Quasi-Stars: Black Holes Inside Giant Stars ⚡ экспресс
Numerical modeling of star cluster formation at densities typical of proto-globular clusters at high redshifts (z>6–10) shows that a cascade of stellar collisions can produce extremely massive stars (EMSs, >1000 M⊙), supermassive stars (SMSs, >10000 M⊙), and potentially intermediate-mass black holes. Direct calculations incorporating post-Newtonian dynamics of black holes and stellar evolution demonstrate that in environments with surface density Σ_h ≳ 10^6 M⊙ pc⁻², stellar-mass black holes (≲60 M⊙), driven by rapid mass segregation and relaxation, can penetrate inside EMSs/SMSs and sink into their gaseous envelopes. This embedded black hole phase, akin to a quasi-star (QS), emerges as a natural stage in the formation of supermassive objects in the densest clusters. The duration of the QS phase exceeds the SMS lifetime by orders of magnitude, enabling sustained growth through collisions, and the capture of multiple black holes leads to the emergence of gravitational-wave sources.
In the early Universe, star clusters were so dense that they gave birth to giants the size of the Solar System. If such a giant had taken the place of the Sun, its edge would have reached as far as Jupiter. These stars sometimes swallowed small black holes. The black hole would sink into the core and begin to grow, turning the star into a ghostly glow — a quasi-star. Here's a surprising paradox: a quasi-star weighs as much as ten thousand Suns, yet its outer layers are so thin that it's almost transparent.
Such a cosmic ghost can live for hundreds of thousands of years, until the black hole inside gains colossal mass. These rare objects explain the mysterious red dots that the James Webb Space Telescope has found in distant galaxies. And if several black holes fall into the same star, their merger creates gravitational waves — ripples in spacetime, detected by instruments on Earth. Thus, the ancient light of ghost stars reveals the secrets of the birth of supermassive black holes.
🎯 A quasi-star weighs as much as 10,000 Suns, but its outer layers are so thin that it's almost transparent — a true cosmic ghost.