Lancaster University

About: Lancaster University is a education organization based out in Lancaster, Lancashire, United Kingdom. It is known for research contribution in the topics: Population & Context (language use). The organization has 13080 authors who have published 44563 publications receiving 1692277 citations. The organization is also known as: The University of Lancaster & Lancaster University.

Observation of an Inverse Energy Cascade in Developed Acoustic Turbulence in Superfluid Helium

Abstract: We report observation of an inverse energy cascade in second sound acoustic turbulence in He II. Its onset occurs above a critical driving energy and it is accompanied by giant waves that constitute an acoustic analogue of the rogue waves that occasionally appear on the surface of the ocean. The theory of the phenomenon is developed and shown to be in good agreement with the experiments.

Early Pleistocene human occupation at the edge of the boreal zone in northwest Europe

Abstract: Early humans colonized Eurasia fairly swiftly after they left Africa more than 1.8 million years ago, occupying tropical and Mediterranean habitats from Flores in the east to present-day Spain in the west. The prevailing view from sparse fossil and archaeological evidence has been that humans were still largely adapted to warm climates, and penetrated more than 45° north only in exceptionally warm intervals. New findings of artefacts, fauna and flora from a river deposit in Norfolk, UK, dating back more than 780,000 years, will change that perception. Excavations at the eroding coastal site of Happisburgh uncovered 78 flint artefacts, including flint tools, from what was a forest habitat in a climate resembling that of southern Britain today. This suggests that humans were capable of living in northern Europe in cooler intervals much earlier than was thought. Hominins colonized Eurasia fairly swiftly after they left Africa around 1.75 million years ago, although it had been thought that they did not penetrate beyond 45° N except in very warm intervals. Now, however, artefacts, fauna and flora dating back more 0.78 million years have been found in a river deposit in Norfolk, England. The findings show that humans were capable of penetrating northern Europe in cooler intervals, and will prompt a re-evaluation of the adaptations and abilities of humans at this early date. The dispersal of early humans from Africa by 1.75 Myr ago led to a marked expansion of their range, from the island of Flores in the east to the Iberian peninsula in the west1,2,3,4,5. This range encompassed tropical forest, savannah and Mediterranean habitats, but has hitherto not been demonstrated beyond 45° N. Until recently, early colonization in Europe was thought to be confined to the area south of the Pyrenees and Alps. However, evidence from Pakefield (Suffolk, UK) at ∼0.7 Myr indicated that humans occupied northern European latitudes when a Mediterranean-type climate prevailed6. This provided the basis for an ‘ebb and flow’ model, where human populations were thought to survive in southern refugia during cold stages, only expanding northwards during fully temperate climates5. Here we present new evidence from Happisburgh (Norfolk, UK) demonstrating that Early Pleistocene hominins were present in northern Europe >0.78 Myr ago when they were able to survive at the southern edge of the boreal zone. This has significant implications for our understanding of early human behaviour, adaptation and survival, as well as the tempo and mode of colonization after their first dispersal out of Africa.

Black holes, gravitational waves and fundamental physics: a roadmap

Abstract: The grand challenges of contemporary fundamental physics-dark matter, dark energy, vacuum energy, inflation and early universe cosmology, singularities and the hierarchy problem-all involve gravity as a key component. And of all gravitational phenomena, black holes stand out in their elegant simplicity, while harbouring some of the most remarkable predictions of General Relativity: event horizons, singularities and ergoregions. The hitherto invisible landscape of the gravitational Universe is being unveiled before our eyes: the historical direct detection of gravitational waves by the LIGO-Virgo collaboration marks the dawn of a new era of scientific exploration. Gravitational-wave astronomy will allow us to test models of black hole formation, growth and evolution, as well as models of gravitational-wave generation and propagation. It will provide evidence for event horizons and ergoregions, test the theory of General Relativity itself, and may reveal the existence of new fundamental fields. The synthesis of these results has the potential to radically reshape our understanding of the cosmos and of the laws of Nature. The purpose of this work is to present a concise, yet comprehensive overview of the state of the art in the relevant fields of research, summarize important open problems, and lay out a roadmap for future progress. This write-up is an initiative taken within the framework of the European Action on 'Black holes, Gravitational waves and Fundamental Physics'. © 2019 IOP Publishing Ltd.

High-sensitivity photodetectors based on multilayer GaTe flakes

Abstract: Optoelectronic devices based on layered materials such as graphene have resulted in significant interest due to their unique properties and potential technological applications. The electric and optoelectronic properties of nano GaTe flakes as layered materials are described in this article. The transistor fabricated from multilayer GaTe shows a p-type action with a hole mobility of about 0.2 cm2 V–1 s–1. The gate transistor exhibits a high photoresponsivity of 104 A/W, which is greatly better than that of graphene, MoS2, and other layered compounds. Meanwhile, the response speed of 6 ms is also very fast. Both the high photoresponsivity and the fast response time described in the present study strongly suggest that multilayer GaTe is a promising candidate for future optoelectronic and photosensitive device applications.

Seeing Like a Survey

Abstract: This article explores a performative understanding of social science method. First, it draws on STS to consider the plausibility of the claim that research methods generate not only representations of reality, but also the realities those representations depict. Second, it undertakes an archaeology of a major survey — a Eurobarometer investigation of European citizens' attitudes to farm animal welfare — in order to explore the character of its performativity. Finally, it considers some of the implications of the performativity of research tools for the future of methods in social science.