Superluminal censorship
نویسندگان
چکیده
منابع مشابه
Perturbative superluminal censorship and the null energy condition
We argue that “effective” superluminal travel, potentially caused by the tipping over of light cones in Einstein gravity, is always associated with violations of the null energy condition (NEC). This is most easily seen by working perturbatively around Minkowski spacetime, where we use linearized Einstein gravity to show that the NEC forces the light cones to contract (narrow). Given the NEC, t...
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We propose and defend a distinction between two types of self-censorship: public and private. In public self-censorship, individuals restrain their expressive attitudes in response to public censors. In private self-censorship, individuals do so in the absence of public censorship. We argue for this distinction by introducing a general model which allows us to identify, describe, and compare a ...
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Content providers often face legal or economic pressures to censor or remove objectionable or infringing content they host. While decentralized providers can enable censorship-resistant storage, centralized content providers remain popular for performance and usability reasons. But centralized content providers can always choose not to respond to requests for a specific file, making it difficul...
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All three-manifolds are known to occur as Cauchy surfaces of asymptotically flat vacuum spacetimes and of spacetimes with positive-energy sources. We prove here the conjecture that general relativity does not allow an observer to probe the topology of spacetime: any topological structure collapses too quickly to allow light to traverse it. More precisely, in a globally hyperbolic, asymptoticall...
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A new class of X-ray sources was clearly established with the discovery of highly relativistic radio jets from the galactic sources GRS 1915+105 and GRO J1655-40. Both of these objects have given us a broader view of black holes and the formation of jets, yet they also show the complexity of the accretion environment near relativistic objects. The fast apparent motion of the jets, their luminos...
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ژورنال
عنوان ژورنال: Nuclear Physics B - Proceedings Supplements
سال: 2000
ISSN: 0920-5632
DOI: 10.1016/s0920-5632(00)00782-9