General Arguments Research Articles

Cutkosky rules and 1-loop κ -deformed amplitudes

In this paper, we show that the Cutkosky cutting rules are still valid term by term in the expansion in powers of κ of the κ-deformed 1-loop correction to the propagator of the κ-deformed complex scalar field. We first present a general argument which relates each term in the expansion to a nondeformed amplitude containing additional propagators with mass M>κ. We then show the same thing more pragmatically, by reducing the singularity structure of the coefficients in the expansion of the κ-deformed amplitude, to the singularity structure of nondeformed loop amplitudes, by using algebraic and analytic identities. We will explicitly show this up to second order in 1/κ, but the technique can be generalized to higher orders in 1/κ. Both the abstract and the more direct approach easily generalize to different deformed theories. We will then compute the full imaginary part of the κ-deformed 1-loop correction to the propagator in a specific model, up to second order in the expansion in 1/κ, highlighting the usefulness of the approach for the phenomenology of deformed models. This explicitly confirms previous qualitative arguments concerning the behavior of the decay width of unstable particles in the considered model. Published by the American Physical Society 2024

APOSENTADORIA RURAL POR IDADE E OS MEIOS DE PROVAS NECESSÁRIAS PARA A CONCESSÃO DO BENEFÍCIO DIREITO PREVIDENCIÁRIO

This work addresses the analysis of the necessary requirements for granting the rural retirement benefit to rural workers, taking into account their difficulties and facilities for granting the benefit, after the various system updates until the benefit is granted. This sets out the approach method used in this article, which will be deductive where the general arguments will be analyzed. Its objective is to analyze and understand the various situations encountered and faced by special insured persons when applying for retirement, to list the difficulties in proving their rights, which in most cases occurs through proof of facts that are not registered, and to estimate the facilities established by the National Social Security Institute (INSS), which simplify the social security administrative process. Thus, to characterize the obstacles and difficulties during the process of granting retirement by age, promoting the verification of the essential elements that make up this set of means, the changes during the administrative social security process and in the legislation regarding rural retirement by rural age, as well as the difficulty in proving the exercise of rural activity, a burden that lies with you.

Generalized Rosenfeld–Tarazona scaling and high-density specific heat of simple liquids

The original Rosenfeld–Tarazona (RT) scaling of the excess energy in simple dense fluids predicts a ∝T3/5 thermal correction to the fluid Madelung energy. This implies that the excess isochoric heat capacity scales as Cvex∝T−2/5. Careful examination performed in this paper demonstrates that the exponent −2/5 is not always optimal. For instance, in the Lennard-Jones fluid in some vicinity of the triple point, the exponent −1/3 turns out to be more appropriate. The analysis of the specific heat data in neon, argon, krypton, xenon, and liquid mercury reveals that no single value of the exponent exists, describing all the data simultaneously. Therefore, we propose a generalized RT scaling in the form Cvex∝T−α, where α is a density- and material-dependent adjustable parameter. The question concerning which material properties and parameters affect the exponent α and whether it can be predicted from general physical arguments requires further investigation.

Effects of final state interactions on Landau singularities

In certain kinematic and particle mass configurations, triangle singularities may lead to line-shapes which mimic the effects of resonances. This well-known effect is scrutinized here in the presence of final-state rescattering. The goal is achieved first by utilizing general arguments provided by Landau equations, and second by applying a modern scattering formalism with explicit two- and three-body unitarity.

Decoding the Gaugino Code Naturally at High-Lumi LHCs

Natural supersymmetry with light higgsinos is most favored to emerge from the string landscape, since the volume of a scan parameter space shrinks to tiny volumes for electroweak unnatural models. Rather general arguments favor a landscape selection of soft SUSY breaking terms tilted to large values, but they are tempered by the atomic principle that the derived value of the weak scale in each pocket universe lies not too far from its measured value in our universe. But, that leaves (at least) three different paradigms for gaugino masses in natural SUSY models: unified (as in nonuniversal Higgs models), anomaly mediation form (as in natural AMSB), and mirage mediation form (with comparable moduli- and anomaly-mediated contributions). We perform landscape scans for each of these, and we show that they populate different, but overlapping, positions in m(ℓℓ¯) and m(wino) space. The first of these may be directly measurable at high-lumi LHC via the soft opposite-sign dilepton plus jets plus E/T signature arising from higgsino pair production, while the second of these could be extracted from direct wino pair production, leading to same-sign diboson production.

