Atomic clocks are letting physicists tighten the lasso around elusive phenomena such as dark matter.
Read more
Category: physics – Page 312
A City-Sized ‘Telescope’ Could Watch Space-Time Ripple 1 Million Times a Year
COLUMBUS, Ohio — A gravitational wave detector that’s 2.5 miles long isn’t cool. You know what’s cool? A 25-mile-long gravitational wave detector.
That’s the upshot of a series of talks given here Saturday (April 14) at the April meeting of the American Physical Society. The next generation of gravitational wave detectors will peer right up to the outer edge of the observable universe, looking for ripples in the very fabric of space-time, which Einstein predicted would occur when massive objects like black holes collide. But there are still some significant challenges standing in the way of their construction, presenters told the audience.
“The current detectors you might think are very sensitive,” Matthew Evans, a physicist at MIT, told the audience. “And that’s true, but they’re also the least sensitive detectors with which you can [possibly] detect gravitational waves.” [8 Ways You Can See Einstein’s Theory of Relativity in Real Life].
Read more
‘There is no such thing as past or future’: physicist Carlo Rovelli on changing how we think about time
Seven Brief Lessons on Physics sold over a million copies around the world. Now Rovelli is back to explore the mysteries of time. He tells Charlotte Higgins about student revolution and how his quantum leap began with an acid trip.
• Extract from Carlo Rovelli’s new book: on the elastic concept of time.
Read more
Scientists Create Beautiful Iridescent Material That Could Be Edible
What makes something red, or blue, or green? It’s all in the way light bounces off its surface. Something that primarily reflects light with shorter wavelengths will appear bluer, while something that reflects longer wavelengths will appear redder. By playing around with that principle, scientists have created a material that, much like soap bubbles and certain insect wings, displays a gorgeous iridescence—a shifting rainbow of colors they can tweak with the same surface.
Even more interestingly, the researchers made this material from common cellulose, the simple stuff that makes up paper and which can be extracted from wood, cotton, or other renewable sources. We’ve already mentioned scientists arranging cellulose fibers in a way that makes them appear incredibly white. But now instead of laying fibers, a team of physicists are molding cellulose films with tiny, regularly spaced impressions (like an upside-down Lego piece).
The outcome was a thin, single-centimeter iridescent film that reflects light based on the spacing of the dots, according to the paper published recently in Nature Photonics.
Read more
Physicists Just Discovered an Entirely New Type of Superconductivity
One of the ultimate goals of modern physics is to unlock the power of superconductivity, where electricity flows with zero resistance at room temperature.
Progress has been slow, but physicists have just made an unexpected breakthrough. They’ve discovered a superconductor that works in a way no one’s ever seen before — and it opens the door to a whole world of possibilities not considered until now.
In other words, they’ve identified a brand new type of superconductivity.
Read more
