'Pearl' 3 of 3.
The world resolved into a choking cloud of dust and the sharp, acrid smell of burning timbers. Pearl Wu coughed, a wracking, painful sound that scraped his raw throat. He pushed a piece of plaster off his chest, the dull ache a counterpoint to the frantic thumping of his own heart. Above him, a jagged hole gaped in the ceiling, revealing a sky stained the bruised and angry colour of a dying fire. The house, or what was left of it, groaned around him, a wounded beast settling into its final, agonizing moments.
He had been in the study, poring over a pre-war census of London's East End, fascinated by the demographic shifts, the subtle patterns of segregation that were already taking shape long before the bombs began to fall. The academic paper he’d been reading, a multiscalar analysis of segregation in North-Western Europe from a future he could no longer be certain of reaching, had spoken of residential segregation as a “spatial separation of groups of people”. He’d been tracing the lines of ethnicity and class, the invisible walls that divided communities, when the air raid siren had wailed its mournful song. He’d barely had time to dive under the heavy oak desk before the world exploded. Now, a profound silence, punctuated only by the crackle of nearby flames and the distant, almost serene, drone of the bombers heading back east.
He scrambled out from under the desk, his body a symphony of aches and bruises. Dust coated him, a fine white powder that turned his black hair grey and clung to his eyelashes. He was a ghost, a phantom of plaster and fear. Outside, the street was a scene from Dante’s Inferno. Buildings stood as skeletal remains, their innards spilling out onto the pavement. Fires raged, casting flickering, demonic shadows that danced and writhed in the gloom. The air was thick with the dust of pulverized brick and the metallic tang of blood. He stumbled through the debris, his mind a whirlwind of shock and disorientation. He knew the statistics of the Blitz, the tonnage of bombs dropped, the number of homes destroyed, the estimated casualties. But to see it, to be in it, was a different calculus altogether.
It was then that he saw them. Two British soldiers, their faces smudged with soot, their rifles held at the ready. They spotted him at the same time.
“Oi, you there! Stop right where you are!” one of them shouted.
Pearl froze, raising his hands slowly.
“Who are you? What are you doing out here?” the first soldier demanded.
“My name is Pearl Wou,” he said, his voice hoarse. “My house…it collapsed.”
The second soldier shone a torch in his face. “Wou? That’s not an English name, is it?”
“No. I am from Hong Kong.”
The soldiers exchanged a look. “A Chink, eh?” the taller one said. “Let’s see your papers.”
Pearl’s heart sank. His meticulously forged identity documents were in his jacket, buried under tons of rubble. He had only his wallet, with twenty pounds and nothing else. “I…I don’t have them. They were in my jacket.”
“Convenient,” the stocky soldier grunted. “A man with no papers, wandering about during a raid. Looks a bit fishy, don’t you think, Sergeant?”
The Sergeant nodded. “Could be a spy. Or a looter.”
They marched him to a makeshift command post in the basement of a church. A harried-looking officer listened to their report. “No papers, you say? We can’t hold him here. Put him on the next train to Paris. The French can deal with him.”
And so, Pearl, a time-traveler from the future, became an undocumented alien in the war-torn past, deported from a city under siege to a city under occupation.
Paris was a city of subdued elegance. The grand boulevards remained, but a shadow hung over them. Swastikas adorned public buildings, and the grey-green uniforms of the Wehrmacht were a constant presence. Here, his Cantonese and English were useless. He survived on rudimentary French, sleeping in a park, the cold seeping into his bones.
On his third day, he was stopped by two German officers.
“Papiere, bitte,” one said. -Papers, please.-
“Je suis désolé, monsieur. Je n'ai pas de papiers. Ma maison a été détruite dans un bombardement à Londres.” -I am sorry, sir. I have no papers. My house was destroyed in a bombing in London.-
The officer switched to German. “Ein Engländer?” -An Englishman?-
“Nein. Ich komme aus Hongkong.” -No. I am from Hong Kong.-
The questions became more aggressive. The word Jude -Jew- was mentioned more than once. Pearl, with his dark hair and non-European features, was an object of suspicion. He knew of the deportations, the camps, the systematic rounding up of anyone deemed undesirable. Nazi ideology viewed Jews not as a religious group, but as a dangerous "race". He had studied the horrific statistics of the Holocaust, the six million European Jews murdered, a number that defied comprehension. Now, he felt a sliver of the terror that so many had faced. He knew that the Nazis' racial animosity extended beyond the Jews. They targeted other groups for persecution, including people with disabilities, Poles, Soviet prisoners of war, and Black people in Germany. He knew, with a certainty that chilled him to the bone, that a wrong answer could be a death sentence.
They took him to a holding cell, a cold, damp place that smelled of despair. He was interrogated repeatedly. His anomalous status, however, was his salvation. They didn’t know what to do with him. He wasn't English, he wasn't French, he wasn't a Jew. He was a statistical outlier, a problem they couldn't neatly categorize. After three days, they let him go, with a temporary pass identifying him as a stateless person.
He found a room in a cheap boarding house and began to explore the city, not as a tourist, but as a mathematician studying the brutal calculus of occupation. He saw the queues for bread, the ration cards, the faces of hunger. He saw the fear in people’s eyes. But he also saw moments of defiance: a graffitied V for Victory, a whispered joke, a look of shared contempt.
He spent his days in libraries, poring over economic data. He tracked the inflation rate, the decline in wages, the rise in infant mortality. He was a time-traveler, a man with the benefit of hindsight, and a witness. He analyzed the racial dynamics of the city with a keen eye. He saw how the Germans had imposed their twisted racial hierarchy. The Nazis believed that “superior races had not just the right but the obligation to subdue and even exterminate inferior ones”. He saw the posters demonizing the Jews, the yellow stars they were forced to wear, the gradual, systematic process of their exclusion from public life. He saw the segregation, not just of Jews, but of anyone who didn't fit the Aryan ideal.
