Roger Penrose has suggested that the exponential expansion of the universe will ultimately dilute everything so much that it will iron out all space-time features. Black holes will evaporate, stars and galaxies will disassemble, and even elementary particles will decay into photons. Finally, the late universe will resemble the early universe except in size. Penrose magics this problem away by suggesting that, at these extremes, scale becomes irrelevant, and the late universe can become the early universe of the next in the series.
