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Enrico Fermi This week marks the 70th anniversary of a turning point in human history.It was on December 2, 1942, that Enrico Fermi ordered the control rods pulled from the nuclear reactor he had built under the west stands of the University of Chicago’s Stagg Field stadium, thereby initiating the first artificial sustained-fission reaction in human history. A cryptic message flashed the electrifying news back to Washington. “The Italian navigator has landed in the new world.”The consequences of Fermi’s success were profound. Within two and a half years, the Manhattan Project advanced to build both uranium-isotope-separation and plutonium-manufacturing facilities on...

Hubble observations of a speedy galaxy weigh on the Milky Way and indicate that our galaxy is at least a trillion times as massive as the sunMilky Way GREAT GALAXY: The Milky Way maintains a fleet of some two dozen satellite galaxies whose motions help reveal its mass. Image: NASA/ESA/Hubble Heritage Team Although scientists know the masses of the sun and Earth, it's a different story for the galaxy. Mass estimates range widely: At the low end, some studies find that the galaxy is several hundred billion times as massive as the sun whereas the largest values exceed two trillion...

A cornerstone of physics may require a rethink if findings at the National Institute of Standards and Technology (NIST) are confirmed. Recent experiments suggest that the most rigorous predictions based on the fundamental theory of electromagnetism—one of the four fundamental forces in the universe, and harnessed in all electronic devices—may not accurately account for the behavior of atoms in exotic, highly charged states. The theory in question is known as quantum electrodynamics, or QED, which physicists have held in high regard for decades because of its excellent track record describing electromagnetism's effects on matter. In particular, QED has been especially...

The story begins with a letter from Albert Einstein to Franklin D. Roosevelt in 1939. The celebrated physicist warned the president that Nazi Germany was developing the makings of an atomic bomb. Roosevelt knew what would happen if Hitler got such a weapon. The president ordered a massive secret project to make sure the U.S. beat him to it. Scientists from all over the country were enlisted in the effort. Early in 1942 Enrico Fermi and a team of physicists gathered at the University of Chicago's Metallurgical Laboratory. Their goal was to develop a self-sustaining nuclear pile. This was the...

On December 2, 1942, 49 scientists, led by Enrico Fermi, made history when Chicago Pile 1 (CP-1) went critical and produced the world's first self-sustaining, controlled nuclear chain reaction.

Calling chemistry ‘molecular architecture’ is even more apt than it might seem. There was a time when architectural engineering was largely about getting buildings to stay up: to withstand the stresses and forces that act on them. But today’s architecture is responsive, mutable, adaptive and dynamic. Likewise, chemistry could appear in its first flush to be about making bonds that will last, but today’s chemistry is just as concerned with breaking as it is with making. The dynamic role of weak hydrogen bonding, for example, was illustrated with the discovery of DNA’s structure: to template replication and transcription, the molecule...

No hints of “new physics” beyond the predictions of the Standard Model have turned up in experiments at the Large Hadron Collider, a 17-mile circular tunnel at CERN Laboratory in Switzerland that slams protons together at high energies. (Photo: CERN) As a young theorist in Moscow in 1982, Mikhail Shifman became enthralled with an elegant new theory called supersymmetry that attempted to incorporate the known elementary particles into a more complete inventory of the universe.“My papers from that time really radiate enthusiasm,” said Shifman, now a 63-year-old professor at the University of Minnesota. Over the decades, he and thousands of...

A group of Penn State physicists says the universe we now see could have arisen from a "Big Bounce" rather than a Big Bang. The new work by Penn State, led by professor Abhay Ashtekar, director of the Institute for Gravitation and the Cosmos, proposes ways to apply quantum physics "further back in time than ever before – right back to the beginning," the university says in a release. We have a pretty good idea of the large-scale structures of the universe when it was only a few hundred thousand years old. That comes from studying the fingerprint of the...

A team at the Max Planck Institute for Astronomy has found the largest recorded black hole, one that swallows an unprecedented amount of its home galaxy, potentially requiring a rethink in our understanding of galactic formation. The huge hole has been spotted in the heart of the disk system NGC 1277, a smallish galaxy about 10 per cent of the size of the Milky Way and situated around 220 million light-years from Earth, in the constellation Perseus. Almost all galaxies have black holes at their centers, but they typically only take up around 0.1 per cent of the total galactic...

The first steps towards interstellar travel have been taken, but the stars are very far away. Voyager 1 is about 17 light-hours distant from Earth and is traveling with a velocity of 0.006 percent of light speed, meaning it will take about 17,000 years to travel one light-year. Fortunately, the elusive "warp drive" now appears to be evolving past difficulties with new theoretical advances and a NASA test rig under development to measure artificially generated warping of space-time. The warp drive broke away from being a wholly fictional concept in 1994, when physicist Miguel Alcubierre suggested that faster-than-light (FTL) travel...

