Here the path integral is over real metrics modulo coordinate transformations, G denotes a renormalized Newton constant and the · · · indicate higher derivative terms like R, etc. There may also be nonlocal terms related to the conformal anomaly [2]. The integral over μ produces the volume fixing delta function δ( ∫ dx √ g − V ). If this integral were done in the saddle point approximation, the...

Statistical analysis is a powerful tool for the interpretation of potential field data. Recent findings on scaling properties of the density and susceptibility distribution in the Earth’s crust have had a strong impact on statistical methods. I introduce the concept of scaling features of potential fields and show how scaling models can be used in the processing and interpretation of magnetic a...

We studied time-lapse gravity surveys applied to the monitoring of an artificial aquifer storage and recovery ASR system in Leyden, Colorado. An abandoned underground coal mine has been developed into a subsurface water reservoir. Water from surface sources is injected into the artificial aquifer during winter for retrieval and use in summer. As a key component in the geophysical monitoring of ...

In this article we develop a physical interpretation for the deformed (doubly) special relativity theories (DSRs), based on a modification of the theory of measurement in special relativity. We suggest that it is useful to regard the DSRs as reflecting the manner in which quantum gravity effects induce Planck-suppressed distortions in the measurement of the “true” energy and momentum. This inte...

This paper addresses the extent to which both Julian Barbour‘s Machian formulation of general relativity and his interpretation of canonical quantum gravity can be called timeless. We differentiate two types of timelessness in Barbour‘s (1994a, 1994b and 1999c). We argue that Barbour‘s metaphysical contention that ours is a timeless world is crucially lacking an account of the essential feature...

[1] Mass redistribution and deformation cause spatiotemporal gravity changes in active volcano areas. The ability of the gravity measurements to detect subsurface magma movement as a precursor to volcanic eruptions is greatly enhanced if gravity changes are analyzed and modeled jointly with ground deformation data. One effective tool for this analysis is provided by the gravity and elevation ch...

We discuss the derivation of the so-called semi-classical equations for both mini-superspace and dilaton gravity. We find that there is no systematic derivation of a semi-classical theory in which quantum mechanics is formulated in a space-time that is a solution of Einstein's equation, with the expectation value of the matter stress tensor on the right-hand side. The issues involved are relate...