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"Three-Dimensional Computer Simulations Have Solved The Mystery Of Why Doomed Stars Explode"

"Now, work posted online shows how artificial intelligence (AI) can easily produce accurate emulators that can accelerate simulations across all of science by billions of times."

Much of current science deals with even more complicated systems, and similarly lacks exact solutions. Such models have to be "computational" - describing how a system changes from one instant to the next. But there is no way to determine the exact state at some time in the future other than by "simulating" its evolution in this way. Weather forecasting is a familiar example; until the advent of computers in the 1950s, it was impossible to predict future weather faster than it actually happened.

"Japanese supercomputer simulations showed that wearing two masks gave limited benefit in blocking viral spread compared with one properly fitted mask. The findings in part contradict recent recommendations from the U.S. Centers of Disease Control and Prevention (CDC) that two masks were better than one at reducing a person's exposure to the coronavirus. Researchers used the Fugaku supercomputer to model the flow of virus particles from people wearing different types and combinations of masks, according to a study released on Thursday by research giant Riken and Kobe University."

"But, as he and other modellers warn, much information about how SARS-CoV-2 spreads is still unknown and must be estimated or assumed - and that limits the precision of forecasts. An earlier version of the Imperial model, for instance, estimated that SARS-CoV-2 would be about as severe as influenza in necessitating the hospitalization of those infected. That turned out to be incorrect."

"According to Derek & Laura Cabrera, "wicked problems result from the mismatch between how real-world systems work and how we think they work". With systems thinking, there is constant testing and feedback between the real world, in all its complexity, and our mental model of it. This openness to test and look for feedback led Dr. Fisman to change his mind on the airborne spread of the coronavirus."

"The model takes a two-pronged approach. First, it focuses on trends present in the region, looking at geostatistics and historical data from Prodes, the annual government monitoring system for deforestation in the Amazon. Understanding what has happened can help make predictions more precise. When already deforested areas are recent, this indicates gangs are operating in the area, so there's a higher risk that nearby forest will soon be wiped out. Second, it looks at variables that put the brakes on deforestation - land protected by Indigenous and quilombola (descendent of rebel slaves) communities, and areas with bodies of water, or other terrain that doesn't lend itself to agricultural expansion, for instance - and variables that make deforestation more likely, including higher population density, the presence of settlements and rural properties, and higher density of road infrastructure, both legal and illegal."

"A digital twin is a virtual representation of a real system - a building, the power grid, a city, even a human being - that mimics the characteristics of the system. A digital twin is more than just a computer model, however. It receives data from sensors in the real system to constantly parallel the system's state."

"Because trends in data only become discernible with time, Masters believes it will be five or 10 years before we have a firm handle on what's going on."

"The algorithm at play is performing what's commonly referred to as predictive policing. Using years - and sometimes decades - worth of crime reports, the algorithm analyses the data to identify areas with high probabilities for certain types of crime, placing little red boxes on maps of the city that are streamed into patrol cars."

"Fear of data-mining of healthcare could be costing as many as 100,000 lives a year, according to Google's Larry Page. Speaking out in response to fears over his company's vast haul of personal information, Page made the case that not only is Google not going too far with collecting and analysing such information - it's not going far enough."