The standard model of cosmology called LCDM has its origins in the work of great scientists including Einstein, Friedmann, Slipher, Hubble, Lemaitre, and Gamow. Lemaitre’s 1930s “Cosmic Egg” or “Primeval Nucleus” was the basis for the Big Bang model. In its new variant called LCDM, “L” represents the cosmological constant Lambda and “CDM” represents Cold Dark Matter. These two components, L and CDM, account for 95 percent of the mass–energy content of the Universe. Edwin Hubble correctly showed in the 1930s that galaxies are distributed on the largest scales in a homogeneous and isotropic way, but on a more local scale of 300 million light-years Hubble failed to recognize significant inhomogeneities. Hubble and Humason validated the velocity–distance relation for galaxies and galaxy clusters demonstrating the expansion of the Universe. They did not call out how significant the velocity–distance relationship would become in our effort to determine the 3D structure in the galaxy distribution.

An overview is presented of the breakthroughs that led to the discovery of cosmic voids and supercluster structure in the galaxy distribution and of those who did the work. The first step was the introduction of the image intensified camera to observatories in Arizona and its early use in the spectroscopy of galaxies. After a sufficient number of galaxy redshifts were collected, 3D maps of the local Universe were created. These maps revealed the dramatic structure including cosmic voids. Next, theoretical models were proposed to explain the observed structure. This step included a face-off between bottom-up evolutionary models in the west and top-down models from the USSR. As the models matured, it was recognized that normal matter (baryons) were insufficient to explain the observed structure in the galaxy distribution and that dark matter was a necessary new constituent. In recent years, cosmic voids have become a tool for precision cosmology.

Two challenges have been made regarding the Gregory and Thompson 1978 discovery priority of cosmic voids and the extended structure (called “bridges”) that connect one rich cluster with its nearest neighbor(s). The primary challenge is by the Center for Astrophysics group called CfA2 headed by Geller and her late collaborator Huchra. A less significant challenge is by Chincarini, one of the Arizona redshift survey members. These issues are discussed point by point starting with the CfA2 challenge. Table 8.1 summarizes the Arizona work as of 1984–1985 (just before the CfA2 survey began). This table as well as the extensive “timeline” table (Table 8.2) demonstrate that the CfA2 survey was a latecomer in the pioneering period and represents nothing more than an incremental step forward. The Chincarini challenge is based on data that belonged to our Arizona consortium (a subgroup headed by Tarenghi) and was published by Chincarini without permission.