the normalized full gradient (nfg) method defined by berezkin (1967, 1973 and 1998) is used for downward continuation maps. analytical downward continuation is a method to estimate the field closer to the source and consequently results in a better resolution of underground rock distribution. however, the usefulness of this process is limited by the fact that the operation is extremely sensitiv...

Using the cosmological perturbation theory in terms of the δN formalism, we find the simple formulation of the evolution of the curvature perturbation in generalized gravity theories. Compared with the standard gravity theory, a crucial difference appears in the end-boundary of the inflationary stage, which is due to the non-ideal form of the energy momentum tensor that depends explicitly on th...

Evolution of primordial fluctuations in a Brans-Dicke type scalar-tensor gravity theory is comprehensively investigated. The harmonic attractor model, in which the scalar field has its harmonic effective potential in the Einstein conformal frame and the theory relaxes toward Einstein gravity with time, is considered. The evolution of adiabatic initial perturbations in flat SCDM models is examin...

Violation of parity symmetry in the gravitational sector, which manifests into unequal left and right circular polarization states primordial waves, represents a way to test high-energy modifications general relativity. In this paper we study inflation within recently proposed chiral scalar-tensor theories gravity, that extend Chern-Simons gravity by including parity-violating operators contain...

Scalar–tensor gravity is the simplest and best understood modification of general relativity, consisting of a real scalar field coupled directly to the Ricci scalar curvature. Models of this type have self-accelerating solutions. In an example inspired by string dilaton couplings, scalar–tensor gravity coupled to ordinary matter exhibits a de Sitter type expansion, even in the presence of a neg...

I prove that classical gravity coupled with quantized matter can be renormalized with a finite number of independent couplings, plus field redefinitions, without introducing higher-derivative kinetic terms in the gravitational sector, but adding vertices that couple the matter stress-tensor with the Ricci tensor. The theory is called “acausal gravity”, because it predicts the violation of causa...

We consider the inverse problem of estimating the parameters describing a seismic source, based on time-dependent ground motion recordings at a number of receiver stations. The source is modeled as a point moment tensor forcing, characterized by its location, moment tensor components, start time, and frequency parameter in the time function. In total, there are 11 unknown parameters. We use a n...

A discussion of the field content of quadratic higher-derivative gravitation is presented, together with a new example of a massless spin-two field consistently coupled to gravity. The full quadratic gravity theory is shown to be equivalent to a canonical secondorder theory of a massive scalar field, a massive spin-two symmetric tensor field and gravity. The conditions showing that the tensor f...

Tensor decompositions are higher-order analogues of matrix decompositions and have proven to be powerful tools for data analysis. In particular, we are interested in the canonical tensor decomposition, otherwise known as CANDECOMP/PARAFAC (CP), which expresses a tensor as the sum of component rank-one tensors and is used in a multitude of applications such as chemometrics, signal processing, ne...