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Weoutline the program to apply modern quantum field theory methods to calculate observables in classical general relativity through a truncation to classical terms of the multigraviton, two-body, on-shell scattering amplitudes between massive fields. Since only long-distance interactions corresponding to nonanalytic pieces need to be included, unitarity cuts provide substantial simplifications for both post-Newtonian and post-Minkowskian expansions. We illustrate this quantum field theoretic approach to classical general relativity by computing the interaction potentials to second order in the post-Newtonian expansion, as well as the scattering functions for two massive objects to second order in the post-Minkowskian expansion. We also derive an all-order exact result for gravitational light-by-light scattering.
This article was published in the following journal.
Name: Physical review letters
We combine tools from effective field theory and generalized unitarity to construct a map between on-shell scattering amplitudes and the classical potential for interacting spinless particles. For gen...
We present a bottom-up construction of vector effective field theories using the infrared structure of scattering amplitudes. Our results employ two distinct probes of soft kinematics: multiple soft l...
Effective field theory methods suggest that some rather general extensions of general relativity include, or are mimicked by, certain higher-order curvature corrections, with coupling constants expect...
In general, to determine the sensitivity of light transport to tissue from morphological features of clinical significance. Determine how specific structural features contribute to light ...
The overall objective of this work is to identify changes in the optical properties of oral tissues to develop a non-invasive tool for the detection, diagnosis and screening of oral pathol...
This study will use a method called dynamic light scattering (DLS) to study the lens of the eye in young normal subjects. The DLS device uses a very dim laser light to study the lens of th...
The relation between burst and suppression periods in transcranial and direct cortical recorded EEG with cortical amplitudes median nerve somatosensory evoked potentials is studied. ...
The elfitor device is a small non invasive device that uses dynamic light scattering to measure skin bloodflow, blood velocity, coagulation and hemodynamic parameters. In this study, the i...
Scattering of a beam of electromagnetic or acoustic RADIATION, or particles, at small angles by particles or cavities whose dimensions are many times as large as the wavelength of the radiation or the de Broglie wavelength of the scattered particles. Also know as low angle scattering. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed) Small angle scattering (SAS) techniques, small angle neutron (SANS), X-ray (SAXS), and light (SALS, or just LS) scattering, are used to characterize objects on a nanoscale.
The interactions of particles responsible for their scattering and transformations (decays and reactions). Because of interactions, an isolated particle may decay into other particles. Two particles passing near each other may transform, perhaps into the same particles but with changed momenta (elastic scattering) or into other particles (inelastic scattering). Interactions fall into three groups: strong, electromagnetic, and weak. (From McGraw-Hill Encyclopedia of Science & Technology, 7th ed)
The use of light interaction (scattering, absorption, and fluorescence) with biological tissue to obtain morphologically based information. It includes measuring inherent tissue optical properties such as scattering, absorption, and autofluorescence; or optical properties of exogenous targeted fluorescent molecular probes such as those used in optical MOLECULAR IMAGING, or nontargeted optical CONTRAST AGENTS.
An analytical technique for measuring particle size of molecules that are less than a micron in diameter dispersed or dissolved in a liquid.
The scattering of NEUTRONS by matter, especially crystals, with accompanying variation in intensity due to interference effects. It is useful in CRYSTALLOGRAPHY and POWDER DIFFRACTION.