Too much of a good thing: endogenous business cycles generated by bounded technological progress

Following Jones and Williams (2000), we assume that R&D is simultaneously subject to positive and to negative external effects (e.g., the non rival nature of technology conflicts with congestion externalities). This observation allows to conceive an economy where two R&D sectors evolve without departing significantly from each other in terms of their productive results (society tends to penalize imbalances in technical progress, making negative external effects to appear associated to a sector when this outstands relatively to the other sector; the second sector, in turn, will be subject to positive externalities that reflect a catching up effect). The proposed framework, when associated to a growth setup, is able to replicate the existence of endogenous fluctuations and, therefore, it intends to be a contribution to the literature on endogenous business cycles.