The World at the End of Time Read Online Free PDF Page B

the future, because the funding battles had begun all over again. The building of Argosy was still going on, but at a snail’s pace.)
    The ships all had one thing in common, though. To travel through interstellar space, each of them had to eat part of itself.
    So the new shape of his ship was startling to Viktor. His eyes refused to recognize it. Mayflower was far shorter and stubbier than when last he had seen it, ten decades earlier. The long mass thruster, shaped like a skinny tulip, stuck straight out from the back of the ship where once it had been almost completely within the fabric of the ship itself.
    To power its flight to the new star, Mayflower had fed more than half of itself into the plasma reactors already.
    The string ball of fuel—twisted cables, thick as girders, of antimatter iron—had unraveled and reacted with the normal steel structure that had once enclosed it. The normal iron and the antimatter iron destroyed each other to produce the vast flood of charged particles that drove the ship.
    Of course, not all the real iron in the ship was annihilated in the suicide pact with the anti-iron. Even interstellar travel didn’t need that much energy. Most of the normal iron simply flashed into plasma and streamed out the thrust nozzles as reaction mass. There was no mystical reason why the normal matter had to be iron, either—iron didn’t need anti-iron for the two to annihilate each other; it was just what was easiest to spare.
    It was a very efficient reaction. Much better than that pathetic “atomic power” the old people used to use.
    It is always true that e = mc 2 , all right, but it is not easy to get all of the e out of the m. The sort of nuclear power plant that human beings built in the late twentieth century had a lot of mass left over when its reactions were complete. Ninety-nine point nine percent of the fuel mass remained mass and stubbornly refused to turn into energy at all.
    But when antimatter reacts with an equal amount of normal matter no mass whatever is left. It isn’t only a tenth of a percent of the mass that becomes driving force when you react normal matter with its antiparticles. It is all of it.
     
    By the fourth day after Viktor’s unplanned defrosting, the crew of Mayflower had gotten over their first heart-stopping fear. The flare star showed signs of dimming. The situation didn’t seem critical, exactly. Puzzling, yes: Why had a very ordinary little K-5 star suddenly blossomed into flame? But it didn’t seem to be life-threatening.
    As panic subsided to surprised resentment aboard the New Mayflower, and then as the resentment changed to the work of coping with the consequences, Viktor Sorricaine’s days became routine. Everybody’s did. Fifth (Navigator) Officer Pal Sorricaine stopped being a navigator so he could become an astrophysicist, since one of his CalTech degrees had been on the dynamics of stellar cores. That was what was needed. The problem wasn’t just how to rig the light sails and decide how much thrust to order from the deceleration engines, it was to predict how long the flare would last—and precisely what its curve toward extinction would be.
    For that even Viktor’s father’s skills weren’t quite enough, so they defrosted Mayflower’s best astrophysical brain. And so Frances Mtiga (three months, or you could say ninety-odd years, pregnant) woke up, blinking, to find a dandy dissertation problem facing her.
    When she was thawed and bathed and fed and dressed Pal Sorricaine sat her before a screen and punched up the relevant menu for her. “This is what we’ve got on the flare star, Frances,” he said. “I’ve filed it under NEWFLARE, and here are all the relevant studies I’ve been able to find—they’re under FLARECITES—and this is the preliminary report that I sent back to Earth. That file’s marked TENTATIVE. Maybe I should have called it GUESSWORK. It doesn’t matter much anyway, Fanny. By the time any of this gets to Earth