Does the space between molecules have no pressure?

Question

In any living organism there exists are space between cells filled with interstitial fluid. Loss of this fluid into abnormal areas (3rd spacing) can cause relative to severe hypo-volemia. The fluid holds the cells in place and acts as a buffer.

Picture a bowl full of clear glass marbles. Fill it with clear liquid. Slowly drain the fluid out. The marbles cannot contort to fill in the gaps. If the system were closed and the water pumped out, a tremendous, Incompressible, vacuum would occur.

Living cells, on the other hand, CAN disfigure. Of course, this causes, depending upon the amount if distortion, cellular function disruption. In the case if someone losing interstitial fluid as a result if external trauma, the O2 sat levels will fall, leading to an initial decrease in the level of consciousness. Unabated loss will end in death.

What if the obvious space between molecules? Cells are, after all, just that. Living carbon-based masses of molecules. Remove the carbon, glucagon, and you have no life.

I submit that there must exist a 0 pressure 'dead-space' between molecules. Arguments?

Answer 1

Yes and no. "Pressure" is a macroscopic, emergent phenomenon: it arises through the large-number statistically averaging of the interactions between a macroscopic body and the particles of any fluid around it: the averaging gives rise to a seemingly constant force per unit area, which when examined microscopically comprises many, nonsteady, dynamic collisions. When you get down to talking about space between molecules, "pressure" is not really meaningful.

Also, the idea of "dead space" is a little misleading. "Empty space" or "Dead space" is nothing more than what you have when the ground state (vacuum state) prevails for all the (handful of) quantum fields making up the World. There is no such thing as a "void", aside from in the sense of my first sentence. This handful of quantum fields is what modern physics takes to be reality there is nothing else besides them. "Particles" and "molecules" are made up raised, non-vacuum states of the quantum fields. To get a basic idea of this, see the Wikipedia page on Quantization of the Electromagnetic Field: the "particles" (photons in this case) are the discrete energy packet "communications" between the quantized EM field and the other quantized fields (I like to think of particles as being more like data packets on the internet than billiard balls). We represent the quantum EM field as a set of quantum harmonic oscillators, one for each plane wave mode of Maxwell's equations. Through the Fourier transform, we can equally well think of this set as a set of QHO's, one for each point in space. Space is "empty" at the points whose QHOs are in their ground state for all the quantum fields. Empty space is made of ground state QHOs.