Later, people would call a black hole formed by lowering the speed of light a “black domain.” Compared to black holes where the speed of light was unaltered, a reduced-lightspeed black hole had a much larger Schwarzschild radius. The interior was not a space-time singularity, but a fairly open region.
The helicopter continued above the clouds. It was now after 11 P.M., and the sun slowly set in the west, leaving only a slice visible. In the golden light of the midnight sun, everyone tried to imagine life in a world where light moved just below 16.7 kilometers per second, tried to imagine the creeping light of such a sunset.
By now, most of the puzzle pieces in Yun Tianming’s stories had fallen into place. But one piece remained: the paintings of Needle-Eye. The interpreters couldn’t figure out the dual-layer metaphor or find any bearing coordinates. Some thought that the paintings might be another bearing coordinate for the Moskstraumen, symbolizing the event horizon of the black domain. They reasoned that from an outside observer’s perspective, anything entering the black domain would be forever fixed at the event horizon, which resembled being painted into a picture. But most interpreters disagreed. The meaning of the Moskstraumen was very clear, and Tianming had used the Glutton’s Sea to act as a bearing coordinate. There was no need for another.
Ultimately, this last piece of the puzzle could not be deciphered. Like the missing arms of
I. The Bunker Project: This was the plan with the most hope for success, because it was based entirely on known technologies and involved no theoretical unknowns. In some sense, the Bunker Project could be viewed as a natural continuation of the development of the human race. Even without the threat of a dark forest strike, it was time for humanity to begin colonizing the rest of the Solar System. The Bunker Project just made the effort more focused and the goals clearer.
This was also a plan devised entirely by the Earth itself; it had not been described in the message from Yun Tianming.
II. The Black Domain Plan: This involved transforming the Solar System into a reduced-lightspeed black hole to broadcast a cosmic safety notice. Out of all the choices, this was the most technically challenging. Within a region of space fifty AU (or 7.5 billion kilometers) in radius, a physical constant had to be altered. This was dubbed God’s Engineering Project. The theoretical unknowns were immense.
But if the Black Domain Plan were to succeed, it would provide the most protection for Earth civilization. Setting aside its effect as a cosmic safety notice, the black domain itself would act as a highly effective protective barrier. Any external missile, such as a photoid, would be traveling at a very high velocity to produce the necessary destructive power, and would thus enter the black domain with a speed far in excess of the modified speed of light inside. Under the theory of relativity, such an object would have to proceed at the (new, low) speed of light as soon as it crossed the barrier, and its excess kinetic energy would be converted to mass. The first part of the object entering the black domain would suddenly slow down and acquire a much larger mass, while the rest of the object, still moving at the unaltered speed of light, would run into the first part, thereby destroying the entire missile with the impact. Calculations showed that even objects made of strong-interaction materials such as droplets would be completely shattered at the boundary of the black domain. Thus, a black domain was also dubbed “the cosmic safe.”
There was yet another advantage to the Black Domain Plan: Out of all three choices, it was the only plan that allowed humanity to continue to live on the familiar surface of the Earth and avoid an exile in space.
