The stromatolite colony had grown in ways that violated every principle of evolutionary biology Ethan knew.
Not just larger—more complex. The layering showed variations that should have taken millions of years to develop through random mutation and selection. Branching structures. Specialized zones. The bacterial community had leaped forward as if someone had compressed epochs into seconds.
Someone had.
Ethan pulled back from the Engine, heart rate climbing. The time differential showed three hundred years had passed on Aethon during his moment of distraction. Standard rate. But the colony's development suggested active intervention, not mere observation.
He hadn't meant to do anything.
That was the problem.
---
By noon, he'd replicated the effect twice more, both times accidentally.
First: reaching for his phone while watching a tidal pool. The Engine pulsed. When he refocused, the pool contained primitive multicellular algae that hadn't existed seconds before.
Second: sneezing. Just a sneeze, his attention fragmenting for half a second. The darkness flared and a volcanic vent system he'd been monitoring shifted three degrees north, creating a new thermal gradient.
Neither intervention cost him anything he could measure. No tremors, no fatigue. But the pattern was clear: divided attention created instability. The Engine responded to intention, yes, but it also responded to *inattention*. To the quantum foam of half-formed thoughts that flickered through consciousness every moment.
He was dangerous.
---
Maya called at 2 PM. He almost didn't answer.
"You sound terrible," she said.
"I'm fine."
"Ethan." Her voice carried the particular firmness she used when peer-reviewing sloppy papers. "You missed lunch. You missed two lunches. When's the last time you ate?"
He looked at the granola bar wrappers scattered across Abel's desk. Three? Four? "I've been working."
"On what?"
The question hung between them. He could hear traffic through her phone—she was outside, probably walking between buildings at the university. Normal life. Normal physics. Peer review and tenure committees and the comfortable certainty that the universe ran on laws no human will could alter.
"Inheritance stuff," he said. "Abel left... complicated records."
"Right." She didn't believe him. "Look, I'm coming over. You need to eat something that didn't come from a vending machine."
"Maya—"
"Six o'clock. I'm bringing Ethiopian. Don't make me eat alone."
She hung up before he could argue.
---
Ethan spent the afternoon developing safeguards.
First: physical distance. He moved the Engine to Abel's safe, a fireproof box in the basement. Spun the combination lock. Walked upstairs. The separation felt like stretching a rubber band, but it held. He could still sense Aethon, still access the observation interface through that quantum entanglement Abel's notes hinted at, but the feedback was muted. Safer.
Second: meditation. He'd never been good at it—his mind was a particle accelerator, constantly colliding thoughts—but if divided attention was the problem, then focused attention was the solution. He set a timer for twenty minutes and sat in Abel's reading chair, breathing, trying to quiet the chaos.
He lasted four minutes before his leg started tremoring.
Third: documentation. He opened his encrypted notes and added a new section:
*INTERVENTION LOG*
*Entry 1: Stromatolite acceleration. Unintentional. Cost: Unknown.*
*Entry 2: Algae manifestation. Unintentional. Cost: Unknown.*
*Entry 3: Volcanic shift. Unintentional. Cost: Unknown.*
*Hypothesis: The Engine responds to mental state, not just conscious intent. Subconscious thoughts may trigger effects. Need better control before observation becomes creation becomes catastrophe.*
He stopped typing. The word *catastrophe* sat on the screen like an accusation.
On Aethon, his three accidents had already propagated through the ecosystem. The accelerated stromatolites would out-compete their neighbors. The algae would consume resources other organisms needed. The shifted thermal vent would alter current patterns, change nutrient distribution, reshape the entire continental shelf over geological time.
Three moments of inattention. Three permanent changes.
And he still didn't know what it was costing him.
---
Maya arrived at six with enough food for four people and questions in her eyes.
They ate in Abel's kitchen while she talked about her research—something about cosmic microwave background anomalies that might suggest bubble universe collisions—and he pretended to follow. The food was good. He hadn't realized how hungry he was.
"You're doing it again," Maya said.
"What?"
"That thing. Where you're here but not here." She set down her fork. "What's going on, Ethan? And don't say inheritance paperwork. I've known you too long."
He could tell her. Should tell her, maybe. Maya understood quantum mechanics, understood that the universe was stranger than common sense suggested. She might even believe him.
But if he told her, she'd want to see. And if she saw, she'd want to study it. And if she studied it, she'd want to publish. That was what scientists did—they shared knowledge, built on each other's work, pursued truth collectively.
Except some truths weren't meant to be collective.
"I found something of Abel's," he said carefully. "A research project. I'm trying to understand it."
Maya studied him across the table. "Is it dangerous?"
"Yes."
"Do you need help?"
He thought of the stromatolites, evolving in fast-forward because he'd caught a coffee mug. Thought of the Engine in the basement safe, humming with potential catastrophe.
"Not yet," he said.
It was the kindest lie he'd ever told.
---
After Maya left, Ethan returned to the basement.
He opened the safe. The Engine pulsed once in greeting, and the darkness at its center showed him Aethon: a world where his carelessness had already rewritten three billion years of future history.
He touched the surface deliberately this time. Felt the warmth. Spoke a single word into the void:
"Teach me."
The darkness answered with a vision: Abel, decades younger, standing in this same basement with this same Engine, making these same mistakes. Learning this same lesson.
The cost wasn't vitality.
The cost was consequence.