He began to write, not a research paper, but a chronicle. He wrote about economic theories and how they applied to the distorted economy of an occupied city. He wrote about the psychological effects of marginalization, using probability to model the long-term effects of the war. He wrote about his own fear, his own sense of dislocation.
One evening, he saw German soldiers harassing a young Jewish woman, tearing the yellow star from her coat. He watched from the shadows, his heart pounding. He was one man, unarmed. To act would be to invite his own destruction. He stood a silent, helpless witness, as the soldiers moved on, leaving the woman sobbing. He was a time-traveler, a man with a god-like perspective on history, but in that moment, he felt utterly, hopelessly human. He was a part of the equation, a variable in the calculus of suffering. And he knew, with a certainty that chilled him to the soul, that the numbers, the data, the theories, could never truly capture the horror of what he had seen. They could only bear witness to it, in their own cold, silent way. And that, he decided, would have to be enough. For now.
Hong Kong, 2025. The city was a relentless assault on the senses, a chaotic symphony of neon and noise that had once felt like home. Now, it was just noise. The cheerful cacophony of Cantonese street vendors, the rumble of the MTR, the incessant chatter of a million lives lived in close proximity – it all grated on Pearl’s frayed nerves. He had returned from the Blitz and the hedgerows of Normandy to a world that was supposed to be his, but the ghost of the past clung to him like the fine, white dust of a collapsed building.
He sat at his desk, the skyline of Hong Kong a glittering, indifferent backdrop. His apartment, once a sanctuary, now felt like a cage. The books on his shelves, the scientific papers neatly stacked, the half-finished models of atomic structures – they were all relics of a former life, a life before he had seen history’s bloody, brutal underbelly. He stared at the blank page on his computer screen, the cursor blinking, a mocking metronome counting out the seconds of his inadequacy.
The paper was supposed to be his magnum opus, a groundbreaking work on the mathematics of war. He had the data, the firsthand experience, the statistical models. He had witnessed the Blitz, crossed the Channel with the Americans, and felt the hot sting of shrapnel on D-Day. He had seen the fear, the courage, the mindless slaughter. But the central thesis, the unifying theory, remained elusive. He wanted to do more than just describe the impact of war on society; he wanted to solve the equation, to find a way to predict conflict, to prevent it. But how do you model the irrationality of human hatred, the complex interplay of politics, economics, and ideology that led to war? How do you quantify the unquantifiable?
He had tried to explain it to Leyue, to bridge the chasm that had opened between them. But the words always failed him. How could he make her understand the smell of cordite, the screams of the wounded, the hollow-eyed stare of a man who had seen too much? He had shown her the scars on his chest, the angry red welts that were a remarkable medallion of his journey, but they were just a physical manifestation of a much deeper wound, a wound that refused to heal.
They had gone for a walk along the Tsim Sha Tsui promenade, the city lights painting a shimmering, illusory beauty on the water.
“你瘦了,” she had said, her voice soft. -You’re thinner.-
“It was a…difficult time,” he had replied, his Cantonese rusty, a foreign language in his own mouth.
They had stood in silence, the chasm between them as wide and deep as the harbour. He wanted to tell her everything, to unburden himself of the memories that haunted his waking hours and stalked his dreams. But he couldn't. He couldn’t bring the war home with him. He couldn’t infect her with its poison.
The city around him was a constant, jarring reminder of how much had changed, both in him and in Hong Kong. The vibrant, chaotic, and defiantly independent city he had left behind was gone, replaced by a place that was more subdued, more cautious. The 2020 National Security Law had cast a long shadow, and the "patriots-only" electoral reforms had silenced the once-vibrant pro-democracy movement.[1][2] The press, once a bastion of free speech, was now a shadow of its former self, with journalists engaging in self-censorship to avoid the uncertain red lines of the new laws.[3] It was a different kind of war, a silent, insidious one, but a war nonetheless.
He turned back to his computer, the cursor still blinking, a relentless, mocking rhythm. He thought of the soldiers he had met, the ordinary men caught up in extraordinary circumstances. He thought of the civilians, their lives shattered by a conflict they had not chosen. And he thought of Leyue, her face a mixture of love and confusion, her eyes pleading with him to come back to her.
He began to type, not the formal, academic language he was used to, but something more raw, more personal. He wrote about the long-term psychological effects of war, the post-traumatic stress that lingered long after the physical wounds had healed.[4][5] He wrote about the displacement, the disrupted families, the increased violence and crime that were the inevitable aftermath of conflict.[6] And he wrote about the difficulty of predicting war, the complex interplay of factors that could lead a nation to the brink of self-destruction.[7][8][9][10]
He knew he didn’t have the answer yet. He knew that the problem was far too complex for any single theory, any single equation. But as he wrote, he felt a flicker of something he hadn’t felt in a long time: hope. He had seen the worst of humanity, but he had also seen its best. He had seen courage and sacrifice, love and resilience. And it was in that resilience, in the unbreakable spirit of the human heart, that he believed the answer lay. He would find it. He had to. For himself, for Leyue, and for the countless others who had been touched by the long, dark shadow of war. He would find a way to solve the equation, to predict the unpredictable, and, perhaps, to prevent the preventable. The war had taken so much from him, but it had also given him a purpose. And in the quiet of his Hong Kong apartment, surrounded by the ghosts of the past and the uncertainties of the future, he began to work.
The churning grey water of the English Channel was a liquid manifestation of Pearl’s stomach. He leaned over the side of the landing craft, the salty spray mingling with the sour taste of bile in his mouth. Around him, the other soldiers were in a similar state, their faces a pasty green, their youthful bravado washed away by the relentless motion of the sea. The sheer scale of the flotilla was staggering. The D-Day armada consisted of 6,000 ships and landing craft, a floating city of steel and men, all pointed at the hazy coastline of Normandy. It was, he knew, the largest naval, air, and land operation in history.
