Scientists have confirmed Stephen Hawking's 50-year-old black hole area theorem by analyzing gravitational wave data from a black hole merger event, GW250114, which took place approximately 1.3 billion light-years away.

The event involved two black holes merging into a larger one, with the combined surface area increasing from about 93,700 to 154,500 square miles, surpassing the sum of their individual areas and validating Hawking's prediction.

This detection supports Hawking’s second law of black hole mechanics, which states that the surface area of a black hole cannot decrease after a merger, aligning with the principles of thermodynamics.

The observation was made on January 14 by LIGO, with the gravitational waves being twice as loud as any previous detection, allowing for unprecedented precision in measuring the black holes' properties.

Analysis of the gravitational waves' pitch and duration provided higher precision evidence than earlier tentative confirmations, confirming the increase in the event horizon's area with near certainty.

The black holes involved were each about 30 to 40 times the mass of the Sun, and the event's 'ringdown' confirmed the black hole's increased surface area, consistent with Hawking's theorem.

The detection also reaffirmed that black holes with the same mass and spin are mathematically identical, in accordance with the Kerr metric established in the 1960s.

Upgraded LIGO detectors, now three times more sensitive than in 2015, played a crucial role in capturing these detailed gravitational wave signals, paving the way for observing more distant and earlier black hole mergers.

Future plans include expanding detection capabilities through collaborations with European and Japanese observatories, as well as upcoming projects like LIGO-India, the Cosmic Explorer, and the Einstein Telescope.

These advancements aim to deepen our understanding of black hole physics and quantum gravity by enabling scientists to observe earlier and more remote mergers across the universe.

Overall, this discovery not only confirms a fundamental aspect of black hole thermodynamics but also demonstrates the power of gravitational wave astronomy in testing the laws of physics.