One of Stephen Hawking’s most famous theories was proved by oscillations in space-time caused by the merging of two distant black holes.
Stephen Hawking proposed the theory of the area of a black hole in 1971 based on Einstein’s theory of general relativity. According to this theory, the surface area of a black hole can’t decrease over time. This law is closely related to the second law of thermodynamics; many physicists became interested in it. According to the second law of thermodynamics, the entropy or irregularity of a closed system is always increasing. The entropy of a black hole is proportional to its surface area; As a result, both should increase.
According to new research, proving the law of area can reveal significant clues to the secret laws that govern the world. The law of area seems to be at odds with Hawking’s other well-known and well-known theories: black holes evaporate over long periods of time; As a result, calculating the source of the contradiction between the two theories can reveal a new physics. According to Maximiliano Issy, lead author of the paper and astrophysicist at the Massachusetts Institute of Technology:
The surface area of the black hole does not decrease; This law is similar to the second law of thermodynamics. Also, according to the law of conservation of energy, the mass of a black hole is not reduced. This discovery can be very fundamental. Black holes have entropy, and this entropy is proportional to their area. This fit is not only attractive; Rather, it can reveal profound truths about the world.
The surface area of a black hole is determined by a boundary called the event horizon, beyond which there is nothing, not even light, and its strong gravity cannot be escaped. According to Hawking’s theory of general relativity, the area of a black hole does not decrease as the area of the black hole increases with mass, and since no object entering the black hole can leave it; But the surface area of the black hole decreases as it rotates further; As a result, researchers are questioning whether it is possible to throw an object into a black hole that is hard enough to make the black hole rotate enough to reduce its area. According to EC:
Even if you increase the spin, this rotation is not enough to balance the added mass. Whatever you do, mass and rotation increase the surface area.
To test this theory, the researchers analyzed the gravitational waves or oscillations in the texture of space-time that occurred 1.3 billion years ago when two massive black holes collided. The two black holes were moving toward each other at high speed. Gravitational waves were first detected in 2015 through the Gravitational Wave Observatory with Advanced Laser Interference (LIGO); A laser beam with a length of 3,000 km that can record the smallest deviations of space-time based on the change in path length.
Stephen Hawking’s famous theory of black holes proved
By dividing the signal into two parts, before and after merging the black holes, the researchers calculated the mass and rotation of the two main black holes and the combined black hole. This statistic allowed them to calculate the surface area of each black hole before and after the collision. According to EC:
As black holes rotate faster around each other, the amplitude of the gravitational waves increases; To the extent that the waves increase dramatically when black holes collide. The result of the new black hole is an aroused state in which the type of oscillation can be examined; Just like ringing a bell. Specific steps and duration of tones tell about the structure of the alarm and its composition.
Based on the evidence, the surface area of the new black hole was larger than the two original black holes. As a result, Hawking’s area law is proved with a 95% confidence interval. According to the researchers, the results are completely in line with expectations. The theory of general relativity plays an important role in describing black holes and other large objects in the sky; But the real secret becomes apparent when we try to reconcile the theory of general relativity (the law of large objects) with quantum mechanics (the law of very small objects). In this case, strange things will happen and the current rules without flexibility will be questioned.
According to the theory of general relativity, black holes cannot shrink; But based on quantum mechanics they can. Stephen Hawking developed a concept called Hawking radiation, according to which fog of particles is emitted through strange quantum artifacts at the edges of black holes. This phenomenon causes the black holes to shrink, and eventually the black holes will evaporate over longer periods of life. This evaporation will occur over very long periods of time and will not violate the law of area in the short term; But even this reason could not convince physicists. According to EC:
Statistically, the law of area is violated over a very long period of time. Just like boiling water. As water evaporates, steam rises from the vessel; But if you just look at the disappearance of water, it seems that the entropy of the vessel is decreasing; But if you also count the steam, the total entropy increases. The same is true of black holes and Hawking radiation.
Since the law of area is proposed for short to medium intervals, the researchers’ next step will be to analyze the data obtained from gravitational waves to gain deeper insights into black holes. According to EC:
I’m impressed by the high contrast of black holes. These objects are very complex and mysterious; But at the same time, they are the simplest objects in the world. These objects are where gravity and quantum mechanics collide; For this reason, black holes provide a good basis for understanding reality.