Book cover of Eater.


Eater is a hard sci-fi novel by Gregory Benford. It follows a group of astrophysicists who discover a sentient black hole that is headed straight towards Earth.

I did not expect to enjoy Eater as much as I did! The book has a poor rating on Goodreads1 and almost no presence in online communities like Reddit. In fact, I only started reading it because I hit the “random” button on my ebook reader and it came up. I’m glad I did!

Eater is perhaps the hardest sci-fi book I’ve ever read. Almost all of the “action” takes place in the research center, as the scientists learn more about the Eater (the black hole), talk with it, and devise responses. This approach works well to make the book feel realistic. Most of what the characters learn happens after they make a measurement, discuss it, and deduce its meaning. The science is so solid that often I was able to predict the revelations before the characters because the data had obvious implications.

Some other examples of how hard the science is:

I believe that the hardness of the science partly accounts for the poor reception this book received. It feels like being thrown into a graduate physics class, which—as a physicist—is part of what made me enjoy it so much.

The realism made me worry that the introduction of the Eater—a sentient black hole—would completely break the immersion. But Gregory Benford provided a convincing explanation: the black hole isn’t alive; the intelligence is encoded in the magnetic fields surrounding it. Magnetic fields can store data and perform computations, so it’s plausible that an intelligence could exist within them.

The characters are probably the weakest part of the book, but they’re adequate. The main characters are:

The book takes place in 2023,4 and it’s fascinating to see how the author predicted the future we now live in. Far more telescopes were built and launched than in reality. Instead of rockets, air-launch-to-orbit is the primary method for getting spaceships off the ground. Pocket computers exist, but not smart phones; phones are still attached to the wall. Computing power feels lower than we have now, and while the internet exists (as it did when the author was writing), it seems structured differently, with more small nodes instead of massive companies. Self-driving cars have completely replaced taxis. The US government has formed a new, all-powerful agency that takes charge during crises.

The blend of very hard sci-fi and thriller-like pacing makes Eater an engaging read; I could hardly put it down! I’m looking forward to exploring more of Gregory Benford’s work, particularly Timescape or Cosm, in the near future.

  1. A score of 3.50 with only 735 ratings. 

  2. The Eater itself is, of course, a MACHO

  3. As Patricia Byrd wrote in Star Trek Lives: Trekker Slang:

    Mary Sue stories—the adventures of the youngest and smartest ever person to graduate from the academy and ever get a commission at such a tender age. Usually characterized by unprecedented skill in everything from art to zoology, including karate and arm-wrestling. This character can also be found burrowing her way into the good graces/heart/mind of one of the Big Three [Kirk, Spock, and McCoy], if not all three at once. She saves the day by her wit and ability, and, if we are lucky, has the good grace to die at the end, being grieved by the entire ship.

  4. The author intentionally hides the date at several points, but slips up once and mentions “Since the Gulf War 32 years ago…”.