He clutched the cold, wet railing, his knuckles white. In his mind, he was running the numbers, a habit he couldn't break even in the face of such overwhelming, visceral reality. He had pored over the intelligence reports, the weather forecasts, the estimates of German defenses. General Eisenhower had delayed the invasion by 24 hours due to bad weather, a decision that had hung on the fragile thread of a meteorologist's prediction. A single variable, a low-pressure system in the Atlantic, could have unraveled the entire, intricate equation.
He thought about the probability of success. The Allies had amassed a force of over 150,000 men from the United States, the United Kingdom, Canada, Free France, and Norway. They had air superiority, with 11,000 planes ready to pound the German positions. They had the element of surprise, thanks to a massive deception campaign that had convinced the Germans that the main attack would come at Pas-de-Calais. But war was not a neat mathematical problem. It was a chaotic, unpredictable storm of variables, of human error, of blind luck. The Germans, for their part, suffered from confusion in their ranks and the absence of their celebrated commander, Erwin Rommel, who was on leave. Hitler himself, believing the invasion was a feint, refused to release nearby divisions to join the counterattack.
A young private from Ohio, his face barely old enough to sprout a decent beard, vomited over the side. Pearl, the time-traveling mathematician from Hong Kong, felt a surge of empathy for the boy. They were all just numbers in a grand, terrible equation, their lives reduced to a statistical probability of survival.
The coastline grew larger, a dark, menacing line on the horizon. The drone of the bombers grew louder, a sound that was both terrifying and reassuring. The beaches had been given code names: Utah, Omaha, Gold, Juno, and Sword. Omaha, he knew, would be the costliest in terms of Allied casualties.
The ramp of the landing craft slammed down, and the world erupted in a symphony of chaos. The air was thick with the shriek of bullets, the roar of explosions, and the screams of men. Pearl charged forward, his rifle held tight against his shoulder. He was no soldier, but he knew how to follow orders. He ran through the churning surf, the cold water a shocking jolt to his system. He saw men fall around him, their bodies crumpling like discarded dolls. He saw the water turn red.
He made it to the beach, the sand a treacherous, shifting landscape of craters and bodies. He took cover behind a shattered concrete barrier, his heart pounding a frantic, irregular rhythm against his ribs. He fired his rifle, the recoil a jarring shock to his shoulder. He didn’t know if he hit anyone. He just pointed and fired, another variable in the chaotic equation of battle.
He saw a young black soldier, a member of a segregated engineering battalion, charge forward, a Bangalore torpedo in his hands. He was a part of the "Red Ball Express," the logistical backbone of the Allied army, but he was also a frontline soldier, fighting and dying for a country that treated him as a second-class citizen. Pearl had seen the racism firsthand, the casual slurs, the segregated barracks, the invisible lines that divided the Allied forces. It was a hypocrisy that gnawed at him, a stain on the very idea of a war fought for freedom.
A shell exploded nearby, and a searing pain shot through his leg. He looked down and saw a jagged piece of shrapnel protruding from his thigh. The world began to spin, the sounds of battle fading into a dull roar. He had been injured, just as he had been programmed to be. His mission was complete. He had witnessed D-Day, the turning point of the war in Europe. He had seen the courage and the carnage, the triumph and the tragedy.
As the medics carried him back to the landing craft, he looked back at the beach. The battle was still raging, a chaotic, brutal ballet of life and death. The Allies had secured a foothold, but the cost was immense. More than 4,000 Allied troops had lost their lives on D-Day, with thousands more wounded or missing. By June 11, over 326,000 Allied troops would cross the channel, along with more than 100,000 tons of military equipment. The invasion would ultimately succeed, leading to the liberation of Paris on August 25 and the surrender of Germany on May 8, 1945. But for the men on the beach, for the men who had fallen, the statistics were meaningless. All that mattered was the sand, the sea, and the blood.
As the landing craft pulled away from the shore, Pearl closed his eyes. The pain in his leg was a dull, throbbing ache, but the pain in his heart was far worse. He had come to the past to understand war, to quantify it, to find a way to prevent it. But as he head back to his own time, he knew that some things could never be fully understood, never be fully quantified. Some things could only be witnessed, and mourned. The D in D-Day stood for "day," a simple, innocuous word for a day that had changed the course of history, a day that would be forever etched in the memory of the world, a day that he would never forget.
The transition was always jarring, a violent tearing of the self from one reality to another. One moment, the cacophony of Omaha Beach—the roar of artillery, the screams of the dying—the next, the sterile, humming silence of his apartment in the year 2025. Pearl collapsed onto the polished floorboards, the ghost of the landing craft’s rocking motion still swaying within him. The pain, a sharp, insistent fire in his thigh, was the only constant between the two worlds. It was real. The shrapnel was real.
He crawled to his medical kit, his movements clumsy, his body slick with a mixture of seawater, blood, and the cold sweat of temporal displacement. He fumbled for his phone, his thumb smearing the screen with grime.
“阿良,” he gasped when his friend picked up. -Ah-Leung.- “我需要你。好緊急。” -I need you. It’s urgent.-
An hour later, Dr. Michael Leung, his oldest friend and one of the few people who knew the true nature of his “research trips,” was kneeling on his floor, his face a mask of professional calm that did little to hide the alarm in his eyes. The living room had been transformed into a makeshift operating theatre. Sterilized instruments lay neatly on a clean white towel. The air smelled of antiseptic.
“You know, when you said you were getting into ‘field research,’ I pictured you in a dusty library, not…this,” Leung said, his hands deftly probing the wound. “This is a piece of an S-mine, a Bouncing Betty. Nasty bit of business. You’re lucky it didn’t take your leg off.”
