Theoretical and phenomenological implications of fundamental principles in physics

The relentless quest for unraveling the true mechanisms that govern the Nature we observe and are part of have led physicists to rely on the adoption of fundamental principles. These assumptions have acted as a guiding light for the development of both theory and experiments since the moment in which Physics was born. Therefore, in order to further broaden the knowledge of the Universe surrounding us, it is natural to still have faith in the implications that a rational (though most of the times unexplainable) insight entails. The aim of this thesis is to provide a self-contained analysis centered around some of the most important physical principles we currently have at our disposal: general covariance, equivalence principle and Heisenberg uncertainty rela tions. However, the attention is not exclusively focused on the relevant consequences of the aforementioned concepts, as we also insist on the possibility of going beyond them, thus allowing for the existence of a novel phenomenology which can only be unfolded by means of new physics. .. [edited by Author]