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https://www.readbyqxmd.com/read/29429062/towards-precision-medicine-a-new-biomedical-cosmology
#1
M W Vegter
Precision Medicine has become a common label for data-intensive and patient-driven biomedical research. Its intended future is reflected in endeavours such as the Precision Medicine Initiative in the USA. This article addresses the question whether it is possible to discern a new 'medical cosmology' in Precision Medicine, a concept that was developed by Nicholas Jewson to describe comprehensive transformations involving various dimensions of biomedical knowledge and practice, such as vocabularies, the roles of patients and physicians and the conceptualisation of disease...
February 10, 2018: Medicine, Health Care, and Philosophy
https://www.readbyqxmd.com/read/29420285/a-whirling-plane-of-satellite-galaxies-around-centaurus-a-challenges-cold-dark-matter-cosmology
#2
Oliver Müller, Marcel S Pawlowski, Helmut Jerjen, Federico Lelli
The Milky Way and Andromeda galaxies are each surrounded by a thin plane of satellite dwarf galaxies that may be corotating. Cosmological simulations predict that most satellite galaxy systems are close to isotropic with random motions, so those two well-studied systems are often interpreted as rare statistical outliers. We test this assumption using the kinematics of satellite galaxies around the Centaurus A galaxy. Our statistical analysis reveals evidence for corotation in a narrow plane: Of the 16 Centaurus A satellites with kinematic data, 14 follow a coherent velocity pattern aligned with the long axis of their spatial distribution...
February 2, 2018: Science
https://www.readbyqxmd.com/read/29420279/galaxy-motions-cause-trouble-for-cosmology
#3
COMMENT
Michael Boylan-Kolchin
No abstract text is available yet for this article.
February 2, 2018: Science
https://www.readbyqxmd.com/read/29376704/thermal-dark-matter-below-a-mev
#4
Asher Berlin, Nikita Blinov
We consider a class of models in which thermal dark matter is lighter than a MeV. If dark matter thermalizes with the standard model below the temperature of neutrino-photon decoupling, equilibration and freeze-out cool and heat the standard model bath comparably, alleviating constraints from measurements of the effective number of neutrino species. We demonstrate this mechanism in a model consisting of fermionic dark matter coupled to a light scalar mediator. Thermal dark matter can be as light as a few keV, while remaining compatible with existing cosmological and astrophysical observations...
January 12, 2018: Physical Review Letters
https://www.readbyqxmd.com/read/29367833/forecast-and-analysis-of-the-cosmological-redshift-drift
#5
Ruth Lazkoz, Iker Leanizbarrutia, Vincenzo Salzano
The cosmological redshift drift could lead to the next step in high-precision cosmic geometric observations, becoming a direct and irrefutable test for cosmic acceleration. In order to test the viability and possible properties of this effect, also called Sandage-Loeb (SL) test, we generate a model-independent mock data set in order to compare its constraining power with that of the future mock data sets of Type Ia Supernovae (SNe) and Baryon Acoustic Oscillations (BAO). The performance of those data sets is analyzed by testing several cosmological models with the Markov chain Monte Carlo (MCMC) method, both independently as well as combining all data sets...
2018: European Physical Journal. C, Particles and Fields
https://www.readbyqxmd.com/read/29359429/matriarchy-buddhism-and-food-security-in-sanephong-thailand
#6
Solot Sirisai, Sinee Chotiboriboon, Charana Sapsuwan, Praiwan Tantivatanasathien, Nuchjaree Setapun, Prangtong Duangnosan, Nattapach Thongkam, Sasiwimon Chuangyanyong
Sanephong is a matriarchal Karen community located in western Thailand. The community benefits greatly from the availability of local foods, such as cereals, tubers, wild vegetables, mushrooms, fruits, and animals. In the first phase of this project, 387 distinct local foods were identified, which were shown to be good sources of energy, protein, and vitamins. Despite the availability of a variety of nutritious local foods, the majority of households surveyed expressed concern over a decline in local foods due to changing socio-economic and environmental conditions...
November 2017: Maternal & Child Nutrition
https://www.readbyqxmd.com/read/29358359/the-serendipity-of-electroweak-baryogenesis
#7
Géraldine Servant
The origin of the matter-antimatter asymmetry of the universe remains unexplained in the Standard Model (SM) of particle physics. The origin of the flavour structure is another major puzzle of the theory. In this article, we report on recent work attempting to link the two themes through the appealing framework of electroweak (EW) baryogenesis. We show that Yukawa couplings of SM fermions can be the source of CP violation for EW baryogenesis if they vary at the same time as the Higgs is acquiring its vacuum expectation value, offering new avenues for EW baryogenesis...
