Physics limits information processing, and hence the possible forms of intelligent beings and
their civilizations. In this review I discuss physical limitations on density, speed, size, energy …

Interacting theories with higher-derivatives involve ghosts. They correspond to instabilities
that display themselves at the classical level. We notice that comparatively “benign” …

The General Theory of Relativity has been an extremely successful theory, with a well
established experimental footing, at least for weak gravitational fields. Its predictions range …

We discuss supersymmetry breaking via 3-form fluxes in chiral supersymmetric type IIB
orientifold vacua with D3-and D7-branes. After a general discussion of possible choices of …

There are various arguments for the metaphysical impossibility of time travel. Is it impossible
because objects could then be in two places at once? Or is it impossible because some …

Ghost-free higher-derivative theory - ScienceDirect Skip to main contentSkip to article Elsevier
logo Journals & Books Search RegisterSign in View PDF Download full issue Search …

The idea of chronology protection gained considerable currency during the 1990s when it
became clear that traversable wormholes, which are not too objectionable in their own right …

In the present paper we discuss properties of a model of a ring wormhole, recently proposed
by Gibbons and Volkov [Phys. Rev. D 96, 024053 (2017) PRVDAQ 2470-0010 …

A computer which has access to a closed timelike curve, and can thereby send the results of
calculations into its own past, can exploit this to solve difficult computational problems …

Книга посвящена проблемам теории времени. В основе исследования представление о
пространстве-времени как об абсолютном Мире событий. Распространенное …