How do black holes affect entropy?
If black holes carried no entropy, it would be possible to violate the second law by throwing mass into the black hole. The increase of the entropy of the black hole more than compensates for the decrease of the entropy carried by the object that was swallowed.
Why do black holes have high entropy?
Because of the singularity of a black hole and the intense gravity, there is an extremely high amount of energy concentrated in one area. This means that, within the system, there is an extremely low amount of usable energy and therefore high entropy.
Do black holes increase or decrease entropy?
The black hole is similar. You can’t tell what type of matter fell in or when it collapsed. The second feature is that Hawking proved that the area of black holes is always non-decreasing. That reminds one of the thermodynamic second law, that entropy always increases.
Who discovered the entropy of a black hole?
Jacob Bekenstein
Almost 50 years ago, the late physicists Jacob Bekenstein and Stephen Hawking independently discovered that a black hole’s entropy is directly proportional to its surface area.
What is the Bekenstein Hawking formula?
An important black hole observable is the Bekenstein-Hawking (BH) entropy, which is proportional to the area of the event horizon, SBH = Ah/(4G).
Can a black hole get full?
It takes a shockingly long time for a black hole to shed all of its mass as energy via Hawking radiation. It would take 10100 years, or a googol, for a supermassive black hole to fully disappear.
Is Stephen Hawking wrong about black holes?
But the flawed analogy he put forth in his most famous book, A Brief History of Time, is not correct. Hawking radiation is not the emission of particles and antiparticles from the event horizon. Stephen Hawking knew how black holes truly decay, but he told the world a very different, even incorrect, story.
How is the entropy of a black hole determined?
Like the temperature equation, the equation for entropy contains both Plancks constant and the Gravitational constant, showing that black hole entropy is a strictly ‘quantum-gravitational’ effect. As a black hole radiates via this virtual particle method it will loose mass and get smaller.
How does the second law of thermodynamics apply to black holes?
The second law of thermodynamics requires that black holes have entropy. If black holes carried no entropy, it would be possible to violate the second law by throwing mass into the black hole. The increase of the entropy of the black hole more than compensates for the decrease of the entropy carried by the object that was swallowed.
What are the main equations for a black hole?
The main equations we have so far for a black hole are 3, 4 and 5. As you can see, the only variable in equations 3 and 4 is mass (). Equation 5 only depends on the surface are of the event horizon, however the surface area of a sphere depends on its radius, and from equation 3 we know that radius depends on.
What happens when matter flows into a black hole?
When matter entropy flows into a black hole, the GSL demands that the increase in black hole entropy shall more than compensate for the disappearance of ordinary entropy from sight. This has been verified by examples (Bekenstein 1973).