Do black holes exist? Or are they really 'dark energy stars'?
A Lawrence Livermore National Laboratory physicist challenges accepted theories about massive compact astrophysical objects
In the 1979 movie "The Black Hole," the crew of the Palamino spaceship passes through a black hole and enters a world of confusion where space and time are warped.
But in reality, if the crew approached the surface of a compact object, which Einstein's theory of general relativity would identify as a black hole, they would all disintegrate, according to Lawrence Livermore National Laboratory physicist George Chapline.
Chapline says that ordinary matter would break apart because the protons and neutrons in the matter would disintegrate. Further, Chapline says black holes do not really exist. Instead, he proposes that the mass of compact astrophysical objects consists of the same dark energy that makes up 60 percent of the mass of the universe.
According to general relativity, a black hole results from the death of a massive star and its eventual collapse under its own gravity to a single point; space and time switch places inside a boundary called an "event horizon." Quantum mechanics, however, dictates that space and time continue to play their usual roles inside compact objects, causing a whole barrage of strange behavior - behavior that Chapline says occurs in a dark energy star as well as on Earth when studying quantum critical phenomena. In such phenomena, small changes in the external conditions of a material can cause dramatic and anomalous subatomic changes, called quantum phase transitions, in the material's properties.
"There has never been direct evidence of a black hole," said Chapline, while acknowledging there are objects that general relativity would predict are black holes at the centers of galaxies. "Ironically, Einstein also didn't believe in black holes even though he created general relativity.
"Quantum critical phase transitions are not just possible but have actually been seen in the Laboratory," he said.
High temperature superconductivity is an example of quantum critical behavior. Chapline said that plutonium may be another example of an earthly quantum critical system; indeed it is the only example of a pure element that displays quantum critical behavior.
Just how general relativity and quantum mechanics are incompatible has intrigued Chapline for more than 20 years. But it wasn't until the summer of 2000 when Chapline was working on an assignment at Los Alamos National Laboratory that he ran into Nobel laureate and former Livermore physicist Robert Laughlin and the two discussed how a quantum phase transition could represent a surface where time stands still.
Chapline and Laughlin pointed out how the behavior of space-time in dark energy stars is very similar to how a superfluid confined to a vertical column might behave. The pressure in the superfluid increases with depth, and if at a certain depth, the speed of sound vanishes - sound is trapped in the fluid - then the physical behavior would be indistinguishable from the event horizon of a classical black hole, Chapline said.
"The key is that when the speed of sound goes to zero it's a signature of quantum criticality," he said. "When sound waves cross this surface, there are very dramatic physics effects."
In a dark energy star, however, Chapline said elementary particles, such as photons, electrons, or quarks, crossing over the quantum critical surface - which replaces the event horizon in a classical black hole - will morph into particles with a large mass and become unstable. Inside the dark energy star, space-time is just like normal space-time except that the vacuum energy inside is much larger than the cosmological vacuum energy outside the star.
And though his theory has string theorists and general relativists scratching their heads, Chapline sees a future that might just offer an alternate explanation of what happened during the Big Bang.
"This does go against the mainstream predictions of general relativists," he said. "When I came up with this idea, people just thought I was crazy for many, many years. But in 10 years, this will be the orthodox belief. This explanation of dark energy stars will help explain dark matter. This could profoundly change our whole view of the universe."