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Calendar of Physics Talks Vienna
| Wheeler DeWitt States and their Holographic Interpretation |
| Speaker: | Matthew Blacker (University of Cambridge) |
| Abstract: | In the canonical quantization of gravity, the Hamiltonian constraint of general relativity is promoted to the Wheeler DeWitt (WDW) equation â the quantum cosmological analogue of the Schrödinger equation. Solving the WDW equation is challenging, but by assuming homogeneity and isotropy we can construct WDW states via theHamilton-Jacobi formalism of classical mechanics. Such an approach lends itself towards a holographic interpretation, as the Hamilton-Jacobi equation also describes the
holographic renormalization group flow. The first technical point of this talk is to construct a semiclassical wavefunction (in 3+1 dimensional pure gravity with a positive cosmological constant) which
strongly localises on the de-Sitter Schwarzschild spacetime. The second aim is to conjecture a holographic duality between these WDW states and a family of quantum theories ... [2406.02508] |
| Date: | Thu, 22.08.2024 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | SEM 136, Freihaus, TU Wien, Wiedner Hauptstr. 8-10, 1040 Vienna (10th floor) |
| Contact: | Daniel Grumiller |
| Exploring Ion Scattering, Electronic Excitations and Straggling for Advanced Understanding of Materials |
| Speaker: | Pedro Luis Grande (Federal University of Rio Grande do Sul/Brazil) |
| Abstract: | This presentation explores scattering analysis, stopping, and straggling to deepen our understanding of ion interactions with matter, which is potentially relevant to a wide array of fields, spanning from nuclear physics to material science and particle therapy. Ion scattering with hydrogen (H) and helium (He) at 100-200 keV enables the analysis of advanced materials at a nanometer scale. In particular, the examination of nanoparticles (NPs) will be emphasized. Stopping power, which measures the energy loss by charged particles, is crucial for predicting particle behavior in ion beam analysis. We discuss various models, ranging from ab initio calculations to simpler ones, that can accurately predict stopping power. Moreover, straggling, the statistical spread of energy loss, presents challenges in precise particle beam applications and offers insights into more complex energy loss proces |
| Date: | Fri, 23.08.2024 |
| Time: | 10:00 |
| Location: | TU Wien, Institut für Angewandte Physik, E134 1040 Wien, Wiedner HauptstraÃe 8-10 Yellow Tower âBâ, 5th floor, SEM.R. DB gelb 05 B |
| Contact: | Univ.Prof. Dr. Richard WILHELM |
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