This new study “changes not only our understanding of Hawking radiation but also our view of the universe and its future.”
While it was previously believed that the presence of an event horizon was a prerequisite for any occurrence of radiation, this study presents evidence challenging this notion, indicating that the existence of such a horizon is not obligatory.
New research conducted by Michael Wondrak, Walter van Suijlekom, and Heino Falcke from Radboud University has provided further evidence supporting Stephen Hawking’s theories on black holes, albeit with some nuanced insights.
The study confirms that black holes will indeed evaporate over time due to a phenomenon known as Hawking radiation. However, the significance of the event horizon, previously considered crucial, has been reevaluated.
It is now understood that gravity and the curvature of spacetime are responsible for this radiation as well. Consequently, this groundbreaking discovery suggests that all large celestial bodies, including stellar remnants, will eventually undergo evaporation.
By skillfully integrating principles from quantum physics and Einstein’s theory of gravity, Stephen Hawking posited that pairs of particles spontaneously emerge near the event horizon—a region beyond which escape from a black hole’s gravitational pull is impossible.
These particle-antiparticle pairs briefly materialize from the quantum field and swiftly annihilate one another. However, in certain instances, one particle may fall into the black hole while the other manages to escape, resulting in what is known as Hawking radiation. Hawking proposed that this process ultimately leads to the gradual evaporation of black holes.
In this latest research, conducted by scientists at Radboud University, a reexamination of a fundamental process was undertaken to determine the significance of an event horizon. By employing a multidisciplinary approach, incorporating principles from physics, astronomy, and mathematics, the researchers investigated the implications of the creation of particle pairs near black holes. Remarkably, the findings of the study revealed that the occurrence of new particles can extend far beyond the traditionally assumed boundaries of the event horizon.
Researcher Michael Wondrak says that their new work demonstrates that “in addition to the well-known Hawking radiation, there is also a new form of radiation.”
“We show that far beyond a black hole the curvature of spacetime plays a big role in creating radiation. The particles are already separated there by the tidal forces of the gravitational field,” adds Professor Walter van Suijlekom.
While earlier assumptions suggested that radiation could only occur within the confines of an event horizon, this research reveals that such a boundary is not indispensable.
“That means that objects without an event horizon, such as the remnants of dead stars and other large objects in the universe, also have this sort of radiation,” points out researcher Falcke.
“And, after a very long period, that would lead to everything in the universe eventually evaporating, just like black holes. This changes not only our understanding of Hawking radiation but also our view of the universe and its future.”
The study was published in the leading journal Physical Review Letters today.
Source: 10.48550/arXiv.2305.18521
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