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We introduce an approach to find the Tomita-Takesaki modular flow for
multi-component regions in chiral conformal field theory. Our method is based
only locality (or braid-relations) of primary fields and the so-called
Kubo-Martin-Schwinger (KMS) condition. These methods can be used to transform
the problem to a Riemann-Hilbert problem on a covering of the complex plane cut
along the regions. The method for instance gives a formula for the modular flow
in the case of a thermal state for the free fermion net, but is in principle

In compressed sensing one uses known structures of otherwise unknown signals
to recover them from as few linear observations as possible. The structure
comes in form of some compressibility including different notions of sparsity
and low rankness. In many cases convex relaxations allow to efficiently solve
the inverse problems using standard convex solvers at almost-optimal sampling
rates. A standard practice to account for multiple simultaneous structures in

Nuclear spins in the solid state have long been envisaged as a platform for
quantum computing, due to their long coherence times and excellent
controllability. Measurements can be performed via localised electrons, for
example those in single atom dopants or crystal defects. However, establishing
long-range interactions between multiple dopants or defects is challenging.
Conversely, in lithographically-defined quantum dots, tuneable interdot
electron tunnelling allows direct coupling of electron spin-based qubits in

We discuss the relation between entanglement and nonlocality in the hidden
nonlocality scenario. Hidden nonlocality signifies nonlocality that can be
activated by applying local filters to a particular state that admits a local
hidden-variable model in the Bell scenario. We present a fully-biseparable
three-qubit bound entangled state with a local model for the most general
(non-sequential) measurements. This proves for the first time that bound
entangled states can admit a local model for general measurements. We

We study the relation between the emergence of objectivity and
qubit-environment entanglement generation. We find that although entanglement
with the unobserved environments is irrelevant (since sufficiently strong
decoherence can occur regardless), entanglement with the observed environments
is crucial. In fact, the appearance of an objective qubit-observed-environment
state is strictly impossible if their joint evolution does not lead to
entanglement. Furthermore, if a single observer has access to a single

We theoretically investigate the possibility of performing high precision
estimation of an externally imposed acceleration using scalar bosons in a
single-well trap. We work at the level of a two-mode truncation, valid for weak
to intermediate two-body interaction couplings.The splitting process into two
modes is in our model entirely caused by the interaction between the
constituent bosons and is hence neither due to an externally imposed
double-well potential nor due to populating a spinor degree of freedom. The

We study the quasiparticle excitation and quench dynamics of the
one-dimensional transverse-field Ising model with power-law ($1/r^{\alpha}$)
interactions. We find that long-range interactions give rise to a confining
potential, which couples pairs of domain walls (kinks) into bound
quasiparticles, analogous to mesonic bound states in high-energy physics. We
show that these quasiparticles have signatures in the dynamics of order
parameters following a global quench and the Fourier spectrum of these order

We propose, in a Ramsey interferometer, to cool the cavity field to its
ground state, starting from a thermal distribution by a dispersive atom-field
coupling followed by an atomic postselection. We also analyze the effect of the
cavity and atomic losses. The proposed experiment can be realized with
realistic parameters with high fidelity.

We consider energetics of a free quantum Brownian particle coupled to
thermostat of temperature $T$ and study this problem in terms of the lately
formulated quantum analogue of the energy equipartition theorem. We show how
this quantum counterpart can be derived from the Callen-Welton
fluctuation-dissipation relation and rephrased in terms of superstatistics. We
analyse the influence of the system-thermostat coupling strength and the memory
time of the dissipation kernel on statistical characteristics of the particle

Dipolar interactions are ubiquitous in nature and rule the behavior of a
broad range of systems spanning from energy transfer in biological systems to
quantum magnetism. Here, we study magnetization-conserving dipolar induced
spin-exchange dynamics in dense arrays of fermionic erbium atoms confined in a
deep three-dimensional lattice. Harnessing the special atomic properties of
erbium, we demonstrate control over the spin dynamics by tuning the dipole
orientation and changing the initial spin state within the large 20 spin

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