our universe is after all not endless. it is a limited space
For the purpose of analogy, I spoke in physical terms. In my not-so-clear way I was talking primarily about "the pool of available human experience and knowledge." Experience and knowledge, being non-physical, are not subject to any physical limits of a conservative closed entropic universe.
Furthermore, who says that the universe is a limited space? That is exactly the issue Einstein faced, and why he introduced the cosmological constant into his energy-momentum tensor; he considered it unreasonable to believe that the universe would come to an end. Only later was it discovered that the universe does indeed seem to be expanding and evolving, making Einstein's ad hoc introduction of the cosmological constant unnecessary.
Also, in 1999 a paper by physicists Joao Mageijo and Andreas Albrecht was published that goes even further. Entitled Time Varying Speed of Light as a Solution to the Cosmological Problems, it is (currently) a very viable "revision" of relativity theory. Among other things, their theory allows for the spontaneous appearance/destruction of energy in the very early universe, which of course violates the so-called "fundamental" thermodynamic law of the conservation of energy, but adds impetus to the idea of an innately "open" universe.
No, my fellow physics-fanatic , I'd say the question about a "closed" universe is still very much up in the air. There remains the distinct probability for an endlessly fascinating exploration of the life it contains.
refs: Physical Review D; Introduction to General Relativity, Discover