Results 31 to 40 of about 3,588,956 (379)
Scalar-graviton amplitudes [PDF]
Journal of High Energy Physics, 2019 Abstract Using the CHY-formalism and its extension to a double cover we provide covariant expressions for tree-level amplitudes with two massive scalar legs and an arbitrary number of gravitons in D dimensions. Using unitarity methods, such amplitudes are needed inputs for the computation of post-Newtonian and post-Minkowskian ...
Bjerrum-Bohr, N. E. J. +3 more
openaire +7 more sources
STATISTIC OF SEASONAL AND DIURNAL VARIATIONS OF DOPPLER FREQUENCY SHIFT OF HF SIGNALS AT MID-LATITUDE RADIO PATH [PDF]
Radio Physics and Radio Astronomy, 2020 Purpose: An experimental study of signatures of traveling ionospheric disturbances (TID) observed in diurnal-seasonal variations of the parameters of probe HF signals propagating on theoblique single-hop RWM–LFO radio path, derived from the yearlong ...
A. I. Reznychenko +3 more
doaj +1 more source
Physics Reports, 2017 This a pedagogical introduction to scattering amplitudes in gauge theories. It proceeds from Dirac equation and Weyl fermions to the two pivot points of current developments: the recursion relations of Britto, Cachazo, Feng and Witten, and the unitarity cut method pioneered by Bern, Dixon, Dunbar and Kosower.
openaire +3 more sources
Positive amplitudes in the amplituhedron [PDF]
Journal of High Energy Physics, 2015 The all-loop integrand for scattering amplitudes in planar N = 4 SYM is determined by an "amplitude form" with logarithmic singularities on the boundary of the amplituhedron. In this note we provide strong evidence for a new striking property of the superamplitude, which we conjecture to be true to all loop orders: the amplitude form is positive when ...
Arkani-Hamed, Nima +2 more
openaire +6 more sources
International Journal of Adaptive Control and Signal Processing, EarlyView., 2023 Summary In this contribution, we propose a detailed study of interpolation‐based data‐driven methods that are of relevance in the model reduction and also in the systems and control communities. The data are given by samples of the transfer function of the underlying (unknown) model, that is, we analyze frequency‐response data.
Quirin Aumann, Ion Victor Gosea
wiley +1 more source
Electrically Tunable Metasurface with Independent Frequency and Amplitude Modulations
, 2020 Metasurfaces with actively tunable features are highly demanded for advanced applications in electronic and electromagnetic systems. However, realizing independent dual-tunability remains challenging and requires more efforts.
Jin Zhang +4 more
semanticscholar +1 more source
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2015 A brief review is given of why twistor geometry has taken a central place in the theory of scattering amplitudes for fundamental particles. The emphasis is on the twistor diagram formalism as originally proposed by Penrose, the development of which has now led to the definition by Arkani-Hamedet al.of the ‘amplituhedron’.
openaire +3 more sources
The Bs oscillation amplitude analysis [PDF]
, 1999 The properties of the amplitude method for $\Bs$ oscillation analyses are studied in detail. The world combination of measured amplitudes is converted into a likelihood profile as a function of oscillation frequency.
Abbaneo, D., Boix, G.
core +3 more sources
Complete amplitude and phase control of light using broadband holographic metasurfaces. [PDF]
Nanoscale, 2017 Reconstruction of light profiles with amplitude and phase information, called holography, is an attractive optical technology with various significant applications such as three-dimensional imaging and optical data storage.
Gun-Yeal Lee +8 more
semanticscholar +1 more source
Journal of High Energy Physics, 2023 Abstract We study scattering amplitudes in the shadow conformal primary basis, which satisfies the same defining properties as the original conformal primary basis and has many advantages over it. The shadow celestial amplitudes exhibit locality manifestly on the celestial sphere, and behave like correlation functions in conformal ...
Chi-Ming Chang +4 more
openaire +3 more sources