The Mars Desert Research Station is near Hanksville UT in badlands in the Morrison Formation. The large structure is the Hab. The Musk observatory is to the right, the GreenHab to the left. Researchers come from all over the world to do simulations relative to the exploration of Mars. BYU students are doing a number of projects and support the projects of other groups.
This photo shows a sideview of an intense laser pulse producing a 4-cm long streak of plasma in a helium-filled glass tube. The laser punches through a foil at the end of the tube, which separates the helium from an evacuated region. The group of Dr. Justin Peatross investigates beams of high-order harmonics produced in this interaction.
The widely accepted intuition that the important properties of solids are determined by a few key variables underpins many methods in physics. Though this reductionist paradigm is applicable in many physical problems, its utility can be limited because the intuition for identifying the key variables often does not exist or is difficult to develop. We have developed a simple, general, and efficient way of finding the key descriptive variables using mathematics that has revolutionized image and signal processing. The key idea is to imagine physics as a "signal" provided by Mother Nature and to use compressive sensing (CS) to recover that signal. Compressive sensing is a powerful paradigm for model building; we find that its models are more physical and predict more accurately than current state-of-the-art approaches and can be constructed at a fraction of the computational cost and user effort.
Experimentally and computationally, the structure of Pt–Cu at 1:3 stoichiometry has a convoluted history. The L1_3 structure has been predicted to occur in binary alloy systems, but has not been linked to experimental observations. Using a combination of electron diffraction, synchrotron X-ray powder diffraction, and Monte Carlo simulations, we found that this phase is present in the Cu–Pt system at 1:3 stoichiometry. We also find that the 4-atom, fcc superstructure L13 is equivalent to the large 32-atom orthorhombic superstructure reported in older literature, resolving much of the confusion surrounding this composition. Monte Carlo simulations confirm the formation of a large cubic superstructure at high temperatures, and its eventual transformation to the L1_3 structure at lower temperature, but also provide evidence of other transitional orderings.
Every technology is intimately related to a particular materials set. The steam engines that powered the industrial revolution in the eighteenth century were made of steel and, information and communication technologies are underpinned by silicon. Once a material is chosen for a given technology, it gets locked with it because of the investments associated with establishing large-scale production lines. This means that changing the materials set in an established technology is a rare event and must be considered as a revolution. Computational materials discovery can play an important role in fueling such revolutions
Kent Gee and Traci Neilsen et al. recently published an article titled "On the crest factor of noise in full-scale supersonic jet engine measurements " in Proceedings of Meetings on Acoustics. Click on the image above to read it.
Tetons and Snake River, Planet Earth : An alluring night skyscape, this scene looks west across the Grand Teton National Park, Wyoming, USA, Planet Earth. The Snake River glides through the foreground, while above the Tetons' rugged mountain peaks the starry sky is laced with exceptionally strong red and green airglow....
This photograph and Description come from NASA's Astronomy Picture of the Day web site.