You said:
.....and neither does density alone without taking into account comparable volumes
Your not getting it Sam, or I am not explaining it well enough. Density does take into account volumes because density is the direct relationship between mass and VOLUME. Density is computed by diving the mass of an object by its volume. So yes, density alone is what affects bouyancy.
Secondly, weight and bouyancy are not comparable units. Again, weight alone has nothing to do with bouyancy. Mass and weight are two seperate things, weight is a force, mass is not. Weight has no affect on density and therefore has no affect on bouyancy and bouyancy is what allows something to float.
Thirdly, hulled objects such as ships have extremely dense materials that they are comprised of, but the ship isnt the only thing displacing the water. The air within the ship does not have to be confined, you could simply have the nothing but a hull and it would still float. The air within the hull is also displacing the water because it is occupying the space that the water would otherwise be. So calculating the density of the ship isnt simply done using the volume of the materails it is comprised of, but by considering the entire ship, the air within the ship, including the air that is not confined or inclosed, as one singular unit. When combining the density of the ships materials, the density of the air and all components within the ship that displace where the water would normally be, you get a much lower density. Now to further expand on that notion, lets stretch that ship out an extra 20 meters in length while maintaining the same hull depth, mass of materials, and width of the hull (Basically just thinning the walls while stratching it). By doing so, you have kept the same mass but the density has drastically lessened The volume of manufactured materials is the same, the density of the materials is the same, but the combined density of the materials and air displacing the water create a more bouyant ship. Again, mass has stayed the same but the density has decreased substantially allowing the ship to float more readily, without ever changing the mass. When combining this with gravity, we get the "weight" that you refer too, but the "weight" is still unchanged as well. The ship became more bouyant without a change in weight, proving that weight alone does not affect bouyancy unless the gravitational constant changes for some reason.
Regardless, worms are not hollow or hulled and therefore none of that information is relevant to the issue at hand. Simple fact is, density is the only determining factor in bouyancy with all other environmental aspects being static, and the density is comprised of a relationship between volume and mass, not weight.
You said:
"Again, that pesky unit volume and for this discussion, volume, shape and zero air content leaves
weight as the deciding factor of what and how lures fall faster in water (the original topic)."
Incorrect again, as mentioned above, weight is not a deciding factor in bouyancy, mass and volume are. Weight is a force that can be given in multiple terms such as kgm/s^2, or slugft/s^2. Unlike the force called weight, density is given in terms of a mass and a volume only(kg/ml or however you want to assess it) without any restraints from time. If you were to use "weight" in your calculations for bouyancy, you would still have to divide by your gravitational constant to negate time and distance but even then you are only left with mass which doesnt equate to bouyancy without volume.
The difference in materials (not color) is what causes differences in density for glitter. Again, different glitters are made of different materials and therefore have different densities ranging from 1.2-2.5.
You have read what you have wanted to from my posts but I dont believe you quite understood, or maybe cared to understand, what I was saying. Maybe I didnt explainit well enough whichis my fault. Your use of the term "weight" in reference to bouyancy and density is misplaced and I don't think that you have realized that yet, or I may have been misreading all along.
Your absolutely right about the scientific method. Results obtained through the SM must first and foremost be repeatable under indentical circumstances and be similar to those first tested. I think you might be going a little bit on opinion while being under the impression that it is fact. However, you are right in that this is a fishing forum and we have gone way off topic. I apologize to everybody, including you SENKOSAM, and hope that we can move on to the OP. If you wish to discuss more, please feel free to PM me.