Rownak Kundu , Ujjal Debnath , Himanshu Chaudhary , G. Mustafa
{"title":"Gravitational lensing of dark energy models and ΛCDM using observational data in loop quantum cosmology","authors":"Rownak Kundu , Ujjal Debnath , Himanshu Chaudhary , G. Mustafa","doi":"10.1016/j.jheap.2024.07.013","DOIUrl":null,"url":null,"abstract":"<div><p>This paper investigates the accelerated cosmic expansion in the late Universe by examining two dark energy models, viscous modified Chaplygin gas (VsMCG) and variable modified Chaplygin gas (VMCG), within loop quantum cosmology alongside the ΛCDM model. The objective is to constrain cosmic parameters using the ΛCDM model and 30 of the latest <span><math><mi>H</mi><mo>(</mo><mi>z</mi><mo>)</mo></math></span> measurements from cosmic chronometers (CC), including Type Ia Supernovae, Gamma-Ray Bursts (GRB), Quasars, and 24 uncorrelated baryon acoustic oscillations (BAO) measurements across a redshift range from 0.106 to 2.33. The latest Hubble constant measurement from Riess in 2022 is included to enhance constraints. In the ΛCDM, VsMCG, and VMCG frameworks, best-fit parameters for the Hubble parameter (<span><math><msub><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>) and sound horizon (<span><math><msub><mrow><mi>r</mi></mrow><mrow><mi>d</mi></mrow></msub></math></span>) are obtained. The results highlight significant disparities between <span><math><msub><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span> and <span><math><msub><mrow><mi>r</mi></mrow><mrow><mi>d</mi></mrow></msub></math></span> values from late-time observational measurements, reflecting the known <span><math><msub><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span> and <span><math><msub><mrow><mi>r</mi></mrow><mrow><mi>d</mi></mrow></msub></math></span> tensions. The gravitational lensing optical depth of the two dark energy models is studied by plotting <span><math><mi>log</mi><mo></mo><mo>(</mo><mi>τ</mi><mo>(</mo><msub><mrow><mi>z</mi></mrow><mrow><mi>l</mi></mrow></msub><mo>)</mo><mo>/</mo><msubsup><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>3</mn></mrow></msubsup><msub><mrow><mi>τ</mi></mrow><mrow><mi>N</mi></mrow></msub><mo>)</mo></math></span> vs <span><math><msub><mrow><mi>z</mi></mrow><mrow><mi>l</mi></mrow></msub></math></span>. The probability of finding gravitational lenses (optical depth) in both models increases with lens redshift <span><math><msub><mrow><mi>z</mi></mrow><mrow><mi>l</mi></mrow></msub></math></span>. The change in optical depth behavior for different parameter constraints is graphically analyzed. A joint analysis of VsMCG and VMCG with ΛCDM is conducted. While the models diverge in the early Universe, they are indistinguishable at low redshift. Using the Akaike information criteria, the analysis indicates that neither dark energy model can be dismissed based on the latest observations.</p></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"43 ","pages":"Pages 239-247"},"PeriodicalIF":10.2000,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of High Energy Astrophysics","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2214404824000685","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
引用次数: 0
Abstract
This paper investigates the accelerated cosmic expansion in the late Universe by examining two dark energy models, viscous modified Chaplygin gas (VsMCG) and variable modified Chaplygin gas (VMCG), within loop quantum cosmology alongside the ΛCDM model. The objective is to constrain cosmic parameters using the ΛCDM model and 30 of the latest measurements from cosmic chronometers (CC), including Type Ia Supernovae, Gamma-Ray Bursts (GRB), Quasars, and 24 uncorrelated baryon acoustic oscillations (BAO) measurements across a redshift range from 0.106 to 2.33. The latest Hubble constant measurement from Riess in 2022 is included to enhance constraints. In the ΛCDM, VsMCG, and VMCG frameworks, best-fit parameters for the Hubble parameter () and sound horizon () are obtained. The results highlight significant disparities between and values from late-time observational measurements, reflecting the known and tensions. The gravitational lensing optical depth of the two dark energy models is studied by plotting vs . The probability of finding gravitational lenses (optical depth) in both models increases with lens redshift . The change in optical depth behavior for different parameter constraints is graphically analyzed. A joint analysis of VsMCG and VMCG with ΛCDM is conducted. While the models diverge in the early Universe, they are indistinguishable at low redshift. Using the Akaike information criteria, the analysis indicates that neither dark energy model can be dismissed based on the latest observations.
期刊介绍:
The journal welcomes manuscripts on theoretical models, simulations, and observations of highly energetic astrophysical objects both in our Galaxy and beyond. Among those, black holes at all scales, neutron stars, pulsars and their nebula, binaries, novae and supernovae, their remnants, active galaxies, and clusters are just a few examples. The journal will consider research across the whole electromagnetic spectrum, as well as research using various messengers, such as gravitational waves or neutrinos. Effects of high-energy phenomena on cosmology and star-formation, results from dedicated surveys expanding the knowledge of extreme environments, and astrophysical implications of dark matter are also welcomed topics.