My physics masters couldn't possibly be grand mages.

The crackling sound of burning firewood surrounded me.

The flames burning in the fireplace dispelled the chill in his heart.

Einstein remained seated on the sofa. He looked Char up and down but said nothing, simply picking up his water glass and taking a sip.

Tesla then slightly raised his chin.

The living room was quiet, but somehow, after experiencing a series of escapes during the apocalypse, I returned to this living room.

I saw these two people.

Char felt there was an invisible line of words above their heads:

【sense of security】

"Did you manage to convince Cindy?" Tesla asked from the side.

"It's a success, but there are still some other problems."

Xia said with a solemn expression.

He briefly recounted what had happened, then placed his computer on the table and opened the video he had just received from the armored vehicle.

Their entire escape and subsequent experiences after entering the base were recorded by the car's cameras, including Char's conversation with Cindy.

Moreover, because the armored vehicle had many cameras and many angles of view, it even saw a semi-transparent giant moving in the distance, as well as the protective door that was "cut" open by the giant's beam.

The living room was quiet for a while, and Xia didn't disturb Einstein and Tesla, who were deep in thought.

"It seems my initial assumption was correct," Einstein commented. "These things are definitely not something that can be dealt with by mass alone."

Tesla nodded, clearly agreeing with Einstein's words.

"It's not just the numbers that are weird, there are also the mechanics that are weird." Xia said helplessly, "Even Cindy can't do anything about it."

He paused, then continued, "Do you have any ideas?"

Einstein slowly rose, frowned, paced back and forth in the living room a few times, then went to the window and quietly gazed at the green of the Tower of Truth.

"Right now, all you can do is get rid of those 'ghosts'."

"Solve it?" Xia pointed to himself, somewhat bewildered. "Me?"

"Even Cindy can't handle that thing," he reminded her again.

"She also said it was simply because there was no corresponding counter-magic," Einstein said. "Moreover, it is still unknown whether she really used her full strength."

Xia didn't say anything, but frowned slightly, looking a little serious. He actually thought so too.

"We need to figure out what that thing is first." Tesla got up, walked to the blackboard, picked up the chalk, and wrote the word "ghost" on it. "What did you just say it was?"

Xia was taken aback for a moment, then realized, "The mechanism is strange."

Tesla smiled. "I like that word. The best way to crack a mechanism is to analyze it, understand it, and find its essence."

His smile quickly faded, and he said in a low voice, "Looks like it'll take some time."

After saying that, he turned and walked to the kitchen, starting up the hand-grind coffee machine. The copper grinder made a soft "click-clack" sound, creating a background white noise that soothed Xia's emotions, which were still recovering from the recent danger.

"Have you ever wondered how Cindy saw that thing?" Einstein suddenly asked.

Xia was taken aback. He frowned slightly and tentatively asked, "Sixth-tier perception?"

Einstein shook his head. "Sixth-order perception lies in the range, precision, and sensitivity of mental power, but it's all mental power. Theoretically, you should be able to perceive what she can, it's just a difference in time and distance. At its closest, those things were only separated from you by a layer of composite armor. If mental power can perceive them, you couldn't possibly not have noticed them."

Char didn't speak, but looked at Einstein, patiently waiting for his answer.

"Have you heard of the spectrum?" Einstein asked.

Xia recalled for a moment, "I think I learned some of it in junior high and high school, I still have some recollection of it."

After a pause, Einstein continued, "In 1665, Newton conducted an experiment using a prism to break down sunlight."

"When a beam of white light passes through a prism, you will see it broken down into a continuous band of colored light."

"Rainbow?" Char gradually unearthed this knowledge that he had learned long ago from the depths of his memory.

Einstein nodded. "The rainbow is the most famous spectrum in nature."

"The significance of the spectrum goes far beyond its beauty; it is also the 'fingerprint' that scientists use to identify substances."

Each element has its own unique spectral characteristics. For example, sodium appears yellow when exposed to flame.

Char nodded, seemingly puzzled but impressed. He asked, somewhat doubtfully, "But what does this have to do with Cindy being able to see those ghosts?"

"The existence of the spectrum proves that the world is far more colorful than humans can see," Einstein said, seemingly unrelated to the question. "But... have you ever wondered why humans can't see these things?"

"Because life is about 'evolution,' not 'evolution,'" Xia said, adding that he understood this basic common sense.

Einstein nodded. "The evolution of life is not a change from lower to higher, but rather a process of shaping species to survive successfully in specific environments; hence it is 'evolution.' It seeks the optimal solution, not the highest value."

When hunting or escaping predators on the grasslands, you don't need to distinguish whether the leaves in front of you are green with a hint of yellow or pure green; you only need to see a tiger moving.

At that moment, Tesla came out of the kitchen, carrying a coffee pot that emitted a bitter coffee aroma, and took over the conversation.

"Any biological system must make trade-offs between spatial resolution, temporal resolution, and spectral resolution."

Hyperspectral imaging takes anywhere from seconds to minutes to acquire data, while the situation changes rapidly during hunting or escaping, and this speed disadvantage can be fatal in the wild.

Furthermore, neural tissue is highly energy-intensive; even in simple vertebrates like fish, the visual system can consume up to 15% of their basal metabolic energy.

Einstein summarized on one side, "The vast majority of higher animals do not possess hyperspectral vision because it is detrimental to rapid reaction and low-energy survival."

But what if... it's a creature from outside the natural world? If something could overcome so many problems through superhuman physical abilities, could it possess such vision?

Einstein's words made Xia's head buzz. He immediately realized something and opened his eyes wide.

"Like... vampires?"

"Since it's not some kind of mental perception, then it must be a bodily function she possesses." Tesla smiled and poured himself a cup of coffee.

"We can assume that this 'ghost' is some kind of unknown substance. And as long as it's matter..."

Einstein looked at Char with intense gaze.

"It will most likely have its own unique spectrum..."