2019 Spring Graduate Colloquium Series: Wencong Gan/Hao Zhu

DateMarch 8, 2019Time3:35 - 5:00 pm
LocationBaylor Sciences Building, Room E.125
2019 Spring Graduate Colloquium Series

Wencong Gan

Distinguishing Black Hole Microstates using Holevo Information

We use Holevo information in the two-dimensional conformal field theory (CFT) with a large central charge c to distinguish microstates from the underlying thermal state. Holographically, the CFT microstates of a thermal state are dual to black hole microstate geometries in anti–de Sitter space. It was found recently that holographic Holevo information shows plateau behaviors at both short and long interval regions. This indicates that the black hole microstates are indistinguishable from the thermal state by measuring over a small region, and perfectly distinguishable over a region with its size comparable to the whole system. In this Letter, we demonstrate that the plateaus are lifted by including the 1/c corrections from both the vacuum and nonvacuum conformal families of CFT in either the canonical ensemble or microcanonical ensemble thermal state. Our results imply that the aforementioned indistinguishability and distinguishability of black hole microstate geometries from the underlying black hole are spoiled by higher order Newton constant G_N corrections of quantum gravity.

[1] Guo W, Lin F L, Zhang J. Distinguishing black hole microstates using Holevo information[J]. Physical review letters, 2018, 121(25): 251603.

Hao Zhu

Against Waste: Transform metallized paper into nanorod and nanoparticle directly

We create wasted metalized paper all the day: look at the aluminum can in trash bin , we could not estimate how many waste would be created in one day. In this work, for the first-time, the thermal micronizing technique has been used to directly transform the metallized paper wastes to Al-Si nanorod and Al nanoparticles. Using FT-IR analysis and first-principle plane-wave calculation, this paper investigated metallized paper’s structure and modified it to directly transform this waste into nanomaterials by thermal micronizing technique. Structure of nanoparticles and nanorods has been investigated using SEM, TEM, and XPS analysis which showed that two main Al-Si nanorod and Al nanoparticle morphologies created as a result of the different surface tensions, facilitating their separation by Eddy current separation technique.

[1] Zahra Karbalaei Mirza Shahrbabaki, Farshid Pahlevani, Narjes Gorjizadeh. Direct Transformation of Metallized Paper into Al-Si Nano-Rod and Al Nano-Particles Using Thermal Micronizing Technique. Materials 2018, 11, 1964; doi:10.3390/ma11101964

For more information contact: Dr. Kenneth Park, 254-710-2282
PublisherDepartment of Physics
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