@MastersThesis{Fornasa:2018:EsReBu,
author = "Fornasa, Pietra Rafaela",
title = "Estudo da rela{\c{c}}{\~a}o entre buracos negros primordiais e
as ondas gravitacionais detectadas pelo LIGO",
school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
year = "2018",
address = "S{\~a}o Jos{\'e} dos Campos",
month = "2018-03-02",
keywords = "buracos negros primordiais, LIGO, mat{\'e}ria escura, ondas
gravitacionais, buraco negro, primordial black holes, LIGO, dark
matter, gravitational waves, black hole.",
abstract = "A radia{\c{c}}{\~a}o gravitacional {\'e} prevista pela Teoria
da Relatividade Geral de Einstein como uma solu{\c{c}}{\~a}o
ondulat{\'o}ria para as Equa{\c{c}}{\~o}es de Campo. Somente em
2015 foi comprovada direta e observacionalmente a exist{\^e}ncia
dessas perturba{\c{c}}{\~o}es no espa{\c{c}}otempo,
atrav{\'e}s da detec{\c{c}}{\~a}o de ondas gravitacionais pelos
interfer{\^o}metros dos observat{\'o}rios LIGO (Laser
Interferometer Gravitational Waves Observatory). Essas ondas
gravitacionais foram geradas na coalesc{\^e}ncia de dois buracos
negros de alta massa e o evento foi nomeado GW150914. A massa
desses buracos negros intrigou a comunidade cient{\'{\i}}fica
uma vez que, da evolu{\c{c}}{\~a}o estelar, n{\~a}o se esperam
massas muito acima de 15 massas solares. Levantou-se ent{\~a}o a
seguinte quest{\~a}o: Qual a origem desses buracos negros?
Buscando responder essa quest{\~a}o foi desenvolvida uma
an{\'a}lise estat{\'{\i}}stica a partir da fun{\c{c}}{\~a}o
de distribui{\c{c}}{\~a}o da massa dos buracos negros detectados
pelo LIGO. Utilizando como priors uma distribui{\c{c}}{\~a}o
log-normal (modelo Aflleck-Dine) e uma lei de pot{\^e}ncia, foi
desenvolvido um m{\'e}todo para estudar qual {\'e} o modelo mais
favor{\'a}vel para explicar a origem desses buracos negros sendo
que a metodologia feita para esse estudo seguiu uma
estat{\'{\i}}stica Bayesiana. Ap{\'o}s o c{\'a}lculo da
m{\'a}xima verossimilhan{\c{c}}a o modelo Affleck-Dine se
mostrou levemente favor{\'a}vel indicando que esses dois modelos
(Aflleck-Dine e lei de pot{\^e}ncia) s{\~a}o consistentes e
poderiam explicar a origem desses eventos. {\'E} necess{\'a}rio
um maior n{\'u}mero de eventos para distinguir exatamente as duas
curvas e definir qual modelo descreve melhor e, caso o modelo
primordial prevale{\c{c}}a, analisar qual a
contribui{\c{c}}{\~a}o desses buracos negros para a mat{\'e}ria
escura do Universo. ABSTRACT: Gravitational radiation is predicted
by Einsteins Theory of General Relativity as a wave solution for
its Field Equation. But only in 2015 was verified directly and
observationally the existence of these perturbations in spacetime,
through the detection of gravitational waves by LIGO. The
gravitational waves were generated in the coalescence of two high
masses black holes and the event was named GW150914. Their
estimated masses have intrigued the scientific community since
they were not expected by stellar evolution which black holes have
masses higher than 15 solar masses. A new question has raised from
such detections: What is the origin of those black holes? Trying
to answer this question, a statistical analysis was developed to
from the mass distribution function of the black holes detected by
the LIGO. Using as priors a log-normal distribution (Aflleck-Dine
model) and a power law, a method was developed to study which
model is the most probable to explain the origin of such black
holes being that the methodology made for that study followed a
Bayesian statistic. After calculating the maximum likelihood, the
Affleck-Dine model was slightly favorable indicating that these
two models are consistent and could explain the origin of these
events. A greater number of events is required to distinguish
exactly the two curves and to define which model is the best to
describes and, if the primordial model prevails, to analyze the
contribution of those black holes to the dark matter of the
Universe.",
committee = "Ara{\'u}jo, Jos{\'e} Carlos Neves de (presidente) and Costa,
C{\'e}sar Augusto (presidente) and Souza, Carlos Alexandre
Wuensche de and Alves, M{\'a}rcio Eduardo da Silva",
englishtitle = "Study of the relationship between primordial black holes and the
gravitational waves detected by LIGO",
language = "pt",
pages = "95",
ibi = "8JMKD3MGP3W34R/3QN2DG2",
url = "http://urlib.net/ibi/8JMKD3MGP3W34R/3QN2DG2",
targetfile = "publicacao.pdf",
urlaccessdate = "18 abr. 2024"
}