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New solutions of DHOST theories can be generated by applying a disformal tranformation to a known seed solution. We examine the nature of spherically symmetric solutions of DHOST gravity obtained by disforming static spherical scalar field solutions, or stealth solutions, of general relativity. It is shown that, in these cases, black hole horizons are never created by disforming a black hole seed. New DHOST solutions are then created by disforming two lesser known scalar field solutions of general relativity: Wymans ``other solution and the Husain-Martinez-Nu~nez one. These new solutions demonstrate that one can obtain black hole horizons, wormhole throats, or horizonless geometries by disforming non-stealth, time-dependent, seeds.
We have studied the shadow of a disformal Kerr black hole with an extra deformation parameter, which belongs to non-stealth rotating solutions in quadratic Degenerate Higher Order Scalar Tensor (DHOST) theory. Our result show that the size of the sha
We present a new class of nonsingular bounce cosmology free from instabilities, using a single scalar field coupled to gravity within the framework of the Degenerate Higher-Order Scalar-Tensor (DHOST) theories. In this type of scenarios, the gradient
We improve the DHOST Genesis proposed in cite{Ilyas:2020zcb}, such that the near scale invariant scalar power spectrum can be generated from the model itself, without involking extra mechanism like a string gas. Besides, the superluminality problem o
We study the frame dependence/independence of cosmological observables under disformal transformations, extending the previous results regarding conformal transformations, and provide the correspondence between Jordan-frame and Einstein-frame variabl
The deflection of light in the strong field limit is an important test for alternative theories of gravity. However, solutions for the metric that allow for analytic computations are not always available. We implement a hybrid analytic-numerical appr