International Journal of Modern Physics A

A high-power superconducting linac with an energy of 30MeV and a beam current of 100mA has been proposed and designed. The primary challenge lies in beam loss control and a robust lattice structure to ensure stable operation. This paper discusses the physics design study, design principles and simulation results considering machine errors. Extensive multiparticle simulations (a cumulative statistic of $1\times 10^5$ macroparticles) demonstrated that this linac, operating at 100mA, could maintain beam losses lower than 1W/m in error scenarios.

From a background of the Lorentz symmetry violation determined by a fixed time-like four-vector, a nonuniform electric field and a uniform magnetic field, we show that a relativistic Landau-type quantization can be achieved. We also analyze this relativistic Landau-type system under the influence of an infinity wall. Then, from the energy eigenvalues, we discuss the magnetization and the magnetic susceptibility at zero temperature.

We consider a minimal renormalizable non-supersymmetric $E_6$ Grand Unified Theory using fundamental representation 27 for fermions and scalars. The scalar with adjoint representation 78 is also taken for direct breaking of $E_6$ to SM. The proposed model, guided by TeV-scale vector-like fermions and scalar leptoquark, offers successful gauge unification even in the absence of any intermediate symmetry. Embedded with threshold corrections, it is shown to be compatible with the present experimental limit on proton decay lifetime. The unique feature of the model shows that the GUT threshold corrections to the unification mass is controlled by superheavy gauge bosons only, thereby minimizing the uncertainty of the GUT predictions. The scalar leptoquark and vector-like fermions residing in 27 representation can explain flavor physics anomalies like $R_{D^{(\ast )}}$ as reported by the LHCb collaboration and the muon anomalous magnetic moment reported by the recent muon $g-2$ experiment at Fermilab. The model can also predict a sub-eV scale neutrino at one-loop level via exchange of W and Z gauge bosons through MRIS mechanism.

We explore the application of nonextensive Bose statistics to describe the behavior of an ideal gas near the horizon of black holes, presenting a compelling case for its efficacy as an effective theory for interacting bosons. The central focus is on the careful selection of a nonextensive parameter, a critical aspect that enables the derivation of the correct entropy on the black hole horizon. Remarkably, this approach aligns with the well-established Bekenstein–Hawking entropy, showcasing the utility of nonextensive Bose statistics in capturing the thermodynamic properties of particles near black hole horizons. The study contributes to our understanding of fundamental interactions in extreme gravitational environments and provides a novel perspective on the statistical mechanics of black hole thermodynamics.

Experiments were performed in vacuum to examine a modified Kaluza–Klein theory. Originally proposed by Mbelek and Lachièze-Rey, the 5D Kaluza–Klein-$\psi$ theory includes an external scalar field $\psi$ to couple gravitational and electromagnetic fields and can be used to explain some misunderstood phenomena in physics. The theory predicts that a pendulum will experience detectable forces exceeding predictions from classical electromagnetism when interacting with a scalar field. In this experiment, a dielectric mirror is hung as a pendulum inside a vacuum chamber and its oscillations are examined with two laser interferometers. In proximity to the pendulum, different solenoids and toroids will induce magnetic fields that can also be shielded to a great extent using a Gauss chamber. The experiments were conducted in a vacuum chamber to allow the measurement of torsion angles as low as 0.1arcsec above the noise, as well as 0.1$\mu$m translations of the pendulum. The phenomenon observed differs from what was observed by Mbelek at ambient pressure in both magnitude and behavior. Dummy test results hint at the presence of convection effects to explain the pendulum’s rotation, which was eliminated under higher vacuum and by placing a wall between the solenoid and pendulum. In the presence of stronger magnetic fields, the pendulum’s translation was observed to agree with effects predicted by a consideration of diamagnetic effects.

Recently, it has been shown that the theory in the quadratic gauge on 4-sphere, ${𝕊}^4$ consists of two phases namely, the confined and the deconfined phases. A suitable finite field-dependent Becchi–Rouet–Stora–Tyutin (FFBRST) transformation interrelates two different gauge fixed theories. In this paper, we use the FFBRST technique on the curved space for the first time and elaborate a novel application of it. We propose two different formulations of this technique that transform the deconfined phase action on sphere to the confined phase action on sphere inside the quadratic gauge. Both proposed passages change the phase with BRST invariance to the phase without BRST invariance unlike usual connections where the FFBRST operation leaves the BRST symmetry intact and there is a unique field theoretic essence of them, which makes them particularly important to study. Thus, the two different field redefinitions act as a new mechanism that execute phase transition between two real QCD phases on 4-sphere other than ghost condensation process.

In this paper, we continue the project of systematic construction of invariant differential operators (IDOs) on the example of the noncompact algebras $sp(n,1)$. Our choice of these algebras is motivated by the fact that they belong to a narrow class of algebras, which are of split rank one, of which class the other cases were studied, some long time ago. We concentrate on the case $n=2$. We give the main multiplets and the main reduced multiplets of indecomposable elementary representations (ER) for, including the necessary data for all relevant invariant differential operators. We also present explicit expressions for the singular vectors and the intertwining differential operators.

Recently, Rajagopal et al. presented an asymptotically AdS black hole metric whose thermodynamics qualitatively mimics the behavior of the Van der Waals fluid by treating the cosmological constant as a thermodynamic pressure. In some studies in the literature, authors have discussed the effects of deformed algebras such as generalized and extended uncertainty principles on the thermal quantities of these black holes. In this paper, we considered another deformation, the rainbow gravity formalism, and we investigated its impact on the Van der Waal black hole thermodynamics. To this end, we first generated the modified lapse and mass functions, and then we derived the modified thermal quantities such as thermodynamic volume, Hawking temperature, entropy, and specific heat functions. Finally, we explored the thermodynamics of a black hole, which mimics the thermodynamics of an ideal gas, under the influence of the rainbow gravity formalism.