says, the problem is it brought people to bad conclusions.
It’s true that our screens are bluer. Modern screens and lightbulbs use LEDs, which cannot produce pure white light. Instead, they use blue LEDs and cover some of them with a chemical called yellow phosphor. The blue and yellow mix together and trick your brain into seeing white, but extra blue always leaks out.
And blue light really can influence your sleep. Zeitzer says that’s mostly because you have a light-sensitive protein in your eyes called melanopsin which plays a key role in your sleep system. “And melanopsin is a blue sensitive protein, which basically means that it is most sensitive to blue light,” he says. Melanopsin reacts to other colours of light too, the effect of blue is just a bit stronger.
“But the amount of light emitted from our screens is really inconsequential,” says Zeitzer. Your life doesn’t match the conditions of many blue light studies. “We bring someone into the laboratory, and they are exposed to very dim light all day long. And then they are given a bright light stimulus,” he says. Under those circumstances, blue light makes people go haywire, but it doesn’t reflect typical experience of human life.
After years warnings and millions of people flipping on the blue light filters built into their phones, the latest science suggests screens are not the main culprit here after all. For example, a recent review of 11 different studies and found that the light from screens only delayed sleep by about nine minutes, at worst. Not zero, but not life altering, either.
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A worthwhile piece of journalism. The thing that’s probably making it hard to sleep is what you’re reading on the screen, not the colour of the screen.
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Meta is reentering the AI race with a new model called Muse Spark • The Verge
Hayden Field:
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Meta Superintelligence Labs is launching its first model since Mark Zuckerberg spent billions overhauling the company’s AI efforts. Called Muse Spark, the model now powers the Meta AI app and the Meta AI website in the US, per the company’s announcement. In the coming weeks, Meta says, it will appear in WhatsApp, Instagram, Facebook, Messenger, and Meta’s smart glasses, as well as roll out in other countries.
Like Google Gemini, which easily integrates into Google’s product suite, Meta touts Muse Spark as “purpose-built for Meta’s products.” The model, the first in a new series, will also be available to some of Meta’s partners in private preview” via the API. The company promises the ability to run multiple AI sub-agents to handle queries better and faster, as well as support for multimodal input that includes both text and images. The latter is particularly relevant to Meta’s AI-powered camera glasses, which it’s bet on as the (latest) future of computing. It lets users toggle between a faster “Instant” mode and a “Thinking” mode that’s supposed to deliver more thoroughly reasoned results, similar to options like Microsoft’s Think Deeper.
Meta also highlighted that Muse Spark can answer “complex questions in science, math, and health.” Health-focused AI chatbots have been a controversial topic in recent months, as they handle sensitive personal data and can propagate misinformation. Meta said that Muse Spark’s multimodal perception is “especially valuable for health” and can “navigate health questions with more detailed responses, including some questions involving images and charts.” Meta may be looking to compete with OpenAI’s ChatGPT Health and Anthropic’s Claude for Healthcare, which both debuted in January. In its announcement, it showed its chatbot estimating a calorie count for a meal — a popular, but often hit-or-miss, use of AI tech.
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A new chatbot? Must be a day with a Y in it. Perhaps this is how it felt when the PC revolution first happened and there were scores of new machines from new companies released every year. But software seems to come along dramatically faster.
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Why Anthropic’s new model has cybersecurity experts rattled • Platformer
Casey Newton:
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One of the world’s three frontier labs has now created a model it says is too dangerous to release to the general public. These dangers emerged not from any specialized cyber training but from the same general improvements that every other lab is currently pursuing. As a result, models with similar capabilities may soon be accessible to criminals, hackers, and nation states — or even more broadly via open source models.
Already, Anthropic said, the model has found thousands of high-severity vulnerabilities in every major operating system and web browser, and in many cases developed related exploits. Among them: a vulnerability in OpenBSD, a security-focused open source operating system, that had escaped detection for 27 years; another flaw in the video encoder FFmpeg that had escaped detection in 5 million previous automated tests; and “several” vulnerabilities in the Linux kernel, which could be exploited to take complete control of a user’s machine.
“Given the rate of AI progress, it will not be long before such capabilities proliferate, potentially beyond actors who are committed to deploying them safely,” the company wrote. “The fallout — for economies, public safety, and national security — could be severe. Project Glasswing is an urgent attempt to put these capabilities to work for defensive purposes.”
In a video that Anthropic made to accompany the announcement, researchers say that Mythos is more dangerous largely due to its advanced reasoning capabilities. While current models are capable of identifying high-severity vulnerabilities, Mythos might identify five separate vulnerabilities in a single piece of software and then chain them together into a uniquely dangerous new attack. Coupled with models’ growing ability to work without supervision for extended periods of time, Anthropic said we have reached an inflection point in cybersecurity risks.
…Alex Stamos, chief product officer at cybersecurity firm Corridor, told me that Glasswing is “a big deal, and really necessary.”
“We only have something like six months before the open-weight models catch up to the foundation models in bug finding,” said Stamos, who previously led security at Facebook and Yahoo. “At which point every ransomware actor will be able to find and weaponize bugs without leaving traces for law enforcement to find (and with minimal cost).”
