Light Delay · Episode 3
The Math
A father teaches his nine-year-old son a rule for working out how long his voice takes to reach home, and the son asks the one question the rule can't answer. In 2088, Theo does one more sum: how old his father would be tonight.
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A summer night in the kitchen, crickets outside.
Theo Message nine. Monday, the eleventh of March, twenty forty-one. Seven-forty in the morning. Thirty-four hours into the burn.
A soft playback chime.
The ship under thrust, a deep steady engine rumble.
Michael Good morning. Math class.
Michael You're going to want a pencil. Go on, I'll wait. Well, I won't wait. I can't wait, that's the whole problem. But pretend I'm waiting.
Michael Okay. Here's the rule. Nobody else gets this rule, it's just for you. You take the hours since the big engine started. You multiply that number by itself. And then you divide by five. And that's the delay. In seconds.
Michael It's a little bit more than that, really, but five is easier, and it's close enough for Halcyon work.
Michael So. Right now it's been thirty-four hours. Thirty-four times thirty-four is eleven hundred and sixty-five. Divide by five. Two hundred and thirty-three seconds. About four minutes.
Michael Check my work. You will anyway. Over.
The message ends with a soft click.
The series theme, with the title card over it.
Announcer Light Delay, presented by the VoiceFrequency Network. Episode three: The Math.
Early morning in the kitchen, birds outside, a coffee maker finishing.
Theo Dana Whitcomb left a message at eight. She said she'd like to tell me, over lunch, at my convenience, what Perihelion could offer. She's at the Hilton downtown. I didn't call back.
Theo Mikey had the box open on the kitchen table before I'd finished my coffee.
A cardboard box set down on a table, and its lid lifted off.
Mikey Dad. There's a cereal box in here.
Theo Don't bend it.
Mikey This is the cereal box? You kept the actual cereal box?
Theo My mother kept it. She gave it back to me when I turned thirty. She'd had it in a drawer for twenty-one years.
Mikey There's writing all over it. "Ship gets there. Dad is fifty. I hear it. I am fifty-six. Six years." And then "six years" again, underlined. Three times.
Theo I was very sure about the six years.
Mikey And there's a drawing. Is that the ship?
Theo That's my dad.
Mikey Your handwriting hasn't changed.
Theo Don't.
Mikey Did he really teach you all this? Or did you just like math?
Theo He taught me the first rule. It's in tonight's messages. Everything after that, I worked out on my own, because he wasn't there to ask. I suppose that's why I teach it.
A summer night in the kitchen, crickets outside.
Mikey Thirty-four times thirty-four is not eleven hundred and sixty-five.
Theo No. It's eleven fifty-six.
Mikey He got it wrong.
Theo He always got it wrong. I told you. I caught it before school. I sent it back with a big red circle drawn around it on my mother's tablet. It got to him four minutes later. That was the first time in my life I'd ever corrected my father.
A soft playback chime.
Theo Message ten. Tuesday, six p.m. Sixty-eight hours.
The ship under thrust, a deep steady engine rumble.
Michael Okay. Okay. I've been informed. By the official delay calculator of the Tamsin. Thirty-four times thirty-four is eleven fifty-six, not eleven sixty-five. I switched two numbers. A man flies a ship to another star, and he switches two numbers.
Michael Anika saw your red circle. She says you're hired. She says from now on, nobody on this ship says a delay out loud until you've checked it.
Michael So. It's sixty-eight hours. Sixty-eight times sixty-eight, divided by five. I'm not going to say the answer. You say the answer. Write it on the fridge.
Michael Here's what I can tell you. My knees have stopped being mad at me. Lena found a deck of cards. Tomas cheats. And the coffee up here tastes exactly like the coffee at home, which tells you something about the coffee at home. Over.
The message ends with a soft click.
Back in the kitchen.
Mikey Sixty-eight times sixty-eight.
Theo Four thousand six hundred and twenty-four. Divide by five, nine hundred and twenty-four seconds. Fifteen and a half minutes. It went on the fridge. It stayed on the fridge for six years.
A soft playback chime.
Theo Message eleven. Wednesday, seven p.m. Ninety-three hours.
The ship under thrust, a deep steady engine rumble.
Michael Homework. Real homework this time. When does the delay get to one hour?
Michael You know the rule. Hours times hours, divided by five, is seconds. And an hour is three thousand six hundred seconds. So you go backwards. You'll need to do a square root. Your mother can show you the button. And when you've got it, I want you to find the day and the time, and write it on the calendar in the kitchen. Then we'll both know when it's coming.
Michael Don't tell me the answer. I want to see if you get there before I do. Over.
The message ends with a soft click.
Back in the kitchen.
Theo Friday, the fifteenth of March. Eleven-fifty in the morning. I wrote it on the calendar in red, and I drew a clock face next to it.
Theo It was wrong, of course. Dividing by five instead of the real number made me about four hours late. It happened at eight that morning, while I was at school. I didn't find that out until I was sixteen.
Mikey Did you tell him?
Theo That night I didn't send him the answer. I sent him a question instead.
Mikey What question?
Theo I'd been looking at the rule. Hours times hours. And I worked out that it doesn't just get bigger. It gets bigger faster. Every day, it grows more than it did the day before.
Theo So I asked him when it gets smaller.
A soft playback chime.
Theo Message twelve. Thursday. Two o'clock in the morning.
The ship under thrust, a deep steady engine rumