Narrow Results

In this study, we discuss an analytical solution for a set of the Klein–Gordon (KG) oscillators’ energies through a correlation between the frequency of the KG-oscillators and the traversable wormhole (TWH) throat radius. Under such restricted parametric correlation (hence the notion of conditionally exact solvability is unavoidable in the process), we report the effects of throat radius, rainbow parameter, disclination parameter and oscillator frequency on the spectroscopic structure of a vast number of $(n,m)$-states (the radial and magnetic quantum numbers, respectively). In the process, we only use two loop quantum gravity motivated rainbow functions pairs. Only rainbow functions clearly and reliably fully adhere to the rainbow gravity model and secure Planck energy $E_p$ as the maximum possible energy for particles and anti-particles alike. Near the asymptotically flat upper and lower universes connected by the TWH, i.e. for the throat radius $r_0\gg 1$, the energies tend to cluster around the rest mass energies, i.e. $\left|E_{\pm }\right|\sim m_0$. Whereas, for $r_0\ll 1$, the energies tend to approach $\left|E_{\pm }\right|\le E_P$.

We study the thermodynamics of modified black holes proposed in the context of gravity's rainbow. A notion of intrinsic temperature and entropy for these black holes is introduced. In particular for a specific class of modified Schwarzschild solutions, their temperature and entropy are obtained and compared with those previously obtained from modified dispersion relations in deformed special relativity. It turns out that the results of these two different strategies coincide, and this may be viewed as a support for the proposal of deformed equivalence principle.

The kinematics of massive particles moving in rainbow spacetime is studied. We derive the equation of geodesics when the semiclassical effect of moving particles on the background is taken into account. In particular we show that in rainbow flat spacetime the trajectory of a freely falling particle remains unchanged which is still a straight line in energy-independent coordinate system. The implication to the Unruh effect in rainbow flat spacetime is also discussed.

We obtain a (5+1)-dimensional global flat embedding of modified Schwarzschild black hole in rainbow gravity. We show that local free-fall temperature in rainbow gravity, which depends on different energy $\omega$ of a test particle, is finite at the event horizon for a freely falling observer, while local temperature is divergent at the event horizon for a fiducial observer. Moreover, these temperatures in rainbow gravity satisfy similar relations to those of the Schwarzschild black hole except the overall factor $g(\omega )$, which plays a key role of rainbow functions in this embedding approach.

At the Planck scale of length $\sim 10^{-35}$ m where the energy is comparable with the Planck energy, the quantum gravity corrections to the classical background spacetime results in gravity’s rainbow or rainbow gravity. In this modified theory of gravity, geometry depends on the energy of the test particle used to probe the spacetime, such that in the low energy limit, it yields the standard general relativity. In this work, we study the thin-shell wormholes in the spherically symmetric rainbow gravity. We find the corresponding properties in terms of the rainbow functions which are essential in the rainbow gravity and the stability of such thin-shell wormholes are investigated. Particularly, it will be shown that there are exact solutions in which high energy particles crossing the throat will encounter less amount of total exotic matter. This may be used as an advantage over general relativity to reduce the amount of exotic matter.

In this paper, we consider three-dimensional massive gravity’s rainbow and obtain black hole solutions in three different cases of Born–Infeld, logarithmic, and exponential theories of nonlinear electrodynamics. We discuss the horizon structure and geometrical properties. Then, we study thermodynamics of these models by considering the first-order quantum correction effects, which appear as a logarithmic term in the black hole entropy. We discuss such effects on the black hole stability and phase transitions. We find that due to the quantum corrections, the second-order phase transition happens in Born–Infeld and logarithmic models. We obtain the modified first law of black hole thermodynamics in the presence of logarithmic corrections.

One of the staple objectives of theoretical physics is to establish a reliable theory of quantum gravity. To achieve this goal, some fundamental scales are proposed in the modern era, e.g. two scales are proposed in the Snyder–de Sitter model. These two scales relate to measurement limits of the position and momentum. In this paper, we study the thermodynamic properties of the higher-dimensional Schwarzschild black hole in the context of rainbow gravity in the Snyder–de Sitter model within the presence and absence of rainbow gravity and compare our results for $d=4$ with the results which are already derived in the previous literature [B. Hamil and B. C. Lütfüoğlu, Int. J. Geom. Methods Mod. Phys. 19, 2250047 (2022)]. We find the existence of the remnant temperature of the concerned black hole. Unlike the four-dimensional Schwarzschild black hole, the black hole in higher dimensions $(d>4)$ has two remnant temperatures. Moreover, we observe that in the rainbow gravity background a nonzero lower bound value of the temperature of the black hole exists. Finally, we analyze the thermal stability remnant conditions of the black hole by computing the heat capacity within this model.

