Matter-antimatter asymmetry and non-inertial effects

We investigate non-inertial effects on CP-violating processes using a model, based on the framework of quantum field theory in curved spacetimes, devised to account for the decay of accelerated particles. We show that the CP violation parameter for the decay of accelerated kaons into two pions decreases very slightly as very high accel erations are achieved, implying decreased asymmetry between matter and antimatter in this regime. We discuss the relationship between these results and cosmological processes surrounding matter-antimatter asymmetry and argue that, due to the connection between non-inertial and thermal phenomena established by the Unruh effect, this kind of computa tion may prove useful in furthering the understanding of thermodynamical effects in curved spacetimes

ATLANTIC EPIPHYTES: a data set of vascular and non-vascular epiphyte plants and lichens from the Atlantic Forest

Epiphytes are hyper-diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non-vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer-reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non-vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non-vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ

More than 10,000 pre-Columbian earthworks are still hidden throughout Amazonia

Indigenous societies are known to have occupied the Amazon basin for more than 12,000 years, but the scale of their influence on Amazonian forests remains uncertain. We report the discovery, using LIDAR (light detection and ranging) information from across the basin, of 24 previously undetected pre-Columbian earthworks beneath the forest canopy. Modeled distribution and abundance of large-scale archaeological sites across Amazonia suggest that between 10,272 and 23,648 sites remain to be discovered and that most will be found in the southwest. We also identified 53 domesticated tree species significantly associated with earthwork occurrence probability, likely suggesting past management practices. Closed-canopy forests across Amazonia are likely to contain thousands of undiscovered archaeological sites around which pre-Columbian societies actively modified forests, a discovery that opens opportunities for better understanding the magnitude of ancient human influence on Amazonia and its current state

A teoria clássica de Yang-Mills-Higgs : aspectos físicos e matemáticos

O presente trabalho tem como principal objetivo a realização de um estudo do caso clássico de teorias de gauge. Para tanto, são introduzidas as ferramentas matemáticas necessárias e os princípios físicos que fundamentam tais teorias. Adicionalmente, são realizadas a descrição do mecanismo de Higgs nesse contexto e a análise acerca da existência de soluções de vórtices e de suas propriedades, no caso bidimensional.The present work’s main aim is a study of classical gauge theories. For this purpose, an introduction to the mathematical tools and physcial principles that ground such theories is made. Aditionally, the description of the Higgs mechanism in this context and the analysis of the existence of vortex solutions and their properties, in the two dimensional case, are realized

A teoria clássica de Yang-Mills-Higgs : aspectos físicos e matemáticos

O presente trabalho tem como principal objetivo a realização de um estudo do caso clássico de teorias de gauge. Para tanto, são introduzidas as ferramentas matemáticas necessárias e os princípios físicos que fundamentam tais teorias. Adicionalmente, são realizadas a descrição do mecanismo de Higgs nesse contexto e a análise acerca da existência de soluções de vórtices e de suas propriedades, no caso bidimensional.The present work’s main aim is a study of classical gauge theories. For this purpose, an introduction to the mathematical tools and physcial principles that ground such theories is made. Aditionally, the description of the Higgs mechanism in this context and the analysis of the existence of vortex solutions and their properties, in the two dimensional case, are realized

Sobre violação CP e efeitos não-inerciais relativísticos

This dissertation investigates the impact that non-inertial effects predicted by quantum field theory in curved spacetimes have on the phenomenon of CP violation by analyzing the relative rate of CP-violating meson decays when the particles involved are accelerated. The results obtained agree with previous analyses, in that an increase in decay rates with increasing acceleration is predicted, and lead to the conclusion that the amplitude of CP violation in meson systems decreases very slightly with increasing acceleration. The problem of matter–antimatter asymmetry and its relationship with non-inertial effects and CP violation are briefly discussed.Esta dissertação investiga o impacto que efeitos não-inerciais previstos pela teoria quântica de campos em espaços-tempos curvos têm sobre o fenômeno da violação CP ao analisar a taxa relativa de decaimentos de mésons que violam a simetria CP quando as partículas envolvidas são aceleradas. Os resultados obtidos estão em acordo com análises anteriores, no sentido de que é previsto um aumento na taxa de decaimento com um aumento na aceleração, e levam à conclusão de que a amplitude de violação CP em sistemas de mésons diminui ligeiramente com um aumento na aceleração. O problema da assimetria matéria–antimatéria e a sua relação com efeitos não-inerciais e violação CP são brevemente discutidos