After his previous experiences, Zhang Chenyan's subconscious kept reminding him that the brain-machine interface was causing him to confuse reality with the virtual world. This led him to overlook a crucial detail—the issue of Zhang Chenyan 2.0 and the clone.
For the first time since entering this world, he saw his own appearance through a mirror, a concrete object. The reflection he saw was not his avatar but his real-world self. Even more disturbingly, the clone he had just encountered also appeared as his real-world self, not the avatar.
Zhang Chenyan had seen the clone he created, Zhang Chenyan 2.0. That clone only mimicked his most commonly used avatar, not his real-world appearance.
Though it might be difficult to grasp, it all boiled down to one unsettling truth: in the "Elysium" project, all of his real-world privacy had been fully exposed.
In the so-called metaverse, data security is paramount, and such breaches should never occur. But now...
When 0810 mentioned the sudden spike in hash collision probabilities, he should have anticipated this. But back then, the issue wasn't as severe as it is now.
A chill ran down Zhang Chenyan's spine. Recently, these incidents—whether it was the increased hash collision probabilities or duplicate IDs—always seemed to erupt without clear patterns. They didn't cause immediate severe damage, making it easy to occasionally forget about them.
It felt like the proverbial "boiling frog"—a gradual erosion of something vital.
"What are you daydreaming about?" The girl beside him cautiously poked Zhang Chenyan with her finger before turning to the old man. "Grandpa, do you think something's wrong with him? Should we call the doctor again?"
Her words snapped Zhang Chenyan back to reality, and he hurriedly waved his hand. "No, it's nothing. I just spaced out for a moment."
Now fully recovered, Zhang Chenyan got up from the bed, not forgetting to express his gratitude. "Thank you both for saving me."
"It's nothing, just doing the right thing," the girl replied with a sweet smile, dimples showing.
"Young man, where are you from?" the old man asked, curious. "When I helped you onto the bed, I noticed your body was unusually cold. That's quite rare."
Zhang Chenyan recalled that the old man had repeatedly mentioned one thing—heat.
"I..." Zhang Chenyan hesitated, unsure how to continue.
He couldn't very well say he was playing a game called "Elysium" and ended up here, implying that the old man and the girl were just NPCs, mere data.
Setting aside the matter of offense, it's unlikely anyone would believe such a story!
In the end, Zhang Chenyan concocted a sci-fi narrative: "Honestly, I'm not sure how to explain where I'm from. You probably won't believe it. But in short, I'm a time traveler. Of course, if you don't believe me, you can just consider me a lunatic."
Surprisingly, the girl believed him, her eyes wide with curiosity. "A time traveler? Like in sci-fi movies, traveling through the past and future?"
Zhang Chenyan nodded. "You could say that."
He wasn't really a time traveler, and the story was just made up on the spot. If the girl wanted more details, she'd have to fill in the gaps with her imagination.
"Oh, I need to record the date and time here," Zhang Chenyan said, following the script he had created. "And you mentioned the heat earlier—what's the current temperature?"
"It's 2125," the girl replied, pointing to a calendar nearby. "To be exact, it's August 10th, 2125."
Afterward, she leaned in and whispered to Zhang Chenyan, "Are you going to log this in your travel journal?"
Zhang Chenyan had no choice but to go along with it. "Yes, I've logged it. My brain is connected to a brain-machine interface, so all my records are stored there."
He added that last part to avoid having to produce a physical journal if the girl asked.
"Do you believe him?" the old man asked, looking worriedly at his granddaughter.
Clearly, the old man had been mulling over how to respond to Zhang Chenyan's story for a while. His current statement was probably the most polite thing he could think of.
But it was evident that the old man leaned more towards the latter option—considering Zhang Chenyan a lunatic.
"I believe him," the girl replied enthusiastically, dashing her grandfather's hopes. "I mean, how cool is it to run into a time traveler?"
"What if... just what if... he's mistaken?" the old man suggested cautiously, not directly calling Zhang Chenyan a liar.
"But remember how cold he was when we found him, and even the doctor was baffled," the girl reasoned. "That alone shows he's special, doesn't it? And if you're worried about the brain-machine interface... well, people can 'live forever' now, so a brain-machine interface in the future isn't too far-fetched."
Unable to refute her logic, the old man shook his head and went back to his work.
Turning back to Zhang Chenyan, the girl continued, "Oh, you asked about the temperature, right? It's 37°C indoors, and it's probably over 40°C outside."
"Indoors, 37°C?" Zhang Chenyan was stunned.
"Yes," the girl pointed to a thermometer nearby. "You can see for yourself."
Zhang Chenyan had never seen such a thermometer before, but considering the year was 2125, it might be a product unique to that era.
"When will it cool down?" Zhang Chenyan asked.
The girl laughed, "This is the cooler weather! In a while, it'll get even hotter."
She sighed, "Grandpa says it used to be much cooler, with temperatures dropping to ten or twenty degrees."
As time passed, the oppressive heat began to overwhelm Zhang Chenyan, who had never lived in such high temperatures before. Now, he found it hard to adapt.
"By the way, where were you... before this?" the girl asked, correcting herself as she realized how odd the question sounded. "I mean, was it also hot there?"
Zhang Chenyan shook his head with a wry smile. "No, the temperature there was much lower. The surface temperature ranged from -10°C to -60°C. I know it sounds fantastical, but it's the truth."
