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Domain walls, long a divisive topic in physics, may be ideal explanations for some bizarre cosmic quirks.

By Anil Ananthaswamy

“As long as they live for long enough, they will always become large cosmological beasts,” says Ricardo Ferreira, a cosmologist at the University of Coimbra in Portugal. He’s not talking about actual beasts but rather about hypothetical humongous sheets of spacetime that could divide one region of the universe from another. Such so-called domain walls are the natural outcome of theories that try to solve some of the deepest mysteries in physics, such as the origins of gravity. As Ferreira says, however, had they formed after the big bang, by today they’d be the dominant source of energy in our universe, and there’s no evidence that’s the case. So any theory invoking their existence has been considered suspect—until now, perhaps.

From the dynamical point of view, most cognitive phenomena are hierarchical, transient and sequential. Such cognitive spatio-temporal processes can be represented by a set of sequential metastable dynamical states together with their associatedions: The state is quasi-stationary close to one metastable state before a rapidion to another state. Hence, we postulate that metastable states are the central players in cognitive information processing. Based on the analogy of quasiparticles as elementary units in physics, we introduce here the quantum of cognitive information dynamics, which we term “cognon”. A cognon, or dynamical unit of thought, is represented by a robust finite chain of metastable neural states. Cognons can be organized at multiple hierarchical levels and coordinate complex cognitive information representations.

This month in 1,871, James Clerk demonstrated entropy with a thought experiment now known as’s Demon.


The American Physical Society is a nonprofit membership organization working to advance physics by fostering a vibrant, inclusive, and global community dedicated to science and society.

Growth of data eases the way to access the world but requires increasing amounts of energy to store and process. Neuromorphic electronics has emerged in the last decade, inspired by biological neurons and synapses, with in-memory computing ability, extenuating the ‘von Neumann bottleneck’ between the memory and processor and offering a promising solution to reduce the efforts both in data storage and processing, thanks to their multi-bit non-volatility, biology-emulated characteristics, and silicon compatibility. This work reviews the recent advances in emerging memristive devices for artificial neuron and synapse applications, including memory and data-processing ability: the physics and characteristics are discussed first, i.e., valence changing, electrochemical metallization, phase changing, interfaced-controlling, charge-trapping, ferroelectric tunnelling, and spin-transfer torquing. Next, we propose a universal benchmark for the artificial synapse and neuron devices on spiking energy consumption, standby power consumption, and spike timing. Based on the benchmark, we address the challenges, suggest the guidelines for intra-device and inter-device design, and provide an outlook for the neuromorphic applications of resistive switching-based artificial neuron and synapse devices.

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Physics meets machine learning.


The Progress and Promise for Science in Indonesia Regional Special Feature focuses on biodiversity and climate change, highlighting research based on the unique geology and biology of a nation comprising more than 17,600 islands, containing about 10 percent of the world’s remaining tropical forests, and home to over 300,000 species of wildlife.

Join my mailing list https://briankeating.com/list to win a real 4 billion year old meteorite! All.edu emails in the USA 🇺🇸 will WIN!Is the universe twice as old as we thought?Current estimates suggest that the Big Bang occurred 13.8 billion years ago. But today, we’re joined by Rajendra Gupta, a luminary in the field of cosmology who claims that the universe is actually 26.7 billion years old. I’ve invited him on the show so he can make a case for his claims!Professor Gupta is a theoretical physicist currently teaching astrophysics to senior undergraduate and graduate students at the University of Ottawa. His research focuses on astrophysics, cosmology, general relativity, the dynamics of the universe under evolutionary physical constants beyond the standard model, CMB, JWST, BAO, Big Bang nucleosynthesis, the large-scale structure and formation of galaxies, dark matter, and dark energy. To say I am thrilled to have him on the show for the second time would be an understatement. So, without further ado, let’s jump right in! Key Takeaways:

00:00 Intro.

01:50 Judging Rajendra’s paper.

Hausjärvi, FINLAND— A Chinese launch of the joint Sino-French SVOM mission to study Gamma-ray bursts early Saturday saw toxic rocket debris fall over a populated area.

A Long March 2C rocket lifted off from Xichang Satellite Launch Center at 3:00 a.m. Eastern (0700 UTC) June 22, sending the Space Variable Objects Monitor (SVOM) mission satellite into orbit.

The launch was declared successful by the China Aerospace Science and Technology Corporation (CASC) a short time after liftoff.