Seeing the entanglement wedge

We study the problem of revealing the entanglement wedge using simple operations. We ask what operation a semiclassical observer can do to bring the entanglement wedge into causal contact with the boundary, via backreaction.In a generic perturbative class of states, we propose a unitary operation in the causal wedge whose backreaction brings all of the previously causally inaccessible ‘peninsula’ into causal contact with the boundary. This class of cases includes entanglement wedges associated to boundary sub-regions that are unions of disjoint spherical caps, and the protocol works to first order in the size of the peninsula. The unitary is closely related to the so-called Connes Cocycle flow, which is a unitary that is both well-defined in QFT and localised to a sub-region. Our construction requires a generalization of the work by Ceyhan & Faulkner to regions which are unions of disconnected spherical caps. We discuss this generalization in the appendix. We argue that this cocycle should be thought of as naturally generalizing the non-local coupling introduced in the work of Gao, Jafferis & Wall.

An endogenous basis for synchronization manners of the circadian rhythm in proliferating Lemna minor plants

Endogenous circadian rhythms in plants play a role in adaptation to day-night cycles. The circadian clock is a cell-autonomous system that functions through the coordination of time information in the plant body. Synchronization of cellular clocks is based on coordination mechanisms; the synchronization manners in proliferating plants remain unclear. We performed spatiotemporal analysis of the circadian rhythm of fronds (leaf-like plant units) of proliferating Lemna minor plants carrying a circadian bioluminescence reporter, AtCCA1:LUC. Noninvasive observations of the bioluminescence of fast-growing two-dimensional plants allowed us to analyze the circadian rhythms at a cell-level resolution and obtain information regarding frond lineage. We focused on spontaneous circadian organization under constant light conditions for plants with light/dark treatment (LD-grown) or without it (LL-grown). Even fronds developing from an LL-grown parental frond showed coherent circadian rhythms among them. This allowed the maintenance of circadian rhythmicity in proliferating plants. Inside a frond, a centrifugal phase/period pattern was observed in LD-grown plants, whereas various phase patterns with traveling waves were formed in LL-grown plants. These patterns were model-simulated by local coupling of cellular circadian oscillators with different initial synchronous states in fronds. Taken together with similar patterning previously reported for detached leaves of Arabidopsis, it is strongly suggested that local coupling is the primary force for the development of these phase patterns in plants lacking long-distance communication. We propose a basic framework of spontaneous phase patterning with three stages of circadian organization: initial phasing, evolution of patterning, and desynchronization/randomizing of phase, in association with altering cell-cell coupling.

Investigation of DNA Breather Dynamics in A Model with Non-Local Inter-Site Interaction

A variant of the Peyrard-Bishop-Dauxois model is proposed, which takes account of the partially delocalized nature of DNA stacking interactions. It is shown that the nonlocal nature of the inter-site potential can lead to an increase in the local cooperativity of the base pairs' opening an increasing in the number of simultaneously opening adjacent nucleotide pairs during the denaturation bubble's nucleation. The process of the formation and propagation of mobile breathers excited by the initial displacements of a number of nucleotide pairs has been studied. It is revealed that taking account of the non-local coupling in the Peyrard-Bishop-Dauxois model, while maintaining the remaining parameters of the model, leads to a decrease in the speed of the mobile breather and an increase in the probability of nucleation of the denaturation bubble.

Effect of Inter-Well Interactions on Non-Linear Beam Splitters for Matter-Wave Interferometers

We study the non-linear beam splitter in matter-wave interferometers using ultracold quantum gases in a double-well configuration in presence of non-local interactions inducing inter-well density-density coupling, as they can be realized, e.g., with dipolar gases. We explore this effect after considering different input states, in the form of either coherent, or Twin-Fock, or NOON states. We first review the non-interacting limit and the case in which only the local interaction is present, including the study of sensitivity near the self-trapping threshold. Then, we consider the two-mode model in the presence of inter-well interactions and consider the scaling of the sensitivity as a function of the non-local coupling strength. Our analysis clearly shows that non-local interactions can compensate the degradation of the sensitivity induced by local interactions, so that they may be used to restore optimal sensitivity.

Precise polyethylene derivatives bearing mesogenic side-chains: delicate self-assembly depending on graft density

Precise polyethylene derivatives bearing mesogenic side-chains demonstrate a sophisticated side-chain spacing effect on the local coupling and spatial arrangement of the backbone and side-chains.

Aster swarming by symmetry breaking of cortical dynein transport and coupling kinesins

Multiple microtubule (MT) asters in a confined cell spontaneously swarm with rotational motion due to a combination of local coupling by kinesin-5 motors, active boundary driven by cortical dynein and ‘noise’ due to stochasticity of MT lengths.

Dynamics of disordered heterogeneous chains of phase oscillators

We study the problem of robustness of synchronous states to disorder in the chain of phase oscillators with local coupling. The study combines a numerical determination of the existence and stability of synchronous states with an analytical investigation of the role of the phase shift and the level of disorder in the natural frequencies in the destruction of synchrony. We show that the presence of the phase shift facilitates robustness of the synchronous regime, at least up to its certain threshold value.