The classical theory builds too small holes
The first giant stars left black holes. So far, astronomers thought that the holes subsequently grew into the first supermassive black holes, but this theory cannot explain a new discovery that formed only 690 million years after the Big Bang.
THE FIRST STARS ARE LIT
180 million years after the Big 1 Bang, the first galaxies form. Dark matter attracts hydrogen, which is cooled and gives birth to huge stars, that almost only consist of hydrogen.
STARS EXPLODE INTO SUPERNOVAS
The giant stars live shorter 2 lives than modern stars. When they have consumed all the fuel in their cores via the fusion process, they explode into supernovas.
THE FIRST BLACK HOLES EMERGE
If a huge star is sufficiently 3 massive, its core is compressed into a black hole in the explosion. The holes weigh up to 100 solar masses.
GAS MAKES HOLES GROW
The black holes immediately 4 begin to grow bigger by their masses attracting gas from the surroundings. The bigger the black hole is, the more attraction it has.
SUPERMASSIVE HOLES ARE NOT BIG ENOUGH
690 million years after the Big 5 Bang, the holes have grown into supermassive black holes with masses of more than two million solar masses, but they are not monster- sized.
from the neighbouring galaxy could have split the molecules into atoms, which are better at holding on to the heat, so the gas is not cooled. Instead, the entire gas cloud becomes unstable, sending its mass towards the centre. The gravity from the high concentration of mass in the cloud’s core makes the matter contract very much, and the cloud finally collapses to give birth to a large seed corn.
According to the theory, the process particularly took place in small satellite galaxies, in which star formation was delayed in comparison to the mother galaxy. In such a system, radiation from the mother galaxy can easily reach the satellite galaxy and prevent the formation of stars. Instead, the satellite collapses into a medium black hole: a seed corn for an early monster hole.
New telescopes to find evidence
If the theory is correct, medium-sized black holes will shine like small, weak quasars, when, after a short while, gravity from the mother galaxy attracts the hole to consume the galaxy’s gas.
NASA’s new James Webb space telescope, which will be launched in 2012, stands a good chance of spotting radiation from the remote seed corns. It has a primary mirror of 6.5 m, almost three times bigger than the mirror of its predecessor, Hubble. So, the new space telescope has such sharp vision that it will probably be able to see the light from the old seed corns. The James Webb telescope’s chances of discovering them are improved by the fact that the telescope will be working within the wavelengths that the small quasars are believed to emit, as they grow. When a large seed corn of a million solar masses is absorbed by the mother galaxy and starts to consume gas, the black hole could in some cases consume so much gas so quickly that the hole’s mass exceeds the mass of all the stars in the mother galaxy combined for a brief period of time. A fat black hole will shine like a bright quasar and with a special signature in infrared wavelengths of 1-30 micrometres.
If James Webb spots the cosmic fingerprints of quasars with fat black holes, it will be evidence that the seed corns of the early monster holes were formed by large, collapsing gas clouds in the young universe.
Gravitational waves reveal holes
The theory could also be proved by means of astronomers’ new super tool: observations of gravitational waves.
Some of the seed corns of the first supermassive black holes probably collided in the young universe to emit gravitational waves, which are still flowing through space. Since 2016, the LIGO detectors in the US have captured gravitational waves from four collisons between black holes the size of stars. Unfortunately, gravitational waves from collisions between medium and supermassive black holes have wavelengths of 100,000+ km, and consequently, the waves are too long for detectors on Earth to capture.
So, astronomers must wait until 2034, when ESA launches the LISA space detector, to capture long gravitational waves from collisions between supermassive black holes. The system consists of three satellites placed in a triangle with five million km in between them. When gravitational waves from a collision between two supermassive holes flow through the triangle, the satellites shift slightly in relation to each other, which can be measured with laser beams.
Within two decades and based on observations made by the James Webb space telescope and measurements by the LISA detector, scientists could have solved the mystery of the origin of the universe’s oldest known object.