Attention to the Unseen

MIT Technology Review reports: Back in 1961, the Nobel Prize–winning physicist Eugene Wigner outlined a thought experiment that demonstrated one of the lesser-known paradoxes of quantum mechanics. The experiment shows how the strange nature of the universe allows two observers—say, Wigner and Wigner’s friend—to experience different realities. Since then, physicists have used the “Wigner’s Friend” thought experiment to explore the nature of measurement and to argue over whether objective facts can exist. That’s important because scientists carry out experiments to…

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Marcia Bartusiak writes: Poets often think of time as a river, a free-flowing stream that carries us from the radiant morning of birth to the golden twilight of old age. It is the span that separates the delicate bud of spring from the lush flower of summer. Physicists think of time in somewhat more practical terms. For them, time is a means of measuring change—an endless series of instants that, strung together like beads, turn an uncertain future into the…

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Brian Gallagher writes: In April, in the famous Faraday Theatre at the Royal Institution in London, Carlo Rovelli gave an hour-long lecture on the nature of time. A red thread spanned the stage, a metaphor for the Italian theoretical physicist’s subject. “Time is a long line,” he said. To the left lies the past—the dinosaurs, the big bang—and to the right, the future—the unknown. “We’re sort of here,” he said, hanging a carabiner on it, as a marker for the…

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  Natalie Wolchover writes: In 2014, a graduate student at the University of Waterloo, Canada, named Cohl Furey rented a car and drove six hours south to Pennsylvania State University, eager to talk to a physics professor there named Murat Günaydin. Furey had figured out how to build on a finding of Günaydin’s from 40 years earlier — a largely forgotten result that supported a powerful suspicion about fundamental physics and its relationship to pure math. The suspicion, harbored by…

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How does our world work on a subatomic level? Varsha Y S, CC BY-SA By Glenn Starkman, Case Western Reserve University The Standard Model. What dull name for the most accurate scientific theory known to human beings. More than a quarter of the Nobel Prizes in physics of the last century are direct inputs to or direct results of the Standard Model. Yet its name suggests that if you can afford a few extra dollars a month you should buy…

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David Kaiser writes: The word “predictable” first entered the English language two centuries ago. Its début came in neither a farmer’s almanac nor a cardsharp’s manual but in The Monthly Repository of Theology and General Literature, a Unitarian periodical. In 1820, one Stephen Freeman wrote a dense treatise in which he criticized the notion that human behavior—seemingly manifest “amidst the conflicting, boisterous, unreasonable wills of men, all acting, as they feel they do, their various parts with complete freedom of…

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University of Cambridge, April 27, 2018 Professor Stephen Hawking’s final theory on the origin of the universe, which he worked on in collaboration with Professor Thomas Hertog from KU Leuven, has been published today in the Journal of High Energy Physics. The theory, which was submitted for publication before Hawking’s death earlier this year, is based on string theory and predicts the universe is finite and far simpler than many current theories about the big bang say. Professor Hertog, whose…

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Charlotte Higgins writes: What do we know about time? Language tells us that it “passes”, it moves like a great river, inexorably dragging us with it, and, in the end, washes us up on its shore while it continues, unstoppable. Time flows. It moves ever forwards. Or does it? Poets also tell us that time stumbles or creeps or slows or even, at times, seems to stop. They tell us that the past might be inescapable, immanent in objects or…

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