Our descendants will have far more effects on the universe if they become grabby, and most of their expected effects come in that scenario. Even so, as I discussed in my last post, most see only a small chance for that scenario. So what if we remain a non-grabby civilization? What will be our long-term legacies then?

In roughly a billion years, grabby aliens should pass by here, and then soon change this whole area more to their liking. At that point, those grabby aliens will probably have never met any other grabby aliens, and will be very interested in estimating what they might be like, and especially what they might do when the two meet. And one of their main sources of concrete data will be the limited number of non-grabby alien civilizations that they have come across.

Which is all to say that these grabby aliens will be very interested in learning about us, and should be willing to pay substantial costs to do so. So in the unlikely event that our civilization could last the roughly billion years until they get here, those aliens would probably pay substantial costs to protect and preserve us, if that were the cost of learning about us. Of course if they had more advanced tech, they might have other less-fun-for-us ways to achieve that goal.

In the more likely case where we do not last that long, the grabby aliens who arrive here will be looking for any fossils or remnants that they could study. Stuff left here on the surface of the Earth probably won’t survive that long, but stuff left on the surface of geologically dead places like the moon or Mars might well. As could stuff left orbiting between the planets or stars.

Anticipating this outcome, some of us might try to leave data stores about us for them to find. Like we did on the Voyager spacecraft. As our long term legacy. And some of those folks might try to tie their personal revival to such stores. I’m not sure how it could be done, but if you could mix up the info they want with the info that specifies you as an em, maybe you could make it so that the easiest way for them to get the info they want is to revive you.

Of course if a great many people tried this trick, they might bid the “price” down very low. “They want you to revive them for a week to get your info; I only ask one day.” So elites might regulate who is allowed to leave legacy data stores, to keep this privilege to themselves.

Long before grabby aliens got here, they would pass through spacetime events where we’d be active on their past light cone. In fact, sending out a signal from here in most any direction should eventually hit some grabby aliens expanding in our direction. So if we could coordinate with them to send signals out just when they’d be looking at us (such as by sending signals following those from a cosmic explosion), we could tell them about us, and influence them, via such signals.

Some of us might want to try the trick of mixing up their em code with the info aliens want, to force their revival at the receiver end, but the bandwidth to send signals to be received in a 100Myr is rather small. However, as I’ve discussed before, one key function for such signals is that they can prove that they were sent on the date claimed. Later data stores found here are less trustworthy, as they could have been modified in the interim. So perhaps we could send out hash codes to verify datastores saved here now.

We could of course also tell them about any other non-grabby aliens we have discovered. But they’d probably already know about them, assuming they have vastly greater capabilities and tech at least as good as ours.

So is this an exciting legacy to you? A few stories about us that might help some other ambitious civilization calibrate how yet other ambitious civilizations will react upon meeting? No, well then maybe we should work on figuring out how to become grabby ourselves.

Added 4Nov: I missed a big potential legacy: Non-grabby aliens could help to mediate between and coordinate grabby aliens. Before two grabby aliens civs meet, they may have both seen and received messages from dozens of the same non-grabby civilizations. Messages sent by those mediators might set expectations and reference points that help the grabby aliens to coordinate. They might even distribute entangled qubits.

Such messages would be more credible if they embodied costly signals. So what could a non-grabby alien civ do, and show they did, to convince grabby aliens re their expectations of what will happen when grabby aliens meet?