Jean-Paul Thorbjornsen, an Australian man in his mid-30s, with a rural Catholic upbringing, is a founder of THORChain, a blockchain through which users can swap one cryptocurrency for another and earn fees from making those swaps. THORChain is permissionless, so anyone can use it without getting prior approval from a centralized authority. As a decentralized network, the blockchain is built and run by operators located across the globe. During its early days, Thorbjornsen himself hid behind the pseudonym "leena" and used an AI-generated female image as his avatar. But around March 2024, he revealed his true identity as the mind behind the blockchain. If there is a central question around THORChain, it is this: Exactly who is responsible for its operations?

Plus: social media firms have agreed to be assessed on how effectively they protect teens' mental health A "QuitGPT" campaign is urging people to cancel their ChatGPT subscriptions In September, Alfred Stephen, a freelance software developer in Singapore, purchased a ChatGPT Plus subscription, which costs $20 a month and offers more access to advanced models, to speed up his work. But he grew frustrated with the chatbot's coding abilities and its gushing, meandering replies. Then he came across a post on Reddit about a campaign called QuitGPT. QuitGPT is one of the latest salvos in a growing movement by activists and disaffected users to cancel their subscriptions. In just the past few weeks, users have flooded Reddit with stories about quitting the chatbot. And while it's unclear how many users have joined the boycott, there's no denying QuitGPT is getting attention.

AI is driving unprecedented investment for massive data centers and an energy supply that can support its huge computational appetite. One potential source of electricity for these facilities is next-generation nuclear power plants, which could be cheaper to construct and safer to operate than their predecessors. We recently held a subscriber-exclusive Roundtables discussion on hyperscale AI data centers and next-gen nuclear --two featured technologies on the MIT Technology Review 10 Breakthrough Technologies of 2026 list . You can watch the conversation back here, and don't forget to subscribe to make sure you catch future discussions as they happen. Demis Hassabis, CEO of Google DeepMind, summed it up in three words: "This is embarrassing." Hassabis was replying on X to an overexcited post by Sébastien Bubeck, a research scientist at the rival firm OpenAI, announcing that two mathematicians had used OpenAI's latest large language model, GPT-5, to find solutions to 10 unsolved problems in mathematics.

Plus: TikTok won't be heading to court this week The first human test of a rejuvenation method will begin "shortly" Life Biosciences, a small Boston startup founded by Harvard professor and life-extension evangelist David Sinclair, has won FDA approval to proceed with the first targeted attempt at age reversal in human volunteers. The company plans to try to treat eye disease with a radical rejuvenation concept called "reprogramming" that has recently attracted hundreds of millions in investment for Silicon Valley firms like Altos Labs, New Limit, and Retro Biosciences, backed by many of the biggest names in tech. Today, an estimated 2.2 billion people still have either limited or no access to the internet, largely because they live in remote places. But that number could drop this year, thanks to tests of stratospheric airships, uncrewed aircraft, and other high-altitude platforms for internet delivery. Although Google shuttered its high-profile internet balloon project Loon in 2021, work on other kinds of high-altitude platform stations has continued behind the scenes. Now, several companies claim they have solved Loon's problems--and are getting ready to prove the tech's internet beaming potential starting this year.

Plus: Australia's social media ban for teens has just come into force. Stardust Solutions believes that it can solve climate change--for a price. The Israel-based geoengineering startup has said it expects nations will soon pay it more than a billion dollars a year to launch specially equipped aircraft into the stratosphere. Once they've reached the necessary altitude, those planes will disperse particles engineered to reflect away enough sunlight to cool down the planet, purportedly without causing environmental side effects. But numerous solar geoengineering researchers are skeptical that Stardust will line up the customers it needs to carry out a global deployment in the next decade. MIT Technology Review Narrated: Is this the electric grid of the future?

Plus: A CDC panel voted to recommend delaying the hepatitis B vaccine for babies. If you're a longtime reader, you probably know that our newsroom selects 10 breakthroughs every year that we think will define the future . This group exercise is mostly fun and always engrossing, with plenty of lively discussion along the way, but at times it can also be quite difficult. The 2026 list will come out on January 12--so stay tuned. In the meantime, we wanted to share some of the technologies from this year's reject pile, as a window into our decision-making process. These four technologies won't be on our 2026 list of breakthroughs, but all were closely considered, and we think they're worth knowing about.

There's a lot at stake when it comes to understanding how AI is changing the economy right now. Or is the situation too nuanced for that? Hopefully, we can point you towards some answers. Mat Honan, our editor in chief, will hold a special subscriber-only Roundtables conversation with our editor at large David Rotman, and Richard Waters, columnist, exploring what's happening across different markets. Register here to join us at 1pm ET on Tuesday December 9. The event is part of the and "The State of AI" partnership, exploring the global impact of artificial intelligence.

A group of quantum physicists at Spanish firm Multiverse Computing claims to have created a version of the powerful reasoning AI model DeepSeek R1 that strips out the censorship built into the original by its Chinese creators. In China, AI companies are subject to rules and regulations meant to ensure that content output aligns with laws and "socialist values." As a result, companies build in layers of censorship when training the AI systems. When asked questions that are deemed "politically sensitive," the models often refuse to answer or provide talking points straight from state propaganda. Multiverse Computing specializes in quantum-inspired AI techniques, which it used to create DeepSeek R1 Slim, a model that is 55% smaller but performs almost as well as the original model. It allowed them to identify and remove Chinese censorship so that the model answered sensitive questions in much the same way as Western models.

Last week, an American-Israeli company that claims it's developed proprietary technology to cool the planet announced it had raised $60 million, by far the largest known venture capital round to date for a solar geoengineering startup. The company, Stardust, says the funding will enable it to develop a system that could be deployed by the start of the next decade, according to Heatmap, which broke the story. As scientists who have worked on the science of solar geoengineering for decades, we have grown increasingly concerned about emerging efforts to start and fund private companies to deploy technologies that could alter the climate of the planet. We also strongly dispute some of the technical claims that certain companies have made about their offerings. This story is part of Heat Exchange, MIT Technology Review's guest opinion series offering expert commentary on legal, political and regulatory issues related to climate change and clean energy. Can "The Simpsons" really predict the future?

DeepSeek may have found a new way to improve AI's ability to remember An AI model released by Chinese AI company DeepSeek uses new techniques that could significantly improve AI's ability to "remember." The optical character recognition model works by extracting text from an image and turning it into machine-readable words. This is the same technology that powers scanner apps, translation of text in photos, and many accessibility tools. Researchers say the model's main innovation lies in how it processes information--specifically, how it stores and retrieves data. Improving how AI models "remember" could reduce how much computing power they need to run, thus mitigating AI's large (and growing) carbon footprint. The AI Hype Index: Data centers' neighbors are pivoting to power blackouts That's why we've created the AI Hype Index--a simple, at-a-glance summary of everything you need to know about the state of the industry.