Quality of life in parents of young adults with ASD : EpiTED cohort

The impact of ASD on parental QOL was evaluated in the EpiTED cohort study at early adulthood. Two-third of parents of young adults with ASD (66.7%) reported that their QoL was at least moderately altered. The perceived impact of ASD on parental QoL was related to the young adults' level of adaptive skills, as well as to symptom severity and the presence of challenging behaviors, which appeared to be the main risk factor. The study of change between adolescence and early adulthood showed that parents whose children had a decrease in challenging behaviors perceived a decreased impact on their QoL. These results argue for the importance to propose specific interventions to target associated challenging behaviors in ASD

Block Renormalization for quantum Ising models in dimension d=2d=2 : applications to the pure and random ferromagnet, and to the spin-glass

For the quantum Ising chain, the self-dual block renormalization procedure of Fernandez-Pacheco [Phys. Rev. D 19, 3173 (1979)] is known to reproduce exactly the location of the zero-temperature critical point and the correlation length exponent $\nu=1$. Recently, Miyazaki and Nishimori [Phys. Rev. E 87, 032154 (2013)] have proposed to study the disordered quantum Ising model in dimensions $d>1$ by applying the Fernandez-Pacheco procedure successively in each direction. To avoid the inequivalence of directions of their approach, we propose here an alternative procedure where the $d$ directions are treated on the same footing. For the pure model, this leads to the correlation length exponents $\nu \simeq 0.625$ in $d=2$ (to be compared with the 3D classical Ising model exponent $\nu \simeq 0.63$) and $\nu \simeq 0.5018$ (to be compared with the 4D classical Ising model mean-field exponent $\nu =1/2$). For the disordered model in dimension $d=2$, either ferromagnetic or spin-glass, the numerical application of the renormalization rules to samples of linear size $L=4096$ yields that the transition is governed by an Infinite Disorder Fixed Point, with the activated exponent $\psi \simeq 0.65$, the typical correlation exponent $\nu_{typ} \simeq 0.44$ and the finite-size correlation exponent $\nu_{FS} \simeq 1.25$. We discuss the similarities and differences with the Strong Disorder Renormalization results.Comment: v2=final version (21 pages, 6 figures

Low-temperature dynamics of Long-Ranged Spin-Glasses : full hierarchy of relaxation times via real-space renormalization

We consider the long-ranged Ising spin-glass with random couplings decaying as a power-law of the distance, in the region of parameters where the spin-glass phase exists with a positive droplet exponent. For the Metropolis single-spin-flip dynamics near zero temperature, we construct via real-space renormalization the full hierarchy of relaxation times of the master equation for any given realization of the random couplings. We then analyze the probability distribution of dynamical barriers as a function of the spatial scale. This real-space renormalization procedure represents a simple explicit example of the droplet scaling theory, where the convergence towards local equilibrium on larger and larger scales is governed by a strong hierarchy of activated dynamical processes, with valleys within valleys.Comment: v2=final versio

Dyson hierarchical quantum ferromagnetic Ising chain with pure or random transverse fields

The Dyson hierarchical version of the quantum Ising chain with Long-Ranged power-law ferromagnetic couplings $J(r) \propto r^{-1-\sigma}$ and pure or random transverse fields is studied via real-space renormalization. For the pure case, the critical exponents are explicitly obtained as a function of the parameter $\sigma$, and are compared with previous results of other approaches. For the random case, the RG rules are numerically applied and the critical behaviors are compared with previous Strong Disorder Renormalization results.Comment: 21 pages, 4 figures, v2=final versio

Star junctions and watermelons of pure or random quantum Ising chains : finite-size properties of the energy gap at criticality

We consider $M \geq 2$ pure or random quantum Ising chains of $N$ spins when they are coupled via a single star junction at their origins or when they are coupled via two star junctions at the their two ends leading to the watermelon geometry. The energy gap is studied via a sequential self-dual real-space renormalization procedure that can be explicitly solved in terms of Kesten variables containing the initial couplings and and the initial transverse fields. In the pure case at criticality, the gap is found to decay as a power-law $\Delta_M \propto N^{-z(M)}$ with the dynamical exponent $z(M)=\frac{M}{2}$ for the single star junction (the case $M=2$ corresponds to $z=1$ for a single chain with free boundary conditions) and $z(M)=M-1$ for the watermelon (the case $M=2$ corresponds to $z=1$ for a single chain with periodic boundary conditions). In the random case at criticality, the gap follows the Infinite Disorder Fixed Point scaling $\ln \Delta_M = -N^{\psi} g$ with the same activated exponent $\psi=\frac{1}{2}$ as the single chain corresponding to $M=2$, and where $g$ is an $O(1)$ random positive variable, whose distribution depends upon the number $M$ of chains and upon the geometry (star or watermelon).Comment: 14 page

