Different open-ended generation tasks require different degrees of output diversity. However, current LLMs are often miscalibrated. They collapse to overly homogeneous outputs for creative tasks and hallucinate diverse but incorrect responses for factual tasks. We argue that these two failure modes are unified by, and can both be addressed by, the notion of effective generation space size (GSS) -- the set of semantically distinct outputs a model considers for a prompt. We present GSSBench, a task suite of prompt pairs with ground-truth GSS relationships to assess different metrics and understand where models diverge from desired behavior. We find that hallucination detection metrics, particularly EigenScore, consistently outperform standard diversity and uncertainty quantification metrics, while using only model internals, providing interpretable insights into a model's internal task representations. We demonstrate three applications of GSS: (1) detecting prompt ambiguity and predicting clarification questions for better grounding, (2) interpreting overthinking and underthinking in reasoning models, and (3) steering models to expand their generation space to yield high-quality and diverse outputs.

OpenAI plans to allow a wider range of content, including erotica, on its popular chatbot ChatGPT as part of its push to treat adult users like adults, says its boss Sam Altman. In a post on X on Tuesday, Mr Altman said upcoming versions of the popular chatbot would enable it to behave in a more human-like way - but only if you want it, not because we are usage maxxing. The move, reminiscent of Elon Musk's xAI recent introduction of two sexually explicit chatbots to Grok, could help OpenAI attract more paying subscribers. It is also likely to intensify pressure on lawmakers to introduce tighter restrictions on chatbot companions. OpenAI did not respond to the BBC's requests for comment following Mr Altman's post.

The former Australian Paralympic swimmer wanted to vamp up her headshot and uploaded a full-length photo of her and prompted it really specifically that she was missing her left arm from below the elbow. But ChatGPT couldn't create the image she was asking for and despite various prompts, the results were largely the same - a woman with two arms or one with a metal device to represent a prosthetic. She asked the AI why it was so hard to create the image and it said it was because it didn't have enough data to work with. That was an important realisation for me that of course AI is a reflection of the world we live in today and the level of inequality and discrimination that exists, she says. Smith recently tried to generate the image again on ChatGPT and was amazed to find it could now produce an accurate picture of a woman with one arm, just like her.

Muskan Sharma stood up to men who tried to bully her over her clothes - and went on to win hearts and a beauty pageant. The 23-year-old, who was crowned Miss Rishikesh 2025 last week in the northern Indian state of Uttarakhand, told the BBC that even though it was a small local pageant, it made me feel like Miss Universe. Sharma's win has made headlines in India as it came after a viral video that showed her spiritedly arguing with a man who barged into their rehearsals just a day before the 4 October contest. Sharma, who wanted to be a model and participate in a pageant since I was in school, said the intruders came in just as they broke for lunch. We were sitting around, chilling, having a laugh when they walked in, she said.

Another round of terminations, combined with previous layoffs and departures, has reduced the Centers for Disease Control and Prevention workforce by about 3,000 people since January. After the latest round of mass firings at the Centers for Disease Control and Prevention over the weekend, the union that represents agency employees estimates that around 3,000 people this year--about a quarter of the agency's workforce--have departed the agency. That number includes workers affected by layoffs earlier this year, as well those who have accepted the Trump administration's "Fork in the Road" buyout program. The most recent cuts came down amidst the ongoing government shutdown. On October 10, more than 1,300 CDC employees received termination notices.

Army Secretary Dan Driscoll says the Army is developing small drones based on Ukraine lessons, envisioning every infantryman having a drone for future missions.

The gut contents act like a microscopic time machine into pre-Hispanic Mexico. Breakthroughs, discoveries, and DIY tips sent every weekday. Underneath the remains of an ancient young adult man and his preserved feces lies a microscopic world. These microorganisms beneath the cloth hold clues to what the world may have looked like hundreds of years ago. Now, a new look at a 1,000-year-old mummy called the Zimapán man could tell us what ancient Mesoamericans ate, where they lived, and show us how much our world has changed since.

Some migrants coming to the UK will need to speak English to an A-level standard under tougher new rules set to be introduced by the government. Applicants will be tested in person on their speaking, listening, reading and writing at Home Office-approved providers, with their results checked as part of the visa process. The changes, which come into force from 8 January 2026, form part of wider plans to cut levels of immigration to the UK outlined in a white paper in May. Home Secretary Shabana Mahmood said: If you come to this country, you must learn our language and play your part. Those applying for skilled worker, scale-up and high potential individual (HPI) visas will be required to reach B2 level - a step up from the current B1 standard which is equivalent to GCSE.

What is the Insurrection Act? Is Trump trying to dial back tensions with Brazil? Why was Letitia James indicted? Will a government shutdown hurt the economy? The United States's artificial intelligence (AI) investment boom might be an economic bubble that could burst, comparable to the dot-com bust in the early 2000s, according to the International Monetary Fund.

Why has Dutch government taken control of China-owned chipmaker Nexperia? The Dutch government has intervened to take effective control of technology group Nexperia, which is owned by Chinese group Wingtech Technology. The decision comes amid a growing rift between China and the West over the development of technology such as computer chips and semiconductors, which are essential components for the manufacture of artificial intelligence (AI) technology. Here is more about what the Dutch government announced, why and what happens next. What has the Dutch government announced?