Probability Space by Nancy Kress

Kaufman was back in the Neury Mountains, listening to Dieter Gruber and Tom Capelo argue about mental effects of the buried artifact. Dieter Gruber, cheerful, insensitive, a huge blond hulk engineered according to somebody’s ludicrously exaggerated idea of a Teutonic prince. Dieter, without whom the Protector Artifact would have stayed buried in the submontane cavern where it had lain for fifty thousand years.
    “Ach, Lyle, is that really you? You are back? Ann, Ann, come quick, it is Lyle!”
    So Ann Sikorski was still alive, too. Thanksgiving flooded Kaufman. One more death off his conscience.
    “Lyle?” Ann’s voice, quieter than her husband’s, and infinitely more steely. Ann the idealist, who had stayed behind in the civilization humans had ruined.
    “Yes, it’s me. And Marbet, too. We’re at the old landing site near Gofkit Jemloe. Are you in the village? Or at Hadjil Voratur’s?”
    “No,” Ann said quickly. “Don’t go either place. We’re in a different village, half a day’s walk from you. But you can’t … Do you have a surface craft?”
    “No. Only a misbegotten cross between a flyer and a shuttle. It won’t make surface hops.”
    “Then don’t move. Dieter will come to you.”
    “Come to me? But why—”
    “I said don’t move .” The link went dead.
    Marbet studied his face. She said, “They think it’s too dangerous for us to be out there by ourselves.”
    He didn’t answer. Travel on World had always been open, easy, safe. In a monolithic culture in which any act of violence would hurt the perpetuator almost as much as the victim, violence had been rare. Before.
    They went back inside the flyer/shuttle, Kaufman feeling something between ridiculous and scornful. He had been a soldier, with combat experience. Marbet and he had the latest personal weapons available to civilians. And Ann Sikorski wanted him to wait before facing a hypothetical mob of short aliens with no history of warfare and a technology level stuck at hand-forged bicycle wheels. His mood, usually calm, blackened. Marbet left him alone.
    They left the door open, sat, and waited. Eventually a smear appeared on the horizon, moving very fast. It grew into Dieter Gruber on a motorized bicycle. He raced up to them and threw himself off the bike, enveloping each of them in a huge bearish hug. “ Lieber Gott ! You are really here!”
    “Yes,” Kaufman said; disentangling himself from Gruber. Kaufman was not a hugger. “And more to the point, so are you. You are well? And Ann?”
    “I am very well. Marbet, beautiful as ever! But why do you come? Is there another scientific expedition?”
    “No,” Kaufman said, “no expedition.”
    “We came to rescue you,” Marbet said mischievously. She had received Gruber’s hug with pleasure, and her glance at Kaufman said that the exuberant Gruber, bursting with health, obviously did not need rescuing. “But why wouldn’t you let us come to Gofkit Jemloe?”
    Gruber instantly sobered. “We are not in Gofkit Jemloe. Hadjil Voratur … it is not good.”
    “Tell me,” Kaufman said. Here it came: What he had done to this planet.
    “Hadjil Voratur and his son Shosaf are dead. Killed by marauders, during the time after shared reality went away. They would not believe when we told them not to try … anyway. Gofkit Jemloe is an armed camp, under a cousin of Voratur’s, a very dangerous person. Febin Frillandif. He has recruited an army … Worlders were peaceful, you remember.”
    As if Kaufman could forget.
    “Peaceful, yes, but they are human. Well, no. But when everything changed, those scum who had been controlled by shared reality were controlled no longer. Frillandif is subduing all the villages around, one by one. He is building an ‘empire.’”
    Like Stefanak. Kaufman said, “And you and Ann and Enli?”
    “We are in Enli’s village, Gofkit Shamloe. They have tried to attack, but Ann and I brought with us some weapons they of course had never seen … and