{"title":"Modified f(Q,C) gravity dark energy models with observational constraints","authors":"Dinesh Chandra Maurya","doi":"10.1142/s0217732324500342","DOIUrl":null,"url":null,"abstract":"<p>We investigate an isotropic and homogeneous flat dark energy model in <span><math altimg=\"eq-00003.gif\" display=\"inline\" overflow=\"scroll\"><mi>f</mi><mo stretchy=\"false\">(</mo><mi>Q</mi><mo>,</mo><mi>C</mi><mo stretchy=\"false\">)</mo></math></span><span></span> gravity theory that is linear in non-metricity <i>Q</i> and quadratic in boundary term <i>C</i> as <span><math altimg=\"eq-00004.gif\" display=\"inline\" overflow=\"scroll\"><mi>f</mi><mo stretchy=\"false\">(</mo><mi>Q</mi><mo>,</mo><mi>C</mi><mo stretchy=\"false\">)</mo><mo>=</mo><mi>Q</mi><mo>+</mo><mi>α</mi><msup><mrow><mi>C</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span><span></span>, where <span><math altimg=\"eq-00005.gif\" display=\"inline\" overflow=\"scroll\"><mi>α</mi></math></span><span></span> is a model parameter. We have solved the field equations in flat Friedmann–Lemaitre–Robertson–Walker (FLRW) spacetime geometry and considered a relation in the form of Hubble function in total energy density parameters <span><math altimg=\"eq-00006.gif\" display=\"inline\" overflow=\"scroll\"><msub><mrow><mi mathvariant=\"normal\">Ω</mi></mrow><mrow><mi>m</mi><mn>0</mn></mrow></msub></math></span><span></span>, <span><math altimg=\"eq-00007.gif\" display=\"inline\" overflow=\"scroll\"><msub><mrow><mi mathvariant=\"normal\">Ω</mi></mrow><mrow><mn>0</mn><mo stretchy=\"false\">(</mo><mi>Q</mi><mo>,</mo><mi>C</mi><mo stretchy=\"false\">)</mo></mrow></msub></math></span><span></span>, and Hubble constant <span><math altimg=\"eq-00008.gif\" display=\"inline\" overflow=\"scroll\"><msub><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span><span></span>. We have compared our results with two observational datasets <span><math altimg=\"eq-00009.gif\" display=\"inline\" overflow=\"scroll\"><mi>H</mi><mo stretchy=\"false\">(</mo><mi>z</mi><mo stretchy=\"false\">)</mo></math></span><span></span> and Pantheon SNe Ia datasets by using MCMC analysis and have obtained the best fit present values of parameters. We have used these best fit values throughout in result analysis and discussion. We have found the equation of state (EoS) parameter as <span><math altimg=\"eq-00010.gif\" display=\"inline\" overflow=\"scroll\"><mo>−</mo><mn>1</mn><mo>≤</mo><mi>ω</mi><mo>≤</mo><mn>0</mn><mo>.</mo><mn>2</mn></math></span><span></span> over <span><math altimg=\"eq-00011.gif\" display=\"inline\" overflow=\"scroll\"><mo>−</mo><mn>1</mn><mo>≤</mo><mi>z</mi><mo>≤</mo><mn>3</mn></math></span><span></span>. We have also investigated the Om diagnostic function and present age of the universe for these two datasets.</p>","PeriodicalId":18752,"journal":{"name":"Modern Physics Letters A","volume":null,"pages":null},"PeriodicalIF":1.5000,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Modern Physics Letters A","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1142/s0217732324500342","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
引用次数: 0
Abstract
We investigate an isotropic and homogeneous flat dark energy model in gravity theory that is linear in non-metricity Q and quadratic in boundary term C as , where is a model parameter. We have solved the field equations in flat Friedmann–Lemaitre–Robertson–Walker (FLRW) spacetime geometry and considered a relation in the form of Hubble function in total energy density parameters , , and Hubble constant . We have compared our results with two observational datasets and Pantheon SNe Ia datasets by using MCMC analysis and have obtained the best fit present values of parameters. We have used these best fit values throughout in result analysis and discussion. We have found the equation of state (EoS) parameter as over . We have also investigated the Om diagnostic function and present age of the universe for these two datasets.
期刊介绍:
This letters journal, launched in 1986, consists of research papers covering current research developments in Gravitation, Cosmology, Astrophysics, Nuclear Physics, Particles and Fields, Accelerator physics, and Quantum Information. A Brief Review section has also been initiated with the purpose of publishing short reports on the latest experimental findings and urgent new theoretical developments.