March 6, 2018: Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/29358358/accretion-of-a-symmetry-breaking-scalar-field-by-a-schwarzschild-black-hole
#8
Dina Traykova, Jonathan Braden, Hiranya V Peiris
We simulate the behaviour of a Higgs-like field in the vicinity of a Schwarzschild black hole using a highly accurate numerical framework. We consider both the limit of the zero-temperature Higgs potential and a toy model for the time-dependent evolution of the potential when immersed in a slowly cooling radiation bath. Through these numerical investigations, we aim to improve our understanding of the non-equilibrium dynamics of a symmetry-breaking field (such as the Higgs) in the vicinity of a compact object such as a black hole...
March 6, 2018: Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/29358357/renormalization-group-flow-of-the-higgs-potential
#9
REVIEW
Holger Gies, René Sondenheimer
We summarize results for local and global properties of the effective potential for the Higgs boson obtained from the functional renormalization group, which allows one to describe the effective potential as a function of both scalar field amplitude and renormalization group scale. This sheds light onto the limitations of standard estimates which rely on the identification of the two scales and helps in clarifying the origin of a possible property of meta-stability of the Higgs potential. We demonstrate that the inclusion of higher-dimensional operators induced by an underlying theory at a high scale (GUT or Planck scale) can relax the conventional lower bound on the Higgs mass derived from the criterion of absolute stability...
March 6, 2018: Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/29358356/signatures-of-higgs-dilaton-and-critical-higgs-inflation
#10
Juan García-Bellido
We test the Higgs dilaton inflation model (HDM) using the latest cosmological datasets, including the cosmic microwave background temperature, polarization and lensing data from the Planck satellite (2015), the BICEP and Keck Array experiments, the type Ia supernovae from the JLA catalogue, the baryon acoustic oscillations from CMASS, LOWZ and 6dF, the weak lensing data from the CFHTLenS survey and the matter power spectrum measurements from the latest SDSS data release. We find that the values of all cosmological parameters allowed by the HDM are well within the Planck satellite (2015) constraints...
March 6, 2018: Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/29358355/cosmological-implications-of-higgs-near-criticality
#11
REVIEW
J R Espinosa
The Standard Model electroweak (EW) vacuum, in the absence of new physics below the Planck scale, lies very close to the boundary between stability and metastability, with the last option being the most probable. Several cosmological implications of this so-called 'near-criticality' are discussed. In the metastable vacuum case, the main challenges that the survival of the EW vacuum faces during the evolution of the Universe are analysed. In the stable vacuum case, the possibility of implementing Higgs inflation is critically examined...
March 6, 2018: Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/29358354/is-electroweak-baryogenesis-dead
#12
REVIEW
James M Cline
Electroweak baryogenesis is severely challenged in its traditional settings: the minimal supersymmetric standard model, and in more general two Higgs doublet models. Fine tuning of parameters is required, or large couplings leading to a Landau pole at scales just above the new physics introduced. The situation is somewhat better in models with a singlet scalar coupling to the Higgs so as to give a strongly first-order phase transition due to a tree-level barrier, but even in this case no UV complete models had been demonstrated to give successful baryogenesis...
March 6, 2018: Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/29358353/vacuum-stability-in-the-early-universe-and-the-backreaction-of-classical-gravity
#13
REVIEW
Tommi Markkanen
In the case of a metastable electroweak vacuum, the quantum corrected effective potential plays a crucial role in the potential instability of the standard model. In the early universe, in particular during inflation and reheating, this instability can be triggered leading to catastrophic vacuum decay. We discuss how the large space-time curvature of the early universe can be incorporated in the calculation and in many cases significantly modify the flat space prediction. The two key new elements are the unavoidable generation of the non-minimal coupling between the Higgs field and the scalar curvature of gravity and a curvature induced contribution to the running of the constants...
