The particle/wave duality is a fundamental concept in quantum mechanics, which states that particles, such as electrons or photons, can exhibit both wave-like and particle-like properties depending on the experiment or observation being conducted. This duality is not directly related to the concept of mass/energy.
However, mass and energy are related in the famous equation E=mc², derived by Albert Einstein as part of his theory of relativity. This equation shows that energy (E) and mass (m) are interchangeable and can be transformed into one another. In this context, mass can be considered a form of condensed energy.
It is important to note that the particle/wave duality and the relationship between mass and energy are distinct concepts, although both are integral to our understanding of the behavior of particles in the quantum realm and the relativistic effects on mass and energy.