2,860 research outputs found
Higher Order Approximation to the Hill Problem Dynamics about the Libration Points
An analytical solution to the Hill problem Hamiltonian expanded about the
libration points has been obtained by means of perturbation techniques. In
order to compute the higher orders of the perturbation solution that are needed
to capture all the relevant periodic orbits originated from the libration
points within a reasonable accuracy, the normalization is approached in complex
variables. The validity of the solution extends to energy values considerably
far away from that of the libration points and, therefore, can be used in the
computation of Halo orbits as an alternative to the classical
Lindstedt-Poincar\'e approach. Furthermore, the theory correctly predicts the
existence of the two-lane bridge of periodic orbits linking the families of
planar and vertical Lyapunov orbits.Comment: 28 pages, 8 figure
La poética de la analogía y del fragmento en la poesía de Govoni
The analogy’s and objects’s poetics, inheritated from D’Annunzio’s and Pascoli’s symbolism, meet in Govoni’s poetry. This poet manifests his own poetic identity through these both traditions but at the same time he is able “to cross” them in a personal way. At the first stage, the objects’s poetic, as fragment’s poetic, is expressed in the highest degree under the form of the “cataloghe-poem” and the “litany-poem”; then follows a more dynamic and free use of images which in a explicit way presents in the poem the effect of a totality. Finally, in the age of maturity, the pure analogy’s poetic imposes itself: the poem rises from a nucleus of images and its frame corresponds closely to the dynamism of the analogy. We examine in this essay specially the forms of the fragment’s poetic: the list of objects and the juxtaposition of images, and at the end we offer a series of considerations about the analogy’s poetic. Simultaneously we try to draw an itinerary of Govoni’s poetry and a portrait of his identity, how the sensorial function, which defines his personality, relates with other functions of the conscience, like sentiment, thought and intuition
Fine Structure of Open Shell Diatomic Molecules in Combined Electric and Magnetic Fields
We present a theoretical study of the impact of an electric field combined
with a magnetic field on the rotational dynamics of open shell diatomic
molecules. Within the rigid rotor approximation, we solve the time-independent
Schr\"odinger equation including the fine-structure interactions and the
\Lambda-doubling effects. We consider three sets of molecule specific
parameters and several field regimes and investigate the interplay between the
different interactions identifying the dominant one. The possibility of
inducing couplings between the spin and rotational degrees of freedom is
demonstrated.Comment: 11 pages, 16 figure
Steady-state phase diagram of a driven QED-cavity array with cross-Kerr nonlinearities
We study the properties of an array of QED-cavities coupled by nonlinear
elements in the presence of photon leakage and driven by a coherent source. The
main effect of the nonlinear couplings is to provide an effective cross-Kerr
interaction between nearest-neighbor cavities. Additionally, correlated photon
hopping between neighboring cavities arises. We provide a detailed mean-field
analysis of the steady-state phase diagram as a function of the system
parameters, the leakage, and the external driving, and show the emergence of a
number of different quantum phases. A photon crystal associated to a spatial
modulation of the photon blockade appears. The steady state can also display
oscillating behavior and bistability. In some regions the crystalline ordering
may coexist with the oscillating behavior. Furthermore we study the effect of
short-range quantum fluctuations by employing a cluster mean-field analysis.
Focusing on the corrections to the photon crystal boundaries, we show that,
apart for some quantitative differences, the cluster mean field supports the
findings of the simple single-site analysis. In the last part of the paper we
concentrate on the possibility to build up the class of arrays introduced here,
by means of superconducting circuits of existing technology. We consider a
realistic choice of the parameters for this specific implementation and discuss
some properties of the steady-state phase diagram.Comment: 11 pages, 12 figure
Photon solid phases in driven arrays of nonlinearly coupled cavities
We introduce and study the properties of an array of QED cavities coupled by
nonlinear elements, in the presence of photon leakage and driven by a coherent
source. The nonlinear couplings lead to photon hopping and to nearest-neighbor
Kerr terms. By tuning the system parameters, the steady state of the array can
exhibit a photon crystal associated with a periodic modulation of the photon
blockade. In some cases, the crystalline ordering may coexist with phase
synchronization. The class of cavity arrays we consider can be built with
superconducting circuits of existing technology.Comment: 8 pages, 8 figures. Published versio
Los mitos y Jung
En su autobiografía Recuerdos, sueños, pensamientos, Jung, al explicar la dinámica de su obra, señala el momento crucial en el que se le plantea como exigencia ineludible el conocimiento y el estudio de los mitos. Se trata del momento que precede y prepara la escritura de su obra Símbolos de transformación, publicada en 1912. Es el momento en que su relación con Freud entra en crisis, crisis que desemboca en ruptura precisamente con la publicación de ese libro, cuyos contenidos se desmarcan claramente de la doctrina de Freud. En ese tiempo que precede a 1912, la relación de Jung y de Freud es muy intensa. Hacen juntos en 1909 un viaje a EE.UU., que duró siete semanas y Jung narra cómo, estando juntos todos los días, analizaban mutuamente sus sueños
Some definable types that cannot be amalgamated
We exhibit a theory where definable types lack the amalgamation property.Comment: 4 page
The domination monoid in henselian valued fields
We study the domination monoid in various classes of structures arising from
the model theory of henselian valuations, including RV-expansions of henselian
valued fields of residue characteristic 0 (and, more generally, of benign
valued fields), p-adically closed fields, monotone D-henselian differential
valued fields with many constants, regular ordered abelian groups, and pure
short exact sequences of abelian structures. We obtain Ax-Kochen-Ershov type
reductions to suitable fully embedded families of sorts in quite general
settings, and full computations in concrete ones.Comment: 35 pages. Minor revisio
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