[Bob Campbell]

The source of Einstein's quote indicating discontionuous structures is given in my TOE Article "Gravity & the Void: Tip of a Toe Iceberg."

His disenchantment with the divergent directions that physics and the philosophy of physics took is well known. Many quotes are possible. Two quotes are as follows:

Einstein:
“The only justification for our concepts and system of concepts is that they serve to represent the complex of our experiences; beyond this they have no legitimacy. I am convinced that the philosophers have had a harmful effect upon the progress of scientific thinking in removing certain fundamental concepts from the domain of empiricism, where they are under our control, to the intangible heights of the a priori. For even if it should appear that the universe of ideas cannot be deduced from experience by logical means, but is, in a sense, a creation of the human mind, without which no science is possible, nevertheless this universe of ideas is just as little independent of the nature of our experiences as clothes are of the form of the human body.”(From his "The Meaning of Relativity," 5th Ed.)

Einstein:
“I see on the one hand the totality of sense-experiences, and, on the other, the totality of the concepts and propositions which are laid down in books. The relations between concepts and propositions among themselves and each other are of a logical nature, and the business of logical thinking is strictly limited to the achievement of the connection between concepts and propositions among each other according to firmly laid down rules, which are the concern of logic. The concepts and propositions get “meaning,” viz., “content,” only through their connection with sense-experiences. The connection of the latter with the former is purely intuitive, not itself of a logical nature. The degree of certainty with which this relation, viz., intuitive connection, can be undertaken, and nothing else, differentiates empty fantasy from scientific “truth.”(From "Autobiographical Notes," written at age 67.) (Einstein intuitively knew what later became established as scientific fact by Sperry's experiments on split brain patients that the intuitive and language hemispheres of the brain function independently and that it is the intuitive right hemisphere that integrates experience holistorically.)

Einstein repeatedly pointed out limitations to General Relativity on various occasions. For example in the Appendix to the Second Edition of "The Meaning of Relativity" (Pg 129) he writes:

"... For large densities of field and of matter, the field equations and even the field variables which enter into them will have no real significance. One may not therefore assume the validity of the equations for very high density of field and of matter, and one may not conclude that the "beginning of the expansion" (his quote marks) must mean a singularity in the mathematical sense."

His later work was sidelined largely because of the direction that Quantum Mechanics took. Even though QM and GR have never been married they are both used in Big Bang Cosmology. It seems to me it is a swamp of ad hoc assumptions to plug holes that forever keep appearing. In the absence of an alternative paradigm researchers keep reaching further into the realms of fantasy to keep shoring the theory up.

One of the basic assumptions on which General Relativity is based is that matter is smeared out more or less evenly on a cosmic scale.