{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T16:41:25Z","timestamp":1774543285325,"version":"3.50.1"},"reference-count":57,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2020,6,5]],"date-time":"2020-06-05T00:00:00Z","timestamp":1591315200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>The present study is devoted to explore the existence of a new family of compact star solutions by adopting the Karmarkar as well as Pandey\u2013Sharma condition in the background of     f ( R , T )     modified gravitational framework. For this purpose, we consider static spherically symmetric spacetime with anisotropic fluid distribution in absence of electric charge. In respect of Karmarkar condition, we assume a specific model of     g  r r      metric potential representing a new family of solutions which is also compatible with the Pandey\u2013Sharma condition. This assumed model permits us to calculate the     g  t t      component of metric tensor by making the use of Karmarkar condition. Further, we investigate the interior solutions for     V e l a  X \u2212 1      model of compact star by utilizing this new family of solutions for different values of parameter    \u03bb   . We have tuned the solution for     V e l a  X \u2212 1      so that the solutions matches the observed mass and radius. For the same star we have extensively discussed the behavior of the solutions. It is found that these solutions fulfill all the necessary conditions under the observational radii and mass attribute data for small values of parameter    \u03bb    and hence physically well-behaved and promising. Through graphical analysis, it is observed that our obtained analytical solutions are physically acceptable with a best degree of accuracy for     n \u2208 [ 1.8 , 7 ) \u2212 { 2 , 4 , 6 }    , where parameter n is involved in the discussed model. It is also noticed the causality condition is violated for all     n \u2265 7     and the tangential sound velocity     v t     is observed as complex valued for all     0 &lt; n &lt; 1.8    . Likewise, we explore these properties by considering large parameter    \u03bb    values. It is seen that the presented model violates all the physical conditions for     n \u2208 { 2 , 4 , 6 }    , while some of these for large values of    \u03bb   . Consequently, it can be concluded that the parameters n and    \u03bb    have a strong impact on the obtained solutions.<\/jats:p>","DOI":"10.3390\/sym12060962","type":"journal-article","created":{"date-parts":[[2020,6,9]],"date-time":"2020-06-09T06:34:16Z","timestamp":1591684456000},"page":"962","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":52,"title":["Physically Acceptable Embedded Class-I Compact Stars in Modified Gravity with Karmarkar Condition"],"prefix":"10.3390","volume":"12","author":[{"given":"Saira","family":"Waheed","sequence":"first","affiliation":[{"name":"Faculty of CORE Humanities, Prince Mohammad Bin Fahd University, Al Khobar 31952, Saudi Arabia"}]},{"given":"Ghulam","family":"Mustafa","sequence":"additional","affiliation":[{"name":"Department of Mathematics, Shanghai University, Shanghai 200444, China"}]},{"given":"Muhammad","family":"Zubair","sequence":"additional","affiliation":[{"name":"Department of Mathematics, COMSATS University Islamabad, Lahore Campus, Punjab 5459, Pakistan"}]},{"given":"Asifa","family":"Ashraf","sequence":"additional","affiliation":[{"name":"Jiangsu Key Labortary for NSLSCS, School of Mathematical Sciences, Nanjing Normal University, Nanjing 210023, China"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,5]]},"reference":[{"key":"ref_1","first-page":"424","article-title":"\u00dcber das Gravitationsfeld einer Kugel aus inkompressibler Fl\u00fcssigkeit nach der Einsteinschen Theorie","volume":"24","author":"Schwarzschild","year":"1916","journal-title":"Sitz. 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