Attention to the Unseen

AFP reports: Scientists have long known that light can sometimes appear to exit a material before entering it – an effect dismissed as an illusion caused by how waves are distorted by matter. Now, researchers at the University of Toronto, through innovative quantum experiments, say they have demonstrated that “negative time” isn’t just a theoretical idea – it exists in a tangible, physical sense, deserving closer scrutiny. The findings, yet to be published in a peer-reviewed journal, have attracted both…

Read More Read More

Zack Savitsky writes: Life is an anthology of destruction. Everything you build eventually breaks. Everyone you love will die. Any sense of order or stability inevitably crumbles. The entire universe follows a dismal trek toward a dull state of ultimate turmoil. To keep track of this cosmic decay, physicists employ a concept called entropy. Entropy is a measure of disorderliness, and the declaration that entropy is always on the rise — known as the second law of thermodynamics — is…

Read More Read More

SciTechDaily reports: A groundbreaking quantum theory has allowed researchers to define the exact shape of a single photon for the first time. Scientists at the University of Birmingham, whose work is featured in Physical Review Letters, have delved into the intricate behavior of photons — individual particles of light. Their research reveals how photons are emitted by atoms or molecules and how their shape is influenced by the surrounding environment. This complex interaction gives rise to infinite possibilities for light…

Read More Read More

Anil Ananthaswamy writes: Imagine standing on a railway platform watching a trolley go past. A girl on the trolley drops a bright red ball. To her, the ball falls straight down. But from the platform, you see the ball traverse an arc before hitting the trolley floor. The two of you observe the same event, but from different reference frames: one anchored to the trolley and the other to the platform. The idea of reference frames has a storied history…

Read More Read More

Science Alert reports: From the winding down of clocks to the death of stars, everything seems destined to eventually grind to a halt. But there’s one really, really big thing to which this doesn’t seem to apply, at all. That’s the Universe itself, getting bigger and bigger all the time. According to our physical descriptions of how the cosmos should behave, that growth should be slowing down. Instead, measurements show it is speeding up, driven by a mysterious force known…

Read More Read More

Charlie Wood writes: Detecting a graviton — the hypothetical particle thought to carry the force of gravity — is the ultimate physics experiment. Conventional wisdom, however, says it can’t be done. According to one infamous estimate, an Earth-size apparatus orbiting the sun might pick up one graviton every billion years. To snag one in a decade, another calculation has suggested, you’d have to park a Jupiter-size machine next to a neutron star. In short: not going to happen. A new…

Read More Read More

Rupendra Brahambhatt writes: According to the theory of general relativity, a galaxy must have a certain amount of mass to be held together by gravity. However, scientists don’t see enough visible mass in many galaxies in the universe, yet gravity keeps such galaxies intact. How’s this even possible? This is where the concept of dark matter comes into play. Scientists believe that galaxies have invisible mass in the form of matter that doesn’t interact with light. The gravity holding these…

Read More Read More

Live Science reports: Quantum physicists are familiar with wonky, seemingly nonsensical phenomena: atoms and molecules sometimes act as particles, sometimes as waves; particles can be connected to one another by a “spooky action at a distance,” even over great distances; and quantum objects can detach themselves from their properties like the Cheshire Cat from Alice’s Adventures in Wonderland detaches itself from its grin. Now researchers led by Daniela Angulo of the University of Toronto have revealed another oddball quantum outcome:…

Read More Read More

Amanda Gefter writes: When Johnny Wheeler was 4 years old, splashing in the bathtub in Youngstown, Ohio, he looked up at his mother and asked, “What happens when you get to the end of things?” The question would haunt him for the rest of his life. What happens when you get to the bottom of space? What happens when you get to the edge of time? It would lead him to suggest that space-time can’t be the true fabric of…

Read More Read More

Erik Van Aken writes: A slight shift in Cleopatra’s beauty, and the Roman Empire unravels. You miss your train, and an unexpected encounter changes the course of your life. A butterfly alights from a tree in Michoacán, triggering a hurricane halfway across the globe. These scenarios exemplify the essence of ‘chaos’, a term scientists coined during the middle of the 20th century, to describe how small events in complex systems can have vast, unpredictable consequences. Beyond these anecdotes, I want…

Read More Read More