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Problem definition: How can retailers incentivize customers to make healthier food choices? Price, convenience, and taste are known to be among the main drivers behind such choices. Unfortunately, healthier food options are often expensive and not adequately promoted. However, we are observing recent efforts to nudge customers toward healthier food. Methodology/results: In this paper, we conducted a field experiment with a global convenience store chain to better understand how different add-on bundle promotions influence healthy food choices. We considered three types of add-on bundles sequentially: (i) an unhealthy bundle (when customers purchased a coffee, they could add a pastry for $1), (ii) a healthy bundle (offering a healthy snack, such as fruit, vegetable, or protein, as a coffee add-on for $1), and (iii) a choice bundle (the option of either a pastry or a healthy snack as an add-on to coffee for $1). In addition to our field experiment, we conducted an online laboratory study to strengthen the validity of our results. Managerial implications: We found that offering healthy snacks as part of an add-on bundle significantly increased healthy purchases (and decreased unhealthy purchases). Surprisingly, this finding continued to hold for the choice bundle, that is, even when unhealthy snacks were concurrently on promotion. However, we did not observe a long-term stickiness effect, meaning that customers returned to their original (unhealthy) purchase patterns once the healthy or choice bundle was discontinued. Finally, we show that offering an add-on choice bundle is also beneficial for retailers, who can earn higher revenue and profit. Funding: This research was supported by the James McGill Scholar Award Fund, the Scale AI Chair Program, IIVADO (Institut de valorisation des données) Fundamental Research Project Grant, and two Discovery Grants from the Natural Sciences and Engineering Research Council of Canada. Supplemental Material: The online appendix is available at https://doi.org/10.1287/msom.2023.0336. [ABSTRACT FROM AUTHOR]

In this paper, we review the theoretical basis for generation of gravitational waves and the detection techniques used to detect a gravitational wave. To materialize this goal in a thorough way, we first start with a mathematical background for general relativity from which a clue for gravitational wave was conceived by Einstein. Thereafter, we give the classification scheme of gravitational waves such as (i) continuous gravitational waves, (ii) compact binary inspiral gravitational waves and (iii) stochastic gravitational wave. Necessary mathematical insight into gravitational waves from binaries is also dealt with which follows detection of gravitational waves based on the frequency classification. Ground-based observatories as well as space borne gravitational wave detectors are discussed in a length. We have provided an overview on the inflationary gravitational waves. In connection to data analysis by matched filtering there are a few highlights on the techniques, e.g. (i) random noise, (ii) power spectrum, (iii) shot noise and (iv) Gaussian noise. Optimal detection statistics for a gravitational wave detection is also in the pipeline of the discussion along with detailed necessity of the matched filter and deep learning. [ABSTRACT FROM AUTHOR]

In this paper, we present the historical background of the Thirty-Meter Telescope at Mount Mauna Kea and a few facts regarding scientific advancement. However, we will not focus on any politically motivated matters and ethical issues, rather our sincere concern is to highlight the overall history, philosophy, science and technology which have prevailed for any civilized advancement of the society. [ABSTRACT FROM AUTHOR]

In this work, we consider the vanishing complexity factor scenario which has opened up a whole new way of generating solutions to the Einstein field equations for the spherically symmetric structure of celestial bodies. By using this very rare condition on the system of two metric potentials, viz. gtt and grr , we make reduce it to a uni-metric potential system satisfying all physical conditions. Along with this, we further have considered that the space–time is deformed by dark matter (DM) content in DM haloes resulting into perturbations in the gtt and grr metric potentials. This DM deformation is mathematically done by the complete geometric decoupling method where the decoupling parameter β decides the amount of DM content. In connection to the claimed post-merger object in the GW170817 event we have argued that if these compact stars were in galactic DM haloes with the assumption that the radius remains the same, the compactness factor can grow within the range 1/3 to 4/9 and therefore can generate gravitational waves (GW) echoes. Additionally, we have presented effect of β on the generation of GW echoes in accordance with the observational constraints related to the compact stars GW190814, PSR J0740+6620, PSR J1614−2230, Cen X-3, and LMC X-4. [ABSTRACT FROM AUTHOR]

