A new analysis that refutes challenges to the existence of dark matter in certain galaxies appears in an article published this week in the journal Nature. Leading author of the article is Avishai Dekel, professor of physics at the Hebrew University of Jerusalem.
Accepted cosmological theory postulates that every observable galaxy in the universe (each made up of billions of stars similar to our sun) is embedded in a massive “halo” of dark matter. Though unseen, dark matter
In recent years, researchers have developed astonishing new insights into a hidden unity between the motion of objects in space and that of the smallest particles. It turns out there is an almost perfect parallel between the mathematics describing celestial mechanics and the mathematics governing some aspects of atomic physics. These insights have led to new ways to design space missions, as described in the article, “Ground Control to Niels Bohr: Exploring Outer Space with Atomic Physics”
Physicists who work with a concept called string theory envision our universe as an eerie place with at least nine spatial dimensions, six of them hidden from us, perhaps curled up in some way so they are undetectable. The big question is why we experience the universe in only three spatial dimensions instead of four, or six, or nine.
Two theoretical researchers from the University of Washington and Harvard University think they might have found the answer. They believe the way o
ESO’s VLT Captures Image of Spiral Galaxy NGC 1350
Eighty-five million years ago on small planet Earth, dinosaurs ruled, ignorant of their soon-to-come demise in the great Jurassic extinction, while mammals were still small and shy creatures. The southern Andes of Bolivia, Chile, and Argentina were not yet formed and South America was still an island continent.
Eighty-five million years ago, our Sun and its solar system was 60,000 light years away from where it now
Molecular electronics is the ultimate miniaturization of electronics. In this area of research, scientists have been studying the movement of electrons through individual molecules in an effort to understand how they might control and use the process in new technologies. Computers and thousands of other devices could become vastly faster, smaller and more reliable than conventional transistor-based (wire-based) electronics.
A team of Ohio University and Brazilian physicists has tak
The UK’s first engineering feasibility study into missions for deflecting asteroids has begun.
The Engineering and Physical Sciences Research Council (EPSRC) is funding a new three-year study into interception and deflection strategies for asteroids found to be on a collision course with Earth. Although there have been similar studies in the past, Dr Gianmarco Radice, department of Aerospace Engineering, University of Glasgow, and Professor Colin McInnes, department of Mechanical E
At a ceremony last night at CERN*, Mr W. Cleon Anderson, President of the Institute of Electrical and Electronics Engineers (IEEE**) formally dedicated a Milestone plaque in recognition of the invention of electronic particle detectors at CERN. The plaque was unveiled by Mr Anderson and Georges Charpak, the Nobel-prize winning inventor of wire chamber technology at CERN in 1968.
With the attribution of this IEEE Milestone, CERN finds itself in good company. There are currently over 60 Mil
It seemed like science-fiction just a few years ago, but is now common practice for scientists at the Paul Drude Institute for Solid State Electronics (PDI) in Berlin. The scientists manipulate single atoms resting on surfaces and assemble them into wires or tiny clusters. In the world of nanometric dimensions, fundamental material properties such as magnetism, electrical conductivity or chemical reactivity differ from the conventional behaviour observed in everyday life. If metal clusters or s
Physicists usually describe the world from the vantage point of its smallest component parts. But quantum theory does not allow itself to be conceptually crammed into such a framework. Instead, in her dissertation at Uppsala University in Sweden, Barbara Piechocinska takes her point of departure in the mathematics of the dynamic whole and finds that time thereby takes on new meaning. Throughout the centuries reductionist philosophy has reigned supreme in physics. It has been assumed that it
The NASA/ESA Hubble Space Telescope and NASA’s Spitzer Space Telescope have teamed up to ’weigh’ the stars in distant galaxies. One of these galaxies is not only one of the most distant ever seen, but it appears to be unusually massive and mature for its place in the young Universe.
This has surprised astronomers because the earliest galaxies in the Universe are commonly thought to have been much smaller agglomerations of stars that gradually merged together later to bu
Based on the recommendations of asteroid experts, ESA has selected two target asteroids for its Near-Earth Object deflecting mission, Don Quijote.
Don Quijote is an asteroid-deflecting mission currently under study by ESA’s Advanced Concepts Team (ACT). Earlier this year the NEO Mission Advisory Panel (NEOMAP), consisting of well-known experts in the field, delivered to ESA a target selection report for Europe’s future asteroid mitigation missions, identifying the relevant criter
Researchers at the University of Illinois at Urbana-Champaign have demonstrated the room-temperature operation of a heterojunction bipolar transistor laser, moving it an important step closer to commercialization. The scientists describe their work in the Sept. 26 issue of the journal Applied Physics Letters.
“We have shown that the transistor laser, even in its early state of development, is capable of room-temperature operation at a speed of 3 gigahertz,” said Nick Holonya
Moving one step at a time, newly designed molecule walks in a straight line; potential applications in molecular computing
A research team, led by UC Riverside’s Ludwig Bartels, is the first to design a molecule that can move in a straight line on a flat surface. It achieves this by closely mimicking human walking. The “nano-walker” offers a new approach for storing large amounts of information on a tiny chip and demonstrates that concepts from the world we live in can be dupli
Sub-millimetre APEX telescope inaugurated at Chajnantor
The Atacama Pathfinder Experiment (APEX) project celebrates the inauguration of its outstanding 12-m telescope, located on the 5100 m high Chajnantor plateau in the Atacama Desert (Chile). The APEX telescope, designed to work at sub-millimetre wavelengths, in the 0.2 to 1.5 mm range, passed successfully its Science Verification phase in July, and since then is performing regular science observations. This new front-line fac
Astronomers have found compelling evidence that a supernova shock wave has produced a large amount of cosmic rays, particles of mysterious origin that constantly bombard the Earth. This discovery, made with NASA’s Chandra X-ray Observatory, supports theoretical arguments that shock waves from stellar explosions may be a primary source of cosmic rays.
This finding is important for understanding the origin of cosmic rays, which are atomic nuclei that strike the Earth’s atmospher
University of Arizona physicists have directly measured how close speeding atoms can come to a surface before the atoms’ wavelengths change.
Theirs is a first, fundamental measurement that confirms the idea that the wave of a fast-moving atom shortens and lengthens depending on its distance from a surface, an idea first proposed by pioneering quantum physicists in the late 1920s.
The measurement tells nanotechnologists how small they can make extremely tiny devices bef
Feedback
