Heat had a sound if you listened closely enough.

It whispered through the radiators in the chemistry wing, sighed beneath the hum of fluorescent lights, lived in the tiny spaces between breath and silence.  Emma heard it everywhere that Monday morning—the murmur of a world still cooling from the weekend’s rain.

She arrived early, sleeves rolled, coffee in hand.  The lab was empty except for the slow drip of condensation from the window frame.  She placed her notebook on the table and watched the droplets gather, slide, and fall.  They left brief trails like unfinished equations.

When Liam entered, the door clicked once, precise as always.  He carried a tray of new samples: glass vials filled with amber liquid that caught the light and scattered it across his sleeve.

“Morning,” she said.

“Morning,” he replied.  “You’re early.”

“I could say the same.”

“I’m always early.”

“Then maybe I’m catching up.”

He set the tray down.  The faint scent of caramelized sugar rose into the air.  It smelled like a promise and a warning at once.

Ms. Green followed moments later, her voice brisk but cheerful.  “Good, both of you here.  Today we start thermal analysis—how temperature changes flavor perception.  Simple in theory, unpredictable in practice.  Record everything.”

“Unpredictable,” Emma echoed.  “My favorite word.”

Liam adjusted his goggles.  “Mine is accuracy.”

“That explains everything about us.”

He almost smiled.

They began with the basics.  The first sample—sugar solution heated to forty degrees—tasted bright, almost floral.  The second, cooler, carried a dull bitterness she couldn’t name.  Liam noted each reaction with clinical precision, his handwriting even and exact.  She described sensations instead: warmth that reminded her of laughter, cold that sounded like distance.

He wrote down both.

When they reached the higher temperatures, the air itself thickened.  Steam curled above the burners, catching the light in gold threads.  Emma felt sweat gather at the back of her neck, but she didn’t step away.  Heat made everything sharper—the colors, the air, the space between them.

“Record the difference,” he said.

“I am.  It’s louder.”

“Louder?”

“The way heat moves.  It has a voice if you stop thinking like a scientist.”

“I don’t know any other way to think.”

“Then maybe you should learn.”

He didn’t answer, but his pen slowed.

Ms. Green moved among the tables, checking their progress.  “Remember,” she reminded, “temperature reveals reaction.  Pay attention to what changes first.”

For Emma, it was heartbeat.  For Liam, it was breath.

They worked in near silence, interrupted only by the hiss of burners and the clink of glass.  Outside, sunlight pressed through the fogged windows, turning every surface into a mirror.  She caught his reflection once—focused, distant, beautiful in a way that made her forget the formula she was supposed to be writing.

When Ms. Green dismissed them for a short break, Emma lingered.  Her hand brushed the metal counter; it was hot enough to sting.  She didn’t pull away.

“Careful,” Liam said.  “You’ll burn yourself.”

“Maybe I want to see how much heat I can take.”

“That’s not an experiment worth repeating.”

“Depends on the result.”

He looked at her, expression unreadable, then turned off the burner.

The silence that followed was heavier than steam.

After Ms. Green left to fetch additional supplies, the room felt suddenly too large.  The air trembled with leftover warmth.  Emma poured water into a beaker, watching the ripples fade.

“Do you ever think,” she asked quietly, “that heat isn’t about temperature at all?”

“What else would it be?”

“Contact.  Pressure.  Something alive.”

He folded his arms.  “You’re anthropomorphizing physics.”

“Or maybe physics has been human all along.”

He didn’t argue.

She held the beaker up to the light.  The reflection painted her face in fractured gold.  “What do you see?”

“A liquid sample.”

“I see a memory waiting to happen.”

His reply was so soft she almost missed it.  “Then write it down before it evaporates.”

When the bell rang to signal the next class, neither moved.  The clock ticked, counting time like a metronome they refused to follow.

Finally he said, “You should cool the samples.”

“Right,” she murmured.  “Wouldn’t want the data to melt.”

He packed his notes; she capped the burners.  The scent of sugar lingered, sweet and scorched.

As they left the lab, Ms. Green returned, arms full of folders.  “Tomorrow,” she called after them, “we begin phase two—heat under pressure.  Bring steady hands and open minds.”

Emma glanced at Liam.  “Pressure,” she said.  “Think we can handle that?”

“We’ll find out,” he answered.

Outside, the corridor shimmered with light, every surface reflecting a little of the day’s heat back at them.  She could still feel it on her skin, quiet and alive.

It wasn’t just temperature anymore.