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The presence of exotic matter for the existence of the wormhole geometry has been an unavoidable problem in GR. In recent studies, researchers have tried to deal with this issue using modified gravity theories where the WH geometry is explained by the extra curvature terms and NEC's are not violated signifying the standard matter in the WH geometry. In this paper, we investigate the solutions of traversable wormholes with normal matter in the throat within the framework of symmetric teleparallel gravity f (Q) , where Q is the non-metricity scalar that defines the gravitational interaction. We analyze the wormhole geometries for three forms of function f (Q). First is the linear form f (Q) = α Q , second a nonlinear form f (Q) = α Q 2 + β and third one a more general quadratic form f (Q) = α Q 2 + β Q + γ with α , β and γ being the constants. For all the three cases, the shape function is taken as b (r) = r 0 ln (r + 1) ln (r 0 + 1) where r 0 is the throat radius. A special variable redshift function is considered for the discussion. All the energy conditions are then examined for the existence and stability of the wormhole geometry. [ABSTRACT FROM AUTHOR]

Teleparallel theories of gravity are described in terms of the tetrad of a metric and a flat connection with torsion. In this paper, we study spherical symmetry in a modified teleparallel theory of gravity which is based on an arbitrary function of the five possible scalars constructed from the irreducible parts of torsion. This theory is a generalization of the so-called New General Relativity theory. We find that only two scalars are different to zero in spherical symmetry and we solve the corresponding field equations analytically for conformal Teleparallel gravity, and then perturbatively around Schwarzschild geometry for the general perturbative theory around GR. Finally, we compute phenomenological effects from the perturbed solutions such as the photon sphere, perihelion shift, Shapiro delay, and the light deflection. We find their correspondent correction to the standard GR contribution and their dependence on the three model parameters. [ABSTRACT FROM AUTHOR]