“好彩,” Pearl breathed, gritting his teeth as Leung worked. -Lucky.-
The extraction was a brutal, intimate affair. Pearl watched, detached, as Leung pulled the jagged piece of German steel from his flesh. He was a mathematician observing a data point, a single casualty in a war that had claimed millions. What were the odds? He’d calculated them on the boat, a way of distracting himself from the nausea and the fear. An Allied soldier on D-Day had about a 97.6% chance of surviving the day.[1] Not bad, unless you were in the 2.4% that didn't. And those odds changed dramatically depending on your landing zone. On Omaha, in the first wave, the casualty rate for some units was as high as 66% in the first fifteen minutes.[2] A coin toss, with your life as the stakes.
He thought of the sheer number of deaths in the war, a number that defied easy comprehension. Estimates ranged from 70 to 85 million people, about 3% of the world's population in 1940.[3] Military deaths were between 21 and 25 million.[3] Civilian deaths were even higher, a staggering 50 to 55 million.[3] A torrent of death that had swept across the globe, a statistical hurricane that had reshaped the world.
“There,” Leung said, stitching the wound with neat, precise movements. “You’ll need to stay off it for a week. And you’ll need antibiotics. No more gallivanting through time until you’re healed, okay?”
The week of rest was a strange, suspended time. Leyue moved in, her presence a quiet, comforting constant in the chaotic landscape of his mind. She tended to him with a gentle efficiency, her touch a soothing balm on his fevered skin. But there was a distance between them, a chasm of unspoken words and unshared experiences.
“Does it…hurt?” she asked one evening, tracing the line of the stitches with her finger.
“Not so much now,” he said, his English feeling clumsy and inadequate.
“You are…far away,” she said, her own English hesitant, a language she was still learning. “Your mind is not here.”
She was right. His mind was in Normandy, in the hedgerows and the fields, in the faces of the men he had seen fall. He was haunted by the numbers, the cold, hard statistics of death. The Soviet Union had lost 27 million people, 8.7 million of them soldiers.[4] Poland had lost 20% of its pre-war population.[5] How did you even begin to calculate the impact of such a loss? It wasn’t just the deaths. It was the shattered families, the orphaned children, the generations that would never be born.
He tried to explain his work to her, the paper that was supposed to be the culmination of his life’s ambition.
“I want to find a way to predict war,” he said, looking out at the city lights. “To create a model that can identify the warning signs, the tipping points, the moments when a conflict becomes inevitable.”
“But how?” she asked. “War is…it is not math.”
“No,” he said, “but it is a system. A complex, chaotic system, but a system nonetheless. And all systems have rules, patterns, variables. If I can understand the variables, if I can model the patterns, then maybe…maybe I can find a way to change the outcome.”
He spent his days in a fever of calculation, his computer screen a blur of equations and charts. He modeled the economic factors, the political ideologies, the social tensions that had led to the war. He traced the rise of nationalism, the poison of racism, the seductive, deadly logic of fascism. But there was a piece missing, a variable he couldn’t account for.
As his leg healed, a new sense of urgency began to grow within him. He had one last mission, one final journey into the past. He needed to witness the very end, the final, apocalyptic moments of the war in Europe. He needed to see Berlin in 1945, to stand in the ruins of the Reichstag, to understand the endgame of a conflict that had consumed the world.
He stood up, testing his weight on his injured leg. It was still weak, but it would hold. He looked at Leyue, her face etched with a mixture of love and fear.
“I have to go back,” he said, his voice quiet but firm. “One last time.”
She didn’t try to stop him. She knew that he was a man possessed, a man on a mission that he could not abandon. She simply nodded, her eyes shining with unshed tears.
“小心啲,” she whispered. -Be careful.-
He kissed her, a long, lingering kiss that was both a promise and a farewell. Then he walked to the closet and took out the belt, the strange, otherworldly device that was both his greatest creation and his heaviest burden. He looked at himself in the mirror, a skinny, scarred man with the weight of history on his shoulders. He was a mathematician, a man of logic and reason, but he had seen firsthand that war was anything but logical. It was a force of nature, a storm of human passion and folly. And he was about to walk into the heart of it, one last time. He had the data, the models, the firsthand experience. But he was no longer sure if he was the one in control, or if he was just another variable in an equation he could never hope to solve. He took a deep breath, and with a flick of a switch, he dissolved into a shower of light, leaving the quiet of his Hong-Kong apartment for the chaos of a dying empire. The final variable in his grand equation awaited him.
The air in Paris on August 25, 1944, tasted of champagne and gunpowder. Hong, known to Pearl as Hua Xing, breathed it in, a strange, intoxicating cocktail that made her head swim with a mixture of joy and profound sobriety. She had arrived, courtesy of Pearl’s volatile temporal technology, a day after the first French and American tanks had rolled into the city, ending a German occupation that had lasted 1,533 days.[1][2][3] The streets were a living, breathing organism of pure, unadulterated ecstasy. People danced on the cobblestones, strangers kissed with tear-streaked faces, and French tricolor flags, stitched together from bedsheets, hung from every window, defiant symbols of a long-suppressed identity.[4]
Her French was a clumsy, patchwork thing, but it didn’t matter. Every Parisian she met, from the old woman who pressed a piece of hoarded chocolate into her hand to the young student who insisted on refilling her glass with cheap, sharp wine, was endlessly patient. They were not just celebrating a military victory; they were celebrating the return of their own voices.
