We argue that the confined and deconfined phases in gauge theories are connected by a partially deconfined phase (i.e. SU(M ) in SU(N ), where M < N , is deconfined), which can be stable or unstable depending on the details of the theory. When this phase is unstable, it is the gauge theory counterpart of the small black hole phase in the dual string theory. Partial deconfinement is closely related to the Gross-Witten-Wadia transition, and is likely to be relevant to the QCD phase transition.The mechanism of partial deconfinement is related to a generic property of a class of systems. As an instructive example, we demonstrate the similarity between the Yang-Mills theory/string theory and a mathematical model of the collective behavior of ants [Beekman et al., Proceedings of the National Academy of Sciences, 2001]. By identifying the D-brane, open string and black hole with the ant, pheromone and ant trail, the dynamics of two systems closely resemble with each other, and qualitatively the same phase structures are obtained.

We study the confinement/deconfinement transition in the D0-brane matrix model (often called the BFSS matrix model) and its one-parameter deformation (the BMN matrix model) numerically by lattice Monte Carlo simulations. Our results confirm general expectations from the dual string/M-theory picture for strong coupling. In particular, we observe the confined phase in the BFSS matrix model, which is a nontrivial consequence of the M-theory picture. We suggest that these models provide us with an ideal framework to study the Schwarzschild black hole, M-theory, and furthermore, the parameter region of the phase transition between type IIA superstring theory and M-theory. A detailed study of M-theory via lattice Monte Carlo simulations of the D0-brane matrix model might be doable with much smaller computational resources than previously expected.

An ultrawideband (UWB) radar-based breast cancer detection system, which is composed of complementary metal-oxide-semiconductor integrated circuits, is presented. This system includes Gaussian monocycle pulse (GMP) generation circuits, switching (SW) matrix circuits, equivalent-time sampling circuits, and a compact UWB antenna array. During the detection process, the GMP signal with the center frequency of 6 GHz is first generated and transmitted with a repetition frequency of 100 MHz. The GMP signal is sent to a selected transmitter antenna by the SW matrix module, and the reflected signal is captured by the receiver antennas. Next, the high-speed equivalent-time sampling circuits are employed to retrieve the reflected GMP signal. A confocal algorithm is used to reconstruct the breast image. The total size for the prototype module is 45 cm × 30 cm × 14.5 cm in length, width, and height, respectively, which is dramatically smaller than the conventional detection systems. Using our proposed system, we demonstrate a successful detection of 1-cm cancer target in the breast phantom.INDEX TERMS Breast cancer, CMOS, microwave imaging, ultrawideband, confocal algorithm.

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LHCf is an experiment dedicated to the measurement of neutral particles emitted in the very forward region of LHC collisions. The physics goal is to provide data for calibrating the hadron interaction models that are used in the study of Extremely High-Energy Cosmic-Rays. This is possible since the laboratory equivalent collision energy of LHC is 10 17 eV. Two LHCf detectors, consisting of imaging calorimeters made of tungsten plates, plastic scintillator and position sensitive sensors, are installed at zero degree collision angle ±140 m from an interaction point (IP). Although the lateral dimensions of these calorimeters are very compact, ranging from 20 mm×20 mm to 40 mm×40 mm, the energy resolution is expected to be better than 6% and the position resolution better than 0.2 mm for γ-rays with energy from 100 GeV to 7 TeV. This has been confirmed by test beam results at the CERN SPS. These calorimeters can measure particles emitted in the pseudo rapidity range η>8.4. Detectors, data acquisition and electronics are optimized to operate during the early phase of the LHC commissioning with luminosity below 10 30 cm −2 s −1 . LHCf is expected to obtain data to compare with the major hadron interaction models within a week or so of operation at luminosity ∼ 10 29 cm −2 s −1 . After ∼10 days of operation at luminosity ∼10 29 cm −2 s −1 , the light output of the plastic scintillators is expected to degrade by ∼10% due to radiation damage. This degradation will be monitored and corrected for using calibration pulses from a laser.