A/N: I used part of the concept of time travel in the Philosophy of Time-Travel by Roberta Sparrow in Donnie Darko. I also used a theory of space-time continuum.
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Hermione and Flamel had been researching tirelessly for weeks. They usually started for the library so early in the morning that it was still dark outside and left around midnight. Both had taken to eating very little and to obsessively reading all the time.
So far they had out ruled several ideas. A Time-Turner had been determined inadequate, since Time-Turners were relatively new to that time period and hence weren't very advanced. Also, they were used mostly for going back hours in time, not going forward years. Potions and spells had also been ruled out, as neither could find any that would transport one forward in time.
One day, the silence in the library was broken by one word:
"Portal."
"Pardon?" said Hermione.
Flamel grinned. "A time portal would work."
"Okay, you guys have just barely figured out Time-Turners. How in Merlin's name do you expect to make a time portal?"
"I am thinking that we could use the charm to make portkeys-"
"You have portkeys?"
"-and use it to to transport you to a different time instead of a different place."
Hermione was skeptical. "But that would take ages to figure out."
But Flamel ignored her and stood abruptly, making the girl jump in surprise. His eyes were glowing with excitement as he practically yelled "I'll be right back!" before turning and fleeing out of the library. Several nearby students stared at him before glancing at Hermione and turning away.
Mere seconds later he reappeared carrying a huge ancient runes book and a book about Muggle physics. He dropped them with a thud on the table and flipped open the physics book to show her two pictures. One was a flat coordinate system, the other was a wavy coordinate system.
"This," Flamel pointed to the picture of the flat coordinate system, "is the third dimension, the one in which we are in now. This other one," he pointed to the wavy system, "is the fourth dimension, which we can use to transport you years into the future. I can't believe I didn't think of it before! It's not exactly a time portal, now that I think about it- more like a time machine, really."
Hermione was looking at him as if he were mad, but the old wizard took no notice.
"Look, in our dimension we have longitude, latitude, and altitude. In the fourth dimension we have those three plus our perception of the passage of time." He made several seemingly random dots on both systems. "What we need to do is find a way to connect the points on the third dimension to the points on the fourth dimension."
"Okay," said Hermione, as if she understood. "How would we do that?"
"We would find the curvature of space-time between the two sets of points. We could use ancient runes for that. Once we find that, we'll be able to measure space-time and possibly build something that will be able to fold space-time, hence sending your forward in time."
"Umm...what's space-time?"
"Simple. Time and space existing together as one thing."
"Oh." Hermione felt immensely stupid.
Flamel resumed talking. "Of course, we'll need to make a vessel to send you off in. Which means we'll need an incantation to make it able to go through space-time...what year are you from?"
"Two thousand and six."
"Excellent. How about 'Portus ut annus duos mille quod semestris'?"
"Sure. What does it mean?"
"It's Latin. 'Transport to year 2006.' Simple enough."
"Yes, very simple." Said Hermione. Flamel didin't seem to catch onto her sarcasm, as he started talking again.
"I'll work on the mathematics part of it. You go find a vessel in which to transport yourself. Make it metal."
So Hermione wandered off, hardly believing that they were about to make a time-machine that would take her home.
