Is mass an emergent property?

[Magical Realist]

If there is no such thing as matter, as some irreducible substance, which is basically what physics has shown all the way down to quarks, what becomes of mass and from whence does it arise?

Imagine a rock. It has mass and weight and inertia. Nobody would argue with that. Now imagine all the molecules in the rock being separated from each other by a very tiny distance. The rock would basically become something more like a brown cloud of molecules. The mass and weight and inertia it formally had would all be gone, and it would float away. What happened to the mass? And why does it appear to depend totally on whether the molecules are close enough to each to become a solid rock? Mass perhaps a property emerging from the compactness of the molecules and not inherent to matter itself?

[confused2]

From AI..

Only about 2% of the mass in an atom comes from the Higgs field coupling (intrinsic mass of quarks/electrons), while the remaining ~98% is the confined energy of gluon fields and quark movement.

So.. atoms are 'heavy' .. the energy binding them together to form molecules is small compared the amount an atom already 'contains'. So rock vapour weighs pretty much the same as rock.

Personally I have no idea what mass actually is beyond the equations it turns up in .. mainly Newton's Force=mass*acceleration and Einstein's E=mc^2.

[Magical Realist]

From AI..

Only about 2% of the mass in an atom comes from the Higgs field coupling (intrinsic mass of quarks/electrons), while the remaining ~98% is the confined energy of gluon fields and quark movement.

So.. atoms are 'heavy' .. the energy binding them together to form molecules is small compared the amount an atom already 'contains'. So rock vapour weighs pretty much the same as rock.

Personally I have no idea what mass actually is beyond the equations it turns up in .. mainly Newton's Force=mass*acceleration and Einstein's E=mc^2.

Science defines mass as the amount of matter in something. And it defines matter as anything that has mass. It's pretty circular.

I have a hard though believing the cloud of molecules would be heavy at all. You do know what a cloud is? Have you ever seen a cloud of dust? Or a cloud of water droplets? These aren't even made of separate molecules but much larger particles and yet they float away.

[Syne]

Mass can be defined as inertia, how difficult it is to start or stop an object's motion. This is the sum of all the constituent particle energies and their kinetic and potential interactions. Cloud and dust molecules are very sparse and relatively slow, where subatomic particles are very densely packed and very active, contributing more kinetic energy to the mass/energy equivalence.

[Magical Realist]

But the rock cloud wouldn't have hardly any of the inertia the solid rock did. And yet it has the same amount of molecules as the solid rock did. If not mass then where does inertia come from, and where does it go?

[Syne]

But the rock cloud wouldn't have hardly any of the inertia the solid rock did. And yet it has the same amount of molecules as the solid rock did. If not mass then where does inertia come from, and where does it go?

This is because density (stuff per volume) is directly related to inertia.

Turning the solid rock into a cloud of dust means that you've reduced the density. In effect, you've scattered the mass so that there's now space to push molecules individually (with enough space or freedom of motion, the interaction inertia from them colliding is negligible). So you can basically push an individual molecule at a time, where a solid rock requires pushing every molecule at once.