Credit: CERN Still too soon to know. That's the latest word from particle physicists working with the world's largest atom smasher—Europe's Large Hadron Collider in Switzerland—as they try to figure out whether the particle they discovered in July is precisely the long-sought Higgs boson or something a tad different. The key question is whether the new particle decays into combinations of familiar particles at the rates that physicists' standard model predicts. So far, the measured decay rates generally match expectations, but the statistical uncertainties are too large to say anything conclusive, physicists working with the gargantuan particle detectors known...

Please remember that this app works only in Google Chrome Screenshot from 100,000 Stars Want to explore the Milky Way? A new visualization tool from Google called 100,000 Stars lets you take a tour of our cosmic neighborhood, and with a few clicks of your mouse you can zoom in, out and around and do a little learning along the way. Zoom in to learn the names of some of the closest stars; click on the names to find out more information about them. Playing with it is great fun, and I’ve been experimenting with it for a while. The...

Explanation: Could you tell the story of human existence in a minute? This thrilling video culls together multiple teasing snippets in an attempt to do just that. And sets it to music. Briefly depicted, from start to finish, is an artistic animation of the Big Bang, a trip across the early universe, the formation of the Earth and Moon, the emergence of multi-celled life and plants, the rise of reptiles and dinosaurs, a devastating meteor strike, the rise of mammals and humans, and finally the rise of modern civilization. The minute movie ends with a flyover of the modern skyscraper...

LONDON (Reuters) - An international team of astronomers has produced the first map of the universe as it was 11 billion years ago, filling a gap between the Big Bang and the rapid expansion that followed. The study, published in the journal Astronomy & Astrophysics, shows the universe went through a phase roughly three billion years after the Big Bang when expansion actually started to slow, before the force of so-called 'dark energy' kicked in and sent galaxies accelerating away from each other. Much is known about the immediate aftermath of the Big Bang from studies of its afterglow in...

It’s not only possible to get light to tie itself in knots: given the right conditions, it will do so spontaneously, according to a paper published last week in Nature. El Reg has no possible hope of fully understanding this paper (published in full, an emerging trend we welcome), but one really interesting idea is right there in the abstract: “We anticipate similar spontaneous knot topology to be a universal feature of waves whose phase front is twisted and nonlinearly modulated, including superfluids and trapped matter waves.” [Emphasis added] In other words, this research has the potential to be replicated...

(Phys.org)—David Ruffner and David Grier of New York University have developed a technique for using Bessel beams to draw a particle toward a source. In their paper published in Physical Review Letters they describe how they used their technique to pull 30 micrometer sized silica spheres suspended in water, towards a laser source. A device that uses energy to pull an object towards a source is known as a "tractor beam" after the fictional technology of Star Trek fame. To date no such device exists, but this new work by Ruffner and Grier shows that it might be possible. Their...

3D image shows ginormous filament of Big Bang batter Dark matter can't really be "seen" as such, it can only be detected by looking at the gravitational effects it has on the space around it. But by collating images from the Hubble Space telescope, the researchers now have a picture of dark matter (shown in blue above) extending 60 million light-years away from one of the most massive galaxy clusters astrophysicists know about – MACS J0717. Big Bang theories predict that when the universe was first created, dense matter condensed into a web of tangled dark matter filaments throughout the...

Forget Wimpy Plans and NIMBYs, Let's Solve the Energy Crisis by Blowing Up Mercury Posted by Derek_Mead on Wednesday, Apr 04, 2012 Save this post NextPrev Add This With all the squabbling about oil killing us all, climate change screwing with polar bears, nuclear plants falling apart, solar panels sucking on a cloudy day, and wind turbines scything through migratory birds with a gory violence best explained by an Omega Crom song, there’s a big point that all the complainers in the energy debate are ignoring: These days, we are being huge wimps. Millennia ago us humans were building...

•Political scientists from UCLA compare candidates based on 'competence' •Most students interpreted 'competence' as 'attractiveness' •Mitt Romney scored in the 99th percentile, Sarah Palin in the 95th and Paul Ryan in the 67th •'If the election were decided on looks, it would be no contest' Republican duo Mitt Romney and Paul Ryan are one of the hottest tickets this nation has ever seen, and now there's proof that its not just their politics. According to professors at the University of California, Mitt Romney scores in the 99th percentile of all politicians for his looks alone, far outpacing his running mate...

New theory describes faster than light travel, could explain CERN's results Some of the greatest physicists of the twentieth century, including Albert Einstein, consider the speed of light a sort of universal "speed limit".  But over the past couple decades physicists theorized that it should be possible to break this law and get away with it -- to travel faster than the speed of light. I. CERN Results Potentially Described One of several possible routes to faster-than-light travel was potentially demonstrated when researchers at CERN, the European physics organization known for maintaining the Large Hadron Collider, sent high-energy particles through the Earth's crust from Geneva, Switzerland...