Session J23: Invited Session: Industrial Physics Forum: Frontiers of Physics

Probing the Last 13.8 Billion Years in the Universe with the Atacama Cosmology Telescope

The Atacama Cosmology Telescope (ACT) is a 6 m special purpose telescope designed to measure the cosmic microwave background (CMB) at millimeter wavelengths. ACT has an angular resolution of better than 1.4', which means it measures not only the primordial fluctuations in the CMB, but is also sensitive to the intervening universe in several ways. ACT observes from a site at 5300 m in the Atacama Desert in Chile. This midlatitude site allows ACT to map regions of the sky in which there exist substantial data from surveys at other wavelengths. ACT detects clusters of galaxies through their Sunyaev-Zeldovich effect (a spectral effect due to scattering off the hot electrons in the clusters). ACT measures clusters directly, in blind surveys, and also makes statistical measurements based on stacking analyses and by measuring the 3-point function in the maps. Furthermore, gravitational lensing by all the intervening matter from the primordial epoch to now leads to signatures in the 4-point functions in the ACT maps. Cross-correlating the ACT lensing deflection field with other optical surveys in the same region is a particularly fruitful way of deriving cosmological information on the expansion history of the universe.   

Power blackouts, sudden death, and flash crashes: The physics of interdependent networks

Recent disasters ranging from abrupt financial ``flash crashes'' and large-scale power outages to sudden death among the elderly dramatically exemplify the fact that the most dangerous vulnerability is hiding in the many interdependencies among different networks. This talk reports recent work quantifying failure mechanisms in interconnected networks, and demonstrates the need to consider mutually dependent network properties in designing resilient systems. Specifically, we have uncovered new laws governing the nature of switching phenomena in coupled networks, and found that phenomena that are continuous ``second order'' phase transitions in isolated networks become discontinuous abrupt ``first order'' transitions in interdependent networks [J. Gao, S. V. Buldyrev, H. E. Stanley, and S. Havlin, ``Novel Behavior of Networks Formed from Interdependent Networks,'' Nature Physics {\bf 8}, 40 (2012)]. We also report parallel efforts to understand the phenomenon of spontaneous recovery in dynamical networks as occurs, e.g., immediately after a flash crash [A. Majdandzic, B. Podobnik, S. V. Buldyrev, D. Y. Kenett, S. Havlin, and H. E. Stanley, ``Spontaneous Recovery in Dynamic Networks,'' Nature Physics {\bf 9}, No. 1 (2014)].   

Exploring the Habitability Potential of Mars with Mars Science Laboratory

Curiosity has been roving Gale Crater since landing on Mars August 5, 2013. The investigations that comprise the Mars Science Laboratory payload have interrogated the environment in as comprehensive an approach as has ever been attempted on the surface of another planet, using a variety of approaches to characterize both the surface materials and the atmosphere. This talk will summarize the Curiosity's progress at Gale Crater.   

Cryogenic Semiconductor Detectors in Search of Dark Matter

Dark Matter dominates the matter content in the Universe and is believed to be made up of Weakly Interacting Massive Particles (WIMP) that rarely interact with ordinary matter. Cryogenic Dark Matter Search (CDMS) has been a leader among more than 30 experiments worldwide, which are attempting to detect tiny vibrations from the recoil of WIMPs in terrestrial detectors. It uses sophisticated photo-lithographically patterned cryogenically cooled large mass Germanium and Silicon. Help from the semiconductor industry has been crucial in reducing the cost 20 fold from half-million/kg, while simultaneously improving the quality and throughput of fabrication, essential for large ton-scale experiments capable of making such a discovery possible.   

The Physics of Cosmic Rays

Cosmic rays, mostly relativistic protons, comprise one billionth of interstellar particles by number, but have as much energy as the rest of the interstellar gas combined. They are probably accelerated in supernova remnants, and are confined to the Galaxy by the interstellar magnetic field. Through interacting with the field, they exchange energy and momentum with the interstellar gas, driving magnetic turbulence and outflows, and generating significant heat. An even smaller minority of cosmic rays, those with the highest energies, probably originate outside the Galaxy, and challenge all existing theories of how they are accelerated.