Do the gravitational corrections to the beta functions of the quartic and Yukawa couplings have an intrinsic physical meaning?

We study the beta functions of the quartic and Yukawa couplings of General Relativity and Unimodular Gravity coupled to the $\lambda\phi^4$ and Yukawa theories with masses. We show that the General Relativity corrections to those beta functions as obtained from the 1PI functional by using the standard MS multiplicative renormalization scheme of Dimensional Regularization are gauge dependent and, further, that they can be removed by a non-multiplicative, though local, field redefinition. An analogous analysis is carried out when General Relativity is replaced with Unimodular Gravity. Thus we show that any claim made about the change in the asymptotic behaviour of the quartic and Yukawa couplings made by General Relativity and Unimodular Gravity lack intrinsic physical meaning.Comment: 6 pages, 7 figure

Non-linear Symmetry-preserving Observer on Lie Groups

In this paper we give a geometrical framework for the design of observers on finite-dimensional Lie groups for systems which possess some specific symmetries. The design and the error (between true and estimated state) equation are explicit and intrinsic. We consider also a particular case: left-invariant systems on Lie groups with right equivariant output. The theory yields a class of observers such that error equation is autonomous. The observers converge locally around any trajectory, and the global behavior is independent from the trajectory, which reminds of the linear stationary case.Comment: 12 pages. Submitted. Preliminary version publicated in french in the CIFA proceedings and IFAC0

When adolescents stop psychological therapy: rupture-repair in the therapeutic alliance and association with therapy ending

therapeutic alliance consistently predicts dropout from psychological therapy, and ruptures in the therapeutic alliance may also predict dropout, yet there is a dearth of research with adolescents. This study investigated whether markers of rupturerepair in the therapeutic alliance were indicative of different types of treatment ending in adolescents who received psychological treatment for depression. Data were from the IMPACT study, a trial investigating the effectiveness of therapies for adolescent depression. Participants were randomly allocated to receive a psychological therapy: Brief Psychosocial Intervention, Cognitive-Behavioural Therapy or Short-Term Psychoanalytic Psychotherapy. The sample (N=35) comprised adolescents who had either completed their treatment (n=14) or dropped out (n=21) according to their therapist. Dropout cases were further classified as dissatisfied (n=14) or got-whatthey- needed (n=7) based on post-therapy interviews with the adolescent and therapist. Selected audio-recordings of therapy sessions were rated using the Rupture Resolution Rating System and Working Alliance Inventory (observer-version). Therapeutic alliance and rupture-repair during therapy were similar for completers and got-what-they-needed dropouts, while dissatisfied dropouts had poorer therapeutic alliance, more ruptures, ruptures were frequently unresolved, and therapists contributed to ruptures to a greater extent. Qualitative analysis of the sessions led to the construction of three categories of therapist contribution to ruptures: therapist minimal response; persisting with a therapeutic activity; and focus on risk. Results suggest that ruptures, especially when unresolved, could be regarded as warning signs of disengagement and dropout from psychological treatment. Future research should investigate how ruptures may be effectively identified and resolved in treatment with adolescents

Symmetry-preserving Observers

This paper presents three non-linear observers on three examples of engineering interest: a chemical reactor, a non-holonomic car, and an inertial navigation system. For each example, the design is based on physical symmetries. This motivates the theoretical development of invariant observers, i.e, symmetry-preserving observers. We consider an observer to consist in a copy of the system equation and a correction term, and we give a constructive method (based on the Cartan moving-frame method) to find all the symmetry-preserving correction terms. They rely on an invariant frame (a classical notion) and on an invariant output-error, a less standard notion precisely defined here. For each example, the convergence analysis relies also on symmetries consideration with a key use of invariant state-errors. For the non-holonomic car and the inertial navigation system, the invariant state-errors are shown to obey an autonomous differential equation independent of the system trajectory. This allows us to prove convergence, with almost global stability for the non-holonomic car and with semi-global stability for the inertial navigation system. Simulations including noise and bias show the practical interest of such invariant asymptotic observers for the inertial navigation system.Comment: To be published in IEEE Automatic Contro

Identifying capacitive and inductive loss in lumped element superconducting hybrid titanium nitride/aluminum resonators

We present a method to systematically locate and extract capacitive and inductive losses in superconducting resonators at microwave frequencies by use of mixed-material, lumped element devices. In these devices, ultra-low loss titanium nitride was progressively replaced with aluminum in the inter-digitated capacitor and meandered inductor elements. By measuring the power dependent loss at 50 mK as the Al-TiN fraction in each element is increased, we find that at low electric field, i.e. in the single photon limit, the loss is two level system in nature and is correlated with the amount of Al capacitance rather than the Al inductance. In the high electric field limit, the remaining loss is linearly related to the product of the Al area times its inductance and is likely due to quasiparticles generated by stray radiation. At elevated temperature, additional loss is correlated with the amount of Al in the inductance, with a power independent TiN-Al interface loss term that exponentially decreases as the temperature is reduced. The TiN-Al interface loss is vanishingly small at the 50 mK base temperature.Comment: 10 pages, 5 figure

On Lorentz-Violating Supersymmetric Quantum Field Theories

We study the possibility of constructing Lorentz-violating supersymmetric quantum field theories under the assumption that these theories have to be described by lagrangians which are renormalizable by weighted power counting. Our investigation starts from the observation that at high energies Lorentz-violation and the usual supersymmetry algebra are algebraically compatible. Demanding linearity of the supercharges we see that the requirement of renormalizability drastically restricts the set of possible Lorentz-violating supersymmetric theories. In particular, in the case of supersymmetric gauge theories the weighted power counting has to coincide with the usual one and the only Lorentz-violating operators are introduced by some weighted constant c that explicitly appears in the supersymmetry algebra. This parameter does not renormalize and has to be very close to the speed of light at low energies in order to satisfy the strict experimental bounds on Lorentz violation. The only possible models with non trivial Lorentz-violating operators involve neutral chiral superfields and do not have a gauge invariant extension. We conclude that, under the assumption that high-energy physics can be described by a renormalizable Lorentz-violating extensions of the Standard Model, the Lorentz fine tuning problem does not seem solvable by the requirement of supersymmetry.Comment: 22 pages, 2 figure