On form factors and correlation functions in twistor space

Finite Temperature Correlation Functions From Form Factors

Loops in Twistor Space

We elucidate the one-loop twistor-space structure corresponding to momentum-space MHV diagrams. We also discuss the infrared divergences, and argue that only a limited set of MHV diagrams contain them. We show how to introduce a twistor-space regulator corresponding to dimensional regularization for the infrared-divergent diagrams. We also evaluate explicitly the ‘holomorphic anomaly’ pointed o...

Perturbative Gravity and Twistor Space

Tree amplitudes in gravity theories can be computed from those of gauge theory using the KLT relations [1]. Inspired by this observation, investigations [2,3,4,5] have been carried out in the hope of discovering a deeper connection at the perturbative level between N = 8 supergravity [6] and N = 4 super Yang-Mills. A link between these theories, beyond structural similarities like the non-abeli...

proficiency level and factors fostering reticence in efl learners

according to cheng (1999), in recent esl/efl literature, asian (especially east asian) learners of english as a foreign/second language have been arguably reported as reticent and passive learners. the most common allegations are that these students are reluctant to participate in classroom discourse; they are unwilling to give responses; they do not ask questions; and they are passive and over...

Compatible complex structures on twistor space

— Let M be a Riemannian 4-manifold. The associated twistor space is a bundle whose total space Z admits a natural metric. The aim of this article is to study properties of complex structures on Z which are compatible with the fibration and the metric. The results obtained enable us to translate some metric properties on M (scalar flat, scalar-flat Kähler...) in terms of complex properties of it...