Question about the cosmological constant in Einstein's work

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Was watching some documentaries and got confused about something.

People say that Einstein unintentionally predicted that the universe was expanding, and that he inserted the cosmological constant to represent a force pulling it back in. But other sources seem to imply that the universe was supposed to be collapsing under gravity, and he inserted the cosmological constant to represent a force pushing it out (which is what it seems to represent today).

So which is it? The idea of the cosmological constant being a force pushing against gravity makes the most sense, but that seems to contradict the normal claim that Einstein was the first to find that the universe should be expanding.
 

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Orodruin
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People say that Einstein unintentionally predicted that the universe was expanding, and that he inserted the cosmological constant to represent a force pulling it back in.
What people? Please provide references.

The prediction of GR was that the universe could not be static, which was the reason for introducing the cosmological constant. Had it not been introduced, then a direct consequence would be that the universe either expands or contracts (or is just in the transition between the two).
 
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What people? Please provide references.
One example is this interview with Ed Copeland...

At 0:10, he says "Einstein was really quite resistant to the idea that the universe is expanding, and he worked very hard to stop it."
He then refers to the universe "evolving" instead, but at 10:40 he says "for this to work, for him to stop the universe from expanding..."

The prediction of GR was that the universe could not be static, which was the reason for introducing the cosmological constant. Had it not been introduced, then a direct consequence would be that the universe either expands or contracts (or is just in the transition between the two).
That makes some sense, which would imply then that people are just giving Einstein credit for predicting that the universe would be evolving, and some people use the term "expand" when in actuality the cosmological constant was either something that stopped contraction or something that could stop either one depending on how you define it?
 

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