>However, for the past ~6 billion years, distant galaxies have been speeding up in their recession, and the expansion rate, though still dropping, is not headed toward zero.
Am I not getting something here or is this sentence not make sense?
So the first derivative was already understood to remain nonzero forever[1], now we know that the second derivative probably will also remain nonzero, and the third is slowing down but still positive for the moment?
[1] IIRC in the 80s the big bang/big crunch model was preferred
Am I not getting something here or is this sentence not make sense?