Our current understanding of mass is based on the framework of modern physics, particularly the theory of relativity and the Standard Model of particle physics.
According to the theory of relativity, mass is a fundamental property of matter that measures the amount of resistance an object offers to changes in its motion. In this context, mass can be thought of as a measure of inertia—the tendency of an object to maintain its current state of motion.
In the realm of particle physics, the Standard Model describes mass as arising from interactions with the Higgs field. According to this model, particles gain mass by interacting with the Higgs field, which permeates all of space. The Higgs field is associated with a particle called the Higgs boson, which was discovered experimentally in 2012 at the Large Hadron Collider.
The Higgs mechanism provides a mechanism for particles to acquire mass and explains why some particles have different masses than others. The strength of the interaction between particles and the Higgs field determines the mass of the particles.
It's worth noting that our understanding of mass is still an active area of research. For example, the search for physics beyond the Standard Model is ongoing, as scientists aim to explain the nature of dark matter and reconcile gravity with quantum mechanics. Additionally, experimental efforts continue to study the properties of the Higgs boson and investigate potential new particles or phenomena related to mass.