Zhou Yi said, "What should I call you now?"

"Just call me D."

Mr. D's face was a rectangular display fixed on a metal skull, showing a waveform spectrum analysis diagram—essentially a visualization of audio signals, commonly found on audio equipment screens.

"How did Mr. Zhou come into contact with time?"

After posing the question, D interrupted himself: "Perhaps I should first talk about my own situation."

"In the Taishan Knight Order, everyone has different directions of exploration."

"I study time."

"There are many peculiar phenomena in the field of time, and the old humans had already accumulated quite a few discoveries. For example, the twin paradox, the Hafele–Keating experiment of 1971, where a plane carrying an atomic clock showed a deviation of 59 nanoseconds after flying."

"Assuming an astronaut travels at near light speed for a year and returns to Earth, they might find that ten years have passed on Earth. This illustrates that the faster the speed, the slower the time."

D's waveform fluctuated slowly: "There's also gravitational time dilation. According to observation and inference, one hour near a black hole's event horizon equates to thousands of years on Earth. Satellite clocks, due to weaker Earth gravity, run 45 microseconds faster every day compared to the surface."

"And then the delayed-choice experiment, where a photon's behavior as a particle or wave can be influenced by the experimenter's later actions, thus the future can alter past observational results... This was proposed by Wheeler in 1978 and confirmed by the quantum erasure experiment in 2011."

"On a cosmic scale, temporal anomalies are even more numerous."

"Sustained observation of unstable quantum systems, like radioactive atoms, can 'freeze' their decay processes. It seems as if time has stopped."

"In a 1989 experiment by old humans, they used lasers to frequently observe beryllium ions, extending their excited state lifespan by a hundred times."

"General relativity predicts that the curvature of spacetime at a black hole's center is infinite, with time dimensions and spatial dimensions swapping places. The future thus turns from imaginary to real, becoming a 'direction' one can choose to enter."

Having presented many existing cases in one breath,

D said, "These phenomena indicate at least three things."

Subtitles and a branching explanation diagram appeared in sync on its face.

"Firstly, time is not absolute; it's an emergent property of the universe's complex relationships.

"Secondly, the observer effect and time interact; 'now' on the quantum level can change the 'past.'

"Thirdly, the uniqueness of life; there's a gap between the time perceived by organisms and physical time."

Apart from the second point, Zhou Yi deeply sensed the other two.

Especially the third point, which aligns with the Golden Tree's distinction between real time and perceived time.

D said gravely, "Time appears to be so variable, affected by many environmental changes, that it's hard to define as an objective standard measure."

"Later, I discovered vast regional time discrepancies in mantle areas, which grew larger with deeper underground exploration."

"I consulted Universal Time and Time Meters, and they gave me a conclusion contrary to common sense. Time might not be a form of energy like gravity or temperature but a special material."

"This material can't be seen or touched, yet they have their basic units. An ancient timekeeping tool used by old humans—a sandglass—bears some resemblance to real time."

"Time in every spatial region, be it an ant's body, a house, or a piece of land, is distributed like a sandglass. They are special material particles. Old humans proposed a theory of time crystals, which closely resembles this."

"That theory states time crystals are quantum structures 'perpetually moving' in the Time Dimension, just like ordinary crystals have repeating atomic structures in space, time crystals show periodic changes in time."

"Imagine time crystals as quantum clocks moving perpetually without needing winding; their hands jump at regular intervals. These crystals are the more microscopic basic units of time, their manifestation on the material side... though they can't be directly observed."

"The world is evenly distributed with countless sandglasses, within which time crystals continuously undergo spontaneous motion, their states cycling. Like how 0 represents low voltage and 1 corresponds to high voltage forming the basic physical structure of Mechanical Life, the sandglass-time also contains crystals representing different states, as life's 0s and 1s in time."

"I know this is somewhat intricate and complicated, but please allow me to elaborate a bit more, for this theoretical content is indispensable and relates to the ultimate conclusion..."

At this point, D observed Zhou Yi's expression.

Seeing that he wasn't impatient, D continued: "I traced it all the way back to the first enormous underground Bone Fish that left Earth."

"After the Bone Fish flew to the sky, there was an uninhabited island it passed over, where time was persistently 7 minutes slower than surrounding areas."

"The Time Meter recorded all of it."

"I rushed to the island right away, spent two months there using an extension, and found the cause under the island's sea floor. There was a semi-civilized taxi circling the island continuously."

"Inside the taxi, a bizarre membrane formed, blocking all external observations. Approaching it, one could clearly feel the internal clock becoming chaotic..."

D recalled, "Entering the car was easier than I thought, without any obstacles. I waved it down to stop, opened the door, entered—just like that."