Is Black Hole Gravity Strong Enough to Crush Earth into a Watermelon?

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SUMMARY

The discussion centers on the strength of black hole gravity and its implications for Earth. Participants assert that black holes form when massive stars collapse under their own gravity after exhausting nuclear fusion, leading to extreme density. Key points include the distinction between black holes and other massive objects, emphasizing that a black hole's gravitational influence is solely dependent on its mass. The conversation also clarifies that Earth's gravity is insufficient to compress it to a size comparable to a watermelon due to its lower mass and density compared to black holes.

PREREQUISITES
  • Understanding of black hole formation and stellar evolution.
  • Knowledge of nuclear fusion processes and their role in stellar life cycles.
  • Familiarity with concepts of mass, density, and gravity.
  • Basic grasp of astrophysics and gravitational theory.
NEXT STEPS
  • Research the process of stellar collapse and black hole formation.
  • Study the role of nickel in stellar fusion and its implications for density.
  • Explore gravitational theories and their mathematical foundations related to black holes.
  • Investigate the effects of black holes on surrounding celestial bodies and the solar system.
USEFUL FOR

Astronomy enthusiasts, astrophysicists, and students studying stellar dynamics and black hole physics will benefit from this discussion.

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when massive stars run out of fuel for nuclear fusion it loses the electromagnetic outward force to negate the inward pull of gravity so gravity gets an upperhand over outward force and thus gravity jampack the rest of matter so tightly that one spoon of Blakhole matter (nuclear fusion residue) weighs 5 tons

if this is the theory of formation of black hole gravity must be very strong in order to cram tons of matter of former sun to the size of a planet and I'm wondering what stops Earth's gravity to squish our planet to the size of watermelon

if gravity is solely depend on mass i think people like hawking and prof kaku are exaggerating power of black hole ,i think a black hole would be just be a half shredded compact sphere of matter composed of nuclear fission residue ,it can't gulp anything more MASSive than its mass
 
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3112100000 said:
when massive stars run out of fuel for nuclear fusion it loses the electromagnetic outward force to negate the inward pull of gravity so gravity gets an upperhand over outward force and thus gravity jampack the rest of matter so tightly that one spoon of Blakhole matter (nuclear fusion residue) weighs 5 tons

The outward pressure is due to kinetic energy of the particles in the plasma, not just the EM force. Also, there is no such thing as "Blackhole Matter", as it is unknown what happens to matter that is inside the event horizon of a black hole.

if this is the theory of formation of black hole gravity must be very strong in order to cram tons of matter of former sun to the size of a planet and I'm wondering what stops Earth's gravity to squish our planet to the size of watermelon

Simple. We aren't massive enough. The key to a black hole is DENSITY. Massive stars have their cores collapse into black holes and neutron stars because the final stage of fusion builds up Nickel. Since fusing nickel with itself requires energy instead of releasing it, you have a buildup of a huge amount of dense material that isn't generating energy anymore. At a certain point the nickel builds up to such huge amounts that it's gravity is simply too much and it collapses into a black hole or neutron star and generates a massive supernova. The important thing is that the density of the core increased after it produced nickel, as it cannot replace the energy released after being compressed into a smaller volume by gravity. This is the key to fusion inside stars. Initially they are powered and heated up by gravity. It is only after they have collapsed enough to heat their cores up to very high temperatures that fusion starts to happen. Once this occurs the rate of fusion reactions counterbalances gravity. If the fusion rate slows down then gravity compresses the star slightly which then causes the rate of fusion to increase to counter it again.

if gravity is solely depend on mass i think people like hawking and prof kaku are exaggerating power of black hole ,i think a black hole would be just be a half shredded compact sphere of matter composed of nuclear fission residue ,it can't gulp anything more MASSive than its mass

This is not how a black hole works. There is no difference between a black hole and any other object other than the amount of mass. If you were to replace the Sun with an equal mass black hole nothing in the Solar System would notice. Well, other than that pesky lack of sunlight. But in regards to the gravitational field it would be the same. It is only when you get closer to the black hole that it changes.
 
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There are volumes of math that assert [and constrain] the compactification of matter required to form a black hole.
 

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