|Public space, social space, personal space, and intimate space diagram (showing radii in feet) based on American anthropologist Edward Hall’s 1966 global interpersonal measurements and theory of reaction bubbles.|
See main: Human systemThe concept of personal space is intuitive in the thermodynamical study of volumes in human systems. Studies show, for instance, that alpha males and alpha females are given more individual or personal space. A supermodel, someone who is generally considered physically "hot", when walking alone through a crowd of people will be given more personal space than as compared to a more homely female.  This phenomenon is connected to Boerhaave's law.
Moreover, when people are asked to approach a stranger and stop when they no longer feel comfortable, they will stop about two feet away from a tall person (22.7 inches to be exact) but less than a foot (9.8 inches) from a short person. As height is correlative with physical attractiveness, e.g. shorter than average men and women are less attractive than taller men and women, it is found, according to attractiveness researcher Nancy Etcoff, that: 
“Very attractive people of any size are given bigger personal space and territory; which they carry around with them.”
In other words, physically ‘hot’ molecules, in a sense, trigger volume increase be it a gaseous molecule or a human molecule. 
Sidewalk personal space study
See main: Sidewalk studyThe 1975 Sociometry article "Beauty is Power: the Use of Personal Space on the Sidewalk", presenting the results of the time lapse filming of pedestrians observed from above walking along a sidewalk, by American sociologists James Dabbs and Neil Stokes, seems to be the first quantified study of the relation between beauty and personal space volume increase. 
See main: Human chemistryThe logic and measurements of reactionary personal space regions is a key anchor point in the development and understanding of human chemical bonding, particularly on the topic of human molecular orbital theory, in which the stablizing overlap of hybrid orbitals functions to instill a bonding effect in the system, as is the case in standard molecular orbital theory. 
● Social piston and cylinder
● HCT | P4: Piston and cylinder view – Thims Apr 2013 lecture
1. Thims, Libb. (2007). Human Chemistry (Volume One), (pgs. 223-33, ch. 9: Human Molecular Orbital Theory, pgs. 247-95). (preview), (Google books). Morrisville, NC: LuLu.
2. Etcoff, Nancy. (1999). Survival of the Prettiest: the Science of Beauty. New York: Anchor Books.
3. Dabbs, James M. and Stokes, Neil A. (1975). “Beauty is Power: the Use of Space on the Sidewalk” (abs), Sociometry, 38: 551-57.
● Hartnett, J.J. Bailey, and Harley, C. (1974). “Body Height, Position, and Sex as Determinants of Personal Space” (abs), Journal of Psychology¸ 87:129-36.
● Thims, Libb. (2006). “High School Cafeteria Seating Distributions”, IoHT publications.
● Personal space – Wikipedia.