scholarly journals Is there evidence for a hotter Universe?

2020 ◽  
Vol 80 (10) ◽  
Author(s):  
Carlos A. P. Bengaly ◽  
Javier E. Gonzalez ◽  
Jailson S. Alcaniz
Keyword(s):  
Hubble Constant ◽  
Far Infrared ◽  
New Physics ◽  
Wilkinson Microwave Anisotropy Probe ◽  
Microwave Background ◽  
Independent Analysis ◽  
Independent Observations ◽  
Model Independent ◽  
Good Agreement ◽  
Made In

AbstractThe measurement of present-day temperature of the Cosmic Microwave Background (CMB), $$T_0 = 2.72548 \pm 0.00057$$ T 0 = 2.72548 ± 0.00057  K (1$$\sigma $$ σ ), made by the Far-InfraRed Absolute Spectrophotometer (FIRAS) as recalibrated by the Wilkinson Microwave Anisotropy Probe (WMAP), is one of the most precise measurements ever made in Cosmology. On the other hand, estimates of the Hubble Constant, $$H_0$$ H 0 , obtained from measurements of the CMB temperature fluctuations assuming the standard $$\varLambda $$ Λ CDM model exhibit a large ($$4.1\sigma $$ 4.1 σ ) tension when compared with low-redshift, model-independent observations. Recently, some authors argued that a slightly change in $$T_0$$ T 0 could alleviate or solve the $$H_0$$ H 0 -tension problem. Here, we investigate evidence for a hotter or colder universe by performing an independent analysis from currently available temperature-redshift T(z) measurements. Our analysis (parametric and non-parametric) shows a good agreement with the FIRAS measurement and a discrepancy of $$\ge 1.9\sigma $$ ≥ 1.9 σ from the $$T_0$$ T 0 values required to solve the $$H_0$$ H 0 tension. This result reinforces the idea that a solution of the $$H_0$$ H 0 -tension problem in fact requires either a better understanding of the systematic errors on the $$H_0$$ H 0 measurements or new physics.

scholarly journals Constraints on new physics in MFV models: A model-independent analysis of ΔF=1 processes

2009 ◽  
Vol 808 (1-2) ◽  
pp. 326-346 ◽  
Author(s):  
Tobias Hurth ◽  
Gino Isidori ◽  
Jernej F. Kamenik ◽  
Federico Mescia
Keyword(s):  
New Physics ◽  
Independent Analysis ◽  
Model Independent

Progress toward an accurate Hubble Constant

2017 ◽  
Vol 13 (S336) ◽  
pp. 80-85
Author(s):  
Sherry H. Suyu
Keyword(s):  
Gravitational Lensing ◽  
Critical Density ◽  
Hubble Constant ◽  
New Physics ◽  
Microwave Background ◽  
Current Standard ◽  
A Value ◽  
Constant Determination ◽  
Standard Cosmological Model ◽  
Water Masers

AbstractThe Hubble constant is a key cosmological parameter that sets the present-day expansion rate as well as the age, size, and critical density of the Universe. Intriguingly, there is currently a tension in the measurements of its value in the standard flat ΛCDM model – observations of the Cosmic Microwave Background with the Planck satellite lead to a value of the Hubble constant that is lower than the measurements from the local Cepheids-supernovae distance ladder and strong gravitational lensing. Precise and accurate Hubble constant measurements from independent probes, including water masers, are necessary to assess the significance of this tension and the possible need of new physics beyond the current standard cosmological model. We present the progress toward an accurate Hubble constant determination.

scholarly journals New physics in b → se+e−: A model independent analysis

2021 ◽  
pp. 115419
Author(s):  
Ashutosh Kumar Alok ◽  
Suman Kumbhakar ◽  
Jyoti Saini ◽  
S. Uma Sankar
Keyword(s):  
New Physics ◽  
Independent Analysis ◽  
Model Independent

scholarly journals Diphoton resonances at the LHC

2017 ◽  
Vol 32 (27) ◽  
pp. 1730024 ◽  
Author(s):  
Emiliano Molinaro ◽  
Natascia Vignaroli
Keyword(s):  
Effective Field Theory ◽  
New Physics ◽  
Effective Field ◽  
Current Status ◽  
Beyond The Standard Model ◽  
Theory Approach ◽  
Independent Analysis ◽  
The Standard Model ◽  
Model Independent ◽  
Production Mechanisms

