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Digital Einstein Papers Home

Digital Einstein Papers Home

http://einsteinpapers.press.princeton.edu/

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New books for the physics fan Looking to stay current on your particle physics knowledge? Here are 10 recent popular science books you might want to check out. 1. Faraday, Maxwell and the Electromagnetic Field: How Two Men Revolutionized Physics Astrology Fails the Test of Science (2) In our first article we provided an introduction to astrology. After having defined the subject, we examined the history, prevalence, and appeal of astrology. In this second article, we will see that astrology cannot pass the test of science. There is no "real world" evidence that astrology works.

Time Always Marches Forward “Time is what keeps everything from happening at once,” wrote Ray Cummings in his 1922 science fiction novel “The Girl in the Golden Atom,” which sums up time’s function quite nicely. But how does time stop everything from happening at once? What mechanism drives time forward, but not backward? In a recent study published in the journal Physical Review Letters, a group of theoretical physicists re-investigate the “Arrow of Time” — a concept that describes the relentless forward march of time — and highlight a different way of looking at how time manifests itself over universal scales.

8. How Particles and Fields Interact (an introduction) © Matt Strassler [October 9, 2012] This is article 8 in the sequence entitled Fields and Particles: with Math. Here is the previous article. In the previous article in this series, I explained that the particles of nature are quanta of relativistic fields satisfying Class 0 and Class 1 equations of motion. But what I didn’t say yet is that — fortunately — this statement is only approximately true. The real equations are always a bit more complicated, in such a way that retains this relation between particles and fields but allows for a much richer set of processes to occur, including the production of particles from the collision of other particles, the decays of some particles to other particles, and the scattering of particles off each other, as well as the formation of interesting objects such as protons and neutrons, atomic nuclei and atoms.

DARPA: We Are Engineering the Organisms That Will Terraform Mars Terraformed Mars, artist's conception. Image: Daein Ballard/Wikimedia Commons It’s no secret that the Defense Advanced Research Projects Agency is investing heavily in genetic engineering and synthetic biology. Stephen Hawking warns artificial intelligence could end mankind Prof Stephen Hawking, one of Britain's pre-eminent scientists, has said that efforts to create thinking machines pose a threat to our very existence. He told the BBC:"The development of full artificial intelligence could spell the end of the human race." His warning came in response to a question about a revamp of the technology he uses to communicate, which involves a basic form of AI. But others are less gloomy about AI's prospects.

Laura Candler's Math Problem File Cabinet Laura Candler's Math Problem Solving page is where you'll find great resources for teaching problem solving as well as a variety of math problem activity pages. Many of the items on this page are free and do not come with directions. For complete problem solving lessons, check out the Daily Math Puzzlers, a series of four leveled books that include information on how to teach problem solving as well as mixed-problem activity pages for students. Math Problem Solving Webinar Recording Mp4 Video Math Buddy Chat Free PowerPoint

Theoretical highlights The lessons we learned from the Ryu-Takayanagi formula, the firewall paradox and the ER=EPR conjecture have convinced us that quantum information theory can become a powerful tool to sharpen our understanding of various problems in high-energy physics. But, many of the concepts utilized so far rely on entanglement entropy and its generalizations, quantities developed by Von Neumann more than 60 years ago. We live in the 21st century. Why don’t we use more modern concepts, such as the theory of quantum error-correcting codes? In a recent paper with Daniel Harlow, Fernando Pastawski and John Preskill, we have proposed a toy model of the AdS/CFT correspondence based on quantum error-correcting codes. Fernando has already written how this research project started after a fateful visit by Daniel to Caltech and John’s remarkable prediction in 1999.

Mars Up Close Marc Kaufman Marc Kaufman is a science writer and national editor for The Washington Post. He lives outside of Washington, D.C. Meet The Woman Who Did Everything In Her Power To Hide Her Pregnancy From Big Data By Jessica Goldstein "Meet The Woman Who Did Everything In Her Power To Hide Her Pregnancy From Big Data" The server room at Facebook’s data center in Prineville, Ore. CREDIT: AP Photo/Facebook, Alan Brandt Janet Vertesi, assistant professor of sociology at Princeton University, had an idea: would it be possible to hide her pregnancy from big data? Thinking about technology—the way we use it and the way it uses us—is her professional life’s work.

CERN frees LHC data Today CERN launched its Open Data Portal, which makes data from real collision events produced by LHC experiments available to the public for the first time. “Data from the LHC program are among the most precious assets of the LHC experiments, that today we start sharing openly with the world,” says CERN Director General Rolf Heuer. “We hope these open data will support and inspire the global research community, including students and citizen scientists.” The LHC collaborations will continue to release collision data over the coming years.

Interactive: What Is Space? In 1915, Albert Einstein’s field equations of gravitation revolutionized our understanding of space, time and gravity. Better known as general relativity, Einstein’s theory defined gravity as curves in the geometry of space-time, overturning Isaac Newton’s classic theory and correctly predicting the existence of black holes and gravity’s ability to bend light. But a century later, the fundamental nature of space-time remains shrouded in mystery: Where does its structure come from? What do space-time and gravity look like in the subatomic quantum realm? The short answer is that we don’t know. But many physicists, writes Jennifer Ouellette in “How Quantum Pairs Stitch Space-Time,” have long “suspected a deep connection between quantum entanglement — the ‘spooky action at a distance’ that so vexed Albert Einstein — and space-time geometry at the smallest scales.”

Lasers might push spacecraft all the way to Mars in just 3 days Depending on the alignment of Mars and Earth, as well as the speed of propulsion, a spacecraft could reach the Red Planet as soon as 150 days. So far, NASA spacecraft have made 13 trips to Mars, with seven landings. The most recent — that of the Curiosity rover — took 253 days from launch on Earth to touchdown on Mars. There’s now reason to believe, however, that this journey could be significantly made faster to the point it only takes 3 days, according to a NASA researcher. Artistic rendition of a laser driven spacecraft.

Why Google doesn't care about college degrees, in 5 quotes Google isn’t big on college degrees, although the search giant is inundated with applicants touting perfect GPAs from Ivy League schools. Google’s chairman and head of hiring, Laszlo Bock, has given a few insights in the New York Times on how he sorts through a multitude of bright applicants. The upshot is that Google values the skills and experiences that candidates get in college, but a degree doesn’t tell them much about talent or grit. You don’t need a college degree to be talented

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