On SU(3)FSU(3)_{F} Breaking through Final State Interactions and CP Asymmetries in D→PPD\to P P Decays

We analyse $D$ decays to two pseudoscalars $(\pi,K)$ assuming the dominant source of $\mathrm{SU}(3)_F$ breaking lies in final state interactions. We obtain an excellent agreement with experimental data and are able to predict CP violation in several channels based on current data on branching ratios and $\Delta \mathrm{A_{CP}}$. We also make predictions for $\delta_{K\pi}$ and the branching fraction for the decay $D_s^+\to K^+K_L$.Comment: 21 pages. Updated with the 2019 measurement of $\Delta \mathrm{A_{CP}}$ from LHC

Long-lived oscillatory incoherent electron dynamics in molecules: trans-polyacetylene oligomers

We identify an intriguing feature of the electron-vibrational dynamics of molecular systems via a computational examination of \emph{trans}-polyacetylene oligomers. Here, via the vibronic interactions, the decay of an electron in the conduction band resonantly excites an electron in the valence band, and vice versa, leading to oscillatory exchange of electronic population between two distinct electronic states that lives for up to tens of picoseconds. The oscillatory structure is reminiscent of beating patterns between quantum states and is strongly suggestive of the presence of long-lived molecular electronic coherence. Significantly, however, a detailed analysis of the electronic coherence properties shows that the oscillatory structure arises from a purely incoherent process. These results were obtained by propagating the coupled dynamics of electronic and vibrational degrees of freedom in a mixed quantum-classical study of the Su-Schrieffer-Heeger Hamiltonian for polyacetylene. The incoherent process is shown to occur between degenerate electronic states with distinct electronic configurations that are indirectly coupled via a third auxiliary state by the vibronic interactions. A discussion of how to construct electronic superposition states in molecules that are truly robust to decoherence is also presented

Dynamic Coordination via Organizational Routines

We investigate dynamic coordination among members of a problem solving team who receive private signals about which of their actions are required for a (static) coordinated solution and who have repeated opportunities to explore different action combinations. In this environment ordinal equilibria, in which agents condition only on how their signals rank their actions and not on signal strength, lead to simple patterns of behavior that have a natural interpretation as routines. These routine spartially solve the team’s coordination problem by synchronizing the team’s search efforts and prove to be resilient to changes in the environment by being expost equilibria, to agents having only a coarse understanding of other agents’ strategies by being fully cursed, and to natural forms of agents’ overcon?dence. The price of this resilience is that optimal routines are frequently not optimal equilibria

Corn Market Dynamics and the Joint Executive Committee (1880 - 1886)

We incorporate previously omitted controls of external conditions in transportation and commodity markets into Porter’s (1983) analysis of industry demand, conduct and stability of the JEC railroad cartel. We estimate the equilibrium price path, non-parametrically, and find that the reaction of the JEC in its rate setting to the nature of rate setting, over alternative modes of conveyance, is very much predicted by the theoretical considerations in Haltiwanger and Harrington (1991). Periods of Cartel instability are triggered by unexpected booms in corn markets in New York, amongst other factors. The latter is consistent with the Green and Porter (1984) theory.Corn Market Spot and Future Weekly Prices in Chicago and New York, Demand Cycles, Inventory Management in New York, JEC Railroad Cartel Pricing, Outside Transportation Options, Structural Modeling.

Embedding Consumer Taste for Location into a Structural Model of Equilibrium

Given that brands (products) are location specific in terms of coverage of retail stores, we allow consumers to have preferences over location and products to carry distribution costs, alongside preferences and costs over other observable and unobservable product characteristics. We embed these considerations into Berry, Levinsohn and Pakes (1995) to jointly estimate demand and cost parameters for brands (products) in Retail Carbonated Soft Drinks. Allowing for location has a very significant impact on estimated primitives and the predictive power of the structural model. As a counterfactual exercise we show the e?ects on welfare of an equilibrium that results from a change in the distribution of consumer taste for location.

Rational Multi-Agent Search

We study games in which players search for an optimal action profile. All action profiles are either a success, with a payoff of one, or a failure, with a payoff of zero. Players do not know the location of success profiles; instead each player is privately informed about the marginal distribution of success profiles over his actions. We characterize optimal joint search strategies.Search, Decentralization, Symmetry

Robust ultrafast currents in molecular wires through Stark shifts

A novel way to induce ultrafast currents in molecular wires using two incident laser frequencies, $\omega$ and $2\omega$, is demonstrated. The mechanism relies on Stark shifts, instead of photon absorption, to transfer population to the excited states and exploits the temporal profile of the field to generate phase controllable transport. Calculations in a \emph{trans}-polyacetylene oligomer coupled to metallic leads indicate that the mechanism is highly efficient and robust to ultrafast electronic dephasing processes induced by vibronic couplings.Comment: 4 pages, 2 figures, accepted to Physical Review Letter

Dynamic Coordination via Organizational Routines

We investigate dynamic coordination among members of a problem solving team who receive private signals about which of their actions are required for a (static) coordinated solution and who have repeated opportunities to explore different action combinations. In this environment ordinal equilibria, in which agents condition only on how their signals rank their actions and not on signal strength, lead to simple patterns of behavior that have a natural interpretation as routines. These routine spartially solve the team’s coordination problem by synchronizing the team’s search efforts and prove to be resilient to changes in the environment by being expost equilibria, to agents having only a coarse understanding of other agents’ strategies by being fully cursed, and to natural forms of agents’ overcon?dence. The price of this resilience is that optimal routines are frequently not optimal equilibria.