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Updated: Jun 5, 2025

A Microfluidic-based Hydrodynamic Trap for Single Particles
Published on: January 21, 2011
Marginally outer trapped tubes in de Sitter spacetime
Marc Mars1, Carl Rossdeutscher2, Walter Simon2
1Departamento de Física Fundamental, Universidad de Salamanca, Plaza de la Merced s/n, 37008 Salamanca, Spain.
We show that all marginally outer trapped surfaces (MOTSs) in de Sitter spacetime are unstable. However, we prove the existence of complete MOTTs with constant mean curvature sections in de Sitter spacetime.
Area of Science:
- General Relativity
- Differential Geometry
- Mathematical Physics
Background:
- Marginally outer trapped surfaces (MOTSs) are crucial for defining black hole horizons.
- Constructing marginally outer trapped tubes (MOTTs) in de Sitter spacetime presents unique challenges.
- Previous work established existence of CMC surfaces in spheres, relevant for MOTT construction.
Purpose of the Study:
- To investigate the properties of MOTSs in de Sitter spacetime.
- To prove the existence of complete MOTTs with constant mean curvature (CMC) sections in de Sitter spacetime.
- To analyze the stability of MOTSs and their implications for MOTTs.
Main Methods:
- Analysis of spacetimes satisfying the null convergence condition and possessing a timelike conformal Killing vector.
- Application of a scaling argument to translate results from spherical geometry to de Sitter spacetime.
- Comparison with existing area laws for holographic screens.
Main Results:
- Demonstrated that all MOTSs in spacetimes with specific conditions are unstable.
- Proved the existence of complete MOTTs with CMC sections in de Sitter spacetime.
- Showed that the area of these CMC sections strictly increases monotonically.
Conclusions:
- The instability of MOTSs prevents standard propagation results from applying to MOTTs.
- The existence of complete MOTTs with CMC sections in de Sitter spacetime is established.
- The monotonic increase in CMC section area offers insights into holographic screen properties.
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