The Simulacrum Particle

A scientist loses the one person who made life make sense-his partner, his lover, the only one who truly understood the machine they were building together. A time-leap device-unfinished, unstable, born from ambition and hope.
She dies before it's done.
He finishes it after. Alone.
Not out of scientific curiosity, but because grief is a kind of gravity-it pulls you toward impossible things.
He uses it. Not to go back, but forward. Sideways. Into a version of reality where she might still be breathing.
And she is.
But things are... wrong.
Familiar, yet unfamiliar.
She's alive, yes-but something in the world isn't.
And as he tries to make sense of it all, he begins to understand why no one tampers with time.
Why maybe... no one ever should.