Constrain the Jerk Parameters with DESI 2024 Data

Abstract The deceleration coefficient q and the jerk coefficient j obtained by the Taylor expansion of the scale factor a ( t ) play an important role in the study of cosmology. The current value of these coefficients for a cosmological model reflects the transition time between the phases dominated by dark energy and matter and can be used to determine if and how much the universe is decelerating. Thus, these coefficient values offer a way of constraining a particular cosmology model. Research based on this scenario was completed by Orlando Luongo and Marco Muccino. However, some approaches in this method should be tested prudently because some conditions such as <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mstyle displaystyle="false"> <mml:mfrac> <mml:mrow> <mml:msub> <mml:mrow> <mml:mi mathvariant="italic">dd</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>L</mml:mi> </mml:mrow> </mml:msub> </mml:mrow> <mml:mrow> <mml:mi mathvariant="italic">dz</mml:mi> </mml:mrow> </mml:mfrac> </mml:mstyle> <mml:mo>&gt;</mml:mo> <mml:mn>0</mml:mn> </mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mstyle displaystyle="false"> <mml:mfrac> <mml:mrow> <mml:mi mathvariant="italic">dH</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="italic">dz</mml:mi> </mml:mrow> </mml:mfrac> </mml:mstyle> <mml:mo>&gt;</mml:mo> <mml:mn>0</mml:mn> </mml:math> may not be guaranteed. In this study, we used the MAPAge model to reconstruct the jerk parameters ( q 0 and j 0 ) with DESI 2024 data. Using the MAPAge model ensures particular physical circumstances are satisfied in the approach of determining the jerk parameters. Compared to the previous method, which used the Taylor expansion series q 0 , j 0 , and s 0 as model-independent parameters, we obtained more physical and slightly different results for the jerk parameters. Our results suggest that the DESI 2024 BAO data set favours different jerk parameters compared to the jerk parameters in the standard ΛCDM model.