Catboy physicist 🏳️‍🌈🧶⚛️ (@stringlandscape) header
Catboy physicist 🏳️‍🌈🧶⚛️ (@stringlandscape) profile picture

物理学猫耳 Correction: An earlier version of this bio misidentified catboy physicist as an economist. We regret the error. 🔪🌻, 🐙🦀

Who can say?
Joined September 2011
Photo by Catboy physicist 🏳️‍🌈🧶⚛️ (@stringlandscape)Photo by Catboy physicist 🏳️‍🌈🧶⚛️ (@stringlandscape)Photo by Catboy physicist 🏳️‍🌈🧶⚛️ (@stringlandscape)Photo by Catboy physicist 🏳️‍🌈🧶⚛️ (@stringlandscape)Photo by Catboy physicist 🏳️‍🌈🧶⚛️ (@stringlandscape)Photo by Catboy physicist 🏳️‍🌈🧶⚛️ (@stringlandscape)Photo by Catboy physicist 🏳️‍🌈🧶⚛️ (@stringlandscape)Photo by Catboy physicist 🏳️‍🌈🧶⚛️ (@stringlandscape)Photo by Catboy physicist 🏳️‍🌈🧶⚛️ (@stringlandscape)Photo by Catboy physicist 🏳️‍🌈🧶⚛️ (@stringlandscape)
Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
Pessimistic but worth reading. What I think it gets right is that willingness to actually DO the things that give life meaning—thinking, art, spending time with friends—is responsive to incentives, and for most people requires some institutional support. (Yes, even spending time with friends; compare how much you do so now as opposed to during high school or college.) Where I’m more optimistic is that I think the institutions that allow this will plausibly survive and flourish, and perhaps even increase in importance.
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
Restrictions on porn are genuinely such an insidious trojan horse for mass censorship because if you try to speak out against it, people on both sides of the political aisle will just write you off as a pervert.
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
claude now refuses to recreate specific existing games. Anthropic says users can't turn it off, and it covers clones, ports and mods. gamedevs doing licensed work are already complaining. this is a big deal for modders who make mashups or rebuild source. gameranx.com/updates/id/5644…
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
Obviously lots of porn being made technically illegal doesn't necessarily mean the cops will be battering down your door at every little offence. But that just means they have broad discretion to selectively enforce it against people they dislike.
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
This is actually a lot more drastic than the age checks, as the banned categories are a criminal offence for you personally, rather than a regulation on websites. And if you get caught, the charge will just be “extreme pornography” so everyone will assume you’re a Proper Nonce.
Them banning different types of porn in the UK is so funny because to look at porn in the UK everyone is using a VPN nowerdays so it does nothing
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
In the UK, you can now feasably receive a 5 year prison sentence if you record yourself having oral sex while possessing too large of a penis.
I was consulted by the US Free Speech Coalition (@FSCArmy) to advise on this UK “Choking” Content Ban FAQ for Platforms and Creators This FAQ contains general information to help you understand the UK’s new choking content ban, not legal advice. It summarizes what the law, the government’s guidance, and other official sources say about the UK’s new ban on choking content, as of October 2026. Every business and every piece of content is different, so please talk to a UK lawyer about your situation. The basics Who does the law apply to? Anyone who possesses or publishes choking content in the UK. The law says it is illegal to possess or publish it. There’s no exception based on who you are or why you have the content.* FSC cannot give legal advice (especially on such a vague law), but our impression is that individuals and companies located in the UK that create or publish choking content are at highest risk. Companies not located in the UK that block UK users altogether, or otherwise prevent UK users from accessing content prohibited under UK law would likely face lower risk, but we cannot stress enough how important it is to talk to a UK lawyer about your specific content before November 6. * If you are prosecuted, you may be able to argue in court that you had a legitimate reason for possessing or publishing it. Is choking content banned in the UK? Depicting "in an explicit and realistic way, a person strangling or suffocating another person" in the UK is now a crime. Neither strangulation nor suffocation are defined in the law. The government says the words will be given their "ordinary meaning" and whether an image depicts strangulation or suffocation "will be a question of fact for the court in each case." What are the potential criminal penalties? Publication can lead to up to 5 years' imprisonment. The maximum for possession is 2 years' imprisonment. Fines are also possible. Prosecutions need the consent of the Director of Public Prosecutions. Will Ofcom enforce this law? The new law makes possession or publication of choking content a priority offense under the Online Safety Act. Ofcom says it "will provide an update to our policy roadmap by the end of the year" regarding "new offences that make certain types of pornography content illegal." We anticipate this will involve a public consultation and lengthy drafting process. What counts as choking? What could "strangulation" mean? According to the government: "We consider that strangulation generally means one person applying pressure to another person's