Oct 11, 2023 05:22 PM
(This post was last modified: Oct 11, 2023 05:23 PM by C C.)
An enduring Möbius strip mystery has finally been solved
https://www.sciencenews.org/article/mobi...olved-math
INTRO: Any attempt to better understand Möbius strips is bound to run into some kinks.
The twisted loops are so strange that mathematicians have struggled to answer some basic questions about them. For example: “What’s the shortest Möbius strip you can make for a paper band of a given width?”
The question hooked mathematician Richard Evan Schwartz. A mistake in a computer program almost prevented him from finding the answer. Simply messing around with strips of paper finally helped him solve the mystery... (MORE - details)
Invisible ‘demon’ discovered in odd superconductor
https://www.quantamagazine.org/invisible...-20231009/
INTRO: In 1956, David Pines formulated a phantom. He predicted the existence of seas of electric ripples that could neutralize each other, rendering the overall ocean motionless even as individual waves ebbed and flowed. The oddity, which came to be known as Pines’ demon, would be electrically neutral, and therefore invisible to light — the definition of tough to detect.
Over the decades, physicists managed to catch glimpses of demon variants. But Pines’ original demon — which would arise naturally out of electrons in metallic blocks — went undetected.
Now a team of physicists at the University of Illinois, Urbana-Champaign appears to have spotted Pines’ demon. After refining a technique for precisely tracking electrons as they ricochet off a material, the team produced and detected a series of periodic waves rippling through swarms of electrons. These waves, which physicists call “modes,” largely match Pines’ calculations. The researchers detailed their findings in Nature in August.
“These modes haven’t been seen for 70 years,” said Piers Coleman, a theoretical physicist at Rutgers University. But this new experiment, somehow, “picks up these demon modes.” (MORE - details)
Where is the boundary to the quantum world?
https://www.advancedsciencenews.com/wher...tum-world/
INTRO: To understand the behavior of tiny, microscopic entities such as elementary particles, atoms, and even molecules, it is necessary to apply the mind-bending principles of quantum mechanics. In this realm, physics takes on bizarre properties necessary to unravel the perplexing behaviors of the Universe at this level.
In stark contrast, the macroscopic world we navigate daily adheres faithfully to the more comforting and intuitive laws of classical physics, which serve as approximations to much more complex quantum laws. These classical laws, while impressively accurate for our everyday experiences, merely graze the surface of the quantum mechanics that orchestrates the Universe at its smallest scales.
However, an interesting idea has begun to take root, where many physicists believe that although the classical description of large physical systems work well, tiny deviations from classical predictions that happen on tiny scales accumulate over time, eventually resulting in the breakdown of the classical description.
This hypothetical phenomenon is known as quantum breaking, a captivating concept that challenges our understanding of the boundaries between the classical and quantum worlds.
“We know that at the fundamental level the world is quantum,” explained Sebastian Zell, a postdoctoral researcher at the Université Catholique de Louvain in Belgium, in an email. “Therefore, any classical description is only an approximation — if you look hard enough, you’ll see some signs of ‘quantumness’.
“However, a classical description yields extremely accurate results in many circumstances,” he continued. “In fact, classical physics works so well that quantum effects were only discovered a bit more than 100 years ago! So, why don’t we observe the full breakdown of the classical approximation in our everyday life?” (MORE - details)
https://www.sciencenews.org/article/mobi...olved-math
INTRO: Any attempt to better understand Möbius strips is bound to run into some kinks.
The twisted loops are so strange that mathematicians have struggled to answer some basic questions about them. For example: “What’s the shortest Möbius strip you can make for a paper band of a given width?”
The question hooked mathematician Richard Evan Schwartz. A mistake in a computer program almost prevented him from finding the answer. Simply messing around with strips of paper finally helped him solve the mystery... (MORE - details)
Invisible ‘demon’ discovered in odd superconductor
https://www.quantamagazine.org/invisible...-20231009/
INTRO: In 1956, David Pines formulated a phantom. He predicted the existence of seas of electric ripples that could neutralize each other, rendering the overall ocean motionless even as individual waves ebbed and flowed. The oddity, which came to be known as Pines’ demon, would be electrically neutral, and therefore invisible to light — the definition of tough to detect.
Over the decades, physicists managed to catch glimpses of demon variants. But Pines’ original demon — which would arise naturally out of electrons in metallic blocks — went undetected.
Now a team of physicists at the University of Illinois, Urbana-Champaign appears to have spotted Pines’ demon. After refining a technique for precisely tracking electrons as they ricochet off a material, the team produced and detected a series of periodic waves rippling through swarms of electrons. These waves, which physicists call “modes,” largely match Pines’ calculations. The researchers detailed their findings in Nature in August.
“These modes haven’t been seen for 70 years,” said Piers Coleman, a theoretical physicist at Rutgers University. But this new experiment, somehow, “picks up these demon modes.” (MORE - details)
Where is the boundary to the quantum world?
https://www.advancedsciencenews.com/wher...tum-world/
INTRO: To understand the behavior of tiny, microscopic entities such as elementary particles, atoms, and even molecules, it is necessary to apply the mind-bending principles of quantum mechanics. In this realm, physics takes on bizarre properties necessary to unravel the perplexing behaviors of the Universe at this level.
In stark contrast, the macroscopic world we navigate daily adheres faithfully to the more comforting and intuitive laws of classical physics, which serve as approximations to much more complex quantum laws. These classical laws, while impressively accurate for our everyday experiences, merely graze the surface of the quantum mechanics that orchestrates the Universe at its smallest scales.
However, an interesting idea has begun to take root, where many physicists believe that although the classical description of large physical systems work well, tiny deviations from classical predictions that happen on tiny scales accumulate over time, eventually resulting in the breakdown of the classical description.
This hypothetical phenomenon is known as quantum breaking, a captivating concept that challenges our understanding of the boundaries between the classical and quantum worlds.
“We know that at the fundamental level the world is quantum,” explained Sebastian Zell, a postdoctoral researcher at the Université Catholique de Louvain in Belgium, in an email. “Therefore, any classical description is only an approximation — if you look hard enough, you’ll see some signs of ‘quantumness’.
“However, a classical description yields extremely accurate results in many circumstances,” he continued. “In fact, classical physics works so well that quantum effects were only discovered a bit more than 100 years ago! So, why don’t we observe the full breakdown of the classical approximation in our everyday life?” (MORE - details)