Sonic black holes produce “Hawking radiation,” may confirm famous theory

Sonic black holes produce “Hawking radiation,” may confirm famous theory

Enlarge / Simulated view of a black hole in front of the Large Magellanic Cloud. (credit: Wikimedia Commons/Alain r)

Israeli physicists think they have confirmed one of the late Stephen Hawking’s most famous predictions by creating the sonic equivalent of a black hole out of an exotic superfluid of ultra-cold atoms. Jeff Steinhauer and colleagues at the Israel Institute of Technology (Technion) described these intriguing experimental results in a new paper in Nature.

The standard description of a black hole is an object with such a strong gravitational force that light can’t even escape once it moves behind a point of no return known as the event horizon. But in the 1970s, Hawking demonstrated that—theoretically, at least—black holes should emit tiny amounts of radiation and gradually evaporate over time.

Blame the intricacies of quantum mechanics for this Hawking radiation. From a quantum perspective, the vacuum of space

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LIGO may have spotted a black hole-neutron star merger

LIGO may have spotted a black hole-neutron star merger

Enlarge / Our gravitational wave detectors really are a series of tubes. (credit: Caltech/MIT/LIGO Lab)

On April 1, the teams behind the three gravitational wave detectors started them up for a new observational run, the first with all three operating in parallel for the full run. With the benefit of three detectors and some upgrades that were done during the downtime, we’re seeing a flood of new data. In just one month, LIGO/VIRGO has seen five gravitational wave events. Three of those are from merging black holes, one was the second neutron star merger, and another may have been the first instance of a neutron star-black hole merger.

A new season

The two LIGO detectors have been a work in progress for years, starting with an early version that everyone acknowledged was unlikely to pick up gravitational waves. But each iteration has allowed scientists to understand the sources of

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