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Showing posts from February, 2016
We live in a universe dominated by unseen matter, and on the largest scales, galaxies and everything they contain are concentrated into filaments that stretch around the edge of enormous voids. Thought to be almost empty until now, a group of astronomers based in Austria, Germany and the United States now believe these dark holes could contain as much as 20% of the 'normal' matter in the cosmos and that galaxies make up only 1/500th of the volume of the universe. The team, led by Dr Markus Haider of the Institute of Astro- and Particle Physics at the University of Innsbruck in Austria, publish their results in a new paper in Monthly Notices of the Royal Astronomical Society. Looking at cosmic microwave radiation, modern satellite observatories like COBE, WMAP and Planck have gradually refined our understanding of the composition of the universe, and the most recent measurements suggest it consists of 4.9% 'normal' matter (i.e. the matter that makes up sta…
Scientists on the DZero collaboration at the U.S. Department of Energy's Fermilab have discovered a new particle -- the latest member to be added to the exotic species of particle known as tetraquarks. Quarks are point-like particles that typically come in packages of two or three, the most familiar of which are the proton and neutron (each is made of three quarks). There are six types, or "flavors," of quark to choose from: up, down, strange, charm, bottom and top. Each of these also has an antimatter counterpart.
Over the last 60 years, scientists have observed hundreds of combinations of quark duos and trios.
In 2008 scientists on the Belle experiment in Japan reported the first evidence of quarks hanging out as a foursome, forming a tetraquark. Since then physicists have glimpsed a handful of different tetraquark candidates, including now the recent discovery by DZero -- the first observed to contain four different quark flavors.
DZero is one of two ex…
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Scientists have successfully simulated a black hole shaped like a very thin ring, which gives rise to a series of 'bulges' connected by strings that become thinner over time. These strings eventually become so thin that they pinch off into a series of miniature black holes, similar to how a thin stream of water from a tap breaks up into droplets. Credit: Pau Figueras, Markus Kunesch, and Saran Tunyasuvunakool; Image courtesy of University of Cambridge Researchers have shown how a bizarrely shaped black hole could cause Einstein's general theory of relativity, a foundation of modern physics, to break down. However, such an object could only exist in a universe with five or more dimensions. The researchers, from the University of Cambridge and Queen Mary University of London, have successfully simulated a black hole shaped like a very thin ring, which gives rise to a series of 'bulges' connected by strings that become thinner over time. These strings even…
A team of quantum physicists at Aalto University led by Dr. Sorin Paraoanu managed to tame a so-called "dark state," created in a superconducting qubit. A superconducting qubit is an artificial atom fabricated on a silicon chip as an electrical circuit made of capacitors and tunnel junctions. This technology is one of the most promising for the realization of quantum computers.
In the experiment, the circuit was operated in a regime where it no longer absorbs or emits electromagnetic waves of certain frequency, as if it would be hiding under an invisibility cloak -- hence the term "dark state." Then, by using a sequence of carefully-crafted microwave pulses, the team employed the dark state to realize a transfer of population from the ground energy level to the second energy level, without populating the first energy level. The amount of energy transferred in this process corresponds to a single microwave photon with about the same frequency as those …

Professor Brian Greene answers everything you wanted to know about string theory and the multiverse

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Professor Brian Greene answers everything you wanted to know about string theory and the multiverseLateline
Media player: "Space" to play, "M" to mute, "left" and "right" to seek. VIDEO: Interview: Brian Greene, Professor of Physics and Mathematics at Columbia University (Lateline)
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In December 2015, the United Nations passed a resolution to recognise on February 11 each year women's contributions to the field. The UN's research showed females "continued to be excluded from participating fully in science", with the number of science graduates significantly lower than males. That doesn't mean women have not excelled in science — far from it. The ABC spoke to a number of Australian female scientists and researchers at the top of their field. Michelle Simmons Michelle Simmons has been tasked with creating the next supercomputer that could change the face of international business, weather forecasting and drug design. While traditional computers complete calculations in sequential order, the quantum computer will complete the tasks simultaneously, potentially resulting in a device millions of times faster. Right now, the quantum physicist is busy assembling her team at the University of New South Wales, having recently being granted $46 million…
Sometimes a major discovery - like finding evidence to support the theory of dark matter - just requires a bit of creative thinking over a curry, as Dr Karl explains. When professional astronomers design new telescopes, it takes forests of paperwork, big buckeroonies (tens of millions of dollars minimum), and at least a decade. But hoorah for lateral thinking and hobbies. An astronomer's interest in nature photography led him to a radical new telescope very quickly and cheaply - and also got us one step closer to solving the mystery of how galaxies spring into existence. One top theory of how galaxies form involves dark matter. Way, way back, over 13 billion years ago, just a few thousand years after the big bang, practically all the mass in the universe was this mysterious dark matter. The dark matter began to clump together, thanks to gravity, and began to shape itself into roughly spherical objects - which began to collapse inwards. Various gases (such as hydrogen and helium) c…

What Are Gravitational Waves And Why Do They Matter?

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What Are Gravitational Waves And Why Do They Matter? If we detect them, it could mean a lot about the universe BySophie Bushwick



NASA/C. Henze Simulation of Gravitational Waves NASA researchers simulated the gravitational waves that would be produced when two black holes merged. Physicists have been buzzing (or rather, tweeting) about the possibility that the Laser Interferometer Gravitational-Wave Observatory (LIGO) experiment finally discovered gravitational waves. LIGO has been searching for these cosmic ripples for over a decade. Last September, it upgraded to Advanced-LIGO, a more sensitive system that's also better at filtering out noise. Advanced-LIGO has a much stronger chance of collecting concrete evidence of gravitational waves—if it hasn't already.
Scientists may be excited, but talk of gravitational waves leaves most people scratching their heads. What are these cosmic vibrations, and why are they making waves in the scientific community?
What are gravita…