Genius Playground

”Ugh, the elevator was so busy. But I’ve got the takeout~”

A cute figure skipped into the doorway of the hospital room.

It was Cheng Mengxue.

She walked in wearing a light blue dress, carrying a takeout bag.

Seeing a familiar face, Jiang Ran felt a little more secure.

”Why am I in the hospital?”

He asked urgently,

”Did the Time SMS send successfully? Was Xu Yan saved?”

”Huh?”

Cheng Mengxue was taken aback for a moment.

But then she chuckled.

”Just as we expected. Jiang Ran, you just experienced a temporal shift, didn’t you?”

”From your perspective... one moment you were sending the message in the club room, and the next you opened your eyes and were lying in the hospital, right?”

Jiang Ran nodded.

Three days ago, they had already figured out the principles of the Time SMS, the patterns of the temporal shifts, and Jiang Ran’s unique trait of retaining memories of the original history.

Not to mention, this kind of situation—where Jiang Ran would suddenly be alarmed, his memories out of sync—had already happened twice.

So, Cheng Mengxue immediately understood what had happened.

”We received the message on March 26th, which means it must have been sent on March 29th. That also means the temporal shift affecting you was bound to happen on March 29th.”

”So, I’ve been staying by your side all day today, just waiting for your memories to go out of sync again so I could be the first one to explain things to you.”

Cheng Mengxue placed the takeout on the table, her train of thought perfectly clear.

”I see.”

Since everything was happening within their understanding of the rules, there was no need to be nervous.

”Was Xu Yan saved?” That was Jiang Ran’s most pressing question.

”Of course!”

Cheng Mengxue gave him a thumbs-up.

”We’re so amazing! We actually saved a life! This feeling is incredible!”

Phew...

Jiang Ran let out a breath, finally able to relax completely.

”So?”

Cheng Mengxue looked at him.

”Is it the same as before? You only have memories from before the ’Time Travel,’ and not for the past three days?”

”Yes, it’s the same.”

After a pause, Jiang Ran smiled.

”I have to correct you on one concept. My situation isn’t what you’d call Time Travel.”

”Time Travel in the traditional sense usually involves traveling along the scale of time, like going from the present to the past, or from the present to the future. You know, the kind you always see in Hollywood movies.”

Cheng Mengxue tilted her head.

”Isn’t it the same?”

”Not quite.”

Jiang Ran continued to explain,

”Look at my situation. There’s no travel along the scale of time. I didn’t go back to the past or into the future. My personal timeline has been continuous.”

”One second I was sending the message, the next second I appeared in the hospital. My spatial location changed, but time didn’t. It’s still March 29th. I haven’t gone anywhere on the time scale; I’ve only moved through space.”

Cheng Mengxue seemed to understand.

”So what would be a good name for your situation?”

”Hmm...”

Jiang Ran thought for a moment.

He recalled the ’Parallel Worlds and Worldline Theory’ that Teacher Zhang Yang had lectured on in their general education course.

At the time, Teacher Zhang Yang had proposed a rather interesting term.

”Worldline Jump.”

Jiang Ran said softly,

”This act of crossing worldlines without moving in time... I think ’Worldline Jump’ is a more fitting term to describe it.”

”Teacher Zhang Yang talked about it when we took that general education class together. Weren’t you listening?”

”Nope,” she said matter-of-factly.

”...Alright then.”

Jiang Ran took a pair of disposable chopsticks from the takeout bag, snapped them apart, and arranged the two sticks one above the other.

”Let’s assume the top chopstick is ’World Line A.’ It represents the original history, the worldline where Xu Yan drowned, we argued, and we voted on whether to save her.”

”On March 29th in World Line A, we sent a Time SMS to the past, to March 26th. History began to change from that moment.”

”Therefore... a new historical trajectory was spurred into existence, and thus, a new worldline was born.”

He wiggled the bottom chopstick.

”This new worldline is called ’World Line B.’ It represents the altered history, the one where we got the news in advance, prevented the tragedy, saved Xu Yan, and I’m lying in a hospital bed.”

Ohh~

Cheng Mengxue was quick on the uptake.

”So, in other words, according to this theory, we’re in World Line B right now.”

”Exactly.”

Jiang Ran liked people who understood things right away.

”After that Time SMS was sent, the temporal shift occurred, the original historical trajectory was altered, and World Line A ceased to exist.”

”So, in effect, we all jumped from World Line A to World Line B. Or, to put it another way—”

”The spacetime we inhabit, as a whole, jumped from World Line A to World Line B. That includes you, me, this world, and everything in the universe. It all jumped over from a spatiotemporal perspective.”

Cheng Mengxue nodded.

”I get that part. Because the historical trajectory has changed, the events that happened in World Line A shouldn’t exist anymore.”

”But that still doesn’t explain the issue with you—”

”Why are you the only one who retains memories of the original World Line A after the worldline changes?”

Jiang Ran spread his hands.

”Who knows?”

”Hey, let’s not worry about that for now. Just hurry up and tell me what happened. How did we save Xu Yan? And how did I end up in the hospital?”

Cheng Mengxue told Jiang Ran to eat his takeout first, then began her story...

This is what happened:

Three days ago, on March 26th at 10:00 AM, Cheng Mengxue’s phone received the Time SMS, informing them that Xu Yan was going to drown.

They immediately sprang into action. They borrowed a buoyancy life jacket from the swim club, then rushed out of the school gates and hailed a cab to Qing’an Bridge.

The buoyancy life jacket was filled with air cushions and foam, so even someone who couldn’t swim at all could easily float in the water while wearing it.

There was some traffic on the way, but by the time the three of them reached Qing’an Bridge, they had just run into Xu Yan.

They had barely exchanged a few words when the cries of children came from the waters of the Turbulent River.

Under the bridge, two children were flailing in the water. They had fallen in upstream and been carried down by the current. One of them was already unconscious and motionless, while the other was struggling and crying for help.

At that moment, Xu Yan didn’t hesitate for a second, swinging her leg over the side to jump into the river and save them.

Luckily, Jiang Ran had quick reflexes and managed to grab her.

The current was swift. Seeing that the two children were about to be swept away, Jiang Ran gritted his teeth, snatched the buoyancy life jacket from Cheng Mengxue’s hands, and vaulted over the bridge into the river.

He had learned to swim as a child and was a decent swimmer. After jumping into the river, he immediately put on the life jacket and swam toward the drowning children.

The rescue wasn’t very difficult; he soon pushed both kids to the shore. After some chest compressions, the motionless child also coughed up river water and came to.

It could be called a perfect rescue.

The only person who got hurt... was Jiang Ran.

He wasn’t sure what had cut him, but it was only after getting back on shore that he discovered a gash on his right arm, which was oozing blood.

But it wasn’t a big deal. They went to the hospital, had the wound cleaned and stitched up, and got it bandaged.

”And that’s what happened,” Cheng Mengxue concluded.

But Jiang Ran had a question.

”I’m not that fragile, am I? A small wound like this, and I need to stay in the hospital for three days?”

”Not at all.”

Cheng Mengxue waved her hand dismissively.

”We went back to school that same day. We came to the hospital today specifically to get your dressing changed. It seems like your wound got a little infected and inflamed, so the doctor had you lie down for an IV drip.”

”Alright.”

’With that, the memory loop closed, and the logic was sound.’

’No, wait.’

’There was still one more crucial thing!’

”The text message.”

Jiang Ran put down his bowl and chopsticks and looked at Cheng Mengxue.

”Xiaoxue, this time, your phone...”

”Exactly how many messages did you receive?”