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Manufacturing or repairing parts on-site, high geometric freedom, and feedstock efficiency have long been regarded as nascent capabilities of additive manufacturing (AM) technologies. Researchers aim to adopt these capabilities for the future of space exploration, and polymer AM demonstrations in space were achieved in 2014; however, methods to process metals and other materials are needed. This paper provides a comprehensive review of AM research tested on reduced-gravity platforms from academia and industry across the globe. In addition, complementary processes and technologies under development are summarized. Reports from the literature are categorized by established AM process terminology and processed material. Lastly, alternatives to enabling metal AM in space are discussed, and knowledge gaps are presented. [ABSTRACT FROM AUTHOR]

Kaniadakis statistics is a widespread paradigm to describe complex systems in the relativistic realm. Recently, gravitational and cosmological scenarios based on Kaniadakis (κ -deformed) entropy have been considered, leading to generalized models that predict a richer phenomenology comparing to their standard Maxwell–Boltzmann counterparts. The purpose of the present effort is to explore recent advances and future challenges of Gravity and Cosmology in Kaniadakis statistics. More specifically, the first part of the work contains a review of κ -entropy implications on Holographic Dark Energy, Entropic Gravity, Black hole thermodynamics and Loop Quantum Gravity, among others. In the second part, we focus on the study of Big Bang Nucleosynthesis in Kaniadakis Cosmology. By demanding consistency between theoretical predictions of our model and observational measurements of freeze-out temperature fluctuations and primordial abundances of 4 H e and D, we constrain the free κ -parameter, discussing to what extent the Kaniadakis framework can provide a successful description of the observed Universe. [ABSTRACT FROM AUTHOR]

Microwave hydrodiffusion and gravity (MHG) is a technology created not only to extract essential oils but also highly effective in obtaining fruit extracts/juices rich in phenolic compounds. Therefore, this study addresses existing research on MHG to extract phenolic compounds from fruits, highlighting their main findings and the knowledge gaps that can still be explored. The topics covered include describing the instrumentation, extraction mechanisms, and conditions used, in addition to the areas of application of this technique and matrices. Studies on the identification and quantification of phenolic compounds in fruit extracts obtained by MHG have been presented and discussed as well as assays used to verify the in vitro and in vivo antioxidant capacity of these extracts and analyses showing the economic viability of using MHG. Thus, this literature review aims to present a promising green method to obtain fruit extracts rich in phenolic compounds free of solvents, being a highly potential technique to be explored for bioactive compound extraction. [ABSTRACT FROM AUTHOR]

The article discusses the album "Since Time Is Gravity" by Natural Information Society Community Ensemble with Ari Brown. It explores the ethics of expression in music, including naming the group and the artwork used. The article highlights the shift from individual thinking to group thinking in the naming of the ensemble and emphasizes the importance of conversation and shared principles of exchange among the musicians. It also mentions the inclusion of Chicago jazz icon Ari Brown and describes the music on the album as a compelling mix of pulsating currents and dissonant melodies. The article concludes by discussing the album's artwork, which is described as a map that helps navigate the listener through the unique and powerful music created by the community of players. [Extracted from the article]

We provide a historical review and critique of regional geoid and quasigeoid modelling over the Australian continent, covering the earliest models from the late 1960s through to the present day and beyond. The most recently released official model for GPS/GNSS surveyors, AUSGeoid2020, was specifically calculated to enable them to determine Australian Height Datum heights from Geocentric Datum of Australia 2020 ellipsoidal heights in a more direct manner without the need for postsurveying adjustments. We summarise the deficiencies in the Australian Height Datum and how they are now being addressed by a proposed new vertical height system that is underpinned by a gravimetric-only quasigeoid model. We also summarise the results of some experiments that we have conducted to explore potential refinements that could be made to our computational processes, and future plans to acquire gravity data in the problematic coastal zones using airborne methods. [ABSTRACT FROM AUTHOR]

(Informational picture book. 7-9) [ABSTRACT FROM AUTHOR]

