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Alright so this exists for the purpose of pointing out a double-standard in the rules for Kinetic Energy feats.
So, Faster Than Light Kinetic Energy is not allowed given how the Relativistic KE Formula goes to infinity energy at light speed, and using the Regular Kinetic Energy Formula which ignores relativistic mass isn't allowed because that's not how you [physics].
Despite this, calculating Gravitational Binding Energy for celestial bodies which, by all natural laws should absolutely be Black Holes (Solar System sized planets and the like), is allowed. This is a double standard.
Now, why is this a double standard? Because the formula for Gravitational Binding Energy is based on the formula for Regular Kinetic Energy, plus 3 layers of trench-coats for the variables.
The simplified Gravitational Binding Energy Formula is based on having a uniform sphere, and "imagining that it is pulled apart by successively moving spherical shells to infinity, the outermost first, and finding the total energy needed for that." The energy to pull apart the spherical shell from the gravitational body is the negative of the Gravitational Potential Energy.
Gravitational Potential Energy (acceleration * mass * height) is just Kinetic Energy you'd have when hitting the ground from a certain height.
In other words, Gravitational Binding Energy is just the kinetic energy required to send apart the mass of a body fast enough that it won't come back together again. This can best be seen with how GBE can be roughly approximated by multiplying a celestial body's Mass by its surface Escape Velocity.
Not a perfect estimate of GBE, but still consistently within a factor of 2.
So when a body is so massive that it should become a Black Hole, it means that its surface escape velocity has exceeded the speed of light. Which means that it should be impossible to blast it apart due to Relativity- even if the celestial body still retained its shape and didn't collapse into a singularity somehow, the mass still has to move faster than light in order for the Celestial Body to be destroyed.
Impossibly Massive Celestial Body Calcs are basically doing the equivalent of using the Regular Kinetic Energy formula for FTL Speeds. Such as the calc of Godzilla Earth shattering Black Holes, Ergenverse's destruction of a Cultivator Planet, this Sage Monarch Calc, or (sigh...) the Asura's Wrath Moon Calc. (I'm so sorry Zamasu_Chan...)
As proof- I'm going to do the same GBE vs. Mass * Escape Velocity KE comparison for the Giga-Moon Calc-
TLDR: Here is the problem.
1. Planet/Star GBE is essentially the Kinetic Energy of its Mass times its Escape Velocity, plus a couple other factors
2. Black Holes are created when a star core is so crushed, that its escape velocity exceeds the Speed of Light
3. Impossibly Massive Celestial Bodies in fiction have Escape Velocities waaaay higher than Lightspeed, and should be Black Holes
4. Energy yields via FTL KE by using the regular KE formula isn't allowed, yet [Should Be A Black Hole By IRL Physics] Celestial Body GBE is usable for energy yield, despite the two being the same thing
5. That is a Double Standard.
Either we allow FTL KE, or we don't allow Impossibly Massive Celestial Body GBE.
(If you wanna know if a fictional planet/star should be a blackhole, just plug its mass and diameter into a Schwarzschild radius calculator. If the Schwarzschild radius is smaller than the Planet's radius, then it's not a black hole)
So, Faster Than Light Kinetic Energy is not allowed given how the Relativistic KE Formula goes to infinity energy at light speed, and using the Regular Kinetic Energy Formula which ignores relativistic mass isn't allowed because that's not how you [physics].
Despite this, calculating Gravitational Binding Energy for celestial bodies which, by all natural laws should absolutely be Black Holes (Solar System sized planets and the like), is allowed. This is a double standard.
Now, why is this a double standard? Because the formula for Gravitational Binding Energy is based on the formula for Regular Kinetic Energy, plus 3 layers of trench-coats for the variables.
The simplified Gravitational Binding Energy Formula is based on having a uniform sphere, and "imagining that it is pulled apart by successively moving spherical shells to infinity, the outermost first, and finding the total energy needed for that." The energy to pull apart the spherical shell from the gravitational body is the negative of the Gravitational Potential Energy.
Gravitational Potential Energy (acceleration * mass * height) is just Kinetic Energy you'd have when hitting the ground from a certain height.
Let's say a 1 kg object falls from a height of 10 meters, and experiences 9.8m/s^2 of acceleration.
