The possibility of a connection between dark energy and gravity through a direct coupling in the Lagrangian of the underlying theory has acquired an increasing interest due to the recently discovered capability of the extended quintessence model to encompass the fine-tuning problem of the cosmological constant. The gravity induced “R-boost” mechanism is indeed responsible for an early, enhanced...

A brief review of the modern state of quantum cosmology is presented as a theory of quantum initial conditions for inflationary scenario. The no-boundary and tunneling states of the Universe are discussed as a possible source of probability peaks in the distribution of initial data for inflation. It is emphasized that in the tree-level approximation the existence of such peaks is in irreconcila...

This paper deals with the response of homogeneous and inhomogeneous rings of coupled oscillators where each individual oscillator, when uncoupled from the others, is chaotic. It is shown that coupling can bring about a wide variety of global responses, and that there is a significant range of coupling values when the response of the ring is periodic despite the fact that each oscillator is chao...

Gauge symmetries in teleparallel gravity, together with the identities among dynamical equations they provide, are analyzed relation to way condition coupling between matter and gravity. Particularly, of fermionic seems be excluded a wide range theories.

In this study, a fractal, Y-shaped dual-mode resonator bandpass filter (BPF) with input-output cross-coupling is introduced. A parallel-coupling feed structure with a cross coupling has been used to generate two transmission zeroes (TZs) near the lower and upper cutoff frequency that can effectively improve the passband edge selectivity. Also, a fractal shaped based on conventional diamond and ...

This paper investigates the synchronization of directed networks whose coupling matrices are reducible and asymmetrical by pinning-controlled schemes. A strong sufficient condition is obtained to guarantee that the synchronization of the kind of networks can be achieved. For the weakly connected network, a method is presented in detail to solve two challenging fundamental problems arising in pi...

The effect of molecular vibrations on electronic transport is investigated with the smallest fullerene C20 bridge, utilizing the Keldysh nonequilibrium Green's function techniques combined with the tight-binding molecular-dynamics method. Large discontinuous steps appear in the differential conductance when the applied bias voltage matches particular vibrational energies. The magnitude of the s...