A body with Earth-like density and this radius would gravitationally compress itself enormously. Realistically, it would collapse toward stellar structure physics. You cannot keep ordinary rocky-planet density at this scale without exotic matter or fictional stabilization. One Piece makes no particular effort to make the soil, gravity, or scale of the planet that big, the fact you got that result from an Earthquake is also telling, it might be just a case of genuine ignorance on Oda's part.
Logically, this size makes no sense given the whole worldbulding, and the same physics you're using. 10km deep water and 10km high clouds on a 3 million km radius is
functionally insane.
Also, you made an
objective mistake on GBE.
Why did you use the
km unit instead of the
meters?
The value you should be using is: R =
3628800000m
Pluging that denominator we have:
GBE: (3/5) * 6.674e-11 * (1.1038834563235711e+33)^2 / (3628800000) = 1.34468596e46Joules or
134.4685 Foe
So the calc overshoots by exactly 1000× due to unit mismatch.
Also, another issue, you claim "
everyone felt the Earthquake at the same time 6 days later", this is
nonsense,
completely irrealistic, thus, a center-reflection propagation model is speculative. Real seismic waves do refract through planetary interiors and emerge globally, but not in a perfectly synchronized fashion. The manga likely ignores travel timing entirely for narrative simplicity. That's not how Earthquakes work whatsoever. The phenomenon itself is just as realistic as the planet size it provides.
Also, the propragation speed assumes immense internal pressure without accouting for the consequences of having such internal pressure in the first place.
One more problem, even if we grant the perfect synchronization, the 6-days don't necessarily represent seismic travel time. Because waves from
one island don't converge on the
geometric center of the planet, they travel outward in all directions and would converge near the antipodal point of Lulusia. A true omnidirectional rebound from the core requires the energy to arrive at the core from
all directions at once, which requires the explosion to be occurring everywhere on the planet simultaneously, not just at one island.
For everyone else, let me
explain exactly what the calc assumes to be happening:
- Lulusia explodes.
- Seismic energy travels inward.
- The waves reach the planet’s center.
- The center acts like a perfect redistribution point.
- The energy rebounds outward equally in all directions.
- The entire planet feels the quake simultaneously.
You don't need me to explain that this does not work under any physics model to ever exist, right? You don't get to use a realistic formula for an unrealistic feat.
Seismic wave propagation from a localized source does not behave like this geometrically. A single-point explosion does not produce a synchronized spherical collapse into the center. If you explode one island on a sphere, the wavefront expands outward from that point.
Seismic energy from a point source doesn't behave like a balloon inflating from the center of the planet outward. It behaves like a ripple in a pond, radiating outward spherically in all directions from that one point of origin. The wave front is not centered on the planet's core. It is centered on Lulusia.
Because of this, the wave front expands asymmetrically relative to the rest of the planet. Locations near Lulusia feel the shaking first. Locations far from Lulusia feel it much later. Locations on the opposite side of the planet feel it last. This is seismology's most basic rule about point-source events and there is no configuration of a single surface explosion that breaks it.
"Well, but they all DID feel it at the same time!"
Doesn't matter. That in itself is unrealistic, meaning the feat is unrealistic, thus the assumption it makes is also unrealistic.
The calc's model requires the energy to hit the planet's core and then rebound outward in all directions simultaneously, like an explosion at the center of the sphere. This is the only geometry that would produce perfectly simultaneous surface arrival everywhere at once. But for that to happen, the energy would need to arrive at the core from all directions at the same time. Think about what that requires: every point on the planet's surface would need to be generating seismic energy inward simultaneously, all converging on the core at the same moment. That is the only input geometry that produces an omnidirectional rebound output. A single surface explosion at Lulusia does the opposite, it sends a single wave front that arrives at the core from one direction, at one moment, and continues propagating outward in a lopsided, asymmetric pattern. What you get from a one-sided impact on the core is not a uniform sphere of energy expanding outward. You get continued directional propagation, with some refraction and scattering. Not a simultaneous global pulse.
I'm sorry, but this is a disaster. I don't have any authority, but I did want to give my two cents.
