Max Tegmark: Is mathematics invented or discovered?
How synchronous firefly flashes illuminate the physics of complex systems
Orit Peleg writes: In the still of the Tennessee night, my colleagues and I are watching thousands of dim little orbs of light, moving peacefully in the forest around us. We try to guess where the next flash will appear, but the movements seem erratic, even ephemeral. This summer, as we set up our cameras and tents, I feel a crippling sense of dread. I had brought us all up here to the Great Smoky Mountains National Park, an unlikely…
Eternal change for no energy: A time crystal finally made real
Natalie Wolchover writes: In a preprint posted online Thursday night, researchers at Google in collaboration with physicists at Stanford, Princeton and other universities say that they have used Google’s quantum computer to demonstrate a genuine “time crystal.” In addition, a separate research group claimed earlier this month to have created a time crystal in a diamond. A novel phase of matter that physicists have strived to realize for many years, a time crystal is an object whose parts move in…
Can consciousness be explained by quantum physics?
Some scientists believe consciousness is generated by quantum processes, but the theory is yet to be empirically tested. vitstudio/Shutterstock By Cristiane de Morais Smith, Utrecht University One of the most important open questions in science is how our consciousness is established. In the 1990s, long before winning the 2020 Nobel Prize in Physics for his prediction of black holes, physicist Roger Penrose teamed up with anaesthesiologist Stuart Hameroff to propose an ambitious answer. They claimed that the brain’s neuronal system…
Is the universe open-ended?
Caleb Scharf writes: One of my favorite albeit heavily paraphrased quotes from Albert Einstein is his assertion that the most incomprehensible thing about the universe is that it is comprehensible. (What he actually said, in his 1936 work “Physics and Reality,” is more longwinded, and includes a digression into Immanuel Kant and the meaning of “comprehensibility,” but he does write “… the eternal mystery of the world is its comprehensibility.”) In truth, this statement holds back a little. The greater…
Is reality a game of quantum mirrors? A new theory suggests it might be
Jurik Peter / Shutterstock By Peter Evans, The University of Queensland Imagine you sit down and pick up your favourite book. You look at the image on the front cover, run your fingers across the smooth book sleeve, and smell that familiar book smell as you flick through the pages. To you, the book is made up of a range of sensory appearances. But you also expect the book has its own independent existence behind those appearances. So when you…
The value of the Hubble Constant and the fate of the universe
Corey S Powell writes: What determines our fate? To the Stoic Greek philosophers, fate is the external product of divine will, ‘the thread of your destiny’. To transcendentalists such as Henry David Thoreau, it is an inward matter of self-determination, of ‘what a man thinks of himself’. To modern cosmologists, fate is something else entirely: a sweeping, impersonal physical process that can be boiled down into a single, momentous number known as the Hubble Constant. The Hubble Constant can be…
Is a grand theory of everything finally within reach?
James Wells writes: When trying to explain what motivates me as a physicist, the film A Passage to India (1984) comes to mind. Based on the play by Santha Rama Rau, adapted from the novel by E M Forster, it describes the fallout from a rape case in the fictional city of Chandrapore, during the British Raj in India in the 1920s. What keeps the viewer’s attention is the subtlety of the relationships between the characters – particularly the fragile…
With constructor theory, the physicist, Chiara Marletto, invokes the impossible
Amanda Gefter writes: They say that in art, constraints lead to creativity. The same seems to be true of the universe. By placing limits on nature, the laws of physics squeeze out reality’s most fantastical creations. Limit light’s speed, and suddenly space can shrink, time can slow. Limit the ability to divide energy into infinitely small units, and the full weirdness of quantum mechanics blossoms. “Declaring something impossible leads to more things being possible,” writes the physicist Chiara Marletto. “Bizarre…
A tiny particle’s wobble could upend the known laws of physics
Dennis Overbye writes: Evidence is mounting that a tiny subatomic particle seems to be disobeying the known laws of physics, scientists announced on Wednesday, a finding that would open a vast and tantalizing hole in our understanding of the universe. The result, physicists say, suggests that there are forms of matter and energy vital to the nature and evolution of the cosmos that are not yet known to science. “This is our Mars rover landing moment,” said Chris Polly, a…
Physicists nail down the ‘magic number’ that shapes the universe
Natalie Wolchover writes: As fundamental constants go, the speed of light, c, enjoys all the fame, yet c’s numerical value says nothing about nature; it differs depending on whether it’s measured in meters per second or miles per hour. The fine-structure constant, by contrast, has no dimensions or units. It’s a pure number that shapes the universe to an astonishing degree — “a magic number that comes to us with no understanding,” as Richard Feynman described it. Paul Dirac considered…
Physics and information theory give a glimpse of life’s origins
Natalie Elliot writes: How did life originate? Scientists have been studying the question for decades, and they’ve developed ingenious methods to try to find out. They’ve even enlisted biology’s most powerful theory, Darwinian evolution, in the search. But they still don’t have a complete answer. What they have hit is the world’s most theoretically fertile dead end. When scientists look for life’s origins, they usually work in one of two directions. They work backwards in time through the record of…
The hidden magnetic universe begins to come into view
Natalie Wolchover writes: Anytime astronomers figure out a new way of looking for magnetic fields in ever more remote regions of the cosmos, inexplicably, they find them. These force fields — the same entities that emanate from fridge magnets — surround Earth, the sun and all galaxies. Twenty years ago, astronomers started to detect magnetism permeating entire galaxy clusters, including the space between one galaxy and the next. Invisible field lines swoop through intergalactic space like the grooves of a…
Donald Trump is lying about taking hydroxychloroquine, a lot of people say
Vogue reports: President Donald Trump announced at a White House event on Monday that he has been taking the antimalarial drug hydroxychloroquine for “a couple of weeks” as a preventive measure against COVID-19. A lot of people don’t believe him. Immediately after the startling announcement, dozens of critics took to Twitter to doubt the president’s claim. “Raise your hand if you think that Trump is lying about taking #Hydroxychloroquine,” tweeted the widely followed health advocate Peter Morley. “I’m gonna go…
Lunch with Freeman Dyson
Siobhan Roberts writes: Lunchtime in the cafeteria at the Institute for Advanced Study in Princeton, N.J. — sometimes called the Institute for Advanced Dining — is a heady scene, and Freeman Dyson, who died last week at 96, was a regular fixture, arriving with reading material tucked under his arm. One day about 10 years ago, Dr. Dyson put down his tray of food at the physics table and joined the conversation. Nima Arkani-Hamed, a professor in the institute’s School…
Do we live in a multiple universe?
David J. Eicher writes: Decades of astrophysical research beginning in the late 19th century established the universe as we see it, culminating with the Big Bang theory. We now know the universe is about 13.8 billion years old and at least 150 billion trillion miles across. But in recent years, astronomers have begun to address a staggering possibility — the universe we can observe, and in which we live, may be one of many that makes up the cosmos. The…