Eminent Pearsonians: Britishness, Anti-Britishness, and Canadianism

Britishness in mid-Twentieth century Canada is usually treated as a fading overseas tie, a foreign allegiance, or a mark of dependency and colonial immaturity. There is a tendency to assume a kind of Manichean division between pro-British and anti-British: either in favour of Canadian independence, or beholden to the British connection, and to draw too sharp a distinction between what was “British” and what was genuinely “Canadian.” However, a study of the Eminent Pearsonians – three generations of Canadians whose anglophilia and Canadianness were intermingled – suggests that they were neither purely anglophile nor quite anglophobe but a tertium quid. Britishness and Canadianism were far more interpenetrated than is commonly thought. The nationalism and internationalism of Pearson and his contemporaries adumbrated their adoptive English liberalism and British liberal imperialism. Indeed, Britishness was interwoven into the Canadianness of the actors, bit-players, and stage-hands of all classes, ethnicities and genders in the Canadian pageant. In the positive sense of the term, Canadianism was an excrescence of Britishness.On a habituellement interprété la « britannicité » du Canada au milieu du XXe siècle comme un lien outre-atlantique évanescent, un sentiment d’allégeance à un pays étranger, ou un signe de dépendance et d’immaturité coloniale. On a tendance à diviser de façon manichéenne les pro- et les antibritanniques – les uns favorables au lien britannique, les autres, à l’indépendance du Canada – et de distinguer sans nuance ce qui est « britannique » de ce qui est authentiquement « canadien ». Toutefois, une étude portant sur les célèbres Pearsoniens (trois générations de Canadiens qui ont assumé à la fois leur anglophilie et leur « canadianité ») suggère qu’ils n’étaient ni purement anglophiles ni tout à fait anglophobes, mais qu’ils se situaient entre les deux. La britannicité et la canadianité s’interpénétraient bien plus qu’on le pense généralement. Le nationalisme et l’internationalisme pratiqués par Pearson et ses contemporains étaient teintés de libéralisme anglais et d’impérialisme libéral britannique. En fait, la britannicité a coloré la canadianité de tous ceux et celles qui, de près ou de loin, et quelles qu’aient été leurs origines sociales et ethniques, ont participé à l’aventure historique canadienne. Dans le sens positif du terme, le canadianisme était une excroissance de la britannicité

A ratio model of perceived speed in the human visual system

The perceived speed of moving images changes over time. Prolonged viewing of a pattern (adaptation) leads to an exponential decrease in its perceived speed. Similarly, responses of neurones tuned to motion reduce exponentially over time. It is tempting to link these phenomena. However, under certain conditions, perceived speed increases after adaptation and the time course of these perceptual effects varies widely. We propose a model that comprises two temporally tuned mechanisms whose sensitivities reduce exponentially over time. Perceived speed is taken as the ratio of these filters' outputs. The model captures increases and decreases in perceived speed following adaptation and describes our data well with just four free parameters. Whilst the model captures perceptual time courses that vary widely, parameter estimates for the time constants of the underlying filters are in good agreement with estimates of the time course of adaptation of direction selective neurones in the mammalian visual system

Can we see pulsars around Sgr A*? - The latest searches with the Effelsberg telescope

Radio pulsars in relativistic binary systems are unique tools to study the curved space-time around massive compact objects. The discovery of a pulsar closely orbiting the super-massive black hole at the centre of our Galaxy, Sgr A*, would provide a superb test-bed for gravitational physics. To date, the absence of any radio pulsar discoveries within a few arc minutes of Sgr A* has been explained by one principal factor: extreme scattering of radio waves caused by inhomogeneities in the ionized component of the interstellar medium in the central 100 pc around Sgr A*. Scattering, which causes temporal broadening of pulses, can only be mitigated by observing at higher frequencies. Here we describe recent searches of the Galactic centre region performed at a frequency of 18.95 GHz with the Effelsberg radio telescope.Comment: 3 pages, 2 figures, Proceedings of IAUS 291 "Neutron Stars and Pulsars: Challenges and Opportunities after 80 years", 201

Limits on the Mass, Velocity and Orbit of PSR J1933−-6211

We present a high-precision timing analysis of PSR J1933$-$6211, a millisecond pulsar (MSP) with a 3.5-ms spin period and a white dwarf (WD) companion, using data from the Parkes radio telescope. Since we have accurately measured the polarization properties of this pulsar we have applied the matrix template matching approach in which the times of arrival are measured using full polarimetric information. We achieved a weighted root-mean-square timing residuals (rms) of the timing residuals of 1.23 $\rm \mu s$, 15.5$\%$ improvement compared to the total intensity timing analysis. After studying the scintillation properties of this pulsar we put constraints on the inclination angle of the system. Based on these measurements and on $\chi^2$ mapping we put a 2-$\sigma$ upper limit on the companion mass (0.44 M$_\odot$). Since this mass limit cannot reveal the nature of the companion we further investigate the possibility of the companion to be a He WD. Applying the orbital period-mass relation for such WDs, we conclude that the mass of a He WD companion would be about 0.26$\pm$0.01 M$_\odot$ which, combined with the measured mass function and orbital inclination limits, would lead to a light pulsar mass $\leqslant$ 1.0 M$_\odot$. This result seems unlikely based on current neutron star formation models and we therefore conclude that PSR J1933$-$6211 most likely has a CO WD companion, which allows for a solution with a more massive pulsar