We construct models of static spherical distributions of perfect fluid in trace-free Einstein gravity theory. The equations governing the gravitational field are equivalent to the standard Einstein's equations however, their presentation is manifestly different which motivates the question whether new information would emerge due to the nonlinearity of the field equations. The incompressible fluid assumption does not lead to the well known Schwarzschild interior metric of Einstein gravity and a term denoting the presence of a cosmological constant is present on account of the integration process. The Schwarzschild interior is regained as a special case of a richer geometry. On the other hand, when the Schwarzschild geometry is prescribed, a constant density fluid emerges consistent

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This study sought to understand the factors that influence the behavioural intention of households towards microgeneration technologies. This includes subjective knowledge (SK) within the TPB framework as a determinant of behavioural intention.Methods: A quantitative research approach was followed. A sample frame consisted of households as a unit. A structured questionnaire was administered by using convenience sampling approach. Respondents include members of households who were above the age of 18. Altogether, 237 usable self-administered questionnaires were used for the data.Results: A two-stage procedure to perform Structural Equation Modeling (SEM) analysis by using SPSS AMOS 25 was conducted. The results showed that subjective norms (SNs) and attitude (ATT) had a significant and positive relationship with behavioural intention. Subjective knowledge showed no significant relationship. Practical implications:Recommendations are made to marketers in relationship to cohesive message relating to microgeneration technologies with a special emphasis on reference groups in the messaging. For policymakers, there will be a need to consider the role of society and the immediate communities of potential adopters in their policy documents.Originality/value: This study contributes to the scarce understanding of microgeneration technology in emerging markets by testing a proposed model by using data. It also enriches the adoption models via empirically exploring the relationship between SK and behavioural intention.

It is known that the standard Schwarzschild interior metric is conformally flat and generates a constant density sphere in any spacetime dimension in Einstein and Einstein–Gauss–Bonnet (EGB) gravity. This motivates the questions: in EGB does the conformal flatness criterion yield the Schwarzschild metric? Does the assumption of constant density generate the Schwarzschild interior spacetime? The answer to both questions turn out in the negative in general. In the case of the constant density sphere, a generalised Schwarzschild metric emerges. When we invoke the conformal flatness condition the Schwarschild interior solution is obtained as one solution and another metric which does not yield a constant density hypersphere in EGB theory is found. For the latter solution one of the gravitational metrics is obtained explicitly while the other is determined up to quadratures in 5 and 6 dimensions. The physical properties of these new solutions are studied with the use of numerical methods and a parameter space is located for which both models display pleasing physical behaviour.

The planet is under threat. Unless all stakeholders, that is governments, businesses, and consumers, become more environmentally friendly, some predict dire consequences for the earth and all those who inhabit it. While governments and businesses have a role to play, green consumer behavior is vital to the sustainability of the environment. Consumers have been shown to express increasing concern for the environment, but in many studies this concern has been found not to be matched by actions, a phenomenon labelled the green gap. This chapter describes a study that investigated the existence and extent of the green gap amongst a sample of South African adult consumers and sought to determine possible reasons for a lack of green behavior. Recommendations are made to marketers and policy makers to encourage consumer cooperation in environmental sustainability.