24 research outputs found
Scalar induced gravitational waves in modified teleparallel gravity theories
Primordial black holes (PBHs) forming out of the collapse of enhanced
cosmological perturbations provide access to the early Universe through their
associated observational signatures. In particular, enhanced cosmological
perturbations collapsing to form PBHs are responsible for the generation of a
stochastic gravitational-wave background (SGWB) induced by second-order
gravitational interactions, usually called scalar induced gravitational waves
(SIGWs). This SGWB is sensitive to the underlying gravitational theory; hence
it can be used as a novel tool to test the standard paradigm of gravity and
constrain possible deviations from general relativity. In this work, we study
the aforementioned GW signal within modified teleparallel gravity theories,
developing a formalism for the derivation of the GW spectral abundance within
any form of gravitational action. At the end, working within viable
models without matter-gravity couplings, and accounting for the effect of
mono-parametric gravity at the level of the source and the propagation
of the tensor perturbations, we show that the respective GW signal is
indistinguishable from that within GR. Interestingly, we find that in order to
break the degeneracy between different theories through the portal of
SIGWs one should necessarily consider non-minimal matter-gravity couplings at
the level of the gravitational action.Comment: 16 pages without appendices (24 in total), 2 figure
The Global/Local Product Attribute: Decomposition, Trivialization and Price Tradeoffs in Emerging and Developed Markets
Accelerating anti-globalization challenges previously undisputed assumptions about the importance of a product’s globalness/localness in purchase decisions. Putting these assumptions to test, we conceptualize globalness/localness as a distinct product attribute and decompose its utility into weight and preference components. Subsequently, we offer an equity-theory-based prediction of the attribute’s declining relevance and quantify its tradeoffs with other attributes by calculating global/local price premiums. Conjoint experiments in two countries (Austria-India) reveal that (1) emerging (developed) market consumers exhibit relative preference for global (local) products, (2) emerging market consumers perceive higher preference inequity between global and local products than developed market consumers, and (3) the corresponding inequity triggers consumers’ cognitive inequity regulation (manifested through attribute trivialization in developed markets) and behavioral inequity regulation (manifested through asymmetrical willingness to pay for global/local products across developed/emerging markets). We also find that attribute trivialization and price premium tolerance are moderated by consumers’ spatial identities and price segment. The findings contribute to the theoretical debate on the relevance of product globalness/localness in de-globalizing times and inform competitive strategy, segmentation-targeting-positioning, and international pricing decisions
Signatures of Superstring theory in NANOGrav
In this Letter, we extract for the first time signatures of Superstring
theory in the recently released NANOGrav data. We concentrate on the primordial
gravitational wave (GW) spectrum induced by the gravitational potential of a
population of primordial black holes (PBHs) generated in the framework of
no-scale Supergravity. In particular, working within Wess-Zumino type no-scale
Supergravity we find naturally-realised inflection-point inflationary
potentials, which can give rise to the formation of microscopic PBHs triggering
an early matter-dominated era (eMD) and evaporating before Big Bang
Nucleosythesis (BBN). Remarkably, we obtain an abundant production of
gravitational waves, whose profile is quite distinctive, characterized by a
strong oscillatory pattern and being in strong agreement with NANOGrav data.
Hence, such a signal can act as a potential signature of no-scale Supergravity
and Superstring theory at the current and near-future GW observations.Comment: Minor changes: new references and small discussion adde
How Downplaying Product Greenness Affects Performance Evaluations: Examining the Effects of Implicit and Explicit Green Signals in Advertising
Despite frequent reports that they favor products with environmental benefits, consumers often purchase conventional alternatives. One reason for this is the performance liability associated with green products, in which consumers perceive them as being less effective. This research examines the concept of “green understatement” (i.e., communication of implicit green signals) compared with “green emphasis” (i.e., communication of explicit green signals) in green product advertising as a strategy to enhance performance evaluations. We test whether, why, and when an implicit (versus explicit) advertising strategy leads to higher performance evaluation for green products. We suggest and show that implicit green signals are more effective in conditions under which consumers have more concerns about the product’s performance or have lower expectations about its greenness. More specifically, the results of two experimental studies show that implicit (versus explicit) communication about greenness leads to higher performance evaluations for products that are less commonly green (Study 1) and for products that have an optional green mode (Study 2). The findings aid in the understanding of how a green product advertising strategy may influence performance evaluations and provide managerial implications for green product promotion
Perturbative instabilities in Horava gravity
We investigate the scalar and tensor perturbations in Horava gravity, with
and without detailed balance, around a flat background. Once both types of
perturbations are taken into account, it is revealed that the theory is plagued
by ghost-like scalar instabilities in the range of parameters which would
render it power-counting renormalizable, that cannot be overcome by simple
tricks such as analytic continuation. Implementing a consistent flow between
the UV and IR limits seems thus more challenging than initially presumed,
regardless of whether the theory approaches General Relativity at low energies
or not. Even in the phenomenologically viable parameter space, the tensor
sector leads to additional potential problems, such as fine-tunings and
super-luminal propagation.Comment: 21 pages, version published at Class. Quant. Gra
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How Historical and Social Aspirations Reshape the Relationship between Corporate Financial Performance and Corporate Social Responsibility?
Integrating the behavioral theory of the firm into the discussion on why firms behave in socially responsible ways, the study here develops and empirically tests hypotheses articulating when and how past corporate financial performance (CFP) might lead to more or less engagement in corporate social responsibility (CSR). Rather than treating historical and social aspirations as comparable performance benchmarks that yield similar behavioral responses, as most prior studies do, these two modes of performance comparison may induce signals that executives interpret differently, and therefore may lead to conflicting firm responses towards CSR initiatives. Using panel data pertaining to a large sample of U.S. firms, the study finds that historical and social performance comparisons have differential effects on CSR engagement. The findings describe how different interpretations of achievement influence firm’s engagement in secondary activities concerning environmental and social issues—a topic that has received very little attention in prior empirical research
A Step-by-Step Guide of (Fuzzy Set) Qualitative Comparative Analysis: From Theory to Practice via an Implementation in a B2B Context
One of the challenges researchers face in using an analytic method is to fully understand its underlying logic and find ways to successfully incorporate it into the research process. Qualitative Comparative Analysis (QCA) is an example in case, where such a challenge has been partly addressed so far, despite the increasing popularity of the method. Although QCA user guides are widely available, researchers may face difficulties in implementing the method to address real-world, complex social phenomena. To address this issue, the present methodological paper provides a step-by-step guide of QCA and links the background theory of the method to its practical implementation, via an example in the business-to business (B2B) context of open and closed innovation. The paper provides practitioners and researchers alike with a clear roadmap on how to exploit the full potential of the method in order to derive insightful explanations in applied data analysis