Quantum advantage by relational queries about physically realizable equivalence classes

Relational quantum queries are sometimes capable to effectively decide between collections of mutually exclusive elementary cases without completely resolving and determining those individual instances. Thereby the set of mutually exclusive elementary cases is effectively partitioned into equivalence classes pertinent to the respective query. In the second part of the paper, we review recent progress in theoretical certifications (relative to the assumptions made) of quantum value indeterminacy as a means to build quantum oracles for randomness.Comment: 8 Pages, one figure, invited contribution to TopHPC2019, Tehran, Iran, April 22-25, 201

Religious Struggles after Typhoon Haiyan: A case study from Bantayan Island

PURPOSE: This paper examines religious struggles and loss of faith in Christian survivors of Typhoon Haiyan in the Philippines and explores whether any demographic characteristics or experiences during the disaster may have contributed to these responses. DESIGN/METHODOLOGY/APPROACH: A quantitative survey was used to assess a variety of concepts related to religious responses after disaster. Data were collected using a mix of non-random, convenience sampling methods, with a total sample of 1,929 responses. FINDINGS: Religious struggles, anger towards God, and apostasy after the typhoon was generally low, although a significant minority of respondents expressed feelings of confusion about God and wondered whether God cared about them. Factors that influenced the experience of religious struggles included: education level, socio-economic status, denomination, barangay, loss of loved ones in the disaster, format of post-disaster church fellowship meetings, and the importance of God in their lives prior to the disaster. PRACTICAL IMPLICATIONS: Having an appropriate and supportive faith-based environment for those of faith to work through religious struggles is important for supporting emotional and psychological recovery after disaster. ORIGINALITY/VALUE: This study explores how disasters can impact individuals’ beliefs and their relationship with God in a non-Western context. This information enhances our understanding on how humanitarian and faith-based organizations can help support emotional and psychological recovery among impacted populations, particularly those who experience struggles

The Road to Quantum Computational Supremacy

We present an idiosyncratic view of the race for quantum computational supremacy. Google's approach and IBM challenge are examined. An unexpected side-effect of the race is the significant progress in designing fast classical algorithms. Quantum supremacy, if achieved, won't make classical computing obsolete.Comment: 15 pages, 1 figur

Techniques for Arbuscular Mycorrhiza Inoculum Reduction

It is well established that arbuscular mycorrhizal (AM) fungi can play a significant role in sustainable crop production and environmental conservation. With the increasing awareness of the ecological significance of mycorrhizas and their diversity, research needs to be directed away from simple records of their occurrence or casual speculation of their function (Smith and Read 1997). Rather, the need is for empirical studies and investigations of the quantitative aspects of the distribution of different types and their contribution to the function of ecosystems. There is no such thing as a fungal effect or a plant effect, but there is an interaction between both symbionts. This results from the AM fungi and plant community size and structure, soil and climatic conditions, and the interplay between all these factors (Kahiluoto et al. 2000). Consequently, it is readily understood that it is the problems associated with methodology that limit our understanding of the functioning and effects of AM fungi within field communities. Given the ubiquous presence of AM fungi, a major constraint to the evaluation of the activity of AM colonisation has been the need to account for the indigenous soil native inoculum. This has to be controlled (i.e. reduced or eliminated) if we are to obtain a true control treatment for analysis of arbuscular mycorrhizas in natural substrates. There are various procedures possible for achieving such an objective, and the purpose of this chapter is to provide details of a number of techniques and present some evaluation of their advantages and disadvantages. Although there have been a large number of experiments to investigated the effectiveness of different sterilization procedures for reducing pathogenic soil fungi, little information is available on their impact on beneficial organisms such as AM fungi. Furthermore, some of the techniques have been shown to affect physical and chemical soil characteristics as well as eliminate soil microorganisms that can interfere with the development of mycorrhizas, and this creates difficulties in the interpretation of results simply in terms of possible mycorrhizal activity. An important subject is the differentiation of methods that involve sterilization from those focussed on indigenous inoculum reduction. Soil sterilization aims to destroy or eliminate microbial cells while maintaining the existing chemical and physical characteristics of the soil (Wolf and Skipper 1994). Consequently, it is often used for experiments focussed on specific AM fungi, or to establish a negative control in some other types of study. In contrast, the purpose of inoculum reduction techniques is to create a perturbation that will interfere with mycorrhizal formation, although not necessarily eliminating any component group within the inoculum. Such an approach allows the establishment of different degrees of mycorrhizal formation between treatments and the study of relative effects. Frequently the basic techniques used to achieve complete sterilization or just an inoculum reduction may be similar but the desired outcome is accomplished by adjustments of the dosage or intensity of the treatment. The ultimate choice of methodology for establishing an adequate non-mycorrhizal control depends on the design of the particular experiments, the facilities available and the amount of soil requiring treatment

Current status of NLTE analysis of stellar atmospheres

Various available codes for NLTE modeling and analysis of hot star spectra are reviewed. Generalizations of standard equations of kinetic equilibrium and their consequences are discussed.Comment: in Determination of Atmospheric Parameters of B-, A-, F- and G-Type Stars, E. Niemczura et al. eds., Springer, in pres