Energy Via GPE (height*mass*acceleration)- 1 * 10 * 9.8 = 98 joules
Energy Via Kinetic Energy right before you hit the ground- Displacement = initial velocity*time + 0.5*acceleration*time^2
The ball is 10 meters off the ground, is unmoving before it falls, and falls at 9.8m/s2 so-
10 = 0*time + 0.5*9.8*time^2
10 = 4.9*time^2
sqrt(10/4.9) = time, time = 1.428571429 seconds
Accelerating 9.8 meters per second every second, after falling for 1.428571429 seconds, means the speed before hitting the ground is 9.8*1.428571429 = 14 meters per second
Kinetic Energy = 0.5*mass*velocity^2, so 0.5*1 kg*14 m/s^2 = 98 joules
Energy Via GPE (height*mass*acceleration)- 1 * 10 * 9.8 = 98 joules
Energy Via Kinetic Energy right before you hit the ground- Displacement = initial velocity*time + 0.5*acceleration*time^2
The ball is 10 meters off the ground, is unmoving before it falls, and falls at 9.8m/s2 so-
10 = 0*time + 0.5*9.8*time^2
10 = 4.9*time^2
sqrt(10/4.9) = time, time = 1.428571429 seconds
Accelerating 9.8 meters per second every second, after falling for 1.428571429 seconds, means the speed before hitting the ground is 9.8*1.428571429 = 14 meters per second
Kinetic Energy = 0.5*mass*velocity^2, so 0.5*1 kg*14 m/s^2 = 98 joules
Earth GBE: ~2.487*10^32 joules (from AP Chart)
Earth Mass * Escape Velocity KE: 0.5* 5.9722*10^24 kg * 11186m/s^2 = ~3.7364*10^32 joules
Difference: 2.487*10^32 vs. 3.7364*10^32 joules
Jupiter GBE: ~1.775*10^36 joules
Jupiter Mass * Escape Velocity KE: 1.898 * 10^27 kg * 60200m/s^2 = ~3.439*10^36 joules
Difference: 1.775*10^36 vs. 3.439*10^36 joules
Sun GBE: ~5.693*10^41 joules (from AP Chart)
Sun Mass * Escape Velocity KE: 0.5 * 1.98847*10^30 kg * 617500m/s^2 = 3.791*10^41 joules
Difference: 5.693*10^41 vs. 3.791*10^41 joules
Earth Mass * Escape Velocity KE: 0.5* 5.9722*10^24 kg * 11186m/s^2 = ~3.7364*10^32 joules
Difference: 2.487*10^32 vs. 3.7364*10^32 joules
Jupiter GBE: ~1.775*10^36 joules
Jupiter Mass * Escape Velocity KE: 1.898 * 10^27 kg * 60200m/s^2 = ~3.439*10^36 joules
Difference: 1.775*10^36 vs. 3.439*10^36 joules
Sun GBE: ~5.693*10^41 joules (from AP Chart)
Sun Mass * Escape Velocity KE: 0.5 * 1.98847*10^30 kg * 617500m/s^2 = 3.791*10^41 joules
Difference: 5.693*10^41 vs. 3.791*10^41 joules
So when a body is so massive that it should become a Black Hole, it means that its surface escape velocity has exceeded the speed of light. Which means that it should be impossible to blast it apart due to Relativity- even if the celestial body still retained its shape and didn't collapse into a singularity somehow, the mass still has to move faster than light in order for the Celestial Body to be destroyed.
Impossibly Massive Celestial Body Calcs are basically doing the equivalent of using the Regular Kinetic Energy formula for FTL Speeds. Such as the calc of Godzilla Earth shattering Black Holes, Ergenverse's destruction of a Cultivator Planet, this Sage Monarch Calc, or (sigh...) the Asura's Wrath Moon Calc. (I'm so sorry Zamasu_Chan...)
As proof- I'm going to do the same GBE vs. Mass * Escape Velocity KE comparison for the Giga-Moon Calc-
- Galaxy Sized Moon GBE: 1.9811372*10^93 joules
- Mass * Escape Velocity KE, with the Moon's Escape Velocity gotten from plugging the Radius and Mass into this Escape Velocity calculator- 0.5 * 2.4396811*10^61 kg * 16452333899637669m/s^2 = 3.30185575*10^93 joules
- 1.9811372*10^93 vs. 3.30185575*10^93 joules (BASICALLY THE SAME ENERGY VALUE, STILL WITHIN A FACTOR OF 2)
TLDR: Here is the problem.
1. Planet/Star GBE is essentially the Kinetic Energy of its Mass times its Escape Velocity, plus a couple other factors
2. Black Holes are created when a star core is so crushed, that its escape velocity exceeds the Speed of Light
3. Impossibly Massive Celestial Bodies in fiction have Escape Velocities waaaay higher than Lightspeed, and should be Black Holes
4. Energy yields via FTL KE by using the regular KE formula isn't allowed, yet [Should Be A Black Hole By IRL Physics] Celestial Body GBE is usable for energy yield, despite the two being the same thing
5. That is a Double Standard.
Either we allow FTL KE, or we don't allow Impossibly Massive Celestial Body GBE.
(If you wanna know if a fictional planet/star should be a blackhole, just plug its mass and diameter into a Schwarzschild radius calculator. If the Schwarzschild radius is smaller than the Planet's radius, then it's not a black hole)
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