In the 1970s, Steven Hawking proposed that information that falls into a black hole gets destroyed, never to be retrieved. A series of breakthrough papers have now shown that’s not correct. Here’s a thread about the famous black hole information paradox:
According to Einstein’s general theory of relativity, the gravity of a black hole is so intense that nothing can escape it. Hawking’s “semiclassical” approach brought together quantum mechanics and relativity and predicted the famous information paradox.
Now, theoretical physicists have demonstrated that additional semiclassical effects emerge in older black holes, allowing information to spill out.
The mathematical key to the new work lies in a calculation called the Page curve, which reflects the changes in a black hole’s entanglement entropy as it ages.
If black holes gain then lose entanglement entropy, following the Page curve, information is able to escape.
Calculating the entanglement inside a black hole has brought together a Rube Goldberg-like succession of nearly every concept in fundamental physics: emergent space-time, quantum entanglement and quantum computers.
While physicists have no idea *how* the information gets out, almost all agree that space-time itself seems to fall apart at a black hole, implying that space-time is not the root level of reality, but an emergent structure from something deeper.
Here’s a thread about the fundamental constituents of the universe, as explained by @nattyover, with graphics by Samuel Velasco and @LucyIkkanda.
In the 1970s, physicists formed a framework that encapsulates our best understanding of nature’s fundamental order. Yet most visualizations of the Standard Model of particle physics are too simple, ignore important interconnections or are overwhelming.
The most common visualization of the Standard Model shows a periodic table of particles, but doesn’t offer insight into the relationships between them. It also leaves out key properties like “color.”
Time has fascinated the human mind for millennia. Through the vantage points of culture, physics, timekeeping and biology, we have compiled a special timeline organizing some of the efforts that humans have made to understand time. (thread) quantamagazine.org/what-is-time-a…
Western culture tends to emphasize a linear conception of time, but the ancestors of today’s Australian aboriginal peoples embraced a timeless view of nature. In Asia, followers of Hinduism and Buddhism adopted a cyclic view.
Some of the best evidence for how ancient cultures viewed time can be found in artifacts of timekeeping mechanisms, like Egyptian sundials and circular Mayan calendars.
The revered condensed matter physicist Philip Anderson passed away yesterday at the age of 97. Here is a sampling of some of Anderson’s ideas that have propelled modern physics. (Thread)
Anderson won the 1977 Nobel Prize in Physics for his discovery of what is now called Anderson localization, a phenomenon in which some waves stay within a given “local” region rather than advancing freely.
Quanta covered new advances in the understanding of Anderson localization in 2017 in an article that later became an episode of the Quanta Science Podcast: quantamagazine.org/mathematicians…
Most of us imagine the universe as extending forever in all directions. Does it have to be so? (Thread) quantamagazine.org/what-is-the-ge…
After all, because of the planet’s very subtle curvature, everyone once thought that the Earth was flat. Now, of course, we know it’s shaped like a sphere.
Is our contemporary mental model of a vast, infinitely expansive universe similarly flawed?
Rock-paper-scissors is a classic problem in game theory that’s also a touchstone concept in biology because of its relevance to evolution and ecology. ✊🤚✌️
Here’s why.
A thread: (1/9)
Since 1960, biologists have pondered “the paradox of the plankton”: How can ecosystems stably hold so many competing species? Why doesn’t the fittest eliminate the rest? (2/9)
One possible answer is the kill-the-winner hypothesis: As a predator thrives, it attracts more predators of itself. That response should in theory stabilize the system. (3/9)