# Would an anti-gravity organ allow kaiju to avoid cube-square problems?

It is (around here, anyway) quite well known that science does not allow the existence of kaiju, mainly because of the cube-square law. bones rip themselves out To my understanding, this boils down to "If it is twice as high, it is eight times as heavy, but its legs can only support four times the weight." (I assume that it's the cross-section that gives support strength, anyway). There are also problems with distances nerve signals need to travel, but that is out of the scope of the current question.

My question is this: suppose a kaiju's bones have anti-gravity capabilities, resulting in the bones specifically having negative effective weight (Not mass), while keeping the rest of a normal bone's properties, such as strength. Would this allow kaiju to exist? Or would the weight reduction needed make the bones rip themselves out of the poor creature's body, flying into the air (Basically, the body can't keep the bones in place)?

• As this would reduce the weight of the entire kaiju, it would explain how other kaiju and our own jaegers can literally throw each other across town when brawling – Kyyshak Feb 5 at 11:02
• Once you have anti-gravity, you have infinite energy generation. There is no other possibility unless you throw out all of classical as well as quantum physics. – Carl Witthoft Feb 5 at 16:26

Imagine a steel beam on a house. It's rigidly held in place (for all intents and purposes it defies gravity).

Now try building out from that steel beam using nothing but bacon. Sooner or later you will reach a point where the bacon starts to droop and sag and 'flow' off the beam. Even if you try to build your bacon floor out towards the centre of a square of these beams it will sag downwards. You can fix this by either not building out so far or by adding more steel beams.

So your 'antigravity' bones must either be spread throughout the structure of the kaiju or your kaiju needs to be really, really thin (including chest cavities etc).

This also doesn't account for the strength of the bones or the amount of force needed to actually move. Antigravity does not stop inertia, so your kaiju will have to move really slowly or risk dying when it tries to turn too sharply.

So all in all: Antigravity bones might not work too well. Antigravity blood plasma, on the other hand...

• Good answer! Changing it to blood plasma actually ties in rather well to some worldbuilding I have already done. – Mark Gardner Feb 5 at 13:25

Bones are fine, but..

Bones account for about 12% of the weight of the human body, and assuming the same would apply to a Kaiju (Which it doesn't have to), for the purposes of weight, it seems like they wouldn't have to generate that much negative weight.

A 100t Kaiju, with bones that are in direct -1g, would have bones that are minus 12 tonnes, meaning it would only weight 76 tonnes (Remember, the bones remove 12 tonnes, but their own weight is also removed, which is 12 tonnes on their own) So that's already 1/4 less weight. Upping it to 20%, and you get 60t, less then 2/3 of the original.

So for the strict purpose of reducing weight, this would work, but bones aren't the only thing keeping a big organism alive

For instance, blood has weight too, and with the 8 fold increase in mass, comes an 8 fold increase in the volume of blood, which has to be handled by the heart.

I'm not sure about the mechanics of a heart suddenly handling all that, mostly because I think just as with the cross section you mentioned of the bones, the heart while 8 times the mass, can only handle 4 times the blood. Same with air.

..Maybe something else?

But maybe if the bones, or some other organ, generate negative mass in connected tissue? Mass Effect fields, from Mass Effect, was essentially generated by Element Zero being given an electric current, and the configuration determined the strength, allowing negative mass, and thereby FTL travel.

But they didn't just use it for FTL travel. Engineering of buildings and spaceships also relied on it. A spaceship weighing half it's weight, would be twice as maneuverable with the same amount of maneuvering thrusters.

Effective control of such an organ, (like a muscle), could allow the Kaiju to increase it's mass when defending or attacking, or decrease, for increased mobility.

And most importantly, it would affect the weight of muscles, including heart and lungs, so that maybe, they have a fighting chance of moving all that air and blood around, now that they have to deal with less weight, and their own muscles can spend more energy on moving air or blood around when they don't have to support themselves quite as much.

Edit: As pointed out by Joe, lessened or negative gravity on blood or air would also work against the system.

• Reduction in force due to gravity is not reduction in mass. The heart will have to work just as hard to pump antigravity blood because the reduction in work to push blood up the body is matched by an increase in work needed to push it down, plus the blood still has the same mass that needs pushing in the first place. Dammit physics. – Joe Bloggs Feb 5 at 11:52
• @JoeBloggs The equilibrium was not something I had considered, but I still think there is a net positive to gain here. It just might not be enough to justify a Kaiju now, I think. – MartinArrJay Feb 5 at 11:59

No, because the square-cube problem also affects things like lung capacity. They only have a fraction of the lung surface area they need to get enough oxygen. Similarly, problems with overheating.

Bones ripping out of our favorite big lizard shouldn't be a problem. So long they are not much more on negative weight then would be on positive. Creatures are already well designed to hold to its bones, it would be not much difference if bones are puling up with negative gravity or down with normal.