Understanding digital intelligence and the norms that might govern it

Abstract: This paper describes the nature of digital intelligence and provides context for the material published as a result of the actions of National Security Agency contractor Edward Snowden. It looks at the dynamic interaction between demands from government and law enforcement for digital intelligence, and at the new possibilities that digital technology has opened up for meeting such demands. The adequacy of previous regimes of legal powers and governance arrangements is seriously challenged just at a time when the objective need for intelligence on the serious threats facing civil society is apparent. This paper suggests areas where it might be possible to derive international norms, regarded as promoting standards of accepted behaviour that might gain widespread, if not universal, international acceptance, for the safe practice of digital intelligence

The connection between galaxy structure and quenching efficiency

Using data from the SDSS-DR7, including structural measurements from 2D surface brightness fits with GIM2D, we show how the fraction of quiescent galaxies depends on galaxy stellar mass $M_*$, effective radius $R_e$, fraction of $r-$band light in the bulge, $B/T$, and their status as a central or satellite galaxy at $0.01<z<0.2$. For central galaxies we confirm that the quiescent fraction depends not only on stellar mass, but also on $R_e$. The dependence is particularly strong as a function of $M_*/R_e^\alpha$, with $\alpha\sim 1.5$. This appears to be driven by a simple dependence on $B/T$ over the mass range $9 < \log(M_*/M_\odot) < 11.5$, and is qualitatively similar even if galaxies with $B/T>0.3$ are excluded. For satellite galaxies, the quiescent fraction is always larger than that of central galaxies, for any combination of $M_*$, $R_e$ and $B/T$. The quenching efficiency is not constant, but reaches a maximum of $\sim 0.7$ for galaxies with $9 < \log(M_*/M_\odot) < 9.5$ and $R_e<1$ kpc. This is the same region of parameter space in which the satellite fraction itself reaches its maximum value, suggesting that the transformation from an active central galaxy to a quiescent satellite is associated with a reduction in $R_e$ due to an increase in dominance of a bulge component.Comment: 17 pages, 28 figures, accepted to MNRAS. Catalog available at http://quixote.uwaterloo.ca/~mbalogh/downloads/Omand_published.fit

The body as image: image as body

Pain consultations are often contested spaces where patient and clinician compete for the roles of speaker. Often patients are searching for mechanical explanations and clinicians for psychological ones - creating an impasse and causing distress to both parties. Meanwhile, as technology advances and we have increasing means of seeing inside a person’s body we seem to have less and less ability to see inside another’s world – to understand what it means to live with pain, the significance of that pain for that individual in their social context. In this paper we explore the potential for images of pain, co-created with patients, to intervene in this unproductive patient dynamic and bring the full experience of pain - social, emotional, physical - into focus. Narrative analysis is used on a series of transcripts of pain consultations

Multistability in an unusual phase diagram induced by the competition between antiferromagnetic-like short-range and ferromagnetic-like long-range interactions

The interplay between competing short-range (SR) and long-range (LR) interactions can cause nontrivial structures in phase diagrams. Recently, horn-shaped unusual structures were found by Monte Carlo simulations in the phase diagram of the Ising antiferromagnet (IA) with infinite-range ferromagnetic-like (F) interactions [Phys. Rev. B {\bf 93}, 064109 (2016); {\bf 96}, 174428 (2017)], and also in an IA with LR interactions of elastic origin modeling spin-crossover materials [Phys. Rev. B {\bf 96}, 144425 (2017)]. To clarify the nature of the phases associated with the horn structures, we study the phase diagram of the IA model with infinite-range F interactions by applying a variational free energy in a cluster mean-field (CMF) approximation. While the simple Bragg-Williams mean-field theory for each sublattice does not produce a horn structure, we find such structures with the CMF method. This confirms that the local thermal fluctuations enabled by the multisite clusters are essential for this phenomenon. We investigate in detail the structure of metastable phases in the phase diagram. In contrast to the phase diagram obtained by the Monte Carlo studies, we find a triple point, at which ferromagnetic-like, antiferromagnetic-like, and disordered phases coexist, and also six tristable regions accompanying the horn structure. We also point out that several characteristic endpoints of first-order transitions appear in the phase diagram. We propose three possible scenarios for the transitions related to the tristable regions. Finally, we discuss the relation between the triple point in this phase diagram and that of a possible lattice-gas model, in which solid, liquid, and gas phases can coexist.Comment: 28 pages, 11 figure

Sinking flux of particulate organic matter in the oceans: Sensitivity to particle characteristics

© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Omand, M. M., Govindarajan, R., He, J., & Mahadevan, A. Sinking flux of particulate organic matter in the oceans: Sensitivity to particle characteristics. Scientific Reports, 10(1), (2020): 5582, doi:10.1038/s41598-020-60424-5.The sinking of organic particles produced in the upper sunlit layers of the ocean forms an important limb of the oceanic biological pump, which impacts the sequestration of carbon and resupply of nutrients in the mesopelagic ocean. Particles raining out from the upper ocean undergo remineralization by bacteria colonized on their surface and interior, leading to an attenuation in the sinking flux of organic matter with depth. Here, we formulate a mechanistic model for the depth-dependent, sinking, particulate mass flux constituted by a range of sinking, remineralizing particles. Like previous studies, we find that the model does not achieve the characteristic ‘Martin curve’ flux profile with a single type of particle, but instead requires a distribution of particle sizes and/or properties. We consider various functional forms of remineralization appropriate for solid/compact particles, and aggregates with an anoxic or oxic interior. We explore the sensitivity of the shape of the flux vs. depth profile to the choice of remineralization function, relative particle density, particle size distribution, and water column density stratification, and find that neither a power-law nor exponential function provides a definitively superior fit to the modeled profiles. The profiles are also sensitive to the time history of the particle source. Varying surface particle size distribution (via the slope of the particle number spectrum) over 3 days to represent a transient phytoplankton bloom results in transient subsurface maxima or pulses in the sinking mass flux. This work contributes to a growing body of mechanistic export flux models that offer scope to incorporate underlying dynamical and biological processes into global carbon cycle models.We thank NSF (OCE 1260080), NASA (NNX16AR48G), and the Ministry of Earth Sciences, Government of India (Monsoon Mission Project on the Bay of Bengal) for support. This work was largely done in 2012 while MMO was a postdoctoral associate at WHOI, during a visit by RG supported by The Mary Sears visiting scholar program to the Woods Hole Oceanographic Institution. Thanks also to Benjamin Hodges for many thoughtful contributions