Looking for a book

[Lighthawk]

I'm trying to dig up the title to a book I read at some point between 5 to 20 years ago.

The story is about the descendants of a space ship that some generations back managed to get itself stranded in an alternate universe where the force of gravity is far greater than it is in our universe. So strong in fact that a human body produces a gravitational field that you can feel when standing near them. The people live inside the alt uni's version of a nebula and mine the iron core remains of stars, which are only a few miles across and burn through their lives in days. They eventually come up with some plan to escape that I can't remember and have to face a creature that uses black-holes as cells.

If anyone knows the title, I'd much appreciate it.

[Mikey]

I sure don't know it, but how come the people didn't die spectacularly within the first fraction of a second of encountering a massive body in the new universe?

[Lighthawk]

Because there aren't any massive bodies in that universe, not of the type that exist in ours. Stars are as big as things get, and they achieve enough mass to start gravity driven fusion at just a few miles across.

[Mikey]

But, then, if gravity is that strong, wouldn't stars of that size - or even planets - exert enough gravity to have an event horizon?

Even worse, if gravity is that strong in this other universe, wouldn't the Chandrasekhar limit be incredibly low?

[Lighthawk]

I'm sure there was plenty of issues with the science, but it's been too long since I read it to remember enough to pick it apart.

On the plus side though, I managed to find it. Raft, by Stephen Baxter.