Science

Most physicists operate under the assumption that there is a world out there that is entirely independent of us, an objective reality in which more-or-less well-defined things behave according to immutable physical laws. Yet over the past century, ever since the development of quantum theory, there have been discombobulating questions about the role of observers – not least ourselves – in the makings of reality. These questions are often brushed under the carpet, but Daniele Oriti, a theorist at the Complutense University of Madrid, prefers to confront them. Arguably, he has been pushed to do so by his work on one of the foremost challenges in modern physics: creating a quantum theory of gravity. The difficulty here is reconciling the inherently smooth picture of spac...

Participants in Friday’s event in Morningside Park gather to ceremonially hit a button to turn the park’s waterfall on. Photo: Brandon Vallejo Leaders from Columbia and New York City’s Department of Parks & Recreation gathered in Morningside Park on Friday to celebrate a major partnership to clear the park’s pond of toxic algal blooms, repair broken water pumps and restore its iconic waterfall. For the first time in seven years (other than brief testing periods), the waterfall sprang to life, and a stream of water sprayed over a wall of rocks before cascading into the pond below. The event was part of a project, initiated last year, that aims to use Columbia’s expertise to restore Morningside Park’s waterfall and pond, and to make New York City’s parks more resilient in the face...

This past summer, students from Columbia’s Master of Public Administration in Environmental Science and Policy (MPA-ESP) program participated in an Urban Ecology field trip led by Matthew Palmer, senior lecturer in the department of Ecology, Evolution and Environmental Biology at Columbia. The cohort visited three key sites in New York City—Randall’s Island, River Park and Bronx Park East—each serving as a living laboratory where students explored the intersection of natural ecosystems and urban environments. Through hands-on learning and direct observation, students deepened their understanding of the vital role urban ecology plays in fostering sustainable and resilient communities. First Stop: Randall’s Island Anne Wilson explains the public-private partnership that drives Randall...

Large language models are capable of answering a wide range of questions – but not always accuratelyJamie Jin/Shutterstock Large language models (LLMs) seem to get less reliable at answering simple questions when they get bigger and learn from human feedback. AI developers try to improve the power of LLMs in two main ways: scaling up – giving them more training data and more computational power – and shaping up, or fine-tuning them in response to human feedback. José Hernández-Orallo at the Polytechnic University of Valencia, Spain, and his colleagues examined the performance of LLMs as they scaled up and shaped up. They looked at OpenAI’s GPT series of chatbots, Meta’s LLaMA AI models, and BLOOM, developed by a group of researchers called BigScience. The research...

Growing up in the US during the oil embargo of the early 1970s, I was bombarded by public service announcements encouraging people to conserve energy. But at a very young age, I also read that “energy is always conserved”, according to physics. This baffled me. If nature automatically conserves energy, why would human efforts to do so be needed? I soon realised that physicists don’t exactly speak English. They employ a dialect full of familiar-sounding terms with unfamiliar meanings (including “conserve” and “energy”). Worse still, many words, including simple ones like “force” and “mass”, don’t even signify what physicists originally intended. Consequently, the language we use to talk about physics obscures some of our most beautiful and fascinating discoveries about...