[Black holes were thought to arise from the collapse of dead
stars. But a Webb telescope image showing the early universe hints at
an alternative pathway.]
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SUNDAY SCIENCE: HOW TO CREATE A BLACK HOLE OUT OF THIN AIR  
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Dennis Overbye
December 24, 2023
New York Times
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_ Black holes were thought to arise from the collapse of dead stars.
But a Webb telescope image showing the early universe hints at an
alternative pathway. _

A composite image showing the quasar UHZ-1. The X-ray data from the
Chandra X-ray Observatory is shown in purple; the galaxies and stars
are from infrared data from the James Webb Space Telescope., X-ray:
NASA/CXC/SAO/Ákos Bogdán; Infrared: NASA/ESA/CSA/STScI

 

How many ways are there to leave this universe?

Perhaps the best known exit entails the death of a star. In 1939 the
physicist J. Robert Oppenheimer and his student Harlan Snyder, of the
University of California, Berkeley, predicted that when a sufficiently
massive star runs out of thermonuclear fuel, it collapses inward and
keeps collapsing forever, shrink-wrapping space, time and light around
itself in what today is called a black hole.

But it turns out that a dead star might not be needed to make a black
hole. Instead, at least in the early universe, giant clouds of
primordial gas may have collapsed directly into black holes, bypassing
millions of years spent in stardom.

That is the tentative conclusion recently reached by a group of
astronomers studying UHZ-1, a speck of light dating from not long
after the Big Bang. In fact, UHZ-1 is (or was) a powerful quasar that
spat fire and X-rays from a monstrous black hole 13.2 billion years
ago, when the universe was not quite 500 million years young.

That is unusually soon, cosmically speaking, for so massive a black
hole to have come into being through stellar collapses and mergers.
Priyamvada Natarajan, an astronomer at Yale and the lead author of a
paper published in the Astrophysical Journal Letters
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in UHZ-1 they have discovered a new celestial species, which they call
an overmassive black hole galaxy, or O.B.G. In essence, an O.B.G. is a
young galaxy anchored by a black hole that became too big too fast.

The discovery of this precocious quasar could help astronomers solve a
related puzzle that has tantalized them for decades. Nearly every
galaxy visible in the modern universe seems to harbor at its center a
supermassive black hole millions of billions of times as massive as
the sun. Where did those monsters come from? Could ordinary black
holes have grown so large so fast?

Dr. Natarajan and her colleagues propose that UHZ-1, and so perhaps
many supermassive black holes, began as primordial clouds. These
clouds could have collapsed into kernels that were precociously heavy
— and were sufficient to jump-start the growth of overmassive black
hole galaxies. They are another reminder that the universe we see is
governed by the invisible geometry of darkness.

“As the first O.B.G. candidate, UHZ-1 provides compelling evidence
for the formation of heavy initial seeds from direct collapse in the
early universe,” Dr. Natarajan and her colleagues wrote. In an
email, she added: “Nature does seem to make BH seeds many ways,
beyond just stellar death!”

Daniel Holz, a theorist at the University of Chicago who studies black
holes, said: “Priya has found an extremely exciting black hole, if
true.”

He added, “It is simply too big too early. It’s like looking in at
a kindergarten classroom and there among all the 5-year-olds is one
that is 150 pounds and/or six feet tall.”

According to the story that astronomers have been telling themselves
about the evolution of the universe, the first stars condensed out of
clouds of hydrogen and helium left over from the Big Bang. They burned
hot and fast, quickly exploding and collapsing into black holes 10 to
100 times as massive as the sun.

Over eons, successive generations of stars were formed from the ashes
of previous stars, enriching the chemistry of the cosmos. And the
black holes left over from their deaths kept merging and growing
somehow, into the supermassive black holes at the centers of galaxies.

The James Webb Space Telescope, launched two years ago this Christmas,
was designed to test this idea. It possesses the biggest mirror in
space, 21 feet in diameter. More important, it was designed to record
infrared wavelengths from the light of the most distant and therefore
earliest stars in the universe.

But as soon as the new telescope was trained on the sky, it caught
sight of new galaxies so massive and bright that they defied
cosmologists’ expectations. Arguments have raged for the last couple
of years about whether these observations in fact threaten a
longstanding model of the cosmos. The model describes the universe as
composed of a trace of visible matter, astounding amounts of “dark
matter,” which provides the gravity to hold galaxies together, and
“dark energy,” pushing these galaxies apart.

