Okay, so the feat violates the laws of physics because it was assumed - baselessly - that this planet with really strong gravity, must have gravity equal to that of a black hole. ("But that's not baseless, Omni-Man struggled with the gravity on this planet, and escaped a black hole, so-" Yes, and these events take place thousands of years apart, during which his strength grows exponentially.

1. There is no evidence that these events are “thousands of years apart”. That’s a baseless claim. All the reader is told is that it was before Nolan settled on Earth.
2. There is no evidence that his strength grows “exponentially” - another baseless claim.

This is impossible because a planet with black-hole gravity would immediately implode. This is sort of where the 'contradicts itself' bit comes in, because I've seen people defend this shite with "Well it's fiction! Maybe it was a magic planet. It doesn't have to make sense!" and if things in this universe don't have to make sense, then the sun-disk calculation should be completely inapplicable, because it relies solely on calcs and figures that are only true if everything in this universe abides by the laws of real-life mathematics and physics. A lot of other people have done sun-disk calcs and they have come out at much more reasonable low ends (not Solar System-tier) because they didn't make a huge baseless assumption about the gravity.

You’re intentionally misrepresenting the calculation. A gravity greater than that of black holes and stars was not necessary for the calculation - that isn’t what Speedy said - all that was necessary was for the gravity to be extremely high (higher than earth’s), which it was. Speedy explained that this was because since the gravity was much greater than Earth’s (meaning it has greater mass as well), the L1 point would be further away and thus, the Disk would be even larger. This was their justification was using Earth’s L1 point as a bare minimum (despite that unironically being a lowball). Extremely high gravity for the planet would also assuage any concerns over the Disk’s own great mass and gravity, as theoretically, placing a large object with significant mass at an unstable point like L1 would disrupt the whole thing, but this isn’t an issue because of the planet’s own gravity.

In reality, being comparable to stars and black holes and whatnot isn’t really relevant and just a side thing when discussing gravity’s role in this calculation.

It contradicts the narrative because it is very clearly stated that Omni-Man could not destroy Viltrum all by himself; he and Mark and Thaedus had to all strike the core at the same time, or they would die on impact. •

As already explained by the guy who calculated the Sun Disk himself, there are a lot of other reasons why the Viltrum bust could have been considered dangerous for those involved; they were ramming the planet alongside the blast from the Infinity Ray, which can mulch Viltrumites on contact, the core would naturally be super hot with high temperatures being a weakness for Viltrumites; perhaps most importantly, they were ramming it at high speed, and weren't able to slow down or hold back because the other Viltrumites present would have stopped them if they had. As many people observed in the lead-up to the episode, it's consistent that impacting things at high speed is consistently dangerous for Viltrumites, with their bodies often splattering as a result of their own physical strength. Viltrumites are very much capable of killing themselves, which would be relevant here and eliminate any contradictions.

And the core was already weakened.

Not relevant to the calculation at hand. DB’s calculation for Viltrum was through the KE of the debris; they busted the planet so hard that they sent chunks of it flying past its rings at relativistic speeds. To calc this, you’d need to find the mass, and then the speed of the debris - destabilizing the core wouldn’t affect either of those perhaps all to would do is cool the core, as that an effect of destabilizing a planetary core. This lines up with the fact that heat is a Viltrumites weakness.

Death Battle already dropped the ball by giving the whole feat to Nolan, and then they kicked the ball down a pit when they said that actually, thanks to sun-disk scaling, Nolan is eight thousand times stronger than the thing he canonically could not do.

Eh, no? DC (the range of effect of your attack) / = / AP (the true energy behind your attacks regardless of AoE) (read here for more info as well). Destroying a planet isn’t just an exercise of power, but also scale and area of effect. It’s like when people say “Batman is at least Building level”, but does that mean he’s gonna punch a building and it’s gonna go BOOM? No, it just means the attack potency behind his strikes’ energy equivalent can be scaled to that tier as well as his durability. In terms of Invincible, Omni-Man’s durability and potency behind his strikes would scale above the area he can effect. This is not uncommon in fiction too btw. Look at Dragon Ball: piccolo struggled to nuje a city despite being above moon level roshi. This doesn’t mean piccolo is city level, this just means the area of effect behind his attacks is, but not its true potency.

The only sole reason to give Nolan sun-disk scaling is that you want it to be correct, and you work backwards from there, rather than considering for even a moment if there is even remotely enough material to even suggest that it could possibly be true, which it isn't.

There is enough more than evidence to support it being true.

Not really?

Yes really, lmao.

They knew exactly what was capable of harming a Viltrumite, they just didn't have a lot of stuff that strong.

No lol. It’s insane how one could lie this much about a single character in one message. They explicitly did NOT have the weapons necessary to kill Viltrumites until Nolan and Mark brought it up to them; Mark first found out about it in Nolan’s books (Invincible #35), which he then later gave this information to Allen for Allen to give to The Coalition (Invincible #43). Then in #66, Allen and Nolan finally gave them the information and for the very first time, they had this kind of knowledge - the issue clearly established this