Starting the next day, with the acquisition of a talented rival-turned-accomplice in Kazune, I pursued time travel research with renewed vigor. The two of us brainstormed not just in the research room, but at the park, at the cafe, at karaoke, at each other’s houses, sometimes even at Otakitchen. This passion led to achievements in our regular research too, and the two of us rapidly rose through the ranks. As a result, we gained access to tools that were previously off-limits, and our research progressed even further.
Meanwhile, I visited the intersection every day to talk to Shiori. Sometimes Kazune would tag along and “talk” to her through me. I lived a fulfilling life both in and out of the lab. But in the end, with no leads for time travel and poor Shiori eternally trapped at the crosswalk, another full decade passed.
✦ ✦ ✦
“Here’s your beer.”
Once the bartender set my glass down on the counter, I picked it up and drank it one slow sip at a time. Before I knew it, I was pushing forty, too old to chug drinks anymore. Gazing at the little anime figurine in front of me, I found myself admiring its craftsmanship.
This bar was located on the second floor of Otakitchen, the restaurant the director had recommended to me ten years back, and as with the first floor, every inch was covered in anime posters and figurines. After Kazune and I became regulars at Otakitchen, we started coming up here too. Same bartender and chef for the past ten years straight.
“Rough day, Hidaka-san?”
“My research is going nowhere these days, and I’m starting to burn out.”
Over the past ten years, imaginary science had progressed by leaps and bounds. The director’s IP capsules had been implemented around the world, enabling the exchange of information between parallel worlds through optional shifts. As a result, the multiverse essentially turned into a giant quantum computer, which led to the ability to observe imaginary elements directly, and that in turn led to even more breakthroughs.
The first discovery Kazune and I made together was the answer to why I was the only one who could see and hear Shiori.
Observing imaginary elements directly enabled us to measure Shiori’s IP without a physical body. Then, when we compared her IP with mine, we found that one segment was a perfect match. This suggested that our IPs must have synced up somehow when we climbed into the IP capsule and parallel shifted together. That was how I, and only I, could see and hear her. The thought of us carrying a part of each other warmed my heart.
Incidentally, the process of researching eventually made it impossible to keep the nature of my relationship with Shiori a secret any longer, so with her blessing, I told Kazune the full truth. She reacted pretty calmly, as if she suspected as much already.
IP bands had become a household item as well. The law required doctors to take IP measurements for newborn babies and get them fitted for an IP band with World Zero pre-registered. The whole world now accepted alternate universes as fact.
My father’s research into IP stabilization was complete as well. By monitoring the target’s imaginary elements at all times, they could be “locked” to prevent parallel shifts. This was mostly used to prevent unexpected shifts during important events like weddings, and also to prevent criminals from fleeing to other worlds.
And so, imaginary science had become an inescapable part of everyday life. Recognizing its value, the Japanese government established several new laws as well as a Ministry of Imaginary Technology. As a result, our laboratory was reclassified as a National Research and Development Agency and renamed the Japan National Imaginary Science Research Institute. My mother and father were still director and vice-director, respectively, but they were retiring soon. It wouldn’t stop them from carrying on with their research, but they both seemed ready to pass on the torch. At the rate things were going, Kazune and I were the most likely candidates.
Amid the glorious forward charge of imaginary science, however, I still hadn’t found a method of time travel. It felt like I had overlooked something—something critical, yet most likely extremely simple. But common sense always got in the way of imagination, so if I had to guess, Kazune and I had yet to truly think outside the box.
So, what was the answer? I just didn’t know. Frustrated, I downed my beer.
“Slow your roll, pal. You’re no young pup anymore,” the bartender smirked wryly as he took my empty glass.
I was getting tired of my usual beer, so I flipped open the menu and debated ordering something different for a change. As I scanned down the list, however, I spotted an uncommon option.
“You guys carry Guinness here?” A dark, near-black Irish dry stout. Supposedly people in Ireland drank it basically every day.
“Ah, yes, we started stocking it at a customer’s request. Ever had it?”
“A few times when I was younger. Maybe I should have it again for old times’ sake.”
“Sure thing.” He set an empty glass on the counter.
“Where is it?”
“I’m about to pour it. Check this out.”
Grinning, the bartender pulled the cork out of a bottle of Guinness and poured it in at full speed. The dark beer immediately turned to foam as it filled the glass. But then, something strange happened.
As the beer level began to rise from the bottom of the glass, I expected the bubbles to be pushed up along with it, and yet…they were sinking, rapidly. I stared blankly at the bizarre phenomenon. Something crazy was happening right in front of my eyes—I could feel it in my gut.
“What am I looking at?”
“Isn’t it cool? It’s called a Guinness Cascade. I don’t know how it works though.”
Thinking logically, it was pretty simple. Due to the viscosity of the beer, when the bubbles rose, the liquid within close proximity was pushed up along with them. But because its density was greater than that of the bubbles, that liquid was then pushed out to the edges, and a vortex was created within the widest part of the glass as the beer subsequently pushed the bubbles back down. And so, the bubbles “cascaded” with the beer along the edges—then rose back up at the center of the glass, where you couldn’t see it.
They don’t just look like they’re sinking… Some of them really are sinking!
“Viscosity of the beer… Bubbles… Imaginary elements… Yes, something like imaginary viscosity… Buoyancy of bubbles… Imaginary density… Sea and Bubbles of Imaginary Elements… Viscosity and buoyancy… Measure IP… Overwrite… Lock…”
The bartender called my name. “Hidaka-san? What’s wrong?”
At last, I had found it. This was what Kazune and I had overlooked by thinking inside the box.
Bubbles can sink!