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the soft gluon radiation from single hard scatterings, BDMPS examined the multiple soft scattering limit, similar to Migdal and Moli` ere scattering [293– 295]. Contemporaneous to the BDMPS papers, Zakharov developed his own formalism employing path integration [261–264], later shown to be equivalent to the BDMPS approach [256]. 

The thin plasma limit of GW was extended in the opacity expansion work of Gyulassy, Levai, and Vitev [271–274]. The reaction operator approach they developed allowed the derivation of a closed form solution of the resummed single inclusive gluon radiation distribution dN$_{g}$/dxd $^{2}$k to all orders in opacity, χ = L/λ . At a similar time, Wiedemann examined the dipole path integral, opacity expansion, and the Zakharov and BDMPS limits [266–268]. He and Salgado [269] numerically investigated the BDMPS and GLV results, pub- lishing a popular public code for calculating BDMPS energy loss ‘quenching weights.’ 

In QED the infrared divergences from single scattering bremsstrahlung exponentiate into a Poisson distribution of multiphoton fluctuations about the semiclassical expectation value [251]. Multigluon fluctuations were in- corporated in [275] by assuming this Poisson form: P ( ϵ | p$_{T}$ ) = $^{∑}$$_{n}$P$_{n}$ ( ϵ | p$_{T}$ ), P$_{1}$ ( x | p$_{T}$ ) = exp( −〈 N$_{g}$ ( p$_{T}$ ) 〉 ) dN$_{g}$/dx ( x ; p$_{T}$ ), and 

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where the final momentum is expressed in terms of the initial momentum as 