March 6, 2018: Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/29358352/higgs-cosmology
#14
Arttu Rajantie
The discovery of the Higgs boson in 2012 and other results from the Large Hadron Collider have confirmed the standard model of particle physics as the correct theory of elementary particles and their interactions up to energies of several TeV. Remarkably, the theory may even remain valid all the way to the Planck scale of quantum gravity, and therefore it provides a solid theoretical basis for describing the early Universe. Furthermore, the Higgs field itself has unique properties that may have allowed it to play a central role in the evolution of the Universe, from inflation to cosmological phase transitions and the origin of both baryonic and dark matter, and possibly to determine its ultimate fate through the electroweak vacuum instability...
March 6, 2018: Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/29358351/gravitational-waves-from-a-first-order-electroweak-phase-transition-a-brief-review
#15
REVIEW
David J Weir
We review the production of gravitational waves by an electroweak first-order phase transition. The resulting signal is a good candidate for detection at next-generation gravitational wave detectors, such as LISA. Detection of such a source of gravitational waves could yield information about physics beyond the Standard Model that is complementary to that accessible to current and near-future collider experiments. We summarize efforts to simulate and model the phase transition and the resulting production of gravitational waves...
March 6, 2018: Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/29347597/general-purpose-graphics-processing-unit-implementation-of-cosmological-domain-wall-network-evolution
#16
J R C C C Correia, C J A P Martins
Topological defects unavoidably form at symmetry breaking phase transitions in the early universe. To probe the parameter space of theoretical models and set tighter experimental constraints (exploiting the recent advances in astrophysical observations), one requires more and more demanding simulations, and therefore more hardware resources and computation time. Improving the speed and efficiency of existing codes is essential. Here we present a general purpose graphics-processing-unit implementation of the canonical Press-Ryden-Spergel algorithm for the evolution of cosmological domain wall networks...
October 2017: Physical Review. E
https://www.readbyqxmd.com/read/29347028/continuous-time-random-walk-model-for-anomalous-diffusion-in-expanding-media
#17
F Le Vot, E Abad, S B Yuste
Expanding media are typical in many different fields, e.g., in biology and cosmology. In general, a medium expansion (contraction) brings about dramatic changes in the behavior of diffusive transport properties such as the set of positional moments and the Green's function. Here, we focus on the characterization of such effects when the diffusion process is described by the continuous-time random-walk (CTRW) model. As is well known, when the medium is static this model yields anomalous diffusion for a proper choice of the probability density function (pdf) for the jump length and the waiting time, but the behavior may change drastically if a medium expansion is superimposed on the intrinsic random motion of the diffusing particle...
September 2017: Physical Review. E
https://www.readbyqxmd.com/read/29335452/chaotic-universe-model
#18
Ekrem Aydiner
In this study, we consider nonlinear interactions between components such as dark energy, dark matter, matter and radiation in the framework of the Friedman-Robertson-Walker space-time and propose a simple interaction model based on the time evolution of the densities of these components. By using this model we show that these interactions can be given by Lotka-Volterra type equations. We numerically solve these coupling equations and show that interaction dynamics between dark energy-dark matter-matter or dark energy-dark matter-matter-radiation has a strange attractor for 0 > w de  >-1, w dm  ≥ 0, w m  ≥ 0 and w r  ≥ 0 values...
January 15, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29303345/implications-of-the-neutron-star-merger-gw170817-for-cosmological-scalar-tensor-theories
#19
Jeremy Sakstein, Bhuvnesh Jain
The LIGO and VIRGO Collaborations have recently announced the detection of gravitational waves from a neutron star-neutron star merger (GW170817) and the simultaneous measurement of an optical counterpart (the γ-ray burst GRB 170817A). The close arrival time of the gravitational and electromagnetic waves limits the difference in speed of photons and gravitons to be less than about 1 part in 10^{15}. This has three important implications for cosmological scalar-tensor gravity theories that are often touted as dark energy candidates and alternatives to the Λ cold dark matter model...
December 22, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/29303333/strong-constraints-on-cosmological-gravity-from-gw170817-and-grb-170817a
#20
T Baker, E Bellini, P G Ferreira, M Lagos, J Noller, I Sawicki
The detection of an electromagnetic counterpart (GRB 170817A) to the gravitational-wave signal (GW170817) from the merger of two neutron stars opens a completely new arena for testing theories of gravity. We show that this measurement allows us to place stringent constraints on general scalar-tensor and vector-tensor theories, while allowing us to place an independent bound on the graviton mass in bimetric theories of gravity. These constraints severely reduce the viable range of cosmological models that have been proposed as alternatives to general relativistic cosmology...
December 22, 2017: Physical Review Letters
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