1,093 research outputs found
Thermodynamics of Fuzzy Spheres in PP-wave Matrix Model
We discuss thermodynamics of fuzzy spheres in a matrix model on a pp-wave
background. The exact free energy in the fuzzy sphere vacuum is computed in the
\mu -> \infty limit for an arbitrary matrix size N. The trivial vacuum
dominates the fuzzy sphere vacuum at low temperature while the fuzzy sphere
vacuum is more stable than the trivial vacuum at sufficiently high temperature.
Our result supports that the fluctuations around the trivial vacuum would
condense to form an irreducible fuzzy sphere above a certain temperature.Comment: 18 pages, 4 figures, LaTeX2
Membrane Fuzzy Sphere Dynamics in Plane-Wave Matrix Model
In plane-wave matrix model, the membrane fuzzy sphere extended in the SO(3)
symmetric space is allowed to have periodic motion on a sub-plane in the SO(6)
symmetric space. We consider a background configuration composed of two such
fuzzy spheres moving on the same sub-plane and the one-loop quantum corrections
to it. The one-loop effective action describing the fuzzy sphere interaction is
computed up to the sub-leading order in the limit that the mean distance
between two fuzzy spheres is very large. We show that the leading order
interaction is of the 1/r^7 type and thus the membrane fuzzy spheres
interpreted as giant gravitons really behave as gravitons.Comment: 28 pages, LaTeX2e, 1 figure, 1 tabl
Thermodynamic Behavior of Fuzzy Membranes in PP-Wave Matrix Model
We discuss a two-body interaction of membrane fuzzy spheres in a pp-wave
matrix model at finite temperature by considering a fuzzy sphere rotates with a
constant radius r around the other one sitting at the origin in the SO(6)
symmetric space. This system of two fuzzy spheres is supersymmetric at zero
temperature and there is no interaction between them. Once the system is
coupled to the heat bath, supersymmetries are completely broken and non-trivial
interaction appears. We numerically show that the potential between fuzzy
spheres is attractive and so the rotating fuzzy sphere tends to fall into the
origin. The analytic formula of the free energy is also evaluated in the large
N limit. It is well approximated by a polylog-function.Comment: 13 pages, 4 figures, LaTe
Glacier dynamics near the calving front of Bowdoin Glacier, northwestern Greenland
To better understand recent rapid recession of marine-terminating glaciers in Greenland, we performed satellite and field observations near the calving front of Bowdoin Glacier, a 3 km wide outlet glacier in northwestern Greenland. Satellite data revealed a clear transition to a rapidly retreating phase in 2008 from a relatively stable glacier condition that lasted for >20 years. Ice radar measurements showed that the glacier front is grounded, but very close to the floating condition. These results, in combination with the results of ocean depth soundings, suggest bed geometry in front of the glacier is the primary control on the rate and pattern of recent rapid retreat. Presumably, glacier thinning due to atmospheric and/or ocean warming triggered the initial retreat. In situ measurements showed complex short-term ice speed variations, which were correlated with air temperature, precipitation and ocean tides. Ice speed quickly responded to temperature rise and a heavy rain event, indicating rapid drainage of surface water to the bed. Semi-diurnal speed peaks coincided with low tides, suggesting the major role of the hydrostatic pressure acting on the calving face in the force balance. These observations demonstrate that the dynamics of Bowdoin Glacier are sensitive to small perturbations occurring near the calving front
Borehole video observation of Langhovde Glacier, Antarctica
第3回極域科学シンポジウム 横断セッション「海・陸・氷床から探る後期新生代の南極寒冷圏環境変動」11月27日(火) 国立国語研究所 2階講
The change of terminus and ice velocity field and grounding line estimation in Langhovde Glacier, Antarctica.
第3回極域科学シンポジウム 横断セッション「海・陸・氷床から探る後期新生代の南極寒冷圏環境変動」11月27日(火) 国立国語研究所 2階講
Hot water drilling and measurements beneath the grounding zone of Langhovde Glacier, East Antarctica
第3回極域科学シンポジウム 横断セッション「海・陸・氷床から探る後期新生代の南極寒冷圏環境変動」11月27日(火) 国立国語研究所 2階講
Modeling the flow dynamics of Bowdoin Glacier, Qaanaaq region, northwestern Greenland
第6回極域科学シンポジウム分野横断セッション:[IA] 急変する北極気候システム及びその全球的な影響の総合的解明―GRENE北極気候変動研究事業研究成果報告2015―11月19日(木) 国立極地研究所 2階 大会議
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