The set of all orthogonal complex structures on the flat 66-tori

In \cite{BSV}, Borisov, Salamon and Viaclovsky constructed non-standard orthogonal complex structures on flat tori $T^{2n}_{\mathbb R}$ for any $n\geq 3$. We will call these examples BSV-tori. In this note, we show that on a flat $6$-torus, all the orthogonal complex structures are either the complex tori or the BSV-tori. This solves the classification problem for compact Hermitian manifolds with flat Riemannian connection in the case of complex dimension three.Comment: 14 page

An Estimated DSGE Model of the Indian Economy

We develop a closed-economy DSGE model of the Indian economy and estimate it by Bayesian Maximum Likelihood methods using Dynare. We build up in stages to a model with a number of features important for emerging economies in general and the Indian economy in particular: a large proportion of credit-constrained consumers, a financial accelerator facing domestic firms seeking to finance their investment, and an informal sector. The simulation properties of the estimated model are examined under a generalized inflation targeting Taylor-type interest rate rule with forward and backward-looking components. We find that, in terms of model posterior probabilities and standard moments criteria, inclusion of the above financial frictions and an informal sector significantly improves the model fit.Indian economy, DSGE model, Bayesian estimation, monetary interest rate rules, financial frictions

An Estimated DSGE Model of the Indian Economy.

We develop a closed-economy DSGE model of the Indian economy and estimate it by Bayesian Maximum Likelihood methods using Dynare. We build up in stages to a model with a number of features important for emerging economies in general and the Indian economy in particular: a large proportion of credit-constrained consumers, a financial accelerator facing domestic firms seeking to finance their investment, and an informal sector. The simulation properties of the estimated model are examined under a generalized inflation targeting Taylor-type interest rate rule with forward and backward-looking components. We find that, in terms of model posterior probabilities and standard moments criteria, inclusion of the above financial frictions and an infor- mal sector significantly improves the model fit.Indian economy ; DSGE model ; Bayesian estimation ; Monetary interest rate rules ; Financial frictions

On the (ir)relevance of direct supply-side effects of monetary policy

The relevance of direct supply-side effects of monetary policy in a New Keynesian DSGE model is studied. We extend a model with several nominal and real frictions by introducing a cost channel of monetary transmission and allowing for non-separability of money and consumption in the utility of the representative household. These fea- tures have important theoretical consequences for the output-inflation trade-off and indeterminacy of interest rate rules. The empirical evidence for these effects are then examined using a Bayesian maximum likelihood framework complemented with GMM single-equation estimation. Both estimation strategies point to weak evidence for the cost channel and non-separable utility.New Keynesian model, Bayesian maximum likelihood estimation, GMM, non-separable utility, cost channel.

An Estimated DSGE Model of the Indian Economy

We develop a closed-economy DSGE model of the Indian economy and estimate it by Bayesian Maximum Likelihood methods using Dynare. We build up in stages to a model with a number of features important for emerging economies in general and the Indian economy in particular: a large proportion of credit-constrained consumers, a financial accelerator facing domestic firms seeking to finance their investment, and an informal sector. The simulation properties of the estimated model are examined under a generalized inflation targeting Taylor-type interest rate rule with forward and backward-looking components. We find that, in terms of model posterior probabilities and standard moments criteria, inclusion of the above financial frictions and an informal sector significantly improves the model fit.Indian economy, DSGE model, Bayesian estimation, monetary interest rate rules, financial frictions.

Highly Dispersive Electron Relaxation and Colossal Thermoelectricity in the Correlated Semiconductor FeSb2_2

We show that the colossal thermoelectric power, $S(T)$, observed in the correlated semiconductor FeSb$_2$ below 30\,K is accompanied by a huge Nernst coefficient $\nu(T)$ and magnetoresistance MR$(T)$. Markedly, the latter two quantities are enhanced in a strikingly similar manner. While in the same temperature range, $S(T)$ of the reference compound FeAs$_2$, which has a seven-times larger energy gap, amounts to nearly half of that of FeSb$_2$, its $\nu(T)$ and MR$(T)$ are intrinsically different to FeSb$_2$: they are smaller by two orders of magnitude and have no common features. With the charge transport of FeAs$_2$ successfully captured by the density functional theory, we emphasize a significantly dispersive electron-relaxation time $\tau(\epsilon_k)$ due to electron-electron correlations to be at the heart of the peculiar thermoelectricity and magnetoresistance of FeSb$_2$.Comment: 8 pages, 5 figure

COUPLAGE NON LINÉAIRE PHASE-AMPLITUDE DANS LES RÉSONATEURS

National audienc

Molecular outflow launched beyond the disk edge

One of the long-standing problems of star formation is the excess of angular momentum of the parent molecular cloud. In the classical picture, a fraction of angular momentum of the circumstellar material is removed by the magneto-centrifugally driven disk wind that is launched from a wide region throughout the disk. In this work, we investigate the kinematics in the envelope-disk transition zone of the Class I object BHB07-11, in the B59 core. For this purpose, we used the Atacama Large Millimeter/submillimeter Array in extended configuration to observe the thermal dust continuum emission ($\lambda_0 \sim$ 1.3 mm) and molecular lines (CO, C$^{18}$O and H$_2$CO), which are suitable tracers of disk, envelope, and outflow dynamics at a spatial resolution of $\sim 30$ AU. We report a bipolar outflow that was launched at symmetric positions with respect to the disk ($\sim$80~AU in radius), but was concentrated at a distance of 90--130~AU from the disk center. The two outflow lobes had a conical shape and the gas inside was accelerating. The large offset of the launching position coincided with the landing site of the infall material from the extended spiral structure (seen in dust) onto the disk. This indicates that bipolar outflows are efficiently launched within a narrow region outside the disk edge. We also identify a sharp transition in the gas kinematics across the tip of the spiral structure, which pinpoints the location of the so-called centrifugal barrier.Comment: 5 pages, 5 figures, Accepted for publication in A&A Letter

Dynamic Rupture Models, Fault Interaction and Ground Motion Simulations for the Segmented Húsavík‐Flatey Fault Zone, Northern Iceland

The Húsavík-Flatey Fault Zone (HFFZ) is the largest strike-slip fault in Iceland and poses a high seismic risk to coastal communities. To investigate physics-based constraints on earthquake hazards, we construct three fault system models of varying geometric complexity and model 79 3-D multi-fault dynamic rupture scenarios in the HFFZ. By assuming a simple regional prestress and varying hypocenter locations, we analyze the rupture dynamics, fault interactions, and the associated ground motions up to 2.5 Hz. All models account for regional seismotectonics, topo-bathymetry, 3-D subsurface velocity, viscoelastic attenuation, and off-fault plasticity, and we explore the effect of fault roughness. The rupture scenarios obey earthquake scaling relations and predict magnitudes comparable to those of historical events. We show how fault system geometry and segmentation, hypocenter location, and prestress can affect the potential for rupture cascading, leading to varying slip distributions across different portions of the fault system. Our earthquake scenarios yield spatially heterogeneous near-field ground motions modulated by geometric complexities, topography, and rupture directivity, particularly in the near-field. The average ground motion attenuation characteristics of dynamic rupture scenarios of comparable magnitudes and mean stress drop are independent of variations in source complexity, magnitude-consistent and in good agreement with the latest regional empirical ground motion models. However, physics-based ground motion variability changes considerably with fault-distance and increases for unilateral compared to bilateral ruptures. Systematic variations in physics-based near-fault ground motions provide important insights into the mechanics and potential earthquake hazard of large strike-slip fault systems, such as the HFFZ