Chapter 135: The River of Time

"October 31st, Halloween Eve?" Harry looked at the date displayed on the TARDIS in surprise. "Why would Neville return to this time point? Does he want to catch Sirius?"

"If he really thought so, I wouldn't feel surprised," Doctor Doudou poked his head out of the door and took a look. "But his location seems a bit off."

This is the Forbidden Forest. Harry recognized it at once when he walked out of the door. It was the place where Neville and Hermione "had just been."

"I suspect Neville's spell is somewhat similar to Apparition, requiring high concentration," Professor Doudou commented. "If the time and place in your mind are slightly off, it's easy to run to the wrong place."

Harry and the two followed Neville invisibly. He was running toward the castle in a hurry at this time.

The Neville who appeared on the night of October 31st came from November 26th. He didn't know that Sirius was actually not a bad person, nor had he read the news of his arrest in the newspaper. At this time, he was still thinking about being a hero.

Neville always thought about being a hero, although many times it was not necessary.

Just when Harry was worried about whether he would run into Sirius, a behemoth blocked Neville's way.

It was the Hippogriff Buckbeak, who looked abnormally angry.

"Oh, you big guy, move aside," Neville muttered.

But Buckbeak didn't want to move aside at all, instead spreading its wings and pouncing toward Neville here.

Neville jumped backward quickly, dodging its attack. He looked a bit confused, not understanding why this big horse would run over and attack himself.

Buckbeak raised its front hooves and made another fierce charge, its sharp beak rushing straight toward Neville, looking like it wanted to poke him through.

"Alright, if you insist on looking for trouble," Neville pulled out his wand angrily. "Then I'll accompany you to the end."

Neville's fighting skills were much more exquisite than what Harry usually saw. He slid to the left, twisted his body to dodge Buckbeak's charge, and then immediately shot a Stupefy.

The spell hit Buckbeak's hind leg, but it had no effect, instead making it even angrier. The Hippogriff let out a sharp cry, flapped its wings and took off, pouncing toward Neville along the ground.

"Ascension," Neville said his most confident spell calmly. Harry only saw a dazzling array of afterimages, and then found he didn't know how he climbed onto Buckbeak's back, and was firmly grabbing its wing roots with his hands at this time.

Buckbeak flapped its wings, wanting to throw the wizard on its back off, but Neville's balance was very good, and he grabbed it very tightly. The airflow and scattered feathers made Harry dizzy, but in the end, Neville sat firmly on its back, and kept hitting its head with his fists.

Perhaps a bit dizzy from the beating, Buckbeak turned its body, fell from the air, and intended to land on its back to crush the enemy on its back.

Just at the moment of touching the ground, Neville used the Ascension Charm again, rolled to the right to receive the body, and stood up steadily, while Buckbeak didn't have time to react and fell heavily to the ground itself.

"Thick-skinned?" Neville raised his wand high. "Then try this!"

Dazzling light beams gathered at the tip of his wand, gradually forming a bright holy sword. Harry looked at his movements in surprise.

This was a spell he learned in the Avalon Hidden Realm last year. He didn't expect Neville to be able to perform it perfectly just by listening to the description once.

"Excalibur!"

The sword light fell. Buckbeak, who was still struggling to get up on the ground, had no room to dodge and was hit head-on by the scorching magic torrent. Even the tough fur of the magical animal couldn't take it.

After the spell ended, Harry found that Buckbeak was already in a mess, large areas of feathers were scorched, and it lay softly on the ground, seemingly having completely lost its fighting ability.

"Know who's the boss now, huh?" Neville said contemptuously.

This battle looked really wonderful, but it also made Harry feel very confused. Theoretically, although the Hippogriff is proud, it shouldn't attack a person it doesn't know at all for no reason.

After defeating (or even can be said to be seriously injuring) Buckbeak, Neville's consumption was not small, and he was squatting on the ground panting at this time.

"Doctor, look," Harry said in a low voice. "Neville's body is fading."

"It looks like he's going back to November 26th," the Doctor said while touching his chin. "His spell is a bit magical, this is almost... no, this is completely beyond existing technology, I really don't know how this spell operates."

