Eddington-limited Accretion
Eddington-limited accretion is the maximum rate a black hole can grow before radiation pressure from infalling gas stops it, setting a hard ceiling on black hole mass in the early universe.
Eddington-limited accretion is the maximum sustainable rate at which a compact object, like a black hole, can accumulate mass before the outward radiation pressure from the infalling material balances the inward gravitational pull, halting further growth. This limit arises from the conservation of energy and momentum in high-energy astrophysical environments, defining the theoretical ceiling for black hole mass increase in the early universe.
What this means in real life
A black hole feeding on a nearby star can only swallow material so quickly before the intense heat and radiation from the infalling gas creates enough outward pressure to slow the feeding process, like a drain that can only handle so much water before backing up.
What it isn’t
It is not a hard physical barrier that stops accretion entirely—objects can exceed this rate under certain conditions (like when material arrives in clumpy streams rather than smoothly). It is also not specific to black holes alone; it applies to any compact object accreting material.
Commonly misused online
Often described as an absolute maximum that can never be exceeded, when in reality it is a theoretical equilibrium limit that can be surpassed if accretion geometry or material supply changes dramatically.
Based on 1 reference source, including primary sources. Last verified July 12, 2026.