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Can anyone make a black hole in a laboratory? – Sohini B., age 13, Kolkata, West Bengal, India
A black hole is an object so massive and dense that even light cannot escape its gravity. They occur in space when extremely dense objects, such as the centers of stars, collapse.
All the black holes observed in space are the products of natural processes and are very far away.
NASA, ESA, CSA, Ralf Crawford (STScI)
As an astronomer, I study how black holes interact with their surroundings. Creating a black hole in a lab would be an amazing opportunity to learn more about how the universe works. But is it even possible?
What does it take to make a black hole?
Any amount of mass can be turned into a black hole if you cram it into a small enough space, but you would need an extremely high density, or mass per volume, to create one on Earth. Water has a density of 1 gram per cubic centimeter. That’s about 8 pounds per gallon. The densest common element, lead, is 11 times denser. That’s still nowhere near dense enough to make a black hole. To do so, gravity needs to overcome the very strong forces that create bonds inside atoms and give matter its structure.
Objects in space can be much, much denser than things on Earth. A massive dying star can collapse into a very dense object called a neutron star when the gravity of the star’s core overcomes the pushing force between atoms. When this phenomenon happens, all the matter in the neutron star fuses into one big atom, with a density of about a million billion g/cc. A single teaspoon of a neutron star is a thousand times heavier than the Great Pyramid of Giza in Egypt!
If a neutron star gets more massive and more dense, the forces that hold atoms together can finally surrender to gravity, and all the mass collapses inward. At some point, the speed needed to escape its gravity becomes greater than the speed of light, which means nothing can escape, and all the particles around the star get sucked inside. Instead of one big atom, it’s now a black hole.
A black hole with the mass of the Earth would have a radius of about half an inch, which is about the size of your thumb. Its density would be in the range of a billion billion billion g/cc.
The smallest artificial objects are tiny computer chips and biomedical devices 100 million times smaller than your thumb. If you could stuff a metric ton – 2,000 pounds, about the weight of a small car – of material into the smallest computer chip, that would get you a black hole.
Is this possible in a lab today?
In short, no. There is no way to artificially produce the huge densities described above. The densest everyday material is many millions of times less dense than what is needed to produce a tiny black hole.
When huge, underground particle accelerators are activated, people sometimes worry that they will create tiny black holes by colliding bits of matter at very rapid speeds. Don’t worry, black holes aren’t produced this way.
While some particle accelerators can create conditions as hot and dense as the big bang, they don’t produce black holes.
CERN
Would it be possible in the future?
It’s hard to know how technology will develop in the future, but the laws of physics are going to stay the same. Normal matter can’t be stuffed into a space tiny and dense enough without overcoming a huge outward pressure.
There is a loophole that some scientists think could get around this problem. Only some types of particles push against each other with outward pressure.
Some particles don’t resist being in the same space. You can stack as many of them as you like in a given volume. A particle of light, called a photon, is one such particle, so it’s conceivable that many, many photons could be focused at a single point and create the density needed to create a black hole.
MissMJ, Cush/Wikimedia Commons, CC BY
This type of black hole is called a “kugelblitz.” To create a kugelblitz, you’d need to convert a huge amount of mass directly into energy and then focus all that energy down onto a minute area of space. Some scientists think that powerful lasers could achieve this effect. Others say there’s no way to focus enough light. For now, this idea is still science fiction.
What would happen if scientists successfully created one?
Many people think that once something falls down a black hole, it’s gone forever, but most scientists think this is not the case. Stephen Hawking’s most famous theory was the idea that black holes gradually lose their mass. A small black hole would “evaporate” in this way very quickly.
Because any black hole created in a lab would be tiny, it would immediately evaporate in a flash of high-energy light. An artificial one would probably exist only for a fraction of a second before harmlessly disappearing.
So, the creation of an artificial black hole is impossible with our current technology, and it might be completely impossible due to the laws of physics. Still, thinking about black holes and how they would affect objects around them helps scientists understand the way the universe works.
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