Cooling a nanomechanical resonator with quantum back-action

Quantum mechanics demands that the act of measurement must affect the measured object. When a linear amplifier is used to continuously monitor the position of an object, the Heisenberg uncertainty relationship requires that the object be driven by force impulses, called back-action. Here we measure the back-action of a superconducting single-electron transistor (SSET) on a radiofrequency nanomechanical resonator. The conductance of the SSET, which is capacitively coupled to the resonator, provides a sensitive probe of the latter's position;back-action effects manifest themselves as an effective thermal bath, the properties of which depend sensitively on SSET bias conditions. Surprisingly, when the SSET is biased near a transport resonance, we observe cooling of the nanomechanical mode from 550mK to 300mK-- an effect that is analogous to laser cooling in atomic physics. Our measurements have implications for nanomechanical readout of quantum information devices and the limits of ultrasensitive force microscopy (such as single-nuclear-spin magnetic resonance force microscopy). Furthermore, we anticipate the use of these backaction effects to prepare ultracold and quantum states of mechanical structures, which would not be accessible with existing technology.Comment: 28 pages, 7 figures; accepted for publication in Natur

Finite-size and correlation-induced effects in Mean-field Dynamics

The brain's activity is characterized by the interaction of a very large number of neurons that are strongly affected by noise. However, signals often arise at macroscopic scales integrating the effect of many neurons into a reliable pattern of activity. In order to study such large neuronal assemblies, one is often led to derive mean-field limits summarizing the effect of the interaction of a large number of neurons into an effective signal. Classical mean-field approaches consider the evolution of a deterministic variable, the mean activity, thus neglecting the stochastic nature of neural behavior. In this article, we build upon two recent approaches that include correlations and higher order moments in mean-field equations, and study how these stochastic effects influence the solutions of the mean-field equations, both in the limit of an infinite number of neurons and for large yet finite networks. We introduce a new model, the infinite model, which arises from both equations by a rescaling of the variables and, which is invertible for finite-size networks, and hence, provides equivalent equations to those previously derived models. The study of this model allows us to understand qualitative behavior of such large-scale networks. We show that, though the solutions of the deterministic mean-field equation constitute uncorrelated solutions of the new mean-field equations, the stability properties of limit cycles are modified by the presence of correlations, and additional non-trivial behaviors including periodic orbits appear when there were none in the mean field. The origin of all these behaviors is then explored in finite-size networks where interesting mesoscopic scale effects appear. This study leads us to show that the infinite-size system appears as a singular limit of the network equations, and for any finite network, the system will differ from the infinite system

Reinforcement learning or active inference?

This paper questions the need for reinforcement learning or control theory when optimising behaviour. We show that it is fairly simple to teach an agent complicated and adaptive behaviours using a free-energy formulation of perception. In this formulation, agents adjust their internal states and sampling of the environment to minimize their free-energy. Such agents learn causal structure in the environment and sample it in an adaptive and self-supervised fashion. This results in behavioural policies that reproduce those optimised by reinforcement learning and dynamic programming. Critically, we do not need to invoke the notion of reward, value or utility. We illustrate these points by solving a benchmark problem in dynamic programming; namely the mountain-car problem, using active perception or inference under the free-energy principle. The ensuing proof-of-concept may be important because the free-energy formulation furnishes a unified account of both action and perception and may speak to a reappraisal of the role of dopamine in the brain

An effective theory for jet propagation in dense QCD matter: jet broadening and medium-induced bremsstrahlung

Two effects, jet broadening and gluon bremsstrahlung induced by the propagation of a highly energetic quark in dense QCD matter, are reconsidered from effective theory point of view. We modify the standard Soft Collinear Effective Theory (SCET) Lagrangian to include Glauber modes, which are needed to implement the interactions between the medium and the collinear fields. We derive the Feynman rules for this Lagrangian and show that it is invariant under soft and collinear gauge transformations. We find that the newly constructed theory SCET$_{\rm G}$ recovers exactly the general result for the transverse momentum broadening of jets. In the limit where the radiated gluons are significantly less energetic than the parent quark, we obtain a jet energy-loss kernel identical to the one discussed in the reaction operator approach to parton propagation in matter. In the framework of SCET$_{\rm G}$ we present results for the fully-differential bremsstrahlung spectrum for both the incoherent and the Landau-Pomeranchunk-Migdal suppressed regimes beyond the soft-gluon approximation. Gauge invariance of the physics results is demonstrated explicitly by performing the calculations in both the light-cone and covariant $R_{\xi}$ gauges. We also show how the process-dependent medium-induced radiative corrections factorize from the jet production cross section on the example of the quark jets considered here.Comment: 52 pages, 15 pdf figures, as published in JHE

Insecticidal Activity of the Essential Oils from Different Plants Against Three Stored-Product Insects

This study was conducted to determine the insecticidal activity of essential oils from oregano, Origanum onites L. (Lamiales: Lamiaceae), savory, Satureja thymbra L. (Lamiales: Lamiaceae), and myrtle, Myrtus communis L. (Rosales: Myrtaceae) against three stored-product insects. Essential oils from three species of plants were obtained by Clevenger-type water distillation. The major compounds in these essential oils were identified using gas chromatography-mass spectrometry and their insecticidal activity was tested against adults of the Mediterranean flour moth Ephestia kuehniella Zeller (Lepidoptera: Pyralidae), the Indian meal moth Plodia interpunctella Hübner (Lepidoptera: Pyralidae) and the bean weevil Acanthoscelides obtectus Say (Coleoptera: Bruchidae). While the major compound found in oregano and savory was carvacrol, the main constituent of the myrtle was linalool. Among the tested insects, A. obtectus was the most tolerant species against the essential oils. However, the insecticidal activity of the myrtle oil was more pronounced than other oils tested against A. obtectus adults. The essential oils of oregano and savory were highly effective against P. interpunctella and E. kuehniella, with 100% mortality obtained after 24 h at 9 and 25 µl/l air for P. interpunctella and E. kuehniella, respectively. LC50 and LC99 values of each essential oil were estimated for each insect species