Better than words: expressing feelings with foods in Mass Observation wartime diaries

This paper, based on the examination of selected wartime diaries from the Mass Observation Archive, tackles the expression of intimate feelings through food practices. Exploring personal testimonies, it presents how, during a time of scarcity and shortage, food becomes a precious accessory to express personal feelings and a supportive medium to demonstrate love or friendship to friends or loved ones, whomever and wherever they could be. The result of this exploration, supported by various studies and reports on wartime emotions and human behaviours, shows how personal feelings were expressed by something better than words: valuable food. It also demonstrates to what extent the smallest emotional boundary can become vital when facing hard times through some examples of quite peculiar behaviours reported by the diarists. From the gift of a piece of cheese to the sacrifice of the meat ration, this paper suggests that food practices can become a valuable indicator of personal feelings such as love and friendship, but also loneliness and anxiety

Compiling and securing cryptographic protocols

Protocol narrations are widely used in security as semi-formal notations to specify conversations between roles. We define a translation from a protocol narration to the sequences of operations to be performed by each role. Unlike previous works, we reduce this compilation process to well-known decision problems in formal protocol analysis. This allows one to define a natural notion of prudent translation and to reuse many known results from the literature in order to cover more crypto-primitives. In particular this work is the first one to show how to compile protocols parameterised by the properties of the available operations.Comment: A short version was submitted to IP

Finitary Deduction Systems

Cryptographic protocols are the cornerstone of security in distributed systems. The formal analysis of their properties is accordingly one of the focus points of the security community, and is usually split among two groups. In the first group, one focuses on trace-based security properties such as confidentiality and authentication, and provides decision procedures for the existence of attacks for an on-line attackers. In the second group, one focuses on equivalence properties such as privacy and guessing attacks, and provides decision procedures for the existence of attacks for an offline attacker. In all cases the attacker is modeled by a deduction system in which his possible actions are expressed. We present in this paper a notion of finitary deduction systems that aims at relating both approaches. We prove that for such deduction systems, deciding equivalence properties for on-line attackers can be reduced to deciding reachability properties in the same setting.Comment: 30 pages. Work begun while in the CASSIS Project, INRIA Nancy Grand Es

Supernova Shock Breakout Through a Wind

The breakout of a supernova shock wave through the progenitor star's outer envelope is expected to appear as an X-ray flash. However, if the supernova explodes inside an optically-thick wind, the breakout flash is delayed. We present a simple model for estimating the conditions at shock breakout in a wind based on the general observable quantities in the X-ray flash lightcurve: the total energy E_X, and the diffusion time after the peak, t_diff. We base the derivation on the self-similar solution for the forward-reverse shock structure expected for an ejecta plowing through a pre-existing wind at large distances from the progenitor's surface. We find simple quantitative relations for the shock radius and velocity at breakout. By relating the ejecta density profile to the pre-explosion structure of the progenitor, the model can also be extended to constrain the combination of explosion energy and ejecta mass. For the observed case of XRO08109/SN2008D, our model provides reasonable constraints on the breakout radius, explosion energy, and ejecta mass, and predicts a high shock velocity which naturally accounts for the observed non-thermal spectrum.Comment: Accepted for publication in MNRAS (v3: minor changes in the discussion of XRO08109/SN2008D, conclusions unchanged