To his surprise, the girl accepted this information readily. "So, was that place in the future or the past?"
"The future, more than four hundred years from now," Zhang Chenyan replied with a smile, then asked, "I think I heard you mention something about 'immortality' earlier. Did I mishear?"
The girl shook her head. "No, you heard right. Immortality. But it's only for the rich, not for people like us. It just means humanity has reached that level of technology."
Zhang Chenyan suddenly remembered something he had read in history books and quickly asked, "Are you talking about immortality achieved through a combination of biological science and medicine, using cloning and organ replacement?"
The girl nodded, adding, "You really must be from the future, because even though you don't seem familiar with this place, you know about that."
Zhang Chenyan smiled, unsure how to respond. As he gradually acclimated to the temperature, he started to sweat more.
In reality, the human body has only a few ways to dissipate heat—radiation, convection, and conduction.
Heat is transferred from a high-temperature area to a low-temperature one. When the ambient temperature is much lower than skin temperature, body heat is quickly dissipated, primarily through radiation, with a small amount through convection and direct contact with air. However, when the ambient temperature approaches skin temperature, the body needs to release heat more rapidly.
Normally, breathing can carry away some heat, but in this situation, the amount is too negligible to count.
In such high temperatures, skin cooling becomes crucial. Relying solely on heat transfer for cooling isn't enough, so the body's temperature regulation system triggers sweating to evaporate and carry away the heat.
However, when the ambient temperature exceeds skin temperature, heat transfer is no longer effective, and evaporation becomes the only means of cooling.
Evaporation... Zhang Chenyan looked at his fully clothed self and then at the old man in his vest and shorts. He finally understood why he was finding it increasingly unbearable.
But the thought of undressing now made him uncomfortable, especially with the girl nearby.
"Do you have some clothes I can change into?" Zhang Chenyan asked, embarrassed. "Or maybe some water? I'd like to take a bath."
"Water resources..." the girl started but then hesitated.
Zhang Chenyan quickly understood and corrected himself, "Never mind, just a change of clothes will do."
"You can use that room," the girl said, pointing. "I'll find some of Grandpa's clothes for you."
Zhang Chenyan nodded and was about to head to the room she indicated when he suddenly felt dizzy and nauseous.
Just as he was about to collapse, the girl caught him.
"Grandpa, come quick! Help me!" the girl called out in a panic. "Get the thermometer, quick. It might be heat exhaustion."
Clearly, the girl was well-practiced in handling such situations.
Heat exhaustion occurs in high temperatures or intense heat radiation when peripheral blood vessels dilate, and excessive sweating leads to reduced blood circulation, causing temporary cerebral hypoperfusion and fainting.
In his dazed state, Zhang Chenyan marveled at how he seemed to have gone from a freezing world straight into a furnace. What he was feeling now seemed too real to be just a simulation.
He had felt pain from physical attacks in the digital world, experienced tension in dangerous situations, but he had never felt the pain of illness before.
The pain from pathological conditions is incredibly complex, and in his mind, simulating this in the digital world seemed pointless. What's the purpose of making an avatar sick? It sounds ridiculous and serves no practical function.
"Grandpa, he's stopped sweating," the girl's voice trembled with fear.
Stopped sweating... Zhang Chenyan knew this meant his condition was worsening. When body temperature regulation fails, sweating ceases.
At this point, the skin becomes dry, and heat rapidly accumulates in the body.
On average, accumulating 3.49 kilojoules of heat per kilogram of body weight raises body temperature by 1°C.
Conversely, a 70-kilogram person only needs to evaporate 100 grams less sweat for their body temperature to rise by 1°C.
In this situation, within just a few minutes, body temperature can rapidly exceed 41°C, leading to cognitive impairment, confusion, or even coma.
"This is heat stroke!" the grandfather exclaimed after seeing the numbers on the thermometer. Living in such conditions, they were naturally familiar with this kind of medical knowledge.
"I'll go get the doctor. I'll go right now!" the girl shouted as she ran out. "Grandpa, strip his clothes off and drag him to the cellar where it's cooler."
As he watched the girl's retreating figure, Zhang Chenyan wanted to say it wasn't necessary. He wouldn't be here much longer, and he wouldn't really die. But the heat was making him increasingly disoriented, and his voice barely rose above a whisper.
The greenhouse effect.
He knew that all of this was because of the greenhouse effect.
Industrial development had progressed too rapidly... more accurately, every industry had developed too quickly.
It was as if countries were locked in a competitive race, each one pushing for more progress, more development.
Of course, this was a good thing. But with development came increased resource extraction and environmental destruction.
The greenhouse effect wasn't an accident, and reaching this stage wasn't a coincidence either. This was the bitter fruit that humanity had sown, and now they had to taste it for themselves.
What he was experiencing now was only one consequence of climate change, resulting in extreme heat.
In addition, heatwaves, tropical storms, tornadoes... would all follow in quick succession. As the girl had said earlier, soon, people might only describe the weather as hot or extremely hot.
This climate would lead to a sharp rise in cardiovascular and respiratory diseases and accelerate the spread and proliferation of infectious diseases.
Humans might extend their lives through cloning and organ replacement, but was that really a long-term solution?
In reality, this was just one small part of a vicious cycle.