Zobrazeno 1 - 10
of 297
pro vyhledávání: '"Leonhardt, Ulf"'
Autor:
Landau, Ziv, Leonhardt, Ulf
An observer at rest with the expanding universe experiences some extra noise in the quantum vacuum, and so does an accelerated observer in a vacuum at rest (in Minkowski space). The literature mainly focuses on the ideal cases of exponential expansio
Externí odkaz:
http://arxiv.org/abs/2406.09339
Publikováno v:
J. Opt. Soc. Am. B 41, 2122 (2024)
The interaction of quantum light with matter is of great importance to a wide range of scientific disciplines, ranging from optomechanics to high precision measurements. A central issue we discuss here, is how to make optimal use of both the spatial
Externí odkaz:
http://arxiv.org/abs/2403.03766
Autor:
Leonhardt, Ulf
Publikováno v:
J. Phys. A 56, 024001 (2023)
Wave noise is correlated. While it may look random in space, correlations appear in space-time, because the noise is carried by wave propagation. These correlations of wave noise give rise to fluctuation forces such as the Casimir force, they are res
Externí odkaz:
http://arxiv.org/abs/2301.03795
Autor:
Leonhardt, Ulf
In 1998 astronomers discovered that the expansion of the universe is accelerating. Somehow, something must have made gravity repulsive on cosmological scales. This something was called dark energy; it is described by Einstein's cosmological constant;
Externí odkaz:
http://arxiv.org/abs/2202.03862
Publikováno v:
Phys. Rev. Lett. 128, 183901 (2022)
Coordinate transformations are a versatile tool to mould the flow of light, enabling a host of astonishing phenomena such as optical cloaking with metamaterials. Moving away from the usual restriction that links isotropic materials with conformal tra
Externí odkaz:
http://arxiv.org/abs/2112.01420
Autor:
Efrat, Itai Y., Leonhardt, Ulf
Publikováno v:
Phys. Rev. B 104, 235432 (2021)
In inhomogeneous dielectric media the divergence of the electromagnetic stress is related to the gradients of \varepsilon and \mu, which is a consequence of Maxwell's equations. Investigating spherically symmetric media we show that this seemingly un
Externí odkaz:
http://arxiv.org/abs/2109.08092
Autor:
Leonhardt, Ulf
Publikováno v:
Europhys. Lett. 135, 10002 (2021)
Gibbons and Hawking [Phys. Rev. D 15, 2738 (1977)] have shown that the horizon of de Sitter space emits radiation in the same way as the event horizon of the black hole. But actual cosmological horizons are not event horizons, except in de Sitter spa
Externí odkaz:
http://arxiv.org/abs/2011.09930