Where does recombination collide?

In genetics, recombination is the reshuffling of alleles that occurs when paired chromosomes exchange segments during meiosis, so that offspring inherit combinations of genes that neither parent carried. Sturtevant's 1913 The linear arrangement of six sex-linked factors in Drosophila turned the frequency of this crossing over into the first genetic map, reasoning that genes farther apart on a chromosome are separated by recombination more often. The referent is a physical exchange of DNA between chromosomes that generates new genotypes, measured as a recombination frequency between loci. It has nothing to do with a charge carrier being annihilated in a semiconductor or an economy generating growth by mixing existing ideas.[1]

Unit

The recombination frequency between two loci, the fraction of offspring that are recombinant

Recovery means

Not applicable

Measured by

Estimated from the proportion of recombinant offspring in a cross, which maps to genetic distance in centimorgans

In semiconductor physics, recombination is the event in which a conduction electron falls back and annihilates a hole, removing a pair of mobile charge carriers and releasing the energy difference as light or heat. Shockley and Read's 1952 Statistics of the recombinations of holes and electrons gave the standard theory of how traps and defect levels govern the rate at which carriers recombine, a rate that sets the performance of transistors, solar cells, and light-emitting diodes. The referent is the disappearance of an electron-hole pair inside a solid, quantified by a recombination rate and carrier lifetime. It is unrelated to chromosomes exchanging segments or to the recombination of ideas in an economy.[2]

Unit

The recombination rate, or equivalently the minority-carrier lifetime before an electron-hole pair annihilates

Recovery means

Not applicable

Measured by

Inferred from carrier lifetime measurements and from the trap statistics that set the recombination rate

In the economics of innovation, recombination is the idea that new knowledge is produced mainly by combining pieces of existing knowledge, so the stock of possible innovations grows combinatorially as the base of components expands. Weitzman's 1998 Recombinant growth formalised this by modelling ideas as configurations of prior ideas, showing that the number of potential new combinations can explode while the human capacity to process and test them becomes the binding constraint on growth. The referent is the generation of economic novelty by mixing existing components, tracked through the growth of the idea set and the bottleneck of processing capacity. It shares only the word with chromosomal crossing over or the annihilation of charge carriers.[3]

Unit

The set of new ideas formed as combinations of existing ideas

Recovery means

Not applicable

Measured by

Modelled as the combinatorial growth of possible idea configurations against the limited capacity to develop them