Phenomenology of SUSY with scalar sequestering

The defining feature of scalar sequestering is that the MSSM squark and slepton masses as well as all entries of the scalar Higgs mass matrix vanish at some high scale. This ultraviolet boundary condition - scalar masses vanish while gaugino and Higgsino masses are unsuppressed - is independent of the supersymmetry breaking mediation mechanism. It is the result of renormalization group scaling from approximately conformal strong dynamics in the hidden sector. We review the mechanism of scalar sequestering and prove that the same dynamics which suppresses scalar soft masses and the B_mu term also drives the Higgs soft masses to -|mu|^2. Thus the supersymmetric contribution to the Higgs mass matrix from the mu-term is exactly canceled by the soft masses. Scalar sequestering has two tell-tale predictions for the superpartner spectrum in addition to the usual gaugino mediation predictions: Higgsinos are much heavier (mu > TeV) than scalar Higgses (m_A ~ few hundred GeV), and third generation scalar masses are enhanced because of new positive contributions from Higgs loops.Comment: 16 pages and 3 figure

The general structure of quantum resource theories

In recent years it was recognized that properties of physical systems such as entanglement, athermality, and asymmetry, can be viewed as resources for important tasks in quantum information, thermodynamics, and other areas of physics. This recognition followed by the development of specific quantum resource theories (QRTs), such as entanglement theory, determining how quantum states that cannot be prepared under certain restrictions may be manipulated and used to circumvent the restrictions. Here we discuss the general structure of QRTs, and show that under a few assumptions (such as convexity of the set of free states), a QRT is asymptotically reversible if its set of allowed operations is maximal; that is, if the allowed operations are the set of all operations that do not generate (asymptotically) a resource. In this case, the asymptotic conversion rate is given in terms of the regularized relative entropy of a resource which is the unique measure/quantifier of the resource in the asymptotic limit of many copies of the state. This measure also equals the smoothed version of the logarithmic robustness of the resource.Comment: 5 pages, no figures, few references added, published versio

Qubit measurements with a double-dot detector

We propose to monitor a qubit with a double-dot (DD) resonant-tunneling detector, which can operate at higher temperatures than a single-dot detector. In order to assess the effectiveness of this device, we derive rate equations for the density matrix of the entire system. We show that the signal-to-noise ratio can be greatly improved by a proper choice of the parameters and location of the detector. We demonstrate that quantum interference effects within the DD detector play an important role in the measurement. Surprisingly, these effects produce a systematic measurement error, even when the entire system is in a stationary state.Comment: 4 pages, some explanations added, Phys. Rev. Lett., in pres

Is the Relaxion an Axion?

We consider the recently proposed cosmological relaxation mechanism where the hierarchy problem is ameliorated, and the electroweak scale is dynamically selected by a slowly rolling axion field. We argue that, in its simplest form, the construction breaks a gauge symmetry that always exists for pseudo-Nambu-Goldstone bosons (in particular the axion). The small parameter in the relaxion model is therefore not technically natural as it breaks a gauge symmetry rather than global symmetries only. The consistency of the theory generically implies that the cutoff must lie around the electroweak scale, but not qualitatively higher. We discuss several ways to evade the above conclusion. Some of them may be sufficient to increase the cutoff to the few-TeV range (and therefore may be relevant for the little-hierarchy problem). To demonstrate the ideas in a concrete setting we consider a model with a familon, the Nambu-Goldstone boson of a spontaneously broken chiral flavor symmetry. The model has some interesting collider-physics aspects and contains a viable weakly interacting dark matter candidate.Comment: some typos fixed, clarifications adde

Phenomenology of relaxion-Higgs mixing

We show that the relaxion generically stops its rolling at a point that breaks CP leading to relaxion-Higgs mixing. This opens the door to a variety of observational probes since the possible relaxion mass spans a broad range from sub-eV to the GeV scale. We derive constraints from current experiments (fifth force, astrophysical and cosmological probes, beam dump, flavour, LEP and LHC) and present projections from future experiments such as NA62, SHiP and PIXIE. We find that a large region of the parameter space is already under the experimental scrutiny. All the experimental constraints we derive are equally applicable for general Higgs portal models. In addition, we show that simple multiaxion (clockwork) UV completions suffer from a mild fine tuning problem, which increases with the number of sites. These results favour a cut-off scale lower than the existing theoretical bounds.Comment: 46 pages, 6 figures, v3: typos fixed, references added, version matches the version published in JHE

Lessons from Recent Measurements of D-\bar D Mixing

An impressive progress in measurements of the D-\bar D mixing parameters has been made in recent years. We explore the implications of these measurements to models of new physics, especially in view of recent upper bounds on the amount of CP violation. We update the constraints on non-renormalizable four-quark operators. We show that the experiments are close to probing minimally flavor violating models with large tan beta. The data challenge models with a scale of order TeV where the flavor violation in the down sector is suppressed by alignment and, in particular, certain classes of supersymmetric models and of warped extra dimension models.Comment: 20 pages, 1 figure. Added references, minor corrections and clarifications. Matches published versio

Compromise in negotiation: exploiting worth functions over states

AbstractPrevious work by G. Zlotkin and J.S. Rosenschein (1989, 1990, 1991, 1992) discussed interagent negotiation protocols. One of the main assumptions there was that the agents' goals remain fixed—the agents cannot relax their initial goals, which can be achieved only as a whole and cannot be partially achieved. A goal there was considered a formula that is either satisfied or not satisfied by a given state.We here present a more general approach to the negotiation problem in non-cooperative domains where agents' goals are not expressed as formulas, but rather as worth functions. An agent associates a particular value with each possible final state; this value reflects the degree of satisfaction the agent derives from being in that state.With this new definition of goal as worth function, an agreement may lead to a situation in which one or both goals are only partially achieved (i.e., agents may not reach their most desired state). We present a negotiation protocol that can be used in a general non-cooperative domain when worth functions are available. This multi-plan deal type allows agents to compromise over their degree of satisfaction, and (in parallel) to negotiate over the joint plan that will be implemented to reach the compromise final state. The ability to compromise often results in a better deal, enabling agents to increase their overall utility.Finally, we present more detailed examples of specific worth functions in various domains, and show how they are used in the negotiation process

Undersampled Phase Retrieval with Outliers

We propose a general framework for reconstructing transform-sparse images from undersampled (squared)-magnitude data corrupted with outliers. This framework is implemented using a multi-layered approach, combining multiple initializations (to address the nonconvexity of the phase retrieval problem), repeated minimization of a convex majorizer (surrogate for a nonconvex objective function), and iterative optimization using the alternating directions method of multipliers. Exploiting the generality of this framework, we investigate using a Laplace measurement noise model better adapted to outliers present in the data than the conventional Gaussian noise model. Using simulations, we explore the sensitivity of the method to both the regularization and penalty parameters. We include 1D Monte Carlo and 2D image reconstruction comparisons with alternative phase retrieval algorithms. The results suggest the proposed method, with the Laplace noise model, both increases the likelihood of correct support recovery and reduces the mean squared error from measurements containing outliers. We also describe exciting extensions made possible by the generality of the proposed framework, including regularization using analysis-form sparsity priors that are incompatible with many existing approaches.Comment: 11 pages, 9 figure