Deep within Stringlight Research Institute, a newly built teaching area named "Suyuan Hall" exuded an atmosphere distinctly different from the precision-tension of laboratories or the strategic gameplay of meeting rooms. Here the lighting was softer, walls used sound-absorbing materials, the environment quiet enough to hear the faint sound of central air conditioning, yet it seemed one could also hear the crackling sparks of countless young minds. The circular tiered classroom design abandoned the traditional layout of a high, dominant podium; its center was an interactive zone capable of holographic projection and freehand writing, with seats encircling it—symbolizing that knowledge exploration has no absolute center, everyone can be a contributor of thought. This was the main classroom of the "Interdisciplinary Ignition Class."
This special project, jointly initiated and led by Yue'er and Xiuxiu, had a simple yet profound original intention: globally select teenagers who displayed extraordinary talent and intense curiosity in fields like mathematics, physics, engineering, or computer science, not constrained by traditional exam scores, but emphasizing unique thinking, potential for interdisciplinary understanding, and that almost instinctive drive to explore. Gather them here, personally taught by Yue'er and Xiuxiu—two guides standing at the peaks of theory and technology respectively—not for cram-style knowledge indoctrination, but to ignite the inner flame within them, cultivate their ability to think and solve complex problems from perspectives that cross disciplinary boundaries, and shape the next generation of interdisciplinary leaders who can define the future.
Today was the first formal seminar of the Ignition Class. Seated below were thirty youths from diverse cultural backgrounds worldwide, aged between fifteen and eighteen. Their eyes were clear yet sharp, bearing edges not fully polished by the mundane world, and a near‑greedy craving for the unknown. Some of them might have already won gold medals in International Mathematical Olympiads, independently developed astonishing software or robots, or possessed insights into quantum mechanics or cosmology profound beyond their years. But now, sitting in this classroom, facing the two legendary figures about to appear, they still could not conceal excitement and a hint of nervousness.
Yue'er and Xiuxiu walked in side by side. They were not wearing formal attire symbolizing authority nor lab coats; Yue'er wore an elegant light‑gray knit sweater and trousers, Xiuxiu a crisp dark casual outfit. Their presence brought no sense of pressure; rather, they seemed like two erudite guides preparing to lead these young explorers into a new jungle of knowledge.
"Students, welcome to Suyuan Hall, welcome to the Ignition Class," Xiuxiu spoke first, her voice gentle yet firm, her gaze sweeping over the young faces as if seeing her own younger self—immersed in libraries, refusing to give up in labs. "Standing here, looking at you, what comes to mind is not merely the achievements and honors you've already earned, but that curiosity about how the world works, that light in your eyes wanting to create and change with your own hands."
She paused, letting the words sink in. "Teacher Yue'er and I, over the past ten‑plus years, have done some things. We've broken through barrier after barrier in lithography technology, we've tried to touch the underlying code of the mathematical universe. But we've come to realize ever more clearly that individual wisdom, the power of a single discipline, is far from sufficient when facing this world's truly complex, fundamental challenges. Breakthroughs in lithography machines require deep integration of optics, materials, physics, control, software, even mathematics; and the exploration of the PNP conjecture, of a unified theory, likewise demands stepping out of pure mathematics's framework, drawing inspiration from physics, information, even engineering practice."
Yue'er took over, her voice more serene, like deep‑pool water yet containing immense energy. "Knowledge originally is a whole. It is humans who, for cognitive convenience, artificially divided it into mathematics, physics, chemistry, biology, engineering… These boundaries, while helping us delve deeper, also build high walls hindering us from seeing the full picture. We established the Ignition Class hoping to work with you to try toppling these walls, or at least open enough doors and windows in them."
She didn't directly lecture on abstruse mathematics but posed a seemingly simple question: "Please think: what is an 'optimal path'?"
The question sparked lively responses. Some approached from graph theory discussing shortest‑path algorithms; others from physics thinking of light's principle of least time (Fermat's principle); yet others from biology mentioning ant pheromone trails; and some from economics discussing cost minimization.
Yue'er listened, nodding occasionally, then sketched in the interactive zone with a holographic pen. "Interesting, look," she drew while speaking, "In graph theory, the optimal path may be a discrete, combinatorial optimization problem; in physics, the path light takes is an extremum of some 'action,' a variational problem; in ant behavior, it reflects swarm intelligence and stochastic optimization… These seemingly different fields describe a similar concept. So, might there exist a more fundamental mathematical framework that can uniformly describe 'optimality' across these different contexts? This perhaps connects to the core of computational complexity (P vs. NP), and also to optimization phenomena ubiquitous in nature."
