Yes, in quantum mechanics, it is possible to describe many quantum mechanical particles using a single wave packet. This is known as an entangled state or a many-particle wave function. The wave packet represents the collective behavior of the particles and contains information about their positions, momenta, and other properties.
When particles are entangled, their wave functions become correlated in such a way that the state of one particle is intimately connected to the state of the other particles. This correlation allows for a unified description of the entire system using a single wave function. The behavior of each individual particle can then be understood in terms of the properties of the collective wave function.
It's important to note that the description of many-particle systems can become mathematically complex as the number of particles increases, making exact calculations challenging. However, various techniques and approximations are employed to study such systems and understand their behavior.