“Vous n’êtes pas d’ici?” a man with a fierce moustache and kind eyes asked her. -You are not from here?-
“Non,” Hong replied, choosing her words carefully. “Je viens… d’un endroit très loin.” -No. I come from… a very distant place.-
He smiled, understanding everything and nothing at all. “N’importe. Aujourd’hui, nous sommes tous Parisiens.” -It doesn’t matter. Today, we are all Parisians.-
As she walked, the joyous scenes were juxtaposed with the fresh scars of battle. Bullet holes pockmarked the facades of elegant Haussmann-era buildings.[4] A burned-out German truck sat listing to one side, a modern sculpture of defeat. The city was free, but it was also wounded. For four years, Paris had been a city of shadows and scarcity.[1][5] A 9 p.m. curfew had plunged the City of Light into darkness every night.[6] Food, clothing, and coal were ruthlessly rationed, with the best of everything diverted to the German war effort, forcing Parisians into endless queues for grams of bread or meat.[5][7] The German occupiers had extracted a staggering economic price, demanding "occupation costs" that by 1943 were equivalent to over half of France's entire economic output.[7][8] It was a systematic plunder that crippled the nation.
Hong thought of the chilling accounts Pearl had shared of his time in this occupied city. Life was a constant struggle for the average citizen, but for minorities, it was a living hell. She looked at the crowds and wondered how many of them had been complicit, how many had resisted. The persecution had been methodical. In 1942, Jews were ordered to wear the yellow star badge.[5][9] They were barred from parks, cinemas, and cafés, and relegated to the last car on the metro.[6] French police had assisted in the horrific Vel d'Hiv Roundup, where over 13,000 Jews, including more than 4,000 children, were imprisoned in a sports stadium before being sent to transit camps like Drancy, and then on to the death camps.[9][10] Out of a population of approximately 340,000 Jews living in France in 1940, over 75,000 were deported and murdered.[10][11] Survival itself had been an act of resistance.
Her gaze fell upon a partially collapsed apartment building near the Hôtel de Ville, its interior exposed to the sky. The celebration faded into a low hum as her mind, analytical and precise, began to work. She saw not just rubble, but a complex problem in applied mathematics. The rebuilding of Paris, of London, of all of Europe, would be a task of unimaginable scale.
She thought in terms of calculus. To save a building like this, an engineer couldn’t just patch the holes. They would have to model the new stresses, the redistribution of weight. They would use differential equations to analyze the forces acting on the remaining beams and columns, to understand the very integrity of the structure under new, unfamiliar loads.[12][13] Integral calculus would be needed to determine the volume of new material required, to calculate the area of the curved surfaces of a damaged archway, to ensure the new form was not just aesthetically pleasing but structurally sound.[13][14]
It was an optimization problem on a grand scale. For every building, a decision had to be made: repair or demolish? The function to be solved had to minimize cost and the quantity of scarce materials, while maximizing structural safety and, where possible, preserving historical value.[12] The cost would be astronomical. Hong knew from Pearl’s future data that the Marshall Plan, the American initiative to rebuild Western Europe, would provide over $15 billion in aid, with France receiving the second-largest share after Great Britain.[15][16] It was an enormous sum, yet it was just a fraction of what would be needed. Rebuilding Germany alone was estimated to cost around $60 billion in 1950s dollars.[17]
The economic occupation had bled France dry, and the recovery would be a long, slow integration of variables over time. It would take years, even with aid like the Monnet Plan to modernize French industry and massive foreign loans, for the economy to regain its pre-war levels.[18][19][20] The economic devastation, the invisible wound of the war, would affect French commerce and society for at least a decade, influencing everything from housing to the labor market, which would see a large influx of immigrant workers to keep costs down.[21]
A group of celebrating students jostled past her, pulling her from her thoughts. They offered her a bottle of wine, their faces alight with the sheer, unthinking joy of the moment. She smiled and took a sip. For them, today was the end of a long nightmare. For Hong, armed with the terrible foresight of a time traveler, it was the beginning of an equally monumental challenge. The war had been won with bullets and blood, but the peace, she understood, would be won with concrete and calculus, with loans and labor, with the slow, patient, and incredibly expensive work of rebuilding a shattered world.
The air in Poland, even miles from Oświęcim, felt different in the winter of 1944. It was thin and sharp, and carried on it a faint, almost imperceptible odor of burning that clung to the back of the throat. Pearl materialized in a stand of skeletal birch trees, the world leached of color, a stark palette of white snow, black branches, and a sky the color of old iron. The silence here was a different kind of silence than the one he'd known in his quiet Hong Kong apartment. It was a heavy, suffocating silence, a silence that had absorbed so many screams it had forgotten how to be anything else. He was dressed in the threadbare clothes of a Polish peasant, his forged papers identifying him as Jan Kowalski, a deaf-mute farmhand. It was a disguise born of a grim necessity he hadn't fully appreciated until he saw the smoke.
It rose in the distance, a thick, greasy column that stained the grey sky. It was not the smoke of a hearth or a factory. It was the smoke of a funeral pyre on an industrial scale. He walked towards it, his heart a cold, heavy stone in his chest. He had studied the blueprints, the aerial reconnaissance photos from the future. He knew the layout of Auschwitz-Birkenau, the precise geometry of its horror. But to see it, to smell it, was to understand the obscene inadequacy of data in the face of such a monstrous truth.
He found a position on a small hill overlooking the camp, a vantage point that gave him a clear, unobstructed view of the sprawling complex of barracks, fences, and guard towers. It was a city of death, laid out with the cold, brutal efficiency of a mathematical proof. He saw the trains arriving, cattle cars packed with human beings, their faces a blur of confusion and fear. He saw the columns of people, the old, the young, the sick, the healthy, being marched towards the gas chambers. He saw the Sonderkommando, the Jewish prisoners forced to work in the crematoria, their faces hollowed out by a grief that was beyond human comprehension.
