There are problems. You can only travel between the two ends of your fabricated wormhole. You will never travel back to observe World War II. Dinosaurs will never come roaring through your portal to wreak havoc on the modern world, scaly metaphors for fascism and the fall of an empire.
Also, you do not have a stable wormhole and no plausible means of creating it.
For a while your theories make you a star in the field. A few awards fall into your lap, and you believe the words engraved in the bases.
Then the accolades slip away and are redirected into the careers of colleagues with more plausible equations. Your lab space is reassigned to the nanoengineering unit, which filed actionable patents while you imagined flying about with a wormhole.
Eventually you wonder if only your dog still cares about you.
You abandon the time machine, encrypt your files, and drift between ideas. Jane watches and follows as you walk around the house in a bathrobe. She still limps a little, a physical recording of past trauma. She rolls on her back on the couch as you waste a few hours of your life on an old sitcom. She growls as you rub her belly. The deep menace in this sound sometimes frightens people who don’t know that this is how she speaks her love.
She watches over you.
Then she struggles to get up, limping more noticeably, sensing that you’re upset and wondering how she can protect you.
She brushes her gray muzzle against your face, watching you to know how she should feel. You pretend to be fine and call her a good girl. She is a good girl. Your misery comes from watching her body falter, from the inevitable progress toward a terrible decision, but she can’t know that.
You’re sitting on the kitchen floor next to her as she pushes her food bowl around the tiles. The fridge rises like a steel monolith at your back. It is a place for giants. You feel secure next to her on the cool floor. She bumps you with the food bowl and uses your weight to pin it down while she finishes her dinner. You pat her side, and she burps before lying down, slowly, against your hip. You’ve forgotten to make yourself dinner.
Then it’s the day when she dies, although she doesn’t know it.
No one watches over you now. You’re free to spend nights in the lab, catching fitful naps under a desk, wondering what previous resident stuck their chewed gum in a line of Morse code under the rim. The gum is the record of passing time, the message that is the past.
Then you understand: no one moves through time. Time is merely a form of encryption, much like the files on your computer. The past is decoded; the future remains locked into a cypher. The present is merely a floating translation point between encoded and decoded information.
There is only one timeline, one message. You might want to change it—to save a planeload of doomed passengers or avert a war. But you’re free of the burden of that power. When you go back, you’re simply reencrypting the timestring. Your equations show, with almost total confidence, that you won’t be able to change anything.
You’re going back for one reason—to see your dog again.
When you go back in time, it hurts more than you thought possible. The universe presses its weight against you. Exploding molecules are welded back together. Healed wounds are torn open before ceasing to exist. Disentangled particles fall back under each other’s painful influence.
Pages come in contact, stick, and knit back together. Your memories are stripped from you and scrambled into code.
When you go back, you don’t know you’ve gone back. You roll back the clock and experience your life again for the first time. You’re yourself, just as you always were, and always will be forever. You’re like Jane. You have no memory of the future. You just exist.
You walk past rows of metal cages—dogs clamoring for attention or turning in tight circles or huddling with their backs to the door. None of them are the dog you’re looking for. You hear the deep resonance of her voice from two rows down. The shelter staff tells you that this dog is scheduled to be euthanized. No one has come to pick her up. She has tried to bite two handlers and has been labeled a threat. In honor of her unknown origins, they have named her Jane Dog. Her barks rise in amplitude, as if she’s trying to catch up with someone who is walking away.
When you pass her cage, she leaps up against the wire mesh, breathes in your face, and watches you. Her flank is shaved over a ragged wound and her front leg is splinted. The staff member warns you to be careful. Jane’s eyes are nearly level with yours, and in them is an unwavering sense of purpose.
You tell the staff all the right things. You understand that she is dangerous, that she will require time and training and patience and structure and socialization and still may always be in some way broken. You leave the building tethered to each other.
In three years you will watch the needle slide into the soft fur and cry uncontrollably, and struggle to remember life without her. You’ll bury your face in the thick sable neck and feel more adrift than anyone has ever been in time.
It hurts the same amount every time, although you never remember the reencryptions from one to the next. You collapse eventualities like a tent being folded in on itself. You bend along your dimensions in bone-shearing recombinations.
Every time you return to the past is the first time. You have no memory of how many times you’ve gone back to be with her.
She loves the woods. Every breath is a painting: ochre splatter patterns of squirrels flashed through with bright blue glimpses of every dog who has peed on the scabby trunk of rotten oak. Green swirls of skunk sift through the trees.
You are tethered together in the woods when a man runs around the bend in a trail, arms pumping, puffing with exertion. You startle. Jane feels the tremor through the leash, and you don’t have time to pull her in close to your leg before the man runs past. She lunges, wrenching your shoulder with unexpected fury. The man pitches away and falls into the dead leaves. You’re apologizing and stepping forward to help him up, but Jane is barking and pulling, and the man looks more terrified every time you step closer.
“Holy shit!” he yells. “Control your dog!”
The man’s fear has transformed into anger. He’s tugging at the leg of his shorts, and you see the fabric is ripped. You’re apologizing and asking if he’s all right. There is no blood, no wound. You part forever.
In two years the needle slides in and she’s dead. She’s dead and you’re back again to where she’s gone, your past decoded and painfully plain.
Did she always lunge for the man?
The memory feels fresh as a wound. Before you went back, did you remember the torn cloth in the man’s hand, the angular wedge of exposed skin? Did Jane wrench your shoulder?
Perhaps it always happened this way. There is no denying the fact that you remember it. The other possibility is terrifying: that the timeline is softer and more subject to revision than you had theorized.
If you can alter the timestring, then maybe you can make things better. This is almost as terrifying a prospect as helplessness.
There’s no way of knowing for sure. The lunge is coded into the universe now, a fossil pressed into stone. Somewhere out there, a man remembers the day he nearly was attacked.
What you are doing here suddenly feels strange and dangerous as theft. You walk the house alone. When you do laundry, trying to pretend that everything is normal, the lint trap is clean of dog hair, and you cry into the warm clothes.
So you go back again.
When you return, when the needle goes into the soft fur, she whines for a moment, her eyes going wide.