In order to unveil different features of gravitational waves due to massive objects like black hole etc., researchers primarily attempt to find the corresponding quasi normal modes from the relevant wave equations. In the present article, homotopy perturbation method (HPM) is employed to obtain the wave functions by solving wave equations for one‐dimensional potential barriers. Under this scheme (i) for constant potential barrier a generalized solution which reduces to the known solution as done by Chandrasekhar and Detweiler [Proc. R. Soc. Lond. A 344 (1975) 441] is produced, (ii) the wave equation for the Price potential [Phys. Rev. D 5 (1972) 2419; Phys. Rev. D 5 (1972) 2439] by HPM is solved. The wave functions (graphically) as well as quasi‐normal modes to those of the Press solution (1973) are compared. The present investigation is important in connection to further study related to the Zerilli potential and Regge‐Wheeler potential in case of black hole. [ABSTRACT FROM AUTHOR]

This work comprises a study of the thermodynamic behavior of modified f (R ̄ , T ̄) gravity, which had been developed based on a non-canonical theory known as K-essence theory. In this development, we use the Dirac–Born—Infeld (DBI) type of non-standard Lagrangian. We develop a modified first law and generalized second law of thermodynamics (GSLT) within the modified f (R ̄ , T ̄) gravity, where we consider the background metric to be the usual Friedmann–Lema i ˆ tre–Robertson–Walker (FLRW) type. A graphical analysis of surface gravity has been performed for the modified FLRW metric via the f (R ̄ , T ̄) theory, which is different from the usual FLRW gravity through the usual f (R , T) gravity. Exponential and power law scale factors are used to analyze cosmic surface gravity. Through the investigation of the modified GSLT, using the relation of scale factor with the scalar field, we have seen that during the initial phase of the universe, the entropy's rate of change may be either negative or positive, contingent upon the value of the curvature constant. The negativity of the entropy change indicates that the modified GSLT is not feasible in that particular area for a particular curvature constant. These traits suggest that during the inflationary period, entropy might have been either negative or positive. It has also been seen that entropy saturates every curvature value at different time ranges, which indicates the heat death of the universe. [ABSTRACT FROM AUTHOR]

In this paper, we examine the universe's expansion in f (R , L m) gravity for a particular form of f (R , L m) = R 2 + L m n. The field equations for flat FLRW metric with matter Lagrangian L m = ρ are derived. Hubble parameter in terms of red-shift(z) are derived using the linear form of Equation of State (EoS) parameter ω = w 0 + w 1 z. By using Bayesian statistical techniques based on χ 2 -minimization technique, we have obtained the best fit values of the model parameters of this model for cosmic chronometer and supernovae Pantheon datasets. The evolution of the equation of state parameter(ω), energy density (ρ), pressure (p), cosmographic parameters, and the impact of the energy conditions with best-fit values of the model parameters are all thoroughly examined. We have also analyze Om diagnostic's behaviour and determine the present age of universe for this model. • We examine the universe's expansion for a particular form of f(R,Lm). • We have obtained the best fit values of model parameters for CC and joint datasets. • Energy density, pressure, cosmographic parameters are thoroughly examined. • We have analysed Om diagnostic's behaviour and determine the age of universe. [ABSTRACT FROM AUTHOR]

The foundation of this paper is to present a comparative study of the properties of anisotropic solutions for compact stars in the framework of modified f (Q , T) gravity for the first time under the schemes of vanishing complexity, embedding class one, conformally flat and conformally Killing, where Q is the nonmetricity scalar and T is the trace of the energy-momentum tensor. The model f (Q , T) = ϕ Q + α Q n + 1 − γ (1 − e − Q / γ) + β T is chosen in order to compare the results of the various forms f (Q , T) and f (Q) gravity theories. The f (Q , T) and f (Q) gravities in this model are then further simplified to depend on parameters ϕ , α , γ & β. Then, we discussed several approaches to determining the spherically symmetric spacetime components. Schwarzschild geometry represents the exterior spacetime, while a Tolman-Kuchowiz spacetime is used to examine the spherically symmetric spacetime inside the interior geometry. Many properties of compact stars are investigated, like energy density, energy conditions, pressure profiles, sound speeds, gradients, adiabatic index, TOV equation, mass function, compactness, and redshift function are all carefully examined in order to complete the analysis. We have compiled results for both stable and unstable scenarios, derived from gravity theories categorized into various cases, with solutions considered under different frameworks such as Tolman-Kuchowiz spacetime, embedding class 1 spacetime, the vanishing complexity condition, the conformally flat condition, and the conformal Killing vector condition. [ABSTRACT FROM AUTHOR]