The humankind perceives reality as the set of events of which are detectable by human senses. Although it is not possible to possess a full knowledge of everything, the human brain is capable of predicting the hidden constituents of the universe by performing algorithms on observations. Furthermore, the falsifiability of theoretical frameworks contributes to the flame of enthusiasm experienced by theorists. From this standpoint, this thesis focuses on the interconnection of gravitational phenomena and Planckian systems. The study examines the quantum nature of black holes, as well as the hypothetical astronomical objects commonly referred to as black branes or black strings within the context of Hawking radiation, which is the so-called black hole radiation. Since the background geometry is curved, it gives rise to an effective potential, which in turn results in a scattering process. Under this perspective, as an example, the linear stability of a (2 + 1)-dimensional Mandal-Sengupta-Wadia black hole is studied against small time-dependent perturbations. Subsequently, a (4 + 1)-dimensional dilatonic black string is considered and it is shown that there exists a resemblance between tachyonic particles and the fifth dimension, as the greybody factor evaluations only allowed for imaginary masses to be present. As the final step, a particular (3+1)-dimensional curved spacetime that might lead to experimental studies is considered: z = 2 Lifshitz-like black brane (which is also counted as a black hole) with hyperscaling violation. To analyze its radiation, we first tackle the problem with the tools of general relativity and derive its complete analytical blackbody radiation. Then, a particular holographic model is studied with the purpose of deriving its analytical dissipative properties: η ∝ T 3/2 , σDC ∝ T 3/2 , and ρDC ∝ T −3/2 which are the shear viscosity, the DC-conductivity, and the iii DC-resistivity, respectively. The aforementioned observables are achieved via the fluid/gravity correspondence, built upon the two-point correlation function GO+ (ω,0) = −iω= −iω r 4 + +ω 2 /3r+.The metric dynamic critical exponent is originally chosen as z = 2 in order for supporting superconducting fluctuations. However, this choice has also determined the characteristics of the dual model living on the three-dimensional boundary: a strongly-coupled, non-relativistic fluid exhibiting Lifshitz-like symmetry. Any possible confirmation of the theoretically-obtained dissipative parameters would act as a supplementary empirical evidence for the quantum properties of spacetime. Keywords: Hawking Radiation, Greybody Factor, Decay Rate, Absorption, Evaporation, Fluid/Gravity Correspondence, Hyperscaling Violation, Strongly-Coupled Fluid.