neck." The Crown Prosecution Service (CPS) guidance on prosecuting the offense of strangulation that suggests defining it as "the application of force or pressure by the defendant to the victim’s neck, whether using their hands or other means" and "does not require a particular level of pressure or force within its ordinary meaning, it does not require any injuryand it does not require...impeded breathing or circulation." They offer these examples of what could constitute strangulation: one or two hands held around the neck of a person, chokeholds or head locks, ligatures such as a scarf or belt tightened around the neck, pressure on the neck from a foot or knee. Whether an image depicts strangulation or suffocation "will be a question of fact for the court in each case." What could "suffocation" mean? According to the government: "We consider that suffocation will generally mean depriving a person of air in a way that affects their ability to breathe. Unlike strangulation, this does not require pressure to the neck. It could, for example, involve covering someone's mouth and nose or compressing their chest." The CPS guidance on prosecuting the offense of strangulation that suggests this definition: "to deprive a person of air which affects their normal breathing" and notes that "any action that causes a person to be deprived of air which affects their normal breathing could be considered to fall within the definition." Their examples of what could constitute suffocation include: putting a hand over the mouth and nose compressing the chest, any other force or suppression applied to a person to cause a restriction of breath Whether an image depicts strangulation or suffocation “will be a question of fact for the court in each case.” Is a hand on the neck choking? It's unclear, but unless pressure is being applied, a hand on the neck would not seem to meet the definition supplied by the government. Could it cover gagging or deepthroating? Potentially, as those acts tend to obstruct the airway. The government's equality assessment says the offense "could cover behaviours such as 'gagging'". Could it cover facesitting? Plausibly, if the nose and mouth are obstructed. In 2014, the British Board of Film Classification reportedly considered facesitting "without breathing restriction" to be acceptable under its standards, but not "as a breathing restriction or any other form of smothering."  That is a separate regulatory regime from the new criminal offense, but it may provide some indication of how facesitting will be judged. Does the content have to look dangerous? No. The government says the offense removes "the need to prove whether it appears to be life-threatening". Does it matter if the performers consented, or if the act was simulated? No. The offense's elements don't mention consent or simulation. The test is whether the image "explicitly and realistically" depicts the act and the people appear real. Does AI-generated content count? Yes, if it's realistic. Possession, publication, and existing content What does "publish" mean? The law defines publishing a piece of content as "giving or making it image available to another person by any means." Government guidance says that publishing "could include uploading, posting, sending, sharing or distributing an image" in the UK. What does "possess" mean? The government's guidance says possessing content generally means "having custody or control of it." That could include content that is "stored on a device, retained in a personal account or cloud, saved in files, or otherwise kept physically or virtually" in the United Kingdom. Creating content counts as possessing it. According to a government memo: "Once you create an image, you possess it, so the effect of the possession offence is to generally prohibit the creation of pornographic images portraying strangulation and suffocation." What about content already on my site? The guidance says: "Publication can also be a continuing act. If you have uploaded, posted or otherwise made an image covered by these offences available whether online or offline, you will need to remove it and stop making it available" to people in the UK before November 6, 2026. What about copies we store but don't distribute? According to the guidance: "Possession is a continuing act. If you already possess an image covered by these offences, you will need to permanently delete it or otherwise get rid of it before 6 November 2026." This may include backups, archives, and moderation queues if located or accessible in the UK. Enforcement, penalties, and defenses Who will enforce the law? Starting November 6, 2026, the law will be enforced by a variety of bodies in the criminal legal system. Each does something different: Police investigate suspected offenses. The Crown Prosecution Service (CPS) decides whether to bring charges. Courts decide whether a specific piece of content violates the law. Ofcom can issue fines for failure to prevent UK users from encountering illegal choking content under the Online Safety Act. How are police investigations likely to arise? That's impossible to predict. The best evidence we have for how the new law will be policed is how the 2009 "extreme pornography" law was implemented. A 2017 study looked at 16 "extreme pornography" cases. All of the cases followed a “chance discovery.” The images were usually found while police executed a warrant for something else, and sometimes during visits to registered sex