hawking radiation Archives

August 22, 2024August 22, 2024 by Matt Williams

New Study Proposes how a Black Hole in Orbit Around a Planet Could be a Sign of an Advanced Civilization.

Ray traced shadow of a spinning and charged black hole. Credit: Simon Tyran, CC BY-SA 4.0

In 1971, English mathematical physicist and Nobel-prize winner Roger Penrose proposed how energy could be extracted from a rotating black hole. He argued that this could be done by building a harness around the black hole’s accretion disk, where infalling matter is accelerated to close to the speed of light, triggering the release of energy in multiple wavelengths. Since then, multiple researchers have suggested that advanced civilizations could use this method (the Penrose Process) to power their civilization and that this represents a technosignature we should be on the lookout for.

Examples include John M. Smart’s Transcension Hypothesis, a proposed resolution to the Fermi Paradox where he suggested advanced intelligence may migrate to the region surrounding black holes to take advantage of the energy available. The latest comes from Harvard Professor Avi Loeb, who proposed in a recent paper how advanced civilizations could rely on a “Black Hole Moon” to provide their home planet with power indefinitely. The way this black hole would illuminate the planet it orbits, he argues, would constitute a potential technosignature for future SETI surveys.

May 27, 2024May 27, 2024 by Evan Gough

Merging Black Holes Could Give Astronomers a Way to Detect Hawking Radiation

Simulation of merging supermassive black holes. Credit: NASA's Goddard Space Flight Center/Scott Noble — Simulation of merging supermassive black holes. New research shows how dark matter overcomes the Final Parsec Problem. Credit: NASA's Goddard Space Flight Center/Scott Noble

Nothing lasts forever, including black holes. Over immensely long periods of time, they evaporate, as will other large objects in the Universe. This is because of Hawking Radiation, named after Stephen Hawking, who developed the idea in the 1970s.

The problem is Hawking Radiation has never been reliably observed.

May 4, 2024May 4, 2024 by Brian Koberlein

The Universe Could Be Filled With Ultralight Black Holes That Can't Die

This simulated image shows how black holes bend a starry background and capture light. Credit: NASA’s Goddard Space Flight Center

It’s that time again! Time for another model that will finally solve the mystery of dark matter. Or not, but it’s worth a shot. Until we directly detect dark matter particles, or until some model conclusively removes dark matter from our astrophysical toolkit the best we can do is continue looking for solutions. This new work takes a look at that old theoretical chestnut, primordial black holes, but it has a few interesting twists.

June 9, 2023June 9, 2023 by Brian Koberlein

If Black Holes Evaporate, Everything Evaporates

How virtual particles radiate away from any mass. Credit: Wondrak, et al

Hawking radiation is one of the most famous physical processes in astronomy. Through Hawking radiation, the mass, and energy of a black hole escape over time. It’s a brilliant theory, and it means that black holes have a finite lifetime. If Hawking radiation is true. Because as famous as it is, Hawking radiation is unproven. The theory is not even theoretically proven.

March 16, 2022March 16, 2022 by Brian Koberlein

A new way to Confirm Hawking's Idea That Black Holes Give off Radiation

In honor of Dr. Stephen Hawking, the COSMOS center will be creating the most detailed 3D mapping effort of the Universe to date. Credit: BBC, Illus.: T.Reyes

Nothing can escape a black hole. General relativity is very clear on this point. Cross a black hole’s event horizon, and you are forever lost to the universe. Except that’s not entirely true. It’s true according to Einstein’s theory, but general relativity is a classical model. It doesn’t take into account the quantum aspects of nature. For that, you’d need a quantum theory of gravity, which we don’t have. But we do have some ideas about some of the effects of quantum gravity, and one of the most interesting is Hawking radiation.

October 20, 2021October 21, 2021 by Matt Williams

There are 6×10^80 Bits of Information in the Observable Universe

Since the beginning of the Digital Age (ca. the 1970s), theoretical physicists have speculated about the possible connection between information and the physical Universe. Considering that all matter is made up of information that describes the state of a quantum system (aka. quantum information), and genetic information is coded in our DNA, it’s not farfetched at all to think that physical reality can be expressed in terms of data.

This has led to many thought experiments and paradoxes, where researchers have attempted to estimate the information capacity of the cosmos. In a recent study, Dr. Melvin M. Vopson – a Mathematician and Senior Lecturer at Portsmouth University – offered new estimates of how much information is encoded in all the baryonic matter (aka. ordinary or “luminous” matter) in the Universe.

September 14, 2021September 14, 2021 by Brian Koberlein

We Knew Black Holes Have a Temperature. It Turns out They Also Have a Pressure

Artist view of an active supermassive black hole. Credit: ESO/L. Calçada

In the classical theory of general relativity, black holes are relatively simple objects. They can be described by just three properties: mass, charge, and rotation. But we know that general relativity is an incomplete theory. Quantum mechanics is most apparent in the behavior of tiny objects, but it also plays a role in large objects such as black holes. To describe black holes at a quantum level, we need a theory of quantum gravity. We don’t have a complete theory yet, but what know so far is that quantum mechanics makes black holes more complex, giving them properties such as temperature and perhaps even pressure.

July 5, 2021July 5, 2021 by Brian Koberlein

Hawking Made a Prediction About Black Holes, and Physicists Just Confirmed it

Computer simulation of plasma near a black hole. Credit: Hotaka Shiokawa / EHT

On its own, a black hole is remarkably easy to describe. The only observable properties a black hole has are its mass, its electric charge (usually zero), and its rotation, or spin. It doesn’t matter how a black hole forms. In the end, all black holes have the same general structure. Which is odd when you think about it. Throw enough iron and rock together and you get a planet. Throw together hydrogen and helium, and you can make a star. But you could throw together grass cuttings, bubble gum, and old Harry Potter books, and you would get the same kind of black hole that you’d get if you just used pure hydrogen.

January 24, 2021January 26, 2021 by Matt Williams

A New Idea to Harness Energy From Black Holes

Fifty years ago, English mathematical physicist and Nobel-prize winner Roger Penrose proposed that energy could be extracted from the space around a rotating black hole. Known as the ergosphere, this region lies just outside an event horizon, the boundary within which nothing can escape a black hole’s gravitational pull (even light). It is also here where infalling matter is accelerated to incredible speeds and emits all kinds of energy.

This became known as the Penrose Process, which many theorists have since expanded on. The latest comes from a study conducted by researchers from Columbia University and the Universidad Adolfo Ibáñez in Chile. With support from organizations like NASA, they demonstrated how a better understanding of the physics at work around spinning black holes could allow us to harness their energy someday.

April 23, 2019April 23, 2019 by Matt Williams

You Could Travel Through a Wormhole, but it’s Slower Than Going Through Space

Artist illustration of a spacecraft passing through a wormhole to a distant galaxy. Image credit: NASA.

Special Relativity. It’s been the bane of space explorers, futurists and science fiction authors since Albert Einstein first proposed it in 1905. For those of us who dream of humans one-day becoming an interstellar species, this scientific fact is like a wet blanket. Luckily, there are a few theoretical concepts that have been proposed that indicate that Faster-Than-Light (FTL) travel might still be possible someday.

A popular example is the idea of a wormhole: a speculative structure that links two distant points in space time that would enable interstellar space travel. Recently, a team of Ivy League scientists conducted a study that indicated how “traversable wormholes” could actually be a reality. The bad news is that their results indicate that these wormholes aren’t exactly shortcuts, and could be the cosmic equivalent of “taking the long way”!