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In the present investigation, we investigated the chemically reactive, laminar flow of a micropolar fluid over a stretching sheet in the presence of a transverse magnetic field, thermal radiation and the mutual effect of Soret–Dufour and viscous dissipation. The governing partial differential equations are converted into a system of nonlinear ordinary differential equations for finding the mathematical solutions and the transformed system is solved using the bvp4c algorithm in the MATLAB environment. Effects of different physical factors on dimensionless velocity, microrotation, temperature and concentration profiles are addressed and illustrated graphically. When the Schmidt number is low, it indicates that the momentum diffusivity dominates over the mass diffusivity.

The present work deals with warm inflationary scenario from the viewpoint of non-equilibrium thermodynamics. Due to the interacting two-fluid system, the dissipative mechanism in warm inflation can be considered as effective bulk viscous pressure in second-order non-equilibrium description of thermodynamics. It is found that the interaction term is proportional to the enthalpy density of the formed particles. The warm inflation has been analysed using slow-roll approximation and an expression for the interaction term has been obtained. The formulation of warm inflation in the non-equilibrium thermodynamical prescription has been presented as a lemma. Lemma 2 shows the inter-relation between slow-roll approximation and quasistable radiation bath using the Friedmann equations. Finally, warm inflation has been examined from the point of view of swampland conjectures.

This study explores the chiral magnetic effect (CME) in ultra-relativistic heavy-ion collisions. The CME, observed as back-to-back charge separation along the magnetic field axis, is investigated using the newly developed sliding dumbbell method (SDM) applied to Au(+)Au events at a centre-of-mass energy (sqrt{s}_{text {NN}}=) 200 GeV generated by the AMPT model with string melting configuration. The CME-like signal is externally injected in the events by flipping charges of pairs of particles perpendicular to the reaction plane. The study reports a significant enhancement of the CME-sensitive 3-particle (gamma ) correlator in events with high back-to-back charge separation, in a given collision centrality. Additionally, a linear relationship is observed between the (sqrt{|gamma |}) correlator for the same-sign charge pairs and positive charge asymmetry ((langle A^{+}rangle )) across the dumbbell in CME-enriched sub-samples. Furthermore, the fraction of CME in (Delta gamma ) (difference between the opposite and same sign (gamma ) correlators) is presented across different collision centralities having different percentages of externally injected CME-like signal. Overall, the research aims to understand and detect the CME through innovative experimental method and detailed analysis of the event structure.

The study aims at different families of analytical solutions and their dynamics for the ((2+1))-dimensional extended Boiti–Leon–Manna–Pempinelli (eBLMP) problem, which is widely used in the fields of physics such as non-linear optics, fluid dynamics, mathematical physics, plasma physics and quantum mechanics. The paper utilises two recently developed efficient mathematical methods: the generalised exponential rational function (GERF) method and the generalised Kudryashov (gK) method. These two methods are versatile, simply applicable to enlighten the new non-linear waveforms. Consequently, these discoveries enhance our understanding of complex systems like ((2+1))-dimensional eBLMP in the realm of non-linear science.

The multiple-relaxation-time (MRT) lattice Boltzmann method (LBM) is used in a suddenly expanded channel to demonstrate the flow of viscoplastic Bingham nanofluid with Al(_2)O(_3) nanoparticles. The geometry has two sections namely, inlet and outlet, and the corresponding heights are denoted by h and H, respectively. The length of the entire channel is 20H, and the expanded channel has a height of 16H. The purpose of the MRT-LBM simulation is to investigate the impact of changing the Bingham number (( 0 le Bn le 200)), keeping the Reynolds number (Re) fixed for different volume fractions ((phi =) 0.00 and 0.04). In addition, the consequences of variations in the Reynolds number (( 50 le Re le 1000 )) at constant Bingham number (Bn) are also studied for those two different volume fractions. The results demonstrate that with fixed (Bn=2), (Re=400) is the point where the flow pattern and recirculation regions are exactly the same for both volume fractions. An increase in Re causes the recirculation regions to grow for a fixed Bn for both volume fractions as Re’s rise increases the velocity and decreases the viscous force. Bn’s increment with Re and volume fraction unchanged lowers the recirculation region’s size due to a rise in viscous force. Higher Re and lower Bn cause the more significant recirculation regions to break down into smaller areas. Incrementing the volume fraction lowers size of the recirculation region. An unstable flow was observed for higher Bn (e.g., (Bn ge 100)) and lower Bn (e.g., (0 le Bn le 10)) when (Re ge 500) for both volume fractions in maximum cases. Unstable flow for lower Bn makes the recirculation regions asymmetric, and when Re is high, the recirculation regions break down for the base fluid ((phi =0.00)). When (Re=300) and (Bn=2), the length of the recirculation region of the upper wall decreases by (28.58%), and the length of the lower wall falls a bit less by (26.37%) when (phi ) is increased from 0.00 to 0.04. For (x/h=2), the nanoparticle mixed fluid’s velocity ((phi =0.04)) never gets a negative magnitude till the final position for (Re=700). In most situations, an increased volume fraction increases the skin-friction effect on both walls.

This paper explores the effectiveness of the Lie derivative discretisation scheme applied to two particular types of nonlinear dynamical equations, both of which have the characteristic of time variables in the denominator position. The discrete structure of non-autonomous systems is established. In particular, we exclude time variables as state variables to prevent non-autonomous systems from becoming autonomous systems. Using this method, we compute the numerical solution of the system above and compare it with the precise solution and the numerical findings of Runge–Kutta, demonstrating the broad applicability of the Lie derivative numerical algorithm. Finally, we determine the CPU consumption time of two numerical algorithms, thus providing evidence of the high efficiency of the Lie derivative numerical algorithm.

The self-energy in Born approximation including exchange of interacting one-dimensional systems is expressed in terms of a single integral about the potential which allows a fast and precise calculation for any potential analytically. The imaginary part of the self-energy as damping of single-particle excitations shows a rich structure of different areas limited by single-particle and collective excitation lines. The corresponding spectral function reveals a pseudogap, a splitting of excitations into holons and antiholons as well as bound states.

The current study investigates the three-dimensional radiative and convective Casson hybrid nanofluid flow and heat transfer with the Cattaneo–Christov heat flux model over an inclined spinning and extending disk subjected to an applied magnetic field. Additionally, the study considers the impacts of Joule’s heating and viscous dissipation. Mathematical modelling of the nanofluid flow problem containing Ag and multiwalled carbon nanotubes (MWCNT) nanoparticles with water as the base fluid in a Darcy medium is done using a cylindrical coordinate system. The simplified system of equations is subjected to the spectral quasilinearisation method (SQLM) approach for the graphical and tabular representations. Examining key parameters, such as magnetic field, Bejan number, angle of inclination, disk movement parameter and disk rotation reveals interesting results on velocity and temperature profiles. The research concludes that the Bejan number increases with higher values of temperature ratio, radiation and magnetic parameters, while it decreases with increasing Casson parameter and Brinkman number. Radial wall friction decreases with improved magnetic field, temperature ratio, stretching and porosity parameters, but tangential wall friction increases. The present results are compared with the one already existing in literature to validate the numerical scheme and the results are found to agree well with the previously published work. The application of hybrid nanofluid flow over rotating and stretching disks is widespread in various fields, including rotating machinery, electronic devices, patient treatment instruments, crystal growth method, etc.