Naturalness

About: Naturalness is a research topic. Over the lifetime, 1305 publications have been published within this topic receiving 31737 citations.

Local Unit Invariance, Back-Reacting Tractors and the Cosmological Constant Problem

Abstract: When physics is expressed in a way that is independent of local choices of unit systems, Riemannian geometry is replaced by conformal geometry. Moreover masses become geometric, appearing as Weyl weights of tractors (conformal multiplets of fields necessary to keep local unit invariance manifest). The relationship between these weights and masses is through the scalar curvature. As a consequence mass terms are spacetime dependent for off-shell gravitational backgrounds, but happily constant for physical, Einstein manifolds. Unfortunately this introduces a naturalness problem because the scalar curvature is proportional to the cosmological constant. By writing down tractor stress tensors (multiplets built from the standard stress tensor and its first and second derivatives), we show how back-reaction solves this naturalness problem. We also show that classical back-reaction generates an interesting potential for scalar fields. We speculate that a proper description of how physical systems couple to scale, could improve our understanding of naturalness problems caused by the disparity between the particle physics and observed, cosmological constants. We further give some ideas how an ambient description of tractor calculus could lead to a Ricci-flat/CFT correspondence which generalizes the AdS side of Maldacena's duality to a Ricci-flat space of one higher dimension.

Naturalness Judgement of L2 Mandarin Chinese - Does timing matter?

Abstract: This study aims to investigate native speakers’ perception of prosodic variation of Chinese utterances. It is known that timing is crucial for intelligibility in English, Japanese and other accent languages [9, 13 ,14 ,16]. A tone language, Chinese relies heavily on the use of pitch more than do other languages for the purpose of distinguishing the meaning of the segmentally same words as well as expressing intonation. It is expected that pitch is the most important prosodic factor for the naturalness judgment of Chinese. However, no empirical data have been presented to support this view to date. In general, listeners are more sensitive to the deviation of timing than pitch. Pitch change also triggers slight change in duration. Whether the significance of timing for naturalness is universal across languages and applies to tone languages as well, relative importance of timing and pitch in Chinese was investigated using L2 Chinese speech. The results indicated that Chinese native listeners do notice the deviation of timing and regard it as accented speech. Index Terms: naturalness, pitch, timing, foreign accent, Chinese

Underwater Image Enhancement Using Laplace Decomposition

Abstract: This letter presents underwater image enhancement using Laplace decomposition. Underwater image undergoes Laplace decomposition resulting in low- and high-frequency bands. Haze is removed from the low-frequency band, and then it is normalized for white balancing. The high-frequency band is amplified for edge preservation. Adding the two frequency images results in an enhanced image. It has improved, in contrast, color, object prominence, edge preservation, reduced artifacts, and naturalness as compared to other methods related to underwater image enhancement.

Musings on the Current Status of HEP

Abstract: I give a brief review of theoretical high energy physics as we know it today in the general picture of quantum physics. Prospects for future developments are outlined.