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Stamos is definitely worth listening to. If he says it’s bad, then it’s bad.
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Tankers passing through Strait of Hormuz will have to pay cryptocurrency toll • Financial Times via Ars Technica
Najmeh Bozorgmehr, Alice Hancock, Verity Ratcliffe, and Rachel Millard:
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Iran will demand that shipping companies pay tolls in cryptocurrency for oil tankers passing through the Strait of Hormuz, as it seeks to retain control over passage through the key waterway during the two-week ceasefire.
Hamid Hosseini, a spokesperson for Iran’s Oil, Gas, and Petrochemical Products Exporters’ Union, told the FT on Wednesday that Iran wanted to collect tolling fees from any tanker passing and to assess each ship.
“Iran needs to monitor what goes in and out of the strait to ensure these two weeks aren’t used for transferring weapons,” said Hosseini, whose industry association works closely with the state.
“Everything can pass through, but the procedure will take time for each vessel, and Iran is not in a rush,” he added.
Decisions on the conditions for passing the strait are taken by Iran’s Supreme National Security Council. Hosseini’s remarks suggest Iran will require any tankers to use the northerly route close to its coastline, raising questions over whether Western or Gulf state-linked vessels will be willing to risk transit.
Later on Wednesday Iran said it was halting the passage of oil tankers through the Strait of Hormuz in response to Israeli strikes on Lebanon.
Before the halt Hosseini said that any tanker passing must email authorities about its cargo, after which Iran will inform them of the toll to be paid in digital currencies.
He said that the tariff is $1 per barrel of oil, adding that empty tankers can pass freely.
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Estimates are that this will raise around $70bn annually for Iran, but it won’t have to take the money in dollars: it could trade it with China or Russia, which would be a subtle way to undermine the dollar on world markets.
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Exclusive: ‘Ghost Murmur,’ a never-before used secret tool, deployed to find lost airman in Iran in daring mission • NY Post
Steven Nelson:
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The CIA used a futuristic new tool called “Ghost Murmur” to find and rescue the second American airman who was shot down in southern Iran, The Post has learned.
The secret technology uses long-range quantum magnetometry to find the electromagnetic fingerprint of a human heartbeat and pairs the data with artificial intelligence software to isolate the signature from background noise, two sources close to the breakthrough said.
It was the tool’s first use in the field by the spy agency — and was alluded to Monday afternoon by President Trump and CIA Director John Ratcliffe at a White House briefing.
“It’s like hearing a voice in a stadium, except the stadium is a thousand square miles of desert,” a source briefed on the program told The Post. “In the right conditions, if your heart is beating, we will find you.”
This source and another with knowledge of Lockheed Martin intelligence collection tools told The Post that Ghost Murmur was developed by Skunk Works, the aerospace giant’s secretive advanced development division. The company declined to comment.
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First I had heard of QM, but it does seem to be a thing in navigation and multiple other fields.
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China starts sea trials for largest electric-powered containership • Maritime Executive
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China’s first 10,000-ton electric containership is beginning sea trials. The shipyard is billing the ship as the largest of its kind and a further breakthrough in short-sea shipping.
The Ning Yuan Dian Kun was launched in September 2025 and has completed its outfitting, berth tests, and mooring trials. The ship set out from its builders, Jiangxi Jiangxin Shipbuilding, on February 1. It will be off Shanghai, undergoing its trials between February 6 and 13.
They plan to assess the battery power supply as well as propulsion performance during the sea trials. They will also be testing the ship’s autonomous navigation systems.
The vessel measures nearly 128 meters (420 feet) in length. It has a capacity of 740 TEU [twenty-foot equivalent unit, ie shipping container]. It is reported to have a maximum speed of 11.5 knots.
The power system uses 10 containerized batteries capable of generating up to 19,000 KWh. The batteries will drive two 875 KW permanent magnet propulsion motors, and it will be possible to either recharge the batteries using high-voltage shore connections or quickly swap the batteries for charged batteries. In addition, the vessel has photovoltaic power cells to provide additional power.
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740TEU makes this ship a “small feeder” for “regional routes and smaller ports”. Properly big ships are anything from 5,000 to 24,000TEUs.
Even so, this is ambitious and interesting.
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British computer scientist denies he is bitcoin developer Satoshi Nakamoto • The Guardian
Aisha Down:
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A British computer scientist has insisted he is not the elusive developer of bitcoin, after a report claimed to unmask him as its creator.
A story in the New York Times details a years-long effort to unmask Satoshi Nakamoto, the mysterious author of the bitcoin white paper which laid the theoretical foundations for modern digital currencies.
It names Adam Back, a London-born computer scientist and entrepreneur. In a thread on X, Back promptly denied being the mysterious – and presumably ultra-wealthy – technologist.
“I also don’t know who satoshi is, and i think it is good for bitcoin that this is the case, as it helps bitcoin be viewed [as] a new asset class, the mathematically scarce digital commodity,” he wrote.
Nakamoto’s true identity has been the subject of speculation for years. Previous attempts to unmask him have pointed to Nick Szabo, a “reclusive” Hungarian-American computer scientist; Hal Finney, a software developer; and an “unknown Australian genius” who ended up being a fraud.
