  Accretion-driven luminosity outbursts are a vivid manifestation of variable
mass accretion onto protostars. They are known as the so-called FU Orionis
phenomenon in the context of low-mass protostars. More recently, this process
has been found in models of primordial star formation. Using numerical
radiation hydrodynamics simulations, we stress that present-day forming massive
stars also experience variable accretion and show that this process is
accompanied by luminous outbursts induced by the episodic accretion of gaseous
clumps falling from the circumstellar disk onto the protostar. Consequently,
the process of accretion-induced luminous flares is also conceivable in the
high-mass regime of star formation and we propose to regard this phenomenon as
a general mechanism that can affect protostars regardless of their mass and/or
the chemical properties of the parent environment in which they form. In
addition to the commonness of accretion-driven outbursts in the star formation
machinery, we conjecture that luminous flares from regions hosting forming
high-mass star may be an observational implication of the fragmentation of
their accretion disks.
