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Comment Re:I Wonder ... (Score 1) 201

Coriolis force is a fictitious force (like Centrifugal force). Anyway, force has to move a distance to create work (energy). Wind energy is the result of wind, which results from large convection currents due to temperature differences on earth, both due to latitude (tilt of earth) and difference in specific heat (thermal capacity) between land and sea. Since these uneven temperatures are caused by sun's radiation, wind energy is just solar energy. Wind mills are parts of a giant heat engine (just as a turbofan in a jet engine). So, windmills will not result in slowdown in rotation of earth. But, they will lead to a miniscule amount of cooling locally (the wind on the outlet side will be a tad cooler than on the inlet side). However, this will all get evened out since most of the power produced eventually becomes heat anyway.

Comment Why so much excitement? (Score 1) 154

House building is a fairly "commodity" activity. The craft of the trade hasn't changed much in at least 30 years. We have plenty of land. With remote work for many occupations in the post-pandemic era, premium on location has come down. Why not trust capitalism to solve the problem? Would you be equally excited if some company were try to buy "all" corn or wheat? All oil? All cars? Then why fear house buying?

Comment Re:Herd immunity before a vaccine (Score 1) 132

Recent estimate for U.S. is 90 million. Matches well with India's 300 million. "Officials say the drop is likely due to a higher number of people who've had the virus than official counts suggest, as many as 90 million people, and fewer people traveling than did over the winter holidays" https://ancillary-proxy.atarimworker.io?url=https%3A%2F%2Fwww.dailymail.co.uk%2Fhe...

Submission + - HUBBLE OBSERVATIONS SUGGEST A MISSING INGREDIENT IN DARK MATTER THEORIES (hubblesite.org)

bsharma writes: A dark matter measurement technique involves measuring how dark matter's gravity in a massive galaxy cluster magnifies and warps light from a distant background galaxy. This phenomenon, called gravitational lensing, produces smeared images of remote galaxies and occasionally multiple copies of a single image.

A recent study of 11 hefty galaxy clusters found that some small-scale clumps of dark matter are so concentrated that the lensing effects they produce are 10 times stronger than expected. These concentrations are associated with individual cluster galaxies.

Researchers using the Hubble Space Telescope and the European Southern Observatory's Very Large Telescope in Chile discovered with unprecedented detail smaller-scale distorted images of remote galaxies nested like Matryoshka dolls within the larger-scale lens distortions in each cluster's core, where the most massive galaxies reside.

This unexpected discovery means there is a discrepancy between these observations and theoretical models of how dark matter should be distributed in galaxy clusters. It could signal a gap in astronomers' current understanding of the nature of dark matter.

Submission + - The doctor who ordered the Bay Area's coronavirus lockdown (mercurynews.com)

bsharma writes: She is the Bay Area’s Anthony Fauci, Santa Clara County’s most “essential” employee, the one who banished us from Sharks hockey games, canceled her own daughter’s high school prom — and eventually shut in 6 million Bay Area residents in six neighboring counties to slow the stampede of a deadly pandemic...

Submission + - Hearing loss of US diplomats in Cuba is blamed on covert device (bostonglobe.com)

bsharma writes: The two-year-old U.S. diplomatic relationship with Cuba was roiled Wednesday by what U.S. officials say was a string of bizarre incidents that left a group of American diplomats in Havana with severe hearing loss attributed to a covert sonic device.

In the fall of 2016, a series of U.S. diplomats began suffering unexplained losses of hearing, according to officials with knowledge of the investigation into the case. Several of the diplomats were recent arrivals at the embassy, which reopened in 2015 as part of former President Barack Obama’s reestablishment of diplomatic relations with Cuba.

Some of the diplomats’ symptoms were so severe that they were forced to cancel their tours early and return to the United States, officials said. After months of investigation, U.S. officials concluded that the diplomats had been exposed to an advanced device that operated outside the range of audible sound and had been deployed either inside or outside their residences. It was not immediately clear if the device was a weapon used in a deliberate attack, or had some other purpose.

Submission + - National Solar Observatory predicts shape of solar corona for august eclipse (phys.org)

bsharma writes: August 21st will bring a history-making opportunity for the entire United States. On that day, every person in the country, including Hawaii and Alaska, will have an opportunity to witness at least a partial solar eclipse as the moon moves in front of the Sun. If you have the good fortune to be along the path of totality, stretching from Oregon to South Carolina, you will get to witness one of the most awe-inspiring views in nature – the wispy wonders of the solar corona.

Comment In theory, such machines exist (Score 1) 326

Studying them is part of course in "Theory of Computation" taught in Computer Science. https://ancillary-proxy.atarimworker.io?url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2F... Interestingly, even with "infinitely" fast machines, there will still be problems that may not be computable. https://ancillary-proxy.atarimworker.io?url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2F...

Comment Re:Can someone explain in laymans terms how.... (Score 1) 334

There is a possibility that we may discover new forms (phases) of matter. For example study of Bose-Einstein condensate ( https://ancillary-proxy.atarimworker.io?url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2F... ) has revealed a lot of new physics. Study of once similarly obscure Superconductivity has given rise to a lot of new physics. Imagine if Hydrogen metallization experiment would lead to a new method to cause nuclear fusion. It may also help to answer the fundamental question: What is matter? and Why does it exist?

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