Thermal effects on the resonance fluorescence of doubly dressed artificial atoms

In this work, robustness of controlled density of optical states in doubly driven artificial atoms is studied under phonon dissipation. By using both perturbative and polaron approaches, we investigate the influence of carrier-phonon interactions on the emission properties of a two-level solid-state emitter, simultaneously coupled to two intense distinguishable lasers. Phonon decoherence effects on the emission spectra are found modest up to neon boiling temperatures ($\sim 30$ K), as compared with photon generation at the Fourier transform limit obtained in absence of lattice vibrations (zero temperature). These results show that optical switching and photonic modulation by means of double dressing, do not require ultra low temperatures for implementation, thus boosting its potential technological applications.Comment: Submitted versio

Material Adverse Change Clauses and Acquisition Dynamics

Material-Adverse-Change clauses (MACs) are present in over 90% of acquisition agreements. These clauses are the outcome of extensive negotiation and exhibit substantial cross-sectional variation in the number and types of events that are excluded from being ‘material adverse events’ (MAEs). MAEs are the underlying cause of more than 50% of acquisition terminations and 60% of acquisition renegotiations. Moreover, these renegotiations lead to substantial changes in the price offered to target shareholders (13-15%). We find that acquisitions with fewer MAE exclusions are characterized by wider arbitrage spreads (i.e., the difference between the price offered to target shareholders and the current market price of the target’s shares) during the acquisition period and are associated with higher offer premiums. We conclude that material adverse change clauses have an economically important impact on the dynamics of corporate acquisitions and stock prices during the acquisition period.Acquisitions, Contractual mechanisms, Material-Adverse-Change clause (MACs), Material-Adverse Event (MAE) exclusions, merger agreement, risk allocation, flexibility

A new strategy for probing the Majorana neutrino CP violating phases and masses

We propose a new strategy for detecting the CP-violating phases and the effective mass of muon Majorana neutrinos by measuring observables associated with neutrino-antineutrino oscillations in $\pi^{\pm}$ decays. Within the generic framework of quantum field theory, we compute the non-factorizable probability for producing a pair of same-charged muons in $\pi^{\pm}$ decays as a distinctive signature of $\nu_{\mu}-\bar{\nu_{\mu}}$ oscillations. We show that an intense neutrino beam through a long baseline experiment is favored for probing the Majorana phases. Using the neutrino-antineutrino oscillation probability reported by MINOS collaboration, a new stringent bound on the effective muon-neutrino mass is derived.Comment: 4 pages, 1 figur

Patrimonio cultural y lingüístico : el montubio y el amorfino.

International audienceLa cultura es uno de los elementos propios a la construcción identitaria. En el caso del Ecuador, las identidades culturales no-hispanas han sido relegadas a un segundo plano durante siglos, debido a la tendencia homogeneizante de la colonia y de los gobiernos republicanos. Sin embargo, la Constitución del 2008 reconoce al Ecuador como un estado plurinacional. Es así como el pueblo montubio se encuentra reconocido dentro de dicha constitución como parte integrante del Estado ecuatoriano y cuyas manifestaciones culturales representan un patrimonio que debe ser preservado. Una de las manifestaciones culturales de este pueblo es el amorfino. Por ende con el fin de preservarlo es necesario definirlo y establecer su vínculo con el pueblo montubio. Si bien el amorfino podría ser calificado como una paremia que tiene su origen en la oralidad, éste concierne igualmente la música y la literatura. No obstante habría que profundizar su estudio con el fin de definirlo y explicar por qué se ha vuelto uno de los “símbolos” del pueblo montubio

Strong Evidence that the Galactic Bulge is Shining in Gamma Rays

There is growing evidence that the Galactic Center Excess identified in the $\textit{Fermi}$-LAT gamma-ray data arises from a population of faint astrophysical sources. We provide compelling supporting evidence by showing that the morphology of the excess traces the stellar over-density of the Galactic bulge. By adopting a template of the bulge stars obtained from a triaxial 3D fit to the diffuse near-infrared emission, we show that it is detected at high significance. The significance deteriorates when either the position or the orientation of the template is artificially shifted, supporting the correlation of the gamma-ray data with the Galactic bulge. In deriving these results, we have used more sophisticated templates at low-latitudes for the $\textit{Fermi}$ bubbles compared to previous work and the three-dimensional Inverse Compton (IC) maps recently released by the ${\tt GALPROP}$ team. Our results provide strong constraints on Millisecond Pulsar (MSP) formation scenarios proposed to explain the excess. We find that an $\textit{admixture formation}$ scenario, in which some of the relevant binaries are $\textit{primordial}$ and the rest are formed $\textit{dynamically}$, is preferred over a primordial-only formation scenario at $7.6\sigma$ confidence level. Our detailed morphological analysis also disfavors models of the disrupted globular clusters scenario that predict a spherically symmetric distribution of MSPs in the Galactic bulge. For the first time, we report evidence of a high energy tail in the nuclear bulge spectrum that could be the result of IC emission from electrons and positrons injected by a population of MSPs and star formation activity from the same site.Comment: 21 pages, 13 figures, V2: Minor changes to match submitted version, V3: matches JCAP published versio

On the Galois structure of Selmer groups

Let A be an abelian variety defined over a number field k and F a finite Galois extension of k. Let p be a prime number. Then under certain not-too-stringent conditions on A and F, we investigate the explicit Galois structure of the p-primary Selmer group of A over F. We also use the results so obtained to derive new bounds on the growth of the Selmer rank of A over extensions of k

On Mordell–Weil groups and congruences between derivatives of twisted Hasse–Weil L-functions

Let A be an abelian variety defined over a number field k and let F be a finite Galois extension of k. Let p be a prime number. Then under certain not-too-stringent conditions on A and F we compute explicitly the algebraic part of the p-component of the equivariant Tamagawa number of the pair (h1(A/F)(1),Z[Gal(F/k)]). By comparing the result of this computation with the theorem of Gross and Zagier we are able to give the first verification of the p-component of the equivariant Tamagawa number conjecture for an abelian variety in the technically most demanding case in which the relevant Mordell–Weil group has strictly positive rank and the relevant field extension is both non-abelian and of degree divisible by p. More generally, our approach leads us to the formulation of certain precise families of conjectural p-adic congruences between the values at s = 1 of derivatives of the Hasse–Weil L-functions associated to twists of A, normalised by a product of explicit equivariant regulators and periods, and to explicit predictions concerning the Galois structure of Tate–Shafarevich groups. In several interesting cases we provide theoretical and numerical evidence in support of these more general predictions

Military Involvement in COVID-19 Responses: Comparing Asia and Latin America

Across the world, governments mobilised the military to support COVID-19 relief efforts. Especially in Asia and Latin America, where the military was extensively involved, this raised concerns about the negative implications for democratic quality and human rights. However, only in a few of the two regions' countries did the military hijack or supplant civilian politics during the pandemic. In both regions, militaries performed numerous tasks during the pandemic, staffing the health bureaucracy, producing medical equipment, providing healthcare services, delivering logistics, and enforcing public-security measures. The extensive reliance on the military's organisational resources, however, did not necessarily lead to the political ascendance of the armed forces or the erosion of democratic quality. Military participation in COVID-19 relief efforts undermined democracy and human rights only where the armed forces had been a pivotal actor in the context of institutionally weak democracies or militarised dictatorships already prior to 2020