In the classroom corner, before an old bookshelf, Yuki found a book.
"A Mathematical Theory of Communication"
"That's Shannon's original paper," Aoi called from the side.
"Shannon... this person created information theory, right?"
"1948. A single paper gave birth to a new academic field."
Mira quietly approached and opened the book. Equations lined the pages.
"Beautiful," Mira whispered softly.
Yuki looked curiously. "Equations are beautiful?"
Aoi explained. "Shannon's theorem is simple yet powerful. H = -Σ p(x) log p(x). This single formula captures the essence of information."
At that moment, Professor S passed by.
"Talking about Shannon?"
"Professor!" Yuki was surprised.
"He was a genius. Communication, cryptography, game theory. He revolutionized everything."
The professor picked up the book.
"What Shannon proved was the existence of limits. You cannot send beyond channel capacity. But below capacity, you can send with almost no errors."
"That's both hope and constraint," Yuki said.
"Exactly. Same as physical laws. You cannot exceed light speed. But you can approach it."
Aoi supplemented. "Before Shannon, no one knew the limits. They tried blindly."
"After Shannon, the goal became clear," the professor continued. "How far we can go, what's impossible. He showed it mathematically."
Mira wrote in her notebook. "Theory gives direction"
"Theory gives direction," Aoi translated.
Yuki asked. "What kind of person was Shannon?"
The professor smiled. "He was playful, they say. Juggling while riding a unicycle, building machines to solve mazes."
"A genius who played?"
"There was no boundary between play and research. Curiosity drove everything."
Aoi was impressed. "That's why he could create such a universal theory."
"Entropy, information amount, communication capacity. These concepts Shannon defined remain unshaken today."
Yuki turned pages. Complex equations continued, but she felt she could see the intent behind them.
"Professor, what changes when you learn information theory?"
The professor pondered.
"Your view of the world changes. Everything appears as probability and information flow. Conversations, data, even the universe."
"The universe too?"
"Black hole information, quantum entanglement. Modern physics uses information theory too."
Mira pointed to another page. "Channel capacity theorem"
"The channel capacity theorem. Shannon's greatest achievement," Aoi said.
The professor looked outside the window.
"You're walking the path Shannon walked. Step by step, steadily."
Yuki closed the book.
"I feel like I'm walking with Shannon."
"His spirit lives on," the professor said. "Challenging limits with curiosity and playfulness. That's Shannon's legacy."
Aoi added. "Information theory is still developing. The journey Shannon began hasn't ended."
Mira smiled. It was rare.
"We walk with Shannon"
"We walk with Shannon," Yuki repeated.
The professor quietly left. The three remained before the bookshelf.
In the old paper, Shannon still smiles.
The journey of information continues. They are part of it.