She skillfully guided a specific, perceivable problem toward deep, interdisciplinary mathematical thought. The youths listened intently; they discovered mathematics was no longer cold formulas in textbooks but a unified language for understanding various "optimal" phenomena in the world.
Then Xiuxiu demonstrated another facet. She played a high‑speed‑camera video: droplets falling on different super‑hydrophobic surfaces, bouncing, rolling, even merging and splitting, displaying all sorts of marvelous dynamics. "Students, observe these droplets' motions. This involves fluid mechanics, surface chemistry, material science. But if we want to design a surface that makes droplets move in a specific way—for example, roll along a trajectory we set, or merge precisely where needed—how should we proceed?"
She introduced the concept of "metasurface," showing how to manipulate light wavefronts by designing nanostructures, analogously proposing whether we could similarly control droplet trajectories by designing micron‑ or nano‑scale surface structures. "This requires linking macroscopic fluid behavior with microscopic surface structures, intermolecular forces. This is not only an engineering problem but a cross‑domain intersection of physics, chemistry, materials, even computational simulation. What we need are minds that not only understand fluid equations or material fabrication, but can comprehend how physical laws interact across scales from nanometers to millimeters, and can use computational tools to design and optimize such complex interactions."
Yue'er added timely: "This precisely echoes the 'optimal path' question. In designing such a surface, we are essentially searching for that 'optimal' point in a high‑dimensional space formed by countless structural parameters that achieves our preset droplet‑motion goal. This too is a complex optimization problem, perhaps approachable with some geometricized thinking, like we discussed earlier…"
The two teachers, one starting from abstract mathematical principles, the other from concrete engineering phenomena, naturally converged in the classroom, clearly showing the youths the profound, beautiful connective channel between theory and application. They didn't give standard answers but continuously raised questions, guided hypotheses, encouraged doubts, and demonstrated how different disciplinary perspectives offer unique insights into the same problem.
The latter part of the class was a free Q&A and discussion session. The youths' minds were exceptionally active, their questions ranging wildly yet hitting the core. One asked Yue'er: "Teacher, if P really does not equal NP, does that mean the universe essentially has some problems we cannot solve quickly? Is that a kind of computational 'fatalism'?" Another asked Xiuxiu: "Teacher, in carbon‑based chip R&D, is the biggest uncertainty from the material itself, or from the limitations of our manufacturing process? How do we distinguish technical bottlenecks from physical limits?"
Some questions even touched the frontiers Yue'er and Xiuxiu themselves were still exploring. They didn't evade but candidly shared their thoughts, encountered difficulties, and those unsolved mysteries. They told these young people that the borderlands of science are precisely defined by these unknowns; the joy and value of exploration lie right there. They weren't transmitting absolute truths but demonstrating an attitude and method toward the unknown—remain curious, dare to cross boundaries, verify rigorously, tolerate failure.
Looking at those young, focused faces, seeing the light flickering in their eyes from intellectual collision, a deep, warm flood of emotion welled up simultaneously in Yue'er's and Xiuxiu's hearts. They recalled their own youthful quests, that purest love for knowledge, that desire to understand and change the world. Now they stood at positions they once admired, possessing the capacity and resources to influence the world. But they deeply knew: personal achievements, however brilliant, would eventually fade with time. Only by passing on the torch of knowledge, the spirit of exploration, the interdisciplinary way of thinking—igniting more young minds—could the civilization's torch never extinguish, illuminating humanity's path toward a more distant future.
This was a higher‑order value realization, transcending personal honor, paper publications, technological breakthroughs. They saw themselves as one leg in civilization's relay race; after sprinting, their most important mission was to steadily, hopefully pass the torch in their hands to the next runner. Looking at these youths of boundless potential, they seemed to glimpse future mathematicians, engineers, cross‑domain pioneers perhaps even more outstanding than themselves. This expectation, this responsibility, gave them a sense of nearly eternal solace and strength.
Class ended, yet the youths still gathered around them, discussing fervently, unwilling to leave. Yue'er and Xiuxiu exchanged a smile, seeing the same sentiment and resolve in each other's eyes. The torches had been kindled; they would take root, sprout in these young hearts, and one day grow into towering trees, connecting a vaster sky. And they, as the ones who lit the torches, found the deepest continuation and sublimation of their life's meaning precisely in this act of passing. Knowledge's river flows unceasing precisely through such transmission and convergence, generation after generation, toward that boundless ocean of wisdom.