The discovery of UHZ-1 represents an inflection point in these
debates. In preparation for a future observation by the James Webb
Space Telescope of a massive cluster of galaxies in the constellation
Sculptor, Dr. Natarajan’s team asked for time on NASA’s Chandra
X-ray Observatory. The cluster’s mass acts as a gravitational lens,
magnifying objects far behind it in space and time. The researchers
hoped to get a glimpse in X-rays of whatever the lens might bring into
view.

What they found was a quasar powered by a supermassive black hole
about 40 million times as massive as the sun. Further observations by
the Webb telescope confirmed that it was 13.2 billion light-years
away. (The Sculptor cluster is about 3.5 billion light-years away.) It
was the most distant and earliest quasar yet found in the universe.

“We needed Webb to find this remarkably distant galaxy, and Chandra
to find its supermassive black hole,” Akos Bogdan of the Center for
Astrophysics Harvard & Smithsonian said in a news release. “We also
took advantage of a cosmic magnifying glass that boosted the amount of
light we detected.”

The results indicate that supermassive black holes existed as early as
470 million years after the Big Bang. That isn’t enough time to
allow the black holes created by the first generation of stars —
starting out at 10 to 100 solar masses — to grow so big.

Was there another way to make even bigger black holes? In 2017 Dr.
Natarajan suggested that collapsing clouds of primordial gas could
have birthed black holes more than 10,000 times as massive as the sun.

“You can then imagine one of these subsequently growing into this
young, precociously large black hole,” Dr. Holz said. As a result,
he noted, “at every subsequent time in the universe’s history
there will always be some surprisingly large black holes.”

Dr. Natarajan said, “The fact that these start out in life
overmassive implies that they will likely eventually evolve into
supermassive black holes.” But no one knows how that works. Black
holes make up 10 percent of the mass in the early quasar UHZ-1,
whereas they compose less than one one-thousandth of a percent of the
mass of modern-day galaxies like the giant Messier 87, whose black
hole weighed in at 6.5 billion solar masses when its picture was
taken by the Event Horizon Telescope
[[link removed]] in
2019.

That suggests that complicated environmental feedback effects dominate
the growth and evolution of these galaxies and their black holes,
causing their mass in stars and gas to bulk up.

“So in effect these extremely early O.B.G.s are really telegraphing
much more information about, and illuminating, seeding physics rather
than later growth and evolution,” Dr. Natarajan said. She added:
“Though they have important implications.”

Dr. Holz said, “It would certainly be cool if it turns out to be
what’s happening, but I’m genuinely agnostic.” He added,
“It’s going to be a fascinating story no matter how we solve the
mystery of early big black holes.”

_Dennis Overbye: I’m the cosmic affairs correspondent for The New
York Times, covering physics and astronomy._

_What I Cover_

_I report with an eye toward big issues like the birth and death of
the universe, the fates of black holes, the fundamental laws of
nature, free will and quantum mysteries – how we learn about these
things and what it means for our status as ephemeral creatures in a
dynamic universe. I am intrigued by the fact that Albert Einstein, who
died almost 80 years ago, is increasingly relevant to the quandaries
of modern science._

_My Background_

_I’ve been doing this for almost 50 years, 25 of them at The Times.
I have a physics degree from M.I.T. After a year of graduate school in
astronomy, I spent four years as a writer and editor at Sky and
Telescope magazine. I have written two books: “Lonely Hearts of the
Cosmos, the Scientific Search for the Secret of the Universe”
(Little, Brown, 1999) and “Einstein in Love, a Scientific Romance”
(Viking-Penguin, 2000). In 2014 I was a finalist for the Pulitzer
Prize._

_Journalistic Ethics_

_Like all Times journalists, I am committed to upholding the standards
of integrity in our Ethical Journalism Handbook
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_Contact Me_

_I prefer to be contacted by email.
EMAIL: [email protected]
ANONYMOUS TIPS: nytimes.com/tips [[link removed]]
X (TWITTER): @overbye [[link removed]]
FACEBOOK: Dennis Overbye [[link removed]]_

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CENTRAL AMERICAN VOLCANOES OFFER CLUES TO EARTH’S GEOLOGICAL
EVOLUTION
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Q&A — GEOCHEMIST ESTEBAN GAZEL and PABLO FONSECA Q.
Along 1,100 kilometers, from Mexico to Costa Rica, lies the Central
American volcanic arc, where the variety of magma types make for a
geological paradise
KNOWABLE MAGAZINE
December 20, 2023

* Science
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* Black Holes
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* JWST
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