We review the current status of searches for new physics beyond the Standard Model in the diphoton channel at the LHC and estimate the reach with future collected data. We perform a model independent analysis based on an effective field theory approach and different production mechanisms. As an illustrative example, we apply our results to a scenario of minimal composite dynamics.

scholarly journals Why reducing the cosmic sound horizon alone can not fully resolve the Hubble tension

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Karsten Jedamzik ◽  
Levon Pogosian ◽  
Gong-Bo Zhao
Keyword(s):  
Hubble Constant ◽  
New Physics ◽  
Acoustic Oscillations ◽  
Microwave Background ◽  
Neutrino Sector ◽  
The Standard Model ◽  
Primordial Magnetic Fields ◽  
The One ◽  
The Universe ◽  
Develop Tension

AbstractThe mismatch between the locally measured expansion rate of the universe and the one inferred from the cosmic microwave background measurements by Planck in the context of the standard ΛCDM, known as the Hubble tension, has become one of the most pressing problems in cosmology. A large number of amendments to the ΛCDM model have been proposed in order to solve this tension. Many of them introduce new physics, such as early dark energy, modifications of the standard model neutrino sector, extra radiation, primordial magnetic fields or varying fundamental constants, with the aim of reducing the sound horizon at recombination r⋆. We demonstrate here that any model which only reduces r⋆ can never fully resolve the Hubble tension while remaining consistent with other cosmological datasets. We show explicitly that models which achieve a higher Hubble constant with lower values of matter density Ωmh2 run into tension with the observations of baryon acoustic oscillations, while models with larger Ωmh2 develop tension with galaxy weak lensing data.

scholarly journals Model-Independent Test for Scale-Dependent Non-Gaussianities in the Cosmic Microwave Background

2009 ◽  
Vol 102 (13) ◽  
Author(s):  
C. Räth ◽  
G. E. Morfill ◽  
G. Rossmanith ◽  
A. J. Banday ◽  
K. M. Górski
Keyword(s):  
Cosmic Microwave Background ◽  
Microwave Background ◽  
Independent Test ◽  
Model Independent

scholarly journals Disentangling QCD and new physics in D → πℓ+ℓ−

2021 ◽  
Vol 2021 (4) ◽  
Author(s):  
Aoife Bharucha ◽  
Diogo Boito ◽  
Cédric Méaux
Keyword(s):  
Standard Model ◽  
Branching Ratio ◽  
Branching Ratios ◽  
New Physics ◽  
Operator Product ◽  
Beyond The Standard Model ◽  
Spectral Functions ◽  
The Standard Model ◽  
Model Independent ◽  
Weak Annihilation

Abstract In this paper we consider the decay D+ → π+ℓ+ℓ−, addressing in particular the resonance contributions as well as the relatively large contributions from the weak annihilation diagrams. For the weak annihilation diagrams we include known results from QCD factorisation at low q2 and at high q2, adapting the existing calculation for B decays in the Operator Product Expansion. The hadronic resonance contributions are obtained through a dispersion relation, modelling the spectral functions as towers of Regge-like resonances in each channel, as suggested by Shifman, imposing the partonic behaviour in the deep Euclidean. The parameters of the model are extracted using e+e− → (hadrons) and τ → (hadrons) + ντ data as well as the branching ratios for the resonant decays D+ → π+R(R → ℓ+ℓ−), with R = ρ, ω, and ϕ. We perform a thorough error analysis, and present our results for the Standard Model differential branching ratio as a function of q2. Focusing then on the observables FH and AFB, we consider the sensitivity of this channel to effects of physics beyond the Standard Model, both in a model independent way and for the case of leptoquarks.

Sign in / Sign up

Export Citation Format

Share Document