His mind, a refuge of logic and reason, reeled. He tried to retreat into the numbers, to find some solace in the cold, hard certainty of statistics. The Holocaust, the systematic, state-sponsored persecution and murder of six million Jews by the Nazi regime and its collaborators. It was a number so large it was almost meaningless. How do you comprehend six million? It was the entire population of Hong Kong, erased from existence. He thought of the death tolls from the war, the 8.7 million Soviet soldiers, the 20% of Poland's pre-war population. They were all staggering numbers, but there was a difference. The soldiers had been killed in combat, the Polish civilians in the crossfire of a brutal occupation. But this…this was different. This was a factory of death, a production line of murder, a calculated, deliberate, and remorseless extermination of an entire people.
The Nazis had targeted not just Jews, but other groups they deemed racially or ideologically inferior. Slavs, Roma, Jehovah's Witnesses, homosexuals, the disabled—they were all fed into the maw of the Nazi killing machine. But the Jews were the primary target, the "priority enemy," in the twisted logic of Nazi racial ideology. He thought of the camps, a network of death that stretched across Europe. Auschwitz, where over a million people were murdered. Treblinka, where the number was close to 900,000. Belzec, Sobibor, Chelmno, Majdanek—each one a name that would be forever synonymous with the darkest chapter in human history.
But as he watched the smoke rise, a terrible question began to form in his mind. What was the probability that the Nazis would have been caught before the war ended? Why hadn't the world intervened? He had access to the historical data, the declassified intelligence reports, the memoirs of the men who had made the decisions. The information had been there. The Polish government-in-exile had reported on the extermination of the Jews as early as 1942. The Allies had photographic evidence of the camps. But they had not acted.
Why?
It was a complex equation, a multivariate problem with no easy solution.
First, there was the problem of confirmation. The reports were so horrific, so beyond the pale of human experience, that they were difficult to believe. In a world saturated with propaganda, it was hard to separate the signal from the noise. The Nazis, masters of deception, had gone to great lengths to conceal their crimes, to present the camps as nothing more than transit centers for resettlement. The probability of a false positive—of acting on faulty intelligence and diverting resources from the war effort—was a significant factor in the Allied calculation.
Second, there was the cold, hard logic of strategic priorities. The Allies were fighting a war for their very survival. Their primary objective was the unconditional surrender of the Axis powers. Every bomber, every soldier, every ton of supplies was a precious resource that had to be allocated with a ruthless, mathematical precision. The argument was that the most effective way to save the Jews was to win the war as quickly as possible. To divert resources to bombing the camps or the railway lines leading to them would be to prolong the war and, paradoxically, to cost more lives in the long run. It was a grim, utilitarian calculus, a real-life trolley problem with millions of lives in the balance.
Third, there was the uncomfortable, undiscussed variable of antisemitism. It was not a uniquely German phenomenon. It was a poison that had seeped into the very foundations of Western civilization, a prejudice that was as old as Christianity itself. From the blood libels of the Middle Ages to the pogroms of Tsarist Russia, the Jews had been the perennial scapegoat, the "other" against whom the dominant culture defined itself. The Allies, for all their talk of fighting for freedom and democracy, were not immune to this ancient hatred. The thought that some of the inaction might be attributed to a subconscious, or even conscious, devaluation of Jewish lives was a chilling, and not entirely improbable, hypothesis.
His mind, seeking a larger context, a way to make sense of the incomprehensible, began to compare the Holocaust to other dark chapters in human history. The Armenian Genocide, the systematic extermination of 1.5 million Armenians by the Ottoman Empire during World War I. The Holodomor, the man-made famine in Soviet Ukraine that had killed millions. The Cambodian Killing Fields, where the Khmer Rouge had murdered a quarter of their own population. The Rwandan Genocide, the slaughter of 800,000 Tutsis in 100 days. The atrocities committed by King Leopold II in the Congo Free State, where millions had died in the brutal pursuit of rubber and ivory.
He saw the common variables, the recurring patterns in the mathematics of mass murder. The dehumanization of the victims, the use of propaganda to whip up hatred and fear, the creation of a bureaucratic machinery of death, the complicity of ordinary people who were willing to look the other way. The Holocaust was not an anomaly, a singular, inexplicable event. It was the apotheosis of a dark and recurring pattern in human history, a pattern that was as predictable as it was horrifying.
He could model it, he realized with a sickening sense of clarity. He could create an equation for genocide, a probabilistic model that could identify the warning signs, the preconditions, the tipping points. The variables would include economic instability, political polarization, the rise of charismatic, authoritarian leaders, the spread of extremist ideologies, the demonization of a minority group. It would be a complex, non-linear equation, a chaotic system with multiple feedback loops. But it could be done.
The thought brought him no comfort. To understand a thing is not to control it. To predict a storm is not to stop it. He had come to the past to find a way to prevent war, to solve the equation of human conflict. But as he stood on that frozen hill in Poland, the smoke of Auschwitz burning his eyes and searing his soul, he realized the terrible, heartbreaking truth. The problem was not in the math. The problem was in the human heart, in its infinite capacity for both love and hatred, for compassion and cruelty. And that was a variable that he could never hope to quantify.
A sudden shout from below broke his reverie. A German patrol was making its way up the hill. He turned and ran, his leg, not yet fully healed from the D-Day shrapnel, screaming in protest. He ran through the birch trees, the branches clawing at his face like the hands of the dead. He ran until his lungs burned and his vision blurred. He ran until the smell of the smoke was just a memory, a stain on the winter air. But he knew, with a certainty that was as cold and hard as the frozen ground beneath his feet, that he would never be able to run far enough. The numbers would always be there, a silent, damning memory of what he had seen. Six million. It was a number that would haunt him for the rest of his life, a number that he would carry with him, a ghost in the machine of time, a constant, terrible reminder of the day he had stood on a hill and witnessed the world’s descent into madness.