This time, the trail pointed the journalist to Back, who was a member of an online anarchist cryptography community called the cypherpunks in the early 1990s.
John Carreyrou unearthed similarities between Back and Nakamoto by combing through decades of old internet postings and analysing commonalities in their public writings – offhand comments such as “I’m better with code than I am with words” – and shared niche interests.
He compared timelines – Back suddenly went dormant for some years on cryptography-related forums, when Satoshi emerged as a presence – and used artificial intelligence to compare Back and Satoshi’s use of language
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The fun thing with this story is that people who claim to be Satoshi are demonstrated not to be, and people who are claimed by others to be deny it. The key qualification for being Satoshi is not to want to be identified as Satoshi; the key disqualification is wanting to be. It’s cryptocurrency’s Catch-22.
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New revelations reignite crypto scandal involving Argentina’s President Milei • The New York Times
Daniel Politi and Emma Bubola:
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President Javier Milei of Argentina promoted a cryptocurrency last year that quickly skyrocketed in value then cratered just as fast, costing investors millions of dollars and setting off a scandal and an investigation.
Mr. Milei said he was simply highlighting a private venture and had no connection to the digital coin called $Libra.
New evidence is now raising questions about his assertion.
Phone logs from a federal investigation by Argentine prosecutors into the coin’s collapse show seven phone calls between Mr. Milei and one of the entrepreneurs behind the cryptocurrency on the night in 2025 when Mr. Milei posted about $Libra on X. The contents of the calls, which took place before and after Mr. Milei’s post, are not known.
But the phone logs — which were obtained by The New York Times and first reported by a local cable news channel, C5N — suggest a greater degree of communication between Mr. Milei and the entrepreneurs who launched the token than what the president has publicly acknowledged. Newly uncovered messages also suggest Mr. Milei received regular payments from one of the entrepreneurs while he was a congressman.
Mr. Milei has not publicly commented on the call logs and other documents, and he did not respond to a request for comment. He is named as a person of interest in the federal prosecutor’s continuing investigation into the digital coin, according to court documents reviewed by The Times, but has not been formally charged with any crime.
The latest revelations have revived a scandal that threatens the very foundation of a president who rose to power and was elected president in 2023 by attacking a political class he called corrupt.
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How surprising. The “value” of the “coin” dropped by $250m from its peak – which means, equally, that $250m ended up in the pockets of a smaller group of people who sold it.
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Genetic predictors of GLP1 receptor agonist weight loss and side effects • Nature
Adam Auton et al:
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The development of glucagon-like peptide 1 (GLP1) receptor agonists, including semaglutide and tirzepatide, has transformed the clinical management of overweight and obesity. However, substantial inter-person variability exists in both weight loss efficacy and the incidence of side effects. To investigate the genetic basis of this variability, here we conduct a genome-wide association study of self-reported weight loss and treatment-related side effects in 27,885 people following GLP1 receptor agonist therapy.
We identify a missense variant in GLP1R that is associated significantly with increased efficacy of GLP1 medications (P = 2.9 × 10−10), with an additional −0.76 kg of weight loss expected per copy of the effect allele. Furthermore, we identify associations linking variation in both GLP1R and GIPR to GLP1 medication-related nausea or vomiting, with the GIPR association being restricted to people using tirzepatide.
We incorporate these findings into a broader model of GLP1 medication response, and demonstrate the ability to stratify patients by efficacy and side effect risk. These findings provide direct genetic evidence that variation in the drug target genes contributes to inter-person variability in response and lay the foundation for precision medicine approaches in the treatment of obesity.
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In other words: there’s a genetic variation that makes GLP-1 drugs more or less effective. Possibly they’ll give people a cheek swab before they start them on these drugs to figure out dosage in future.
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Salem’s Lot: Gulf War update; the Purge of senior US military officers; a US fossil fuel reliance fever dream • JP Morgan
Michael Cembalest:
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The notion that the US is insulated from market consequences of the Strait of Hormuz being closed is mostly false. While US natural gas prices have actually declined this year, most other hydrocarbon-related fuels and refined product prices have increased materially as shown in the first chart2. In some instances, US price increases are even higher than increases elsewhere in the world, as shown in the second chart. For example: US crude oil, wholesale gasoline, naphtha, shipping fuel and certain petrochemical price increases this year are even higher than price increases in Europe and Asia. And even though the US is a net exporter of jet fuel, US jet fuel prices have risen by around two thirds of international increases.
Bottom line: US fossil fuel independence is not as much of an economic firewall as you might think.
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Never linked to a JP Morgan note before, and this one was written before Tuesday’s short-lived “ceasefire”, but all the points in it remain true, notably if the strait of Hormuz remains closed or subject to tariffs. Sorry, taxes.
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| • Why do social networks drive us a little mad? • Why does angry content seem to dominate what we see? • How much of a role do algorithms play in affecting what we see and do online? • What can we do about it? • Did Facebook have any inkling of what was coming in Myanmar in 2016? Read Social Warming, my latest book, and find answers – and more. |
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