Fully viable DHOST bounce with extra scalar

Abstract In this paper we construct a class of Degenerate Higher-Order Scalar-Tensor (DHOST) theories with an extra scalar field, which admits viable solutions of bouncing universe satisfying the following requirements: (i) absence of Belinski-Khalatnikov-Lifshitz (BKL) instability, ghost and gradient instability, (ii) absence of superluminality, (

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Spatial-Temporal Differences in the Effect of Epidemic Risk Perception on Potential Travel Intention: A Macropsychology-Based Risk Perception Perspective

Most of the previous studies on the impact of risk perception on travel intention are based on an individual psychological perspective, and the understanding based on the perspective of macropsychology is insufficient.Analyzing the temporal and spatial characteristics of risk perception theory at the macropsychological and regional levels will expa

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