A proof of strong cosmic censorship is presented for a class of solutions of the Einstein-Maxwell equations, those with polarized Gowdy symmetry. A key element of the argument is the observation that by means of a suitable choice of variables the central equations in this problem can be written in a form where they are identical to the central equations for general (i.e. non-polarized) vacuum G...

Analysing censorship incidents targeting popular circumvention tools such as Tor can be a tedious task. Access to censoring networks is typically difficult to obtain and remote analysis is not always possible. Analysis is however feasible if users behind the censoring networks are given the opportunity to help. In this paper, we propose a lightweight censorship analyser for Tor which is meant t...

Internet censorship is on the rise as websites around the world are increasingly blocked by government-level firewalls. Although popular anonymizing networks like Tor were originally designed to keep attackers from tracing people’s activities, many people are also using them to evade local censorship. But if the censor simply denies access to the Tor network itself, blocked users can no longer ...

We design DNS-sly, a counter-censorship system which enables a covert channel between a DNS client and server. To achieve covertness and deniability in the upstream direction, DNS-sly applies user personalization, adapting to individual behaviors. In the downstream direction, it utilizes CDN-related DNS responses to embed data, while retaining statistical covertness. We show DNS-sly achieves do...

A brief review is given of three recent results concerning classical solutions of gravitational theories: (1) With asymptotically anti de Sitter boundary conditions, there are matter theories satisfying the positive energy theorem which violate cosmic censorship. (2) Despite supersymmetry, there are solutions to N = 8 supergravity in which the total gravitational energy is arbitrarily negative....

Despite the high perceived value and increasing severity of online information controls, a data-driven understanding of the phenomenon has remained elusive. In this paper, we consider two design points in the space of Internet censorship measurement with particular emphasis on how they address the challenges of locating vantage points, choosing content to test, and analyzing results. We discuss...

Using an organizational informatics approach, this study explores the implications of human rights organizations’ use of censorship circumvention technologies. Through qualitative analyses of data collected through in-depth interviews, the research examines the factors influencing the use of circumvention technologies and the organizational effects of their use. The outcomes include a revised m...

A proof of strong cosmic censorship is presented for a class of solutions of the Einstein-Maxwell equations, those with polarized Gowdy symmetry. A key element of the argument is the observation that by means of a suitable choice of variables the central equations in this problem can be written in a form where they are identical to the central equations for general (i.e. non-polarized) vacuum G...

Microblogging services such as Twitter are an increasingly important way to communicate, both for individuals and for groups through the use of hashtags that denote topics of conversation. However, groups can be easily blocked from communicating through blocking of posts with the given hashtags. We propose #h00t, a system for censorship resistant microblogging. #h00t presents an interface that ...