This work analyzes the dynamical variables and information transfer of a collapsing string fluid in the theory of Rainbow gravity (RG). Modifications are made to the field equations for the anisotropic string fluid in spherical geometry with the necessary rainbow functions. We have calculated the radius and time when effective horizons formed. This calculation helps to estimate the time of the observer reaching the apparent horizon. Moreover, we have computed the dynamical variables concerning the string fluid including mass density, pressure and the string tension. The behavior of the dynamical quantities is presented graphically. It is found that the rainbow parameter $\eta$ affects the dynamical variables. The results enable us to understand the physics of a collapsing fluid and the information transfer in the collapsing scenario.

Theoretical physicists generally prefer to modify the general theory of relativity rather than avoiding the successful approaches that have been offered to us. Hence, the rainbow formalism of gravity, which is one of the most studied quantum gravity candidates in literature, has recently gained importance in the field. In this study, the energy–momentum localization problem is discussed for the Taub universe within the framework of rainbow gravity. To achieve this goal, energy and momentum components are calculated by making use of diverse values of rainbow functions in the Einstein, Bergmann–Thomson, Landau–Lifshitz, and the Papapetrou prescriptions for the geometry under consideration. Except for the Landau–Lifshitz prescription, all prescriptions depend on the rainbow functions and the momentum components vanish. Graphical analysis is performed for all the energies obtained. Also, it is shown in limiting condition $f_1(\chi )\to 1,f_2(\chi )\to 1$ that the results are compatible with the ones obtained in the general relativity.

The energy of a particle moving on a space–time, in principle, can affect the background metric. The modifications to it depend on the ratio of energy of the particle and the Planck energy, known as rainbow gravity. Here, we find the explicit expressions for the coordinate transformations from rainbow Minkowski space–time to accelerated frame. The corresponding metric is also obtained which we call as rainbow Rindler metric. So far we are aware of that no body has done it in a concrete manner. Here, this is found from the first principle and hence all the parameters are properly identified. The advantage of this is that the calculated Unruh temperature is compatible with the Hawking temperature of the rainbow black hole horizon, obtained earlier. Since the accelerated frame has several importance in revealing various properties of gravity, we believe that the present result will not only fill that gap, but also help to explore different aspects of rainbow gravity paradigm.

In this paper, we have studied the thermodynamic properties of charged AdS black hole with different dimensions under rainbow gravity. At first, by employing the Heisenberg uncertainty principle and the modified dispersion relation and analyzing the effect of rainbow gravity parameter $\eta$ and AdS radius $l$ on the thermodynamics and phase transformation, we have found that the phase structure is related to the AdS radius $l$ and the heat capacity behaviors are quite similar for different rainbow gravity parameters $\eta$ and different dimensions $d$. Then, for the rainbow gravity, introducing the analogy between the charged AdS black hole and liquid–gas systems and analyzing the critical behavior of the state equation for charged AdS black hole in different dimensions, the charged AdS black hole has Van der Waals-like phase transitions. At last, we have discussed the relationship between Gibbs free energy $G$ and Hawking temperature $T_h$ in different dimensions and found the typical dovetail behavior, which can be interpreted as a first-order phase transition for the charged AdS black hole under rainbow gravity.

Inspired by the pronounced effect of gravity’s Rainbow on black hole thermodynamics, entropy relations and bounds have been investigated for $d$-dimensional Reissner–Nordström (RN) black hole in the framework of Rainbow gravity. Basic thermodynamic properties of the black hole have been derived for the event horizon and Cauchy horizon. Except for the horizon radius, they all crucially depend on the Rainbow functions. Bounds of the aforesaid thermodynamic quantities have been deduced for both horizons. Analyzing the specific heat capacity, stability conditions have been obtained. Also, the extremal phase of the black hole has been explored. Further, a comparative study has been carried out to distinguish between the effects of Rainbow gravity model parameters on the entropy bound by considering different Rainbow gravity functions. For massless scalar perturbation, quasinormal modes have been computed using modified WKB approach. We have investigated the quantum correction of the black hole in a Rainbow gravity background to obtain the effects of Extended Uncertainty Principle (EUP) and Generalized Uncertainty Principle (GUP) parameters. We have derived the Hawking temperature, specific heat, entropy and remnant masses of the black hole in the Extended General Uncertainty Principle (EGUP) framework, and with the help of graphical methods, we have compared our findings.

The Duffin–Kemmer–Petiau (DKP) particle with spin 0 interacts with the Aharonov–Bohm (AB) magnetic vector potential and scalar Coulomb-type potential in the cosmic string space–times under the framework of rainbow gravity (RG). By using Bethe–Ansatz method, we obtain the energy eigenvalue and approximate solution to the wave function of the DKP particle with spin 0. We select two sets of rainbow functions and analyze their influence on the energy eigenvalue and wave functions. We find that the energy eigenvalue is determined by the parameters of the rainbow function. It further shows that the rainbow function affects the properties of the space–time where the DKP particle located, and also affects the distribution probability of DKP particles in the space.

