We present a general framework to implement massive Nambu-Goldstone quasiparticles in driven many-body systems. The underlying mechanism leverages an explicit Lie group structure imprinted into an effective Hamiltonian that governs the dynamics of slow degrees of freedom; the resulting emergent continuous symmetry is weakly explicitly broken, giving rise to a massive Nambu-Goldstone mode, with a spectral mass gap scaling linearly with the drive period. We discuss explicit and experimentally implementable realizations, such as Heisenberg-like spin models that support gapped spin-wave excitations. We provide a protocol to certify the existence of the massive Nambu-Goldstone mode from the dynamics of specific observables, and analyze the dispersion spectrum and their lifetime in the presence of weak explicit symmetry breaking.

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• Goldstone bosons
• Quantum simulation
• Spin dynamics
• Floquet systems
• Nonequilibrium systems
• Classical spin chains