Where does repulsion collide?

Charles-Augustin de Coulomb established in 1785 (Premier mémoire sur l'électricité et le magnétisme) that two bodies carrying the same kind of electric charge push each other apart with a force that grows with the size of the charges and falls off with the square of the distance between them, the same inverse-square law governing like magnetic poles. A distinct short-range repulsion between atoms, arising from quantum effects rather than from Coulomb's law, keeps matter from collapsing into itself. Here repulsion is a physical force measured in newtons that acts between charged or magnetised bodies, not a tendency to avoid a dissimilar person or an arrangement of alleles on a chromosome.[1]

Unit

A force between like charges or like poles, in newtons

Recovery means

Not applicable

Measured by

Calculated from Coulomb's inverse-square law and measured with a torsion balance or a force sensor

William Bateson and Reginald Punnett used the term in 1911 (On gametic series involving reduplication of certain terms) for the situation in which two particular hereditary factors tend to be inherited apart rather than together. Thomas Hunt Morgan's 1911 work recast coupling and repulsion as consequences of the physical position of genes on chromosomes: factors are in repulsion, later called the trans phase, when their alleles sit on opposite members of a homologous pair. Here repulsion names a spatial arrangement of two alleles across paired chromosomes, not a force between charges or an aversion between people.[2][3]

Unit

A phase of two alleles: repulsion (trans) when on opposite homologs

Recovery means

Not applicable

Measured by

Inferred from the frequencies of offspring types in a genetic cross and expressed as a recombination fraction

Milton Rosenbaum proposed the repulsion hypothesis in 1986 (The repulsion hypothesis: On the nondevelopment of relationships), arguing that the well-documented link between attitude similarity and attraction owes less to similarity drawing people together than to dissimilarity driving them apart. On this account people first screen out those whose attitudes clash and feel attraction toward the rest, so avoidance of the dissimilar, rather than attraction to the similar, does most of the work. Here repulsion is a tendency to dislike and avoid dissimilar others, measured by ratings of liking, not a physical force or a chromosomal arrangement.[4]

Unit

A person's tendency to avoid dissimilar others, on a rating scale

Recovery means

Not applicable

Measured by

Assessed by attraction or liking ratings toward others of varying attitude similarity