offenders’ homes or after a tip-off. The Metropolitan Police advise individuals to report "extreme pornographic images" to them. The government's impact assessment bases its estimate of 87 annual prosecutions under the new law on existing possession of extreme pornography and obscene publications prosecution data. It does not break down how many of these are expected to stem from possession vs. publication. Can creators who appear in the content still sell it? No. The government was quite open about that fact that it wants to "generally prohibit the creation" of choking content and that it will target entities that publish choking content "for commercial gain." What other defenses are there? The law offers three possible defenses for anyone charged with the offense: that the person had a legitimate reason for publishing the content or sharing it with particular people that the person had not seen the content and did not know or have any reason to  suspect that it was illegal that the person directly participated in the act portrayed, the act did not involve the infliction of any non-consensual harm on any person, and the person only published the image to other persons who directly participated. What counts as a "legitimate reason" is unknown and having one of these defenses does not prevent you from being prosecuted. My company is outside the UK. Does this apply to me? Yes. Can a company be prosecuted, or only individuals? The law makes a company criminally liable when a senior manager commits an offense within their authority More information Where can I get more information about the law? FSC consulted UK lawyer @MylesJackman for this article. He is an expert on the UK's obscenity and extreme pornography laws. freespeechcoalition.com/uk-c…
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
Is this really the world we want to live in?
This is such a bleak story about what it's like to try to land a job right now. nytimes.com/interactive/2026…
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
I am certain of this: I am a full time emergency psychiatrist and a serious suicidologist, and @amybarnhorst is fully right: most of the emergency cases of suicidal ideation I see would be far more helped by social, problem solving, and structural supports than any pills /6
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
12) If someone trusts you and opens up about low feelings or suicidal thoughts, LISTEN. Ask permission to provide advice, and admit that your advice may sound trite. Offer to help ALONGSIDE, not tell them what to do. YOU can call a hotline and ask for help on how to help someone.
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
The diabetes genetics shenanigans that is going on right now serves as a good example of where many people misunderstand what heritability means. Fundamentally, when we say something is XX percent genetic or whatever, which is usually from a heritability estimate, we are describing how much of the variation in that trait or disease within a specific population can be attributed to genetic differences. Nothing about this tells us whether a disease is caused by genetics. Imagine scurvy, as a simple example. Let's say that scurvy is XX percent heritable because there are genetic differences that influence how susceptible someone is in developing scurvy. That stuff might matter in a population with a low intake of vitamin C, but the disease itself is still caused by low vitamin C, not genes. Type 2 diabetes is more complex, but the same principle applies. Genetics impact how susceptible someone is to developing it, but they don't cause it. The cause is excessive fat accumulation within the liver and pancreas that drive dysfunction of these organs. And focusing on genetics isn't helpful anyway because what are you supposed to do about it? It's a purely external locus of control. Even if genetics influence susceptibility, the question always comes back to agency: what can you do to mitigate that risk?
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
For those who refuse to read the articles about this case. She had a babysitter coming in the mornings to check in, make lunches, get them off to school, and prep dinner for them. All the 14 year old had to do was help them get inside after school. Microwave dinner. Get kids in bed and text mom updates. This was a work trip and they threatened to fire her if she did not go. The father has abuse charges and the police handed him their kids on top of arresting her.
A 50-year-old woman was arrested after getting off a plane after authorities said she left her four children home alone for four days while she traveled to Las Vegas for work: bit.ly/3UlVZeA
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
(˃͈ દ ˂͈ ༶ )
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
“i’m tired boss”
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
what the fuck is this about
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
you have to understand: string theorists are far too practical and grounded to care about mathematical rigor. they are rugged, no-nonsense pragmatists, uninterested in fruitless abstractions seemingly divorced from testable reality.
Replying to @Quasilocal
Existence of Yang Mills? It’s just tying up a lose end for the hyper mathematically minded. I don’t think any physicist gives af. We have been doing precision calculations for decades. Of course it exists. But sure, would be nice to have a proof.