Ignorance, Humility and Vice

LaFollette argues that the greatest vice is not cruelty, immorality, or selfishness. Rather, it is a failure on our part to ‘engage in frequent, honest and rigorous self-reflection’. It is that failure which, on his view, explains the lion’s share of the wrongdoings we commit towards one another. In this short reply, I raise (in a sympathetic spirit) some questions about the task of identifying the greatest vice, and draw out some of the implications of LaFollette’s account of moral ignorance

Level repulsion exponent β\beta for Many-Body Localization Transitions and for Anderson Localization Transitions via Dyson Brownian Motion

The generalization of the Dyson Brownian Motion approach of random matrices to Anderson Localization (AL) models [Chalker, Lerner and Smith PRL 77, 554 (1996)] and to Many-Body Localization (MBL) Hamiltonians [Serbyn and Moore arxiv:1508.07293] is revisited to extract the level repulsion exponent $\beta$, where $\beta=1$ in the delocalized phase governed by the Wigner-Dyson statistics, $\beta=0$ in the localized phase governed by the Poisson statistics, and $0<\beta_c<1$ at the critical point. The idea is that the Gaussian disorder variables $h_i$ are promoted to Gaussian stationary processes $h_i(t)$ in order to sample the disorder stationary distribution with some time correlation $\tau$. The statistics of energy levels can be then studied via Langevin and Fokker-Planck equations. For the MBL quantum spin Hamiltonian with random fields $h_i$, we obtain $\beta =2q^{EA}_{n,n+1}(N)/q^{EA}_{n,n}(N)$ in terms of the Edwards-Anderson matrix $q^{EA}_{nm}(N) \equiv \frac{1}{N} \sum_{i=1}^N | |^2$ for the same eigenstate $m=n$ and for consecutive eigenstates $m=n+1$. For the Anderson Localization tight-binding Hamiltonian with random on-site energies $h_i$, we find $\beta =2 Y_{n,n+1}(N)/(Y_{n,n}(N)-Y_{n,n+1}(N))$ in terms of the Density Correlation matrix $Y_{nm}(N) \equiv \sum_{i=1}^N | |^2 | |^2$ for consecutive eigenstates $m=n+1$, while the diagonal element $m=n$ corresponds to the Inverse Participation Ratio $Y_{nn}(N) \equiv \sum_{i=1}^N | |^4$ of the eigenstate $| \phi_n>$.Comment: 22 page

In Defence of Mercenarism

The recent wars in Iraq and Afghanistan have been characterized by the deployment of large private military forces, under contract with the US administration. The use of so-called private military corporations (PMCs) and, more generally, of mercenaries, has long attracted criticisms. This article argues that under certain conditions (drawn from the Just War tradition), there is nothing inherently objectionable about mercenarism. It begins by exposing a weakness in the most obvious justification for mercenarism, to wit, the justification from freedom of occupational choice. It then deploys a less obvious, but stronger, argument – one that appeals to the importance of enabling just defensive killings. Finally, it rebuts five moral objections to mercenarism.</jats:p

Why stop at two tops? Search for exotic production of top quarks in final states with same-sign leptons and bb-jets at 13 TeV

An analysis is presented of events containing jets including at least one $b$-tagged jet, sizable missing transverse momentum, and at least two charged leptons including a pair of the same electric charge, with the scalar sum of the jet and lepton transverse momenta being large. Standard Model processes rarely produce these final states, but several models of physics beyond the Standard Model predict an enhanced production rate of such events. Specific models with this feature are considered here: vector-like $T$, $B$, and $T_{5/3}$ quark pair production, and four top quark production under three scenarios (Standard Model, contact interaction, and extra-dimensions). A data sample of 3.2 fb$^{-1}$ of $pp$ collisions at a center-of-mass energy of $\sqrt{s}$=13 TeV recorded by the ATLAS detector at the Large Hadron Collider is used in this analysis. Several signal regions are defined, in which the consistency between the data yield and the background-only hypothesis is checked, and 95% confidence level limits are set on various signal models. The focus here is on models yielding signatures with four top quarks.Comment: 5 pages, 5 figures, contribution to the proceedings of the 9th International Workshop on Top Quark Physics (TOP 2016), Olomouc, Czech Republic, September 19-23, 201