Spatial resolution limit for a solid immersion lens

The solid immersion (SI) effect is widely used to increase the spatial resolution of optical focusing systems and even overcome the Abbe diffraction limit. Resolution enhancement offered by a SI lens is mostly a function of its geometry and refractive index nSI. While SI lenses are relatively well understood, the scaling of the resolution enhancement by such lenses is still a subject of debate, with some works reporting ≃nSI and ≃nSI2 dependencies for the hemispherical and hyperhemispherical SI lens configurations, respectively. In this paper, we offer a general argument for a resolution limit for SI optics and, then, verify it via the numerical analysis of the hemispherical and hyperhemispherical silicon SI lenses designed for the terahertz (THz) range. In fact, we find that there is no contradiction in the reported resolution enhancements ≃nSI and ≃nSI2; however, they happen in different operation regimes. We then demonstrate that the resolution values reported for the different SI lens arrangements in the visible (VIS), near-, and middle-infrared (NIR and MIR), as well as THz bands obey the derived limit. Our findings will be useful for the further design and applications of SI optics.

Dark energy with a shift-symmetric scalar field: Obstacles, loophole hunting and dead ends

We discuss the possibility of a scalar field being the fundamental description of dark energy. We focus on shift-symmetric scalar-tensor theories since this symmetry potentially avoids some fine-tuning problems. We also restrict attention to theories satisfying that the propagation speed of gravitational waves is equal to the speed of light. These considerations lead us to investigate shift-symmetric Kinetic Gravity Braiding theories. Analysing the stability of scalar linear perturbations, we discuss the conditions that seems to be necessary to describe (super) accelerated cosmic expansion without introducing instabilities. However, it has been previously established that the linearised analysis does not guarantee the stability of this non-canonical scalar theory, as potentially dangerous interactions between dark energy fluctuations and tensor perturbations (essentially gravitational waves) appear at a higher order in perturbation theory. Indeed, although we shall point out that the standard proof of absence of dark energy stable braiding models due to this interaction has a possible way-out, we find general arguments suggesting that there are no dark energy stable solutions that can exploit this loophole. Thus, we discuss future research directions for finding viable fundamental descriptions of dark energy. We also provide a dictionary between the covariant version of the theory and that of the Effective Field Theory approach, explicitly computing the parameters in the latter formalism in terms of the functions appearing in the covariant version, and its derivatives. To the best of our knowledge, this is the first time these expressions are explicitly obtained up-to arbitrary order in perturbation theory.

Lowering trade barriers improves income distribution and economic resiliency

The U.S.-China trade war, COVID-19 pandemic and Russian invasion of Ukraine contributed to calls for greater economic self-sufficiency by exposing gaps in international collaboration and the uncertainty of global supply chains. In this study, we apply a comprehensive global modeling framework to enhance understanding of the potential impacts of fragmentation of global value chains. Supporting the general argument toward economic benefits from open markets our analysis contributes to the policy debate in two important dimensions of this phenomenon—distributional impacts and economic resiliency. We find that tariff liberalization and trade facilitation measures implemented by developing countries could not only reduce between-country inequality but also result in progressive within-country income distribution primarily through lowering food prices, as well as increasing unskilled wages. In addition, using a case study of disruption to Thailand’s electronics industry, we find higher resiliency of developing countries to external shocks in the globalized (as opposed to a localized) world.

Medium induced mixing, spatial modulations, and critical modes in QCD

The mixing between the chiral condensate and the density in hot and dense quantum chromodynamics (QCD) matter is familiar. We show that the mixing relevant for the ground state is considerably more extensive, and in particular also involves gluonic degrees of freedom. As a result, the Hessian of the QCD effective action is non-Hermitian, but retains a symmetry under combined charge and complex conjugation. This can lead to complex-conjugate pairs of eigenvalues of this Hessian, signaling regimes with spatially modulated correlations. Furthermore, based on the analytic structure of the quark determinant at a chiral critical point, we demonstrate that the corresponding massless critical mode is composed of the chiral condensate, the density and the Polyakov loops. Due to an avoided crossing, the critical mode turns out to be disconnected from the chiral condensate in vacuum. We present general arguments for all these features and illustrate them through explicit model calculations. Published by the American Physical Society 2024

The argument from undecidable dissension

The five modes of suspension of judgment outlined by Sextus Empiricus (HP XV 164-188) coordinate a complex argumentative strategy to prompt the general suspension of judgment. But modes (τρόπος) are general argument forms that can be deployed individually against the dogmatist, who is willing to accept that a certain answer to a question establishes how things really are. In this case, the aim of the modes is not the general suspension of judgment but the continuation of the investigation. I present a deductive version of the mode of undecidable dissension that pinpoints some principles and assumptions the skeptics requires to run their arguments.