In Harry's confused eyes, he continued to explain, "Normal time travel is irreversible, but the phenomenon on Neville is very thought-provoking. He briefly returned to the past, but returned to the time point before departure intact after his magic was exhausted."

"You should know the usage of the Time-Turner, which is that after you return to the past, you need to wait for the passage of time. When time returns to the moment before you traveled, your time and place are actually not fixed," the Doctor said. "Because time is always flowing, but Neville..."

"What do you mean time is flowing?" Harry asked. "Suppose I go back to the past, for example, from two o'clock back to one o'clock, when time returns to two o'clock, hasn't everything changed?"

"Before the TARDIS was invented, we thought so too," the Doctor said. "You would think you could go back to the past, but when you wait for 'now' to come again, everything hasn't changed."

"This is because the Time-Turner can only be used to send people to the 'past', but the enhanced TARDIS can travel arbitrarily in the 'past', which makes us discover a magical fact."

"For example, suppose time is a river, or rather, a river that has just begun to flow," the Doctor adjusted his wording. "It has two parts, the place where the river water has flowed, overflowing river water; or the dry riverbed that has not yet flowed."

"Hmm, I can understand," Harry said.

"And this river is flowing forward every moment, and every moment there are dry riverbeds filled with river water. Currently, we think this has no end," the Doctor said. "We people living in time are like fish in the river."

"Now, suppose there is a pair of hands, taking the fish out briefly, and putting them into the upstream river section. This is the role of the Time-Turner, you can understand, right?"

"So, you mean to say, there is an absolute 'now'," Harry said thoughtfully. "When we go back to the past, this 'absolute now' is still flowing forward?"

"That's right, after inventing the TARDIS, we noticed this," the Doctor pointed to this time machine disguised as a forest shed. "The TARDIS can move arbitrarily in this river of time, but cannot go to the completely unknown future, that is, the 'riverbed' part."

"But, if you say so, for example, I go back to one o'clock from two o'clock, and then wait normally for the return of two o'clock," Harry was a bit confused. "And in fact, time has flowed to three o'clock now?"

"That's right, you can use the TARDIS to go directly to three o'clock at two o'clock," the Doctor said. "And between two and three o'clock, Harry Potter does not exist in any corner of the world."

"This..." Harry instinctively wanted to ask how "absolute now" is defined, but he immediately thought of the legendary Death, the "taboo" in Xuanjun's mouth.

If it is defined by His time as "absolute now," then it is easy to understand. Wizards can try to change things that have already happened, but they are absolutely not allowed to step into the realm that even God has not yet touched.

"And Neville went back to November 26th," the Doctor said very seriously. "What we see on November 26th is that he just went back to the past, and then reappeared in 'now' immediately."

"I don't think there's anything wrong with this, maybe the effect of the spell is to return to the starting point of departure?" Harry said indifferently.

"You didn't notice Neville's expression, he didn't want to go back actively, but the natural effect of the spell," the Doctor pressed Harry's shoulder. "That is to say, the spell is not returning to the 'starting point of Neville's cognition', but returning to the 'true starting point', which is the anchor point he left in the river of time, but theoretically, he stayed here for half an hour, and he should appear half an hour after the crossing point when he goes back."

"In other words, when Neville went back to the past, time... paused," the Doctor made this astonishing guess.

"I think this is not hard to understand," Harry recalled his Muggle knowledge. "Neville's spell to travel through time is Hyper-Ascension, or understand it as Super-Ascension... In short, it is based on the Ascension Charm, and the Ascension Charm is a spell that accelerates people."

"Relativity believes that the closer the speed is to the speed of light, the slower the passage of time will be," Harry said. "In fact, the Neville of November 26th didn't completely return to the so-called 'now'. There was still a short interval from disappearing to reappearing. I think it might be because of the acceleration, which led to him staying in the past for half an hour, but in this 'half hour', 'absolute now' just passed a few seconds."

"I also went to Muggle university, Harry," the Doctor shook his head. "Relativity refers to the time of the mover. If you think Neville is accelerating, then it should be reversed. He spent half an hour in the past, and 'absolute now' might have to pass several days."

"You see, this is the opposite... oh, opposite!" The Doctor looked like he suddenly realized. "So that's it, I understand, he just reversed the polarity." ===== CHAPTER 136 =====