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
By default, sunscreen is illegal in schools. The Skin Cancer Foundation is trying to make sunscreens legal in school. Sunscreens are illegal because US classifies sunscreens as over the counter drugs. (This is also why the US is 20+ years behind in legalizing sunscreens widely used in Korea and Europe.) A Virginia mom told me her kid goes without sunscreen because of this rule. Before school, she’ll put it on at 8am. Sunscreen only lasts about 2 hours - there’s no way for her preschooler to reapply it during the day. Virginia bans self-application of sunscreen unless a child is nine years old. For a teacher to apply sunscreen, Virginia requires 1. written permission from parents 2. a written record of application with the amount and type applied, day and time, name of caregiver, any error, and 3. Sunscreen must be in the original container and labeled with the child’s name. Doing this for all 12+ kids in your classroom is a lot. So teachers don't do it. The law requires every kid bring their own sunscreen. A teacher can’t buy a pound of sunscreen to make sure low-income kids also have access. The result of all of these: kids go without sunscreen. This wouldn’t happen if sunscreen was classified as a cosmetic, like it is in Europe. Have any other parents encountered issues like this?
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
Also, this whole “overstayed for four years” thing could be misleading. Here’s a real case of someone I know, again, not my husband. You enter with a tourist visa in 2021 to attend a relative’s wedding. While you’re visiting, TPS is granted to all Venezuelans currently in the country, and you’re legally welcome to stay through this blanket amnesty program. You’re issued a social security number. You’re issued a work permit. You’re issued a driver’s license. You file a W-2 and pay taxes. In November 2025, TPS is discontinued. You’re now immediately “illegal.” Your last visa, the tourist visa, expired six months after you arrived, in mid 2021, and the government would consider you to have overstayed that visa for four years. How is this possible, you ask? This person was continuously legal? How can you retroactively declare someone illegal during that four year period? This is the girl math that’s being done and why I distrust the DHS narrative about Samuel Sey, who manifestly didn’t consider himself to be an illegal alien and voluntarily went to an airport.
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
I remember back when we thought that with infinite amount of compute and sampling we would predict protein-ligand binding with experimental accuracy for all known proteins and any arbitrary ligand. What we found instead was that there are aspects of the physics and chemistry like buried waters, non-standard tautomers, crowding and weird weak interactions that we didn’t even know about. I’m very optimistic about AI expanding the scope of what we can successfully model and predict, but you cannot simulate your way out of what’s simply unknown.
If you had an exponential amount of compute you could solve simulate biology exactly and wouldn't need to run any experiments. Some of you will think "of course, but that's an unrealistic assumption" and others will think "no, you need experiments even with that much compute. That's just How It's Done". You would of course need evaluations once you have a solution, but you don't in principle need experiments to find it: Experiments are a way to save compute, dating from a time when it was much more expensive. And I think the presentation is exponential but real systems aren't irreducibly exponential. AlphaFold worked, after all.
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
Replying to @doctormorphh
yes, i have great contempt for your ilk and think you are stupid
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Catboy physicist 🏳️‍🌈🧶⚛️ retweeted
I’m seeing a lot of uninformed takes, like this one, about cell simulation feasibility. I wanted to contribute some facts. Alphafold works for predicting a subset of static structures (not how a protein structure changes shape under forces) on 1) well-ordered regions (not intrinsically disordered regions or long flexible loops) and 2) on proteins with plenty of evolutionary relatives (no orphan proteins). Alphafold solved this subset of static structure prediction with a dataset that took 50 years (PDB; 1971 to ~2020) to collect. It did not solve protein dynamics or how proteins fold into their shapes. Those remain unsolved. Cell simulation is vastly more complex and data hungry than any of this. Exact cell simulation means solving quantum equations for every atom and is totally intractable. But all approximations rely on - and are bottlenecked by - data, not compute. So the extrapolation from “alphafold worked” to “therefore cell simulation is feasible” assumes far too much.
If you had an exponential amount of compute you could solve simulate biology exactly and wouldn't need to run any experiments. Some of you will think "of course, but that's an unrealistic assumption" and others will think "no, you need experiments even with that much compute. That's just How It's Done". You would of course need evaluations once you have a solution, but you don't in principle need experiments to find it: Experiments are a way to save compute, dating from a time when it was much more expensive. And I think the presentation is exponential but real systems aren't irreducibly exponential. AlphaFold worked, after all.
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