Borrowing from thy neighbour : a European perspective on sovereign debt

European capital markets show increasing concern about the extent of sovereign debts and their sustainability. Here we explore some insights that the Overlapping Generations (OLG) framework has to er on such issues. The OLG framework implies, for example, that there is a limit to the amount of debt that may be sustained in a closed economy | with high debt raising interest rates and crowding out capital formation. But capital market integration with less indebted partners allows for a fall in interest rates as a result of borrowing from one's neighbour. Indeed we nd that | in equilibrium | most of the debt of a high indebted country will be transferred to partner countries. Rather like ECB discount policy, our formal analysis is conducted without taking sovereign default risk properly into account, however. We go on to discuss three possible sources of default risk | creditor panic, exogenous interest rate shocks and \over-borrowing" | and we emphasize the need for comparative statics to be complemented by disequilibrium dynamics

Borrowing from thy neighbour: a European perspective on sovereign debt

European capital markets show increasing concern about the extent of sovereign debts and their sustainability. Here we explore some insights that the Overlapping Generations (OLG) framework has to offer on such issues. The OLG framework implies, for example, that there is a limit to the amount of debt that may be sustained in a closed economy- with high debt raising interest rates and crowding out capital formation. But capital market integration with less indebted partners allows for a fall in interest rates as a result of borrowing from one's neighbour. Indeed we find that - in equilibrium - most of the debt of a high indebted country will be transferred to partner countries.debt sustainability, overlapping generations, sovereign default, Euro-zone debt crisis

The electron-phonon processes of the nitrogen-vacancy center in diamond

Applications of negatively charged nitrogen-vacancy center in diamond exploit the center's unique optical and spin properties, which at ambient temperature, are predominately governed by electron-phonon interactions. Here, we investigate these interactions at ambient and elevated temperatures by observing the motional narrowing of the center's excited state spin resonances. We determine that the center's Jahn-Teller dynamics are much slower than currently believed and identify the vital role of symmetric phonon modes. Our results have pronounced implications for center's diverse applications (including quantum technology) and for understanding its fundamental properties.Comment: 5 pages, 4 figure

Interpreting Intuitions

We argue that many intuitions do not have conscious propositional contents. In particular, many of the intuitions had in response to philosophical thought experiments, like Gettier cases, do not have such contents. They are more like hunches, urgings, murky feelings, and twinges. Our view thus goes against the received view of intuitions in philosophy, which we call Mainstream Propositionalism. Our positive view is that many thought-experimental intuitions are conscious, spontaneous, non-theoretical, non-propositional psychological states that often motivate belief revision, but they require interpretation, in light of background beliefs, before a subject can form a propositional judgment as a consequence of them. We call our view Interpretationalism. We argue (i) that Interpretationalism avoids the problems that beset Mainstream Propositionalism and (ii) that our view meshes well with empirical results in contemporary cognitive science

Following one's heart: cardiac rhythms gate central initiation of sympathetic reflexes

Central nervous processing of environmental stimuli requires integration of sensory information with ongoing autonomic control of cardiovascular function. Rhythmic feedback of cardiac and baroreceptor activity contributes dynamically to homeostatic autonomic control. We examined how the processing of brief somatosensory stimuli is altered across the cardiac cycle to evoke differential changes in bodily state. Using functional magnetic resonance imaging of brain and noninvasive beat-to-beat cardiovascular monitoring, we show that stimuli presented before and during early cardiac systole elicited differential changes in neural activity within amygdala, anterior insula and pons, and engendered different effects on blood pressure. Stimulation delivered during early systole inhibited blood pressure increases. Individual differences in heart rate variability predicted magnitude of differential cardiac timing responses within periaqueductal gray, amygdala and insula. Our findings highlight integration of somatosensory and phasic baroreceptor information at cortical, limbic and brainstem levels, with relevance to mechanisms underlying pain control, hypertension and anxiety

Singlet levels of the NV−^{-} centre in diamond

The characteristic transition of the NV- centre at 637 nm is between ${}^3\mathrm{A}_2$ and ${}^3\mathrm{E}$ triplet states. There are also intermediate ${}^1\mathrm{A}_1$ and ${}^1\mathrm{E}$ singlet states, and the infrared transition at 1042 nm between these singlets is studied here using uniaxial stress. The stress shift and splitting parameters are determined, and the physical interaction giving rise to the parameters is considered within the accepted electronic model of the centre. It is established that this interaction for the infrared transition is due to a modification of electron-electron Coulomb repulsion interaction. This is in contrast to the visible 637 nm transition where shifts and splittings arise from modification to the one-electron Coulomb interaction. It is also established that a dynamic Jahn-Teller interaction is associated with the singlet ${}^1\mathrm{E}$ state, which gives rise to a vibronic level 115 $\mathrm{cm}^{-1}$ above the ${}^1\mathrm{E}$ electronic state. Arguments associated with this level are used to provide experimental confirmation that the ${}^1\mathrm{A}_1$ is the upper singlet level and ${}^1\mathrm{E}$ is the lower singlet level.Comment: 19 pages, 6 figure