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.

In this article, we explore the consequences in the calculation of deflection angle of photons, caused by a gravitational source of mass M, for the case of an energy dependent metric. We analyze the corrections to the standard Schwarzschild case for the weak and strong limits. In both cases, the corrections to the deflection angle are of the order ϵ/E_Pl, where E_Pl is the Planck energy and ϵ, the energy of the photon at spatial infinite. The corrections to the angular separation image is also of order ϵ/E_Pl, for the weak limit, while in the strong case there is a corrective term with the shape ϵ/E_Pl n e^2nπ for the relativistic image of order n. The amplification of the image is also discussed. Even if corrections are tiny, in both limits, we discuss the qualitative effects for different types of Lorentz invariance deformations.

According to Verlinde’s recent proposal, the gravity is originally an entropic force. In this paper, we obtain the corrections to the entropy-area law of black holes within rainbow gravity. The corrected entropy-area law leads to the modifications of the number of bits $N$. Inspired by Verlinde’s argument on the entropic force, and using the modified number of bits, we can investigate the effects of rainbow gravity on the modified Newtonian dynamics, Newton’s law of gravitation, and Einstein’s general relativity in entropic force approach.

Rainbow gravity can be a suitable model to study the Friedmann–Robertson–Walker (FRW) universe in the realm of high energy physics. In rainbow gravity the radius of the apparent horizon is modified and it is used to derive the surface gravity and the temperature on the horizon. Inspired by the modified Friedmann equation in rainbow gravity and adopting the viewpoint that there is a deep connection between Friedmann equation and the first law of thermodynamics, the entropy on the horizon is obtained. It is interesting to be noted that the thermodynamical properties of the FRW universe depend on the energy of the probe, which is used by an observer to investigate the spacetime. Finally, it is shown that the validity of the generalized second law (GSL) of thermodynamics can be considered as a useful instrument to restrict the choice of rainbow gravity functions.

In this paper, we study the relativistic and nonrelativistic Landau levels for Dirac fermions in the cosmic string spacetime in the context of rainbow gravity in $(3+1)$-dimensions, where we work with the curved Dirac equation with minimal coupling in cylindrical coordinates. Using the tetrads formalism of General Relativity, we obtain a second-order differential equation. Solving this differential equation, we obtain a generalized Laguerre equation as well as the relativistic Landau levels for the fermion and antifermion, where such energy levels are quantized in terms of the quantum numbers n, $m_j$ and $m_s$, and explicitly depends on the rainbow functions $f(\epsilon )$ and $g(\epsilon )$, charge parameter $\sigma$, cyclotron frequency ${\omega }_c$, curvature parameter $\alpha$, and on the square rest energy $m_0^2$ and square z-momentum $k_z^2$, respectively. Posteriorly, we study the nonrelativistic limit of the system, where we obtain the nonrelativistic Landau levels. In both cases (relativistic and nonrelativistic), we graphically analyze the behavior of Landau levels for the three-rainbow gravity scenarios as a function of the magnetic field B and of the curvature parameter $\alpha$. In addition, we also compared our problem with other works, where we verified that our results generalize several particular cases in the literature.

The explicit form of the field equations has been obtained by varying the action of the four-dimensional Einstein-dilaton gravity in the presence of the scalar-coupled exponential nonlinear electrodynamics. The exact black hole solutions of the field equations have been obtained in an energy-dependent spherically symmetric geometry. It has been found that the solution of the scalar field equation can be obtained by combining two Liouville potentials. We have introduced three types of exponentially charged dilatonic black holes and their thermodynamic properties have been studied noting the effects of rainbow functions. The impacts of rainbow functions on the conserved and thermodynamic quantities of the new black hole solutions have been explored. Through the Smarr mass formula, it has been demonstrated that the first law of black hole thermodynamics remains valid for either of the new rainbow black hole solutions. The quantum gravitational effects on the thermodynamic phase transition or thermal stability of the black holes have been studied by use of the canonical ensemble method. By calculating the black hole heat capacity, the type-1 and type-2 phase transition points and the conditions under which the exponentially charged rainbow black holes are locally stable have been identified.

In this study, we survey the generalized Duffin–Kemmer–Petiau oscillator containing a non-minimal coupling interaction in the context of rainbow gravity in the presence of the cosmic topological defects in space-time. In this regard, we intend to investigate relativistic quantum dynamics of a spin-0 particle under the modification of the dispersion relation according to the Katanaev–Volovich geometric approach. Thus, based on the geometric model, we study the aforementioned bosonic system under the modified background by a few rainbow functions. In this way, by using an analytical method, we acquire energy eigenvalues and corresponding wave functions to each scenario. Regardless of rainbow gravity function selection, the energy eigenvalue can present symmetric, anti-symmetric, and symmetry breaking characteristics. Besides, one can see that the deficit angular parameter plays an important role in the solutions.