New oscillation criteria for first-order differential equations with general delay argument

New oscillation criteria for first-order differential equations with general delay argument

On Drill Team and the musicality of videographic criticism

An article comprising the videographic study Drill Team alongside a written framing of its film studies origins and comparative methodology. The video attempts a performative audiovisual adaptation of a chapter section from Danijela Kulezic-Wilson’s 2020 book Sound Design is the New Score: Theory, Aesthetics, and Erotics of the Integrated Soundtrack. Drill Team explores both Kulezic-Wilson’s specific (if uncertain) argument about the relationship between two films, Beau Travail (Claire Denis, 1999) and The Fits (Anna Rose Holmer, 2015), and her general argument in the chapter about the “composed” nature of the sound (and music) design in these and other modern or contemporary films, as well as about the capacity of these films, and film generally, to use modes of embodied experience as the substance of their language.

The Case for Universal Long-Term Care

Long-term care (LTC) is one of the most pressing public policy challenges today. Implementing policies to meet the population's demands becomes relevant in many countries, particularly in a context of rapid population aging. Both the technical complexities and the financial burden of implementing LTC policies discourage policy makers’ actions in this area. In this environment, targeted policies arise as a solution to reduce the cost of implementing LTC policies. This article presents several arguments in favor of implementing universal—vs targeted—LTC initiatives. Arguments are divided into general arguments against targeting public policies, using categories proposed by Amartya Sen, and LTC-specific arguments, based on the concept of LTC as social security. Information shows that despite the financial arguments in favor of targeted policies, in the case of LTC, its costs may overcome the benefits. These results provide important lessons for policy makers, particularly regarding the design of (universal) LTC policies, warning that the allegedly simple solution of targeting benefits needs to be revisited, and replaced for policies that could balance universalism and resource constraints. This message is particularly important today for countries that face the challenge of increasing LTC needs and tighter resource constraints.

No free lunch for avoiding clustering vulnerabilities in distributed systems

Emergent design failures are ubiquitous in complex systems, and often arise when system elements cluster. Approaches to systematically reduce clustering could improve a design’s resilience, but reducing clustering is difficult if it is driven by collective interactions among design elements. Here, we use techniques from statistical physics to identify mechanisms by which spatial clusters of design elements emerge in complex systems modelled by heterogeneous networks. We find that, in addition to naive, attraction-driven clustering, heterogeneous networks can exhibit emergent, repulsion-driven clustering. We draw quantitative connections between our results on a model system in naval engineering to entropy-driven phenomena in nanoscale self-assembly, and give a general argument that the clustering phenomena we observe should arise in many distributed systems. We identify circumstances under which generic design problems will exhibit trade-offs between clustering and uncertainty in design objectives, and we present a framework to identify and quantify trade-offs to manage clustering vulnerabilities.

The minimal weak gravity conjecture

We examine the minimal constraints imposed by the Weak Gravity Conjecture (WGC) on the particle spectrum of a quantum gravity theory. Towers of super-extremal states have previously been argued to be required for consistency of the WGC under circle reduction. At the same time, there exist classes of theories where no tower of super-extremal particle states below the black hole threshold has been established with current techniques. We resolve this tension by arguing for the existence of a minimal radius for circle reductions of generic quantum gravity theories. Below this threshold, the notion of a circle compactification breaks down, bypassing the need for a tower of super-extremal states to satisfy the WGC after circle reduction. Based on this we propose that if a theory satisfies the WGC at the particle level below the black hole threshold, these states are sufficient for consistency under dimensional reduction, even in absence of a tower of super-extremal particles. Apart from general arguments, we provide independent evidence for this main result in F-, M- and string theory compactifications. According to the Emergent String Conjecture the only exception to the appearance of a minimal radius arises in asymptotically weak-coupling limits for heterotic strings, which aligns with the appearance of a weakly coupled super-extremal tower of particle states. This observation motivates a Minimal Weak Gravity Conjecture which states that towers of super-extremal particles occur if and only if they are required by consistency of the WGC under dimensional reduction.

Design of randomized clinical trials with a binary endpoint: Conditional versus unconditional analyses of a two-by-two table.