The salt-laced fog of San Francisco was a soft, grey blanket, muffling the city in a gentle, introspective silence. It was a world away from the razor-sharp, smoke-tainted air of 1944. Pearl stood on the steps of City Hall, the grand Beaux-Arts dome disappearing into the low-hanging clouds above. He felt a tremor in his hand and reached for Leyue’s, her fingers intertwining with his, a warm, steady anchor in the swirling currents of his own memory.
She looked breathtaking. Not in a gown of white silk, but in a simple, elegant cheongsam of deep blue, its fabric shimmering subtly in the diffuse light. It was her choice. A quiet nod to the home they had left and the home they would build together. Her English had improved in leaps and bounds, but in moments of profound emotion, she reverted to the language of her heart, the tongue that held the cadence of her soul.
“你準備好未呀?” she whispered, her eyes, dark and expressive, searching his. -Are you ready?-
Pearl squeezed her hand, a whole universe of feeling passing between them in that simple gesture. “我準備好啦.” -I’m ready.-
The ceremony was a brief, secular affair in a wood-paneled office, presided over by a cheerful clerk with a kind, crinkly smile. There were no guests, no family, just the two of them and the weight of all they had endured to reach this quiet, sun-drenched room. When it came time for the vows, Pearl spoke in Cantonese, his voice thick with an emotion that surprised him.
“Leyue,” he began, his gaze locked on hers. “我應承你，我會用我嘅一生去愛你，保護你，珍惜你。無論未來點樣，我都會喺你身邊.” -I promise you, I will use my whole life to love you, to protect you, to cherish you. No matter what the future holds, I will be by your side.-
Tears welled in her eyes as she replied, her own voice a soft, unwavering melody. “Pearl, 我都一樣。我會永遠支持你，理解你。你係我嘅所有.” -Pearl, me too. I will always support you, understand you. You are my everything.-
And with a simple exchange of rings and a kiss that tasted of salt and tears and the promise of a future finally free from the ghosts of the past, they were married. Professor Pearl Wou, the time-traveling mathematician who had walked through the fire of history, and Leyue Wou, the woman who had waited for him, who had seen the darkness in his eyes and had not been afraid.
They emerged from City Hall into the thin California sunshine, the fog beginning to burn off. The world felt new, scrubbed clean. They had money to spend, a luxury that still felt alien to Pearl. His book, The Calculus of Conflict, had been published six months earlier to the kind of reception that most academics only dream of. It had become a global phenomenon, a runaway bestseller translated into forty languages.
The central thesis, the idea that had eluded him for so long, had come to him not in a flash of inspiration, but in a slow, dawning realization born of his own trauma. He had been trying to create a deterministic model, an equation that would predict war with the certainty of a physical law. But war, he had come to understand, was not a deterministic system. It was a probabilistic one.
He had proposed the "Wou Aggression Index," a complex, multi-layered probabilistic model that analyzed a nation's propensity for conflict. It was a staggering work of applied mathematics, combining econometric analysis, linguistic algorithms that scoured political rhetoric for key indicators of belligerence, and statistical models of military deployment. But the true breakthrough, the variable that no one had ever managed to quantify, was what he called the "Social Cohesion Delta." It was a measure of a nation's internal fragmentation—its levels of economic inequality, its racial and ethnic tensions, the trust, or lack thereof, in its institutions. He argued that a nation turning its aggression outward was often, in fact, a nation at war with itself. The probability of an invasion, he demonstrated with terrifying clarity, was a direct function of this internal decay.
The book didn't offer a crystal ball. It offered a diagnostic tool. It could tell a diplomat not just that a country was likely to become aggressive, but why. It pointed to the specific levers of de-escalation: targeted economic aid to reduce inequality, cultural exchange programs to foster understanding, international pressure to protect minority rights. It transformed foreign policy from a game of geopolitical chess into a science of preventative medicine.
The world hailed him as a genius, a visionary. The Nobel committee in Oslo had taken notice. But no one knew the terrible truth of how he had gathered his data. They saw the elegant equations, the rigorous statistical analysis. They didn't see the blood-soaked sands of Omaha Beach, the bombed-out streets of London, the smokestacks of Auschwitz. They didn't see the faces of the dead, the ghosts that haunted his dreams. That was his secret, his burden, a price he had paid for the knowledge that was now changing the world.
They picked up the car, a vintage, cherry-red Ford Mustang convertible, a ridiculous, exuberant indulgence that made Leyue laugh with a pure, unadulterated joy that was the most beautiful sound in the world. They put the top down and headed south on Highway 1, the Pacific Ocean a vast, shimmering expanse of blue to their right. The wind whipped through Leyue’s hair, and she threw her head back, her laughter carried away on the sea breeze.
“This is better than the MTR, eh?” Pearl shouted over the roar of the engine.
She just grinned, her eyes sparkling.
The coastline was a breathtaking panorama of rugged cliffs and crashing waves, of cypress trees bent into surreal shapes by the constant wind. It was a world of raw, untamed beauty, a stark contrast to the dense, vertical landscape of Hong Kong. Pearl looked at the ocean, its rhythmic, predictable surge and retreat a soothing balm to his frayed nerves. It was the same ocean that bordered his home, but it felt different here. The English Channel had been a gateway to a charnel house. This was a gateway to a new life.
They spent their first night in a small, ridiculously expensive hotel in Carmel-by-the-Sea, a place of fairytale cottages and art galleries. Their room had a balcony that overlooked the ocean, and they sat there as the sun dipped below the horizon, painting the sky in fiery strokes of orange and purple.
“好靚呀,” Leyue breathed, her head resting on his shoulder. -So beautiful.-
“是啊,” he agreed. -Yes.-
They were quiet for a long time, the only sound the rhythmic crash of the waves. Pearl found himself staring at the surf, at the white foam churning against the sand. He wasn't seeing California. He was seeing Normandy, the water turning red, the bodies of young men rolling in the tide.
