In this thesis, we used Type 1a supernovas (SNeIa), calibrated with the local determination of the Hubble constant $H_0$ using the last result from the SH0ES collaboration, to build a continuous version of the Pantheon+ using Gaussian Process interpolation. This is done in a model-independent way. We use this new catalogue to predict the strong lensing distances from H0LiCOW and the Baryon Acoustic Oscillations distance ratios from DESI to test their compatibility. We found that these predictions using the Pantheon+ catalogue have a perfect agreement with the observational data from H0LiCOW and DESI, showing compatibility at a $1\sigma$ C.L. We showed that the agreement between the predicted observations using Pantheon+ and DESI BAO is highly dependent on the calibration of the sound horizon $r_d$. In particular, using the result from the Planck collaboration, we found that the predicted data would be at $2\sigma$ C.L. tension with the DESI BAO data. Our tests give further evidence that there are no significant unaccounted systematic errors that could bias the result from the SH0ES collaboration. Thus, we provide more evidence for the hypothesis that the Hubble constant tension problem has a physical origin.

In this thesis, we used Type 1a supernovas (SNeIa), calibrated with the local determination of the Hubble constant $H_0$ using the last result from the SH0ES collaboration, to build a continuous version of the Pantheon+ using Gaussian Process interpolation. This is done in a model-independent way. We use this new catalogue to predict the strong lensing distances from H0LiCOW and the Baryon Acoustic Oscillations distance ratios from DESI to test their compatibility. We found that these predictions using the Pantheon+ catalogue have a perfect agreement with the observational data from H0LiCOW and DESI, showing compatibility at a $1\sigma$ C.L. We showed that the agreement between the predicted observations using Pantheon+ and DESI BAO is highly dependent on the calibration of the sound horizon $r_d$. In particular, using the result from the Planck collaboration, we found that the predicted data would be at $2\sigma$ C.L. tension with the DESI BAO data. Our tests give further evidence that there are no significant unaccounted systematic errors that could bias the result from the SH0ES collaboration. Thus, we provide more evidence for the hypothesis that the Hubble constant tension problem has a physical origin.

Model-independent assessment of the compatibility of Supernovae and BAO measurements

NAJERA QUINTANA, JOSE ANTONIO DE JESUS
2023/2024

Abstract

In this thesis, we used Type 1a supernovas (SNeIa), calibrated with the local determination of the Hubble constant $H_0$ using the last result from the SH0ES collaboration, to build a continuous version of the Pantheon+ using Gaussian Process interpolation. This is done in a model-independent way. We use this new catalogue to predict the strong lensing distances from H0LiCOW and the Baryon Acoustic Oscillations distance ratios from DESI to test their compatibility. We found that these predictions using the Pantheon+ catalogue have a perfect agreement with the observational data from H0LiCOW and DESI, showing compatibility at a $1\sigma$ C.L. We showed that the agreement between the predicted observations using Pantheon+ and DESI BAO is highly dependent on the calibration of the sound horizon $r_d$. In particular, using the result from the Planck collaboration, we found that the predicted data would be at $2\sigma$ C.L. tension with the DESI BAO data. Our tests give further evidence that there are no significant unaccounted systematic errors that could bias the result from the SH0ES collaboration. Thus, we provide more evidence for the hypothesis that the Hubble constant tension problem has a physical origin.
2023
Model-independent assessment of the compatibility of Supernovae and BAO measurements
In this thesis, we used Type 1a supernovas (SNeIa), calibrated with the local determination of the Hubble constant $H_0$ using the last result from the SH0ES collaboration, to build a continuous version of the Pantheon+ using Gaussian Process interpolation. This is done in a model-independent way. We use this new catalogue to predict the strong lensing distances from H0LiCOW and the Baryon Acoustic Oscillations distance ratios from DESI to test their compatibility. We found that these predictions using the Pantheon+ catalogue have a perfect agreement with the observational data from H0LiCOW and DESI, showing compatibility at a $1\sigma$ C.L. We showed that the agreement between the predicted observations using Pantheon+ and DESI BAO is highly dependent on the calibration of the sound horizon $r_d$. In particular, using the result from the Planck collaboration, we found that the predicted data would be at $2\sigma$ C.L. tension with the DESI BAO data. Our tests give further evidence that there are no significant unaccounted systematic errors that could bias the result from the SH0ES collaboration. Thus, we provide more evidence for the hypothesis that the Hubble constant tension problem has a physical origin.
Dark Energy
Gaussian process
Precision Cosmology
File in questo prodotto:
File Dimensione Formato  
NajeraQuintana_JoseAntoniodeJesus.pdf

accesso aperto

Dimensione 1.32 MB
Formato Adobe PDF
1.32 MB Adobe PDF Visualizza/Apri

The text of this website © Università degli studi di Padova. Full Text are published under a non-exclusive license. Metadata are under a CC0 License

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.12608/71374