When designing a randomized clinical trial to compare two treatments, the sample size required to have desired power with a specified type 1 error depends on the hypothesis testing procedure. With a binary endpoint (e.g., response), the trial results can be displayed in a 2 × 2 table. If one does the analysis conditional on the number of positive responses, then using Fisher's exact test has an actual type 1 error less than or equal to the specified nominal type 1 error. Alternatively, one can use one of many unconditional "exact" tests that also preserve the type 1 error and are less conservative than Fisher's exact test. In particular, the unconditional test of Boschloo is always at least as powerful as Fisher's exact test, leading to smaller required sample sizes for clinical trials. However, many statisticians have argued over the years that the conditional analysis with Fisher's exact test is the only appropriate procedure. Since having smaller clinical trials is an extremely important consideration, we review the general arguments given for the conditional analysis of a 2 × 2 table in the context of a randomized clinical trial. We find the arguments not relevant in this context, or, if relevant, not completely convincing, suggesting the sample-size advantage of the unconditional tests should lead to their recommended use. We also briefly suggest that since designers of clinical trials practically always have target null and alternative response rates, there is the possibility of using this information to improve the power of the unconditional tests.

Dark dimension, the swampland, and the dark matter fraction composed of primordial near-extremal black holes

In a recent publication we studied the decay rate of primordial black holes perceiving the dark dimension, an innovative five-dimensional (5D) scenario that has a compact space with characteristic length scale in the micron range. We demonstrated that the rate of Hawking radiation of 5D black holes slows down compared to 4D black holes of the same mass. Armed with our findings we showed that for a species scale of O(1010 GeV), an all-dark-matter interpretation in terms of primordial black holes should be feasible for black hole masses in the range 1014≲M/g≲1021. As a natural outgrowth of our recent study, herein we calculate the Hawking evaporation of near-extremal 5D black holes. Using generic entropy arguments we demonstrate that Hawking evaporation of higher-dimensional near-extremal black holes proceeds at a slower rate than the corresponding Schwarzschild black holes of the same mass. Assisted by this result we show that if there were 5D primordial near-extremal black holes in nature, then a primordial black hole all-dark-matter interpretation would be possible in the mass range 105β≲M/g≲1021, where β is a parameter that controls the difference between mass and charge of the associated near-extremal black hole. Published by the American Physical Society 2024

Nonperturbative thermodynamic extrinsic curvature of the anyon gas

Thermodynamic extrinsic curvature is a new mathematical tool in thermodynamic geometry. By using the thermodynamic extrinsic curvature, one may obtain a more complete geometric representation of the critical phenomena and thermodynamics. We introduce nonperturbative thermodynamic extrinsic curvature of an ideal two-dimensional gas of anyons. Using extrinsic curvature, we find new fixed points in nonperturbative thermodynamics of the anyon gas that particles behave as semions. Here, we investigate the critical behavior of thermodynamic extrinsic curvature of two-dimensional Kagome Ising model near the critical point [Formula: see text] in a constant magnetic field and show that it behaves as [Formula: see text] with [Formula: see text], where [Formula: see text] denotes the critical exponent of the specific heat. Then, we consider the three-dimensional spherical model and show that the scaling behavior is [Formula: see text], where [Formula: see text]. Finally, using a general argument, we show that extrinsic curvature [Formula: see text] has two different scaling behaviors for positive and negative [Formula: see text]. For [Formula: see text], our results indicate that [Formula: see text]. However, for [Formula: see text], we found a different scaling behavior, where [Formula: see text].

Field redefinitions and infinite field anomalous dimensions

Field redefinitions are commonly used to reduce the number of operators in the Lagrangian by removing redundant operators and transforming to a minimal operator basis. We give a general argument that such field redefinitions, while leaving the S-matrix invariant and consequently finite, lead not only to infinite Green’s functions, but also to infinite field anomalous dimensions γϕ. These divergences cannot be removed by counterterms without reintroducing redundant operators.

Page-curve-like entanglement dynamics in open quantum systems

The entanglement entropy of a black hole and that of its Hawking radiation are expected to follow the so-called Page curve: After an increase in line with Hawking’s calculation, it is expected to decrease back to zero once the black hole has fully evaporated, as demanded by unitarity. Recently, a simple system-plus-bath model has been proposed which shows a similar behavior. Here, we make a general argument as to why such a Page-curve-like entanglement dynamics should be expected to hold generally for system-plus-bath models at small coupling and low temperatures, when the system is initialized in a pure state far from equilibrium. The interaction with the bath will then generate entanglement entropy, but it eventually has to decrease to the value prescribed by the corresponding mean-force Gibbs state. Under those conditions, it is close to the system ground state. We illustrate this on two paradigmatic open-quantum-system models, the exactly solvable harmonic quantum Brownian motion and the spin-boson model, which we study numerically. In the first example we find that the intermediate entropy of an initially localized impurity is higher for more localized initial states. In the second example, for an impurity initialized in the excited state, the Page time—when the entropy reaches its maximum—occurs when the excitation has half decayed. Published by the American Physical Society 2024