Encyclopedia: Gravitational Wave Antenna

The Gravitational Wave Antenna is one of the most crucial technological devices in the Three-Body universe. Installed on the Gravity and at Earth's deterrence control center, it's used to broadcast Trisolaris's coordinates to the universe — the core tool for executing Dark Forest Deterrence.

Unlike traditional electromagnetic wave communication, the gravitational wave antenna uses gravitational waves — ripples in spacetime itself — to transmit information.

Unblockable: Gravitational waves penetrate all matter — no technology can block them

Extreme range: Gravitational waves barely attenuate across cosmic distances

Light-speed transmission: Same speed as electromagnetic waves

Untraceable: The source of a gravitational wave transmission cannot be located by third parties

The underground deterrence control center (50m deep) housed three gravitational wave antennas arranged in a triangle. The Swordholder's switch directly activated these antennas. A single broadcast required energy equivalent to the entire world's annual electricity generation.

Gravity was humanity's most advanced interstellar warship and the holder of the secondary deterrence platform. Its gravitational wave antenna was installed at the ship's core as a "backup" — if Earth's deterrence failed, Gravity could restore deterrence through broadcast.

In 2090 AD, after Cheng Xin took over as Swordholder and deterrence collapsed, Trisolaris invaded Earth. The crew of Gravity learned of this. Facing the choice between "return and accept Trisolaran rule" or "execute the broadcast," the ship decided through democratic vote: broadcast Trisolaris's location to the universe.

This vote was the most important democratic decision in human history. From millions of kilometers away, Gravity sent a universe-changing message via gravitational waves: "The coordinates of Trisolaris are as follows..."

Ironically, the gravitational wave broadcast ultimately led to the destruction of both civilizations. Years later, the Singer civilization received the broadcast coordinates — it didn't care whether the broadcaster was human or Trisolaran, it only knew these coordinates were exposed. A dual-vector foil was dispatched to the Solar System.

Interestingly, when Liu Cixin wrote about gravitational wave antennas in 2006, gravitational waves hadn't been experimentally confirmed. It wasn't until 2016 that LIGO first directly detected gravitational waves, confirming Einstein's century-old prediction.

Future: Can humanity actually build gravitational wave communication antennas?

Science is catching up to science fiction. Perhaps in the near future, Three-Body's gravitational wave antennas will become reality.