Leyue sensed the shift in him, the sudden, almost imperceptible tensing of his muscles. She didn't ask him what was wrong. She had learned that direct questions only made him retreat further into himself. Instead, she just tightened her arm around him.
“我喺度陪你,” she said softly. -I'm here with you.-
The simple words, spoken in the language of their shared past, were a lifeline. He turned to her, his eyes full of a darkness that he knew she could see, but that she had never, not once, shied away from.
“Sometimes,” he began, his voice raspy, “I still see it. The water. The…the boys. They were so young, Leyue. Younger than my students.”
She listened, her expression a mixture of infinite sadness and unwavering love.
“It’s a strange thing,” he continued, the words tumbling out of him, a confession whispered into the twilight. “My book…it’s all about numbers, about statistics. The probability of survival, the casualty rates. I made a science out of it. But when you’re there…you’re not a statistic. You’re just a boy, scared and sick and praying that the next bullet doesn’t have your name on it. And the ones who don't make it…they’re not just numbers in a column. They’re…they were real.”
He was crying now, silent tears tracking paths through the day’s dust on his cheeks. Leyue held him, her small frame a bastion of strength. She rocked him gently, as if he were a child who had woken from a nightmare.
“我知道，我知道,” she murmured, stroking his hair. -I know, I know.-
She didn't know, not really. How could she? But she knew him. She knew the weight he carried, the ghosts he wrestled with. And in that moment, her quiet, unwavering presence was the only thing that kept him from being swept away by the tide of his own memories.
The next few days were a blur of sun and sea and the simple, uncomplicated joy of being together. They drove through the dramatic, wild beauty of Big Sur, stopping to watch the sea otters playing in the kelp beds. They walked barefoot on the beach at Santa Barbara, the sand warm beneath their feet. Leyue’s English grew more confident with each passing day. She would read the road signs aloud, her accent a charming, musical thing that made Pearl’s heart ache with love.
“Pfeiffer…Big…Sur…State…Park,” she would enunciate carefully, a look of intense concentration on her face. Then she would turn to him, her eyes sparkling with pride. “Did I say it right?”
“Perfect,” he would say, and she would beam.
He found himself talking more, not about the war, but about his work, about the beauty of mathematics, the elegant, underlying order of the universe. He explained the physics of the Golden Gate Bridge, the complex interplay of tension and compression that allowed it to soar so gracefully above the water. He described the strange, counterintuitive world of quantum mechanics, the probabilistic universe that was his intellectual home. She didn't always understand the details, but she listened with a rapt attention, fascinated not so much by the science as by the passion it ignited in him.
“你好叻仔啊，吳教授,” she would tease him, her eyes dancing. -You’re so clever, Professor Wu.-
In a hotel in Santa Monica, a place of Art Deco elegance and faded glamour, something shifted between them. They had just made love, a slow, tender rediscovery of each other, and were lying tangled in the soft white sheets, the late afternoon sun streaming through the window. Leyue’s fingers were tracing the scar on his thigh, the puckered, angry-looking flesh where the shrapnel had torn through him.
He flinched, an involuntary, reflexive movement.
She stopped. “Does it hurt?”
“No,” he said, his voice quiet. “Just…a memory.”
She looked at him, her gaze so direct, so full of a fierce, protective love that it almost took his breath away. She leaned down and kissed the scar, a soft, gentle pressure that was more intimate than any caress.
“你嘅所有，我都愛,” she whispered against his skin. -Everything that is you, I love.-
He knew then that he was going to be alright. The ghosts would still be there, he knew that. They would always be a part of him. But they no longer had the power to consume him. Leyue’s love was a shield, a sanctuary, a light that was strong enough to hold the darkness at bay.
Their last stop was San Diego. They found a small hotel in La Jolla, perched on a cliff overlooking the Pacific. They spent their last day on the beach, watching the surfers ride the waves and the pelicans dive for fish. As the sun began to set, casting a golden, ethereal glow over the water, Leyue turned to him.
“The Nobel Prize,” she said, the words a statement, not a question. “They announced the nominations this morning. It was on the news.”
Pearl just nodded, staring out at the horizon.
“How do you feel?” she asked.
He was quiet for a long moment, the sound of the waves filling the silence. “Like a fraud,” he said finally, the words raw and honest. “I feel like a fraud, Leyue. They’re calling me a peacemaker, a visionary. But I’m just…a witness. I saw things, terrible things, and I wrote them down in the language of mathematics. The men who died on that beach, the families who were gassed in those camps…they paid for that knowledge with their lives. And I’m going to get a medal for it.”
Leyue took his hand, her fingers warm and strong.
“你唔係呃人,” she said, her voice firm. -You are not a fraud.- She switched to English, wanting to be sure he understood the precise weight of her words. “You did not choose to see those things. But you chose what to do with what you saw. You chose to make…meaning. To help. To stop it from happening again.”
She looked at him, her eyes full of a fierce, unwavering belief in him that was more powerful than any prize, any accolade.
“你改變咗個世界，傻瓜,” she said, a small, sad smile playing on her lips. -You changed the world, silly.-
He looked at her, at this incredible woman who had seen the worst of him and had loved him anyway, who had walked with him through the valley of the shadow of death and had never let go of his hand. He had gone back in time to study the mathematics of war, but he had learned the most important lesson of all right here, in the present, in the quiet, unshakeable strength of their love.
He pulled her close, burying his face in her hair. The sun had set, and the first stars were beginning to appear in the darkening sky. The road trip was over. A new life was beginning. The equation, he finally understood, was not about predicting conflict. It was about creating peace. And peace, he knew now, was not the absence of war. It was the presence of love.