We review spherical and inhomogeneous analytic solutions of the field equations of Einstein and of scalar–tensor gravity, including Brans–Dicke theory, non-minimally (possibly conformally) coupled scalar fields, Horndeski, and beyond Horndeski/DHOST gravity. The zoo includes both static and dynamic solutions, asymptotically flat, and asymptotically Friedmann–Lemaître–Robertson–Walker ones. We minimize overlap with existing books and reviews and we place emphasis on scalar field spacetimes and on geometries that are "general" within certain classes. Relations between various solutions, which have largely emerged during the last decade, are pointed out. [ABSTRACT FROM AUTHOR]

However strong the connection between gravity, international crimes and universality appears when based only on universal crimes, diversifying the selection of international crimes may result in another outcome; a wider set of crimes may challenge the given meaning(s) of gravity as well as the depicted connection between gravity and universality. (Oxford University Press, Oxford, 2020), isbn: 9780198786153, 240 pp, £80.00. [Extracted from the article]

This review article presents the progress made over the last decade, since the introduction of effective field theories (EFTs) into post-Newtonian (PN) gravity. These have been put forward in the context of gravitational waves (GWs) from the compact binary inspiral. The mature development of this interdisciplinary field has resulted in significant advances of wide interest to physics at several levels serving various purposes. The field has firmly demonstrated, that seemingly disparate physical domains, such as quantum field theory and classical gravity, are related, and that the EFT framework is a universal one, where it has been proven to supply a robust methodology to boost progress in the development of PN theory. In this review emphasis was put on an accessible pedagogic presentation of the field theoretic aspects of the subject, with the view, that these are in fact common across the whole of theoretical physics, rather than in their original narrow quantum context. The review is aimed at a broad audience, from general readers new to the field, to specialists and experts in related subjects. The review begins with an overview of the introduction of EFTs into classical gravity and their development. Then, the basic ideas, which form the conceptual foundation of EFTs, are provided, and the strategy of a multi-stage EFT framework, which is utilized for the PN binary inspiral problem, is outlined. The main body of the review is then dedicated to presenting in detail the study of each of the effective theories at each of the intermediate scales in the problem, up to the actual GW observables. First, the EFT for a single compact object is considered, from which one proceeds to the EFT of a compact binary system, viewed as a composite particle with internal binding interactions. Finally, one arrives at the effective theory of the time-dependent multipole moments of the radiating system. The review is concluded with the multiple prospects of building on the progress in the field, and using further modern field theory insights and tools, to specifically address the study of GWs, as well as to broadly expand our fundamental understanding of gauge and gravity theories across the classical and quantum regimes. [ABSTRACT FROM AUTHOR]

The discovery of cosmic acceleration has triggered a consistent body of theoretical work aimed at modeling its phenomenology and understanding its fundamental physical nature. In recent years, a powerful formalism that accomplishes both these goals has been developed, the so-called effective field theory of dark energy. It can capture the behavior of a wide class of modified gravity theories and classify them according to the imprints they leave on the smooth background expansion history of the Universe and on the evolution of linear perturbations. The effective field theory of dark energy is based on a Lagrangian description of cosmological perturbations which depends on a number of functions of time, some of which are non-minimal couplings representing genuine deviations from General Relativity. Such a formalism is thus particularly convenient to fit and interpret the wealth of new data that will be provided by future galaxy surveys. Despite its recent appearance, this formalism has already allowed a systematic investigation of what lies beyond the General Relativity landscape and provided a conspicuous amount of theoretical predictions and observational results. In this review, we report on these achievements. [ABSTRACT FROM AUTHOR]

The book spends considerable time detailing Einstein's efforts from 1905 to 1915 when he worked out a general theory of relativity - the currently accepted theory of gravity - from which much of modern physics has developed. Schwarzschild found an exact solution to Einstein's field equations for the spacetime curvature outside of a nonrotating star - not a trivial task - and calculated that radius at which a black hole would form. When the Belgian priest and physicist Georges Lemaître told Einstein that the universe really is expanding, Einstein called his grasp of physics "abominable.". [Extracted from the article]

An acclaimed physicist takes a deep dive into one of the most fundamental and mysterious forces of the universe. [ABSTRACT FROM AUTHOR]

(Informational picture book. 5-8) [ABSTRACT FROM AUTHOR]

A review of the book "The Irresistible Attraction of Gravity: A Journey to Discover Black Holes," by Luciano Rezzolla, is presented.

Though it takes only a few brief pages, one of the most valuable of these methodological asides comes when Fara traces how Conduitt used his control over Newton's papers to carefully and deliberately shape Newton's posthumous public image. Patricia Fara is a historian of science at the University of Cambridge whose wide-ranging interests include eighteenth-century natural philosophy, the cultural history of science, and women in science. [Extracted from the article]

The author of the chapter explains the screening mechanisms behind modified gravity models, such as thin-shell screening, K-mouflage and Vainshtein mechanisms, the frame transformation or modified gravity models, such as f(R) gravity, Braneworld gravity or Horndeski theory. Modified gravity: progresses and outlook of theories, numerical techniques and observational tests: edited by Baojiu Li and Kazuya Koyama, Singapore, World Scientific, 2019, 313 pp., $98 (hardback), ISBN: 9789813273993. The book provides a detailed introduction and modern perspective on modified gravity scenarios, together with recent tests of gravity, approximation methods, astrophysical tests and laboratory constraints. [Extracted from the article]

The book is intended to be a graduate-level detailed overview of research material on specific frontier theoretical physics topics, focussing on the structure of gravity and gauge theory at very long distances. The first corner of the equivalence triangle is the soft theorems, that characterise the universal properties of Feynman diagrams and scattering amplitudes, when a massless external particle becomes soft or its energy is taken to zero. The author provides a concrete mathematical relation between the different subjects that characterise the universe at very long-distance scales, from soft theorems and memory effects, to asymptotic symmetries. [Extracted from the article]

Reviews the book "Gravity's Shadow: The Search for Gravitational Waves," by Harry Collins.

Reviews the book "Matters of Gravity: Special Effects and Supermen in the 20th Century," by Scott Bukatman.

Reviews the book "Gravity From the Ground Up," by B. Schutz.

Reviews the book `Einstein's Unfinished Symphony,' by Marcia Bartusiak.

Reviews the book `The Hunt for Zero Point,' by Nick Cook.

The article analyzes the poem "Paradise Lost" by John Milton. It focuses on Milton's descriptions of fall, drops, and ruins in the poem in addition to the Fall of Man and connect these thorough an exploration of gravity. In addition, the author examines how Milton uses a study of moral physics and certain paradoxes in the laws governing falling bodies as a poetic effect such as Satan's descent through chaos and Adam dropping a wreath for Eve.

The author proposes a compelling case for a nonlocal modification of Einstein's theory of gravity. This main assumption leads to an extension of Lorentz invariance for accelerated observers in Minkowski spacetime and a new classical nonlocal generalisation of Einstein's theory of gravitation, presented in this book. The book is concise and elegant, targeting physics readers looking for modified gravity answers in order to explain a number of cosmological problems, including the existence of dark matter. [Extracted from the article]

Leap-frogging The Elephant Riders and Jam Room, by the time of 2001's Pure Rock Fury the band had hit their frenetic stride, as ably demonstrated by Red Horse Rainbow and Smoke Banshee. Songs Of Much Gravity (1993 - 2001) Cherry Red/Hear No Evil QHNEbox152 (4CD) Early years box set from innovative groovesters This set charts the journey of Germantown, Maryland's finest from the generic-but-quite-interesting to wholly unique and totally mind-blowing. A final disc of bonus tracks and B-sides wraps up this rousing collection. [Extracted from the article]

The article reviews the book "The Art of Gravity," by Jay Rogoff.

The article reviews the book "Free Surface Flows Under Compensated Gravity Conditions," by Michael E. Dreyer.

(Informational picture book. 6-8) [ABSTRACT FROM AUTHOR]