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Continue reading “What If We Live in a Superdeterministic Universe?” »
One of the oldest tools in computational physics — a 200-year-old mathematical technique known as Fourier analysis — can reveal crucial information about how a form of artificial intelligence called a deep neural network learns to perform tasks involving complex physics like climate and turbulence modeling, according to a new study.
The discovery by mechanical engineering researchers at Rice University is described in an open-access study published in the journal PNAS Nexus, a sister publication of the Proceedings of the National Academy of Sciences.
“This is the first rigorous framework to explain and guide the use of deep neural networks for complex dynamical systems such as climate,” said study corresponding author Pedram Hassanzadeh. “It could substantially accelerate the use of scientific deep learning in climate science, and lead to much more reliable climate change projections.”
It’s called the Einstein Probe and it’s meant to observe the changing universe.
China has ambitious plans to launch a new X-ray astronomical satellite called the Einstein Probe (EP) at the end of this year. This is according to a report by the ChinaDaily.
“The satellite has entered the final stage of development,” he said at the recent 35th National Symposium on Space Exploration.
Continue reading “China to launch lobster eye-like X-ray astronomical satellite this year” »
In this Big Think interview, theoretical physicist Sean Carroll discusses the concept of time and the mysteries surrounding its properties. He notes that while we use the word “time” frequently in everyday language, the real puzzles arise when we consider the properties of time, such as the past, present, and future, and the fact that we can affect the future but not the past.
Carroll also discusses the concept of entropy, which is a measure of how disorganized or random a system is, and the second law of thermodynamics, which states that there is a natural tendency for things in the Universe to go from a state of low entropy to high entropy — in other words, from less disorganized to more disorganized. He explains that the arrow of time, or the perceived difference between the past and the future, arises due to the influence of the Big Bang and the fact that the Universe began in a state of low entropy.
In 1949 physicist Chien-Shiung Wu devised an experiment that documented evidence of entanglement. Her findings have been hidden in plain sight for more than 70 years.
Astrophysicists in Australia have shed new light on the state of the universe 13 billion years ago by measuring the density of carbon in the gases surrounding ancient galaxies.
The study, published in Monthly Notices of the Royal Astronomical Society, adds another piece to the puzzle of the history of the universe.
“We found that the fraction of carbon in warm gas increased rapidly about 13 billion years ago, which may be linked to large-scale heating of gas associated with the phenomenon known as the Epoch of Reionization,” says Dr. Rebecca Davies, ASTRO 3D Postdoctoral Research Associate at Swinburne University of Technology, Australia and lead author of the paper describing the discovery.
There’s a mystery happening in some satellites facing the sun, and scientists from the National Institute of Standards and Technology (NIST) and the Laboratory for Atmospheric and Space Physics (LASP) are on the case. The team has been trying to figure out what is clouding up and compromising the performance of tiny, thin metal membranes that filter sunlight as it enters detectors that monitor the sun’s ultraviolet (UV) rays.
These detectors can warn us about impending solar storms—bursts of radiation from the surface of the sun—that could reach Earth and temporarily disrupt communications or interfere with GPS readings.
Last year, the team disproved the prevailing theory: that this clouding was a buildup of carbon on the surface of the filters from organic sources stowing away on the satellite.
A team of physicists and material scientists at the University of Colorado has developed a way to better insulate double-paned glass used for windows by adding a transparent aerogel. In their paper published in the journal Nature Energy the group describes how their aerogel is made and how much of a boost in energy efficiency can be expected from windows using the material. Nature Energy has also published a Research Briefing in the same journal issue that outlines the work done by the team.
Since most homeowners prefer to have windows that allow them to see outside, heat loss is inevitable. Over the past several decades, heat loss from windows has been improved by adding a second pane of glass —the two panes are typically separated by a gap of insulating air. Still, such windows do not provide nearly the same degree of insulation as insulated walls. In this new approach, the team in Colorado has come up with a way to improve the insulation properties of double-paned glass.
To make the aerogel (a gel with pockets of air in it), the research team soaked nanofibers of cellulose extracted from wood in water. Next, the wood nanofibers were removed and were then dunked in an ethanol solution. Once saturated, the nanofibers were heated in a pressurized oven—this forced the ethanol pockets to be replaced with air. Next, the nanofibers, which were transparent, were coated with a water-repellent material to prevent condensation when situated between panes of glass.
“Our instincts of time and causation are our deepest, strongest instincts that physicists and philosophers—and humans—are loath to give up,” said one scientist.
Retraction undermines the bold claim by physicists who said their material conducted electricity without resistance at 15 ˚C.
