JF Ptak Science Books LLC Post 560
Lucretius (95-55 BCE), in his Nature of the Universe, stated that since there is nothing outside the universe, it must be infinite: “the universe stretches away…just the same in all directions without limit”; it stretches far and wide into immeasurable depths. All that is in it, he reasons, is distributed equally and in the same way. But this is not the case, even in light of Edward Milne’s cosmological principle (1933), stating that all places in the universe is alike—which is true, except that there are vast disturbances in very large local areas that distinguish themselves from other places. The work of Gamow/Alpher/Herman (1939) and Penzias/Wilson in establishing the cosmic microwave radiation (CMB) shows that the observable universe to be very close to homogeneous and isotropic, and of course accelerating. (Suffice to say for this short post that there are models-- Friedmann-Lemaître-Robertson-Walker (FLRW) model for example-- which show the observable universe to be "weakly" inhomogeneous and anisotropic; but generally and on average the isotropic models stand.)
Perhaps the earliest published “bump” in the calm waters of the equal-distribution universe occurs with William Herschel (1738-1822), who in 1785 published a revolutionary image of the “Stellar System” (the Milky Way), showing its irregular pattern and the off-center placement of our sun amidst a panoply of other stars.(His image was remarkably and substantially correct, with the most grievous error being the placement of the sun too close to the center of the galaxy.) It was an image which bought the idea of a not-so-humano-centric idea into popular philosophy. This galacto-centric view remained until the work of Harlow Shapley's globular clusters in 1918.
This varied quite widely from the images of other astronomical observers and theorists such as Thomas Wright (1711-1786), who in his book An Original Theory of the Universe (1750) gives the Milky Way a friendlier, homogenous manner, overruling his earlier theory that the stars were “promiscuously distributed through mundane space” and delivering a theory of the stars organized in a regular pattern based upon a hierarchical center of some sort around which everything else was positioned. He also provided this fabulous image of the centers of galaxies as an immutable, transcendent force, the eye of the creator, rather than the simple, positive dot.
This idea was picked up by Immanuel Kant (1724-1804) who in his own work, The Theory of the Heavens (1755), expanded on the multiple centers of creation(s) (an “endless immensity in an unlimited plenum of creations”) of cascading and separate galaxies, and detailed a vast system of disk-shaped galaxies which revolved around centers which in turn revolved around other centers, becoming far vaster, though all were centered on a dominant, universal center.
But it was Herschel's images of the dots that came closest, longest, to the most accurate and appealing depiction of the universe, especially with the location of our solar system's principal dot seen as a dot among dots in a universe of dots.