The question of what is more fundamental, mass or energy/light, is a complex one that has been the subject of scientific investigation and philosophical debate. In the framework of modern physics, both mass and energy are considered fundamental properties of the universe, and they are intimately related through Einstein's mass-energy equivalence principle, expressed by the equation E = mc².
According to our current understanding of nature, particles and waves are different manifestations of the same underlying entities known as quantum fields. Quantum fields exist throughout spacetime and give rise to particles as discrete excitations or quanta of those fields. This particle-wave duality is a fundamental aspect of quantum mechanics.
In this context, mass can be viewed as a property associated with particles, while energy is a more general concept that encompasses both the kinetic and potential energy of particles as well as the energy carried by waves. Energy can exist in various forms, such as electromagnetic radiation (light), thermal energy, or potential energy stored in the interactions between particles.
As for how this relationship between mass and energy arose in nature, it is a consequence of the fundamental laws and principles governing the universe. Our current understanding, as described by theories like the Standard Model of particle physics and general relativity, suggests that the properties of mass and energy emerge from the interactions and behavior of fundamental fields and particles.
It's important to note that our understanding of these fundamental concepts is continually evolving, and ongoing research in theoretical physics aims to refine our understanding of the fundamental nature of mass, energy, and their interconnections.