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The kinetic equation of nonlocal and non-instantaneous character unifies the
achievements of the transport in dense quantum gases with the Landau theory of
quasiclassical transport in Fermi systems. Large cancellations in the off-shell
motion appear which are hidden usually in non-Markovian behaviors. The
remaining corrections are expressed in terms of shifts in space and time that
characterize the non-locality of the scattering process. In this way quantum

This work deals with models described by a single real scalar field in
two-dimensional spacetime. The aim is to propose potentials that support
massless minima and investigate the presence of kinklike structures that
engender polynomial tails. The results unveil the presence of families of
asymmetric solutions with energy density and linear stability that behave
adequately, enhancing the importance of the analytical study. We stress that
the novel topological structures which we find in this work engender long range

We study the optomechanical behaviour of a driven Fabry-P\'erot cavity
containing two vibrating dielectric membranes. We characterize the cavity-mode
frequency shift as a function of the two-membrane positions, and report a $\sim
2.47$ gain in the optomechanical coupling strength of the membrane relative
motion with respect to the single membrane case. This is achieved when the two
membranes are properly positioned to form an inner cavity which is resonant

We present a novel continuous dynamical decoupling scheme for the
construction of a robust qubit in a three-level system. By means of a clock
transition adjustment, we first show how robustness to environmental noise is
achieved, while eliminating drive-noise, to first-order. We demonstrate this
scheme with the spin sub-levels of the NV-centre's electronic ground state. By
applying drive fields with moderate Rabi frequencies, the drive noise is
eliminated and an improvement of 2 orders of magnitude in the coherence time is

We rigorously investigate the quantum non-Markovian dissipative dynamics of a
system coupled to a harmonic oscillator bath by deriving hierarchical
Schr\"{o}dinger equations of motion (HSEOM) and studying their dynamics. The
HSEOM are the equations for wave functions derived on the basis of the
Feynman-Vernon influence functional formalism for the density operator,
$\langle q|\rho(t)|q' \rangle$, where $\langle q|$ and $|q' \rangle$ are the
left- and right-hand elements. The time evolution of $\langle q|$ is computed

In standard formulations of the uncertainty principle, two fundamental
features are typically cast as impossibility statements: two noncommuting
observables cannot in general both be sharply defined (for the same state), nor
can they be measured jointly. The pioneers of quantum mechanics were acutely
aware and puzzled by this fact, and it motivated Heisenberg to seek a
mitigation, which he formulated in his seminal paper of 1927. He provided
intuitive arguments to show that the values of, say, the position and momentum

The experimental interest and developments in quantum spin-1/2-chains has
increased uninterruptedly over the last decade. In many instances, the target
quantum simulation belongs to the broader class of non-interacting fermionic
models, constituting an important benchmark. In spite of this class being
analytically efficiently tractable, no direct certification tool has yet been
reported for it. In fact, in experiments, certification has almost exclusively

The question of how Bell nonlocality behaves in bipartite systems of higher
dimensions is addressed. By employing the probability of violation of local
realism under random measurements as the figure of merit, we investigate the
nonlocality of entangled qudits with dimensions ranging from $d=2$ to $d=7$. We
proceed in two complementary directions. First, we study the specific Bell
scenario defined by the Collins-Gisin-Linden-Massar-Popescu (CGLMP) inequality.

Globally-constrained classical fields provide a unexplored framework for
modeling quantum phenomena, including apparent particle-like behavior. By
allowing controllable constraints on unknown past fields, these models are
retrocausal but not retro-signaling, respecting the conventional block universe
viewpoint of classical spacetime. Several example models are developed that
resolve the most essential problems with using classical electromagnetic fields

The Kochen-Specker theorem is a basic and fundamental 50 year old
non-existence result affecting the foundations of quantum mechanix, strongly
implying the lack of any meaningful notion of "quantum realism", and typically
leading to discussions of "contextuality" in quantum physics. Original proofs
of the Kochen-Specker theorem proceeded via brute force counter-examples; often
quite complicated and subtle (albeit mathematically "elementary")
counter-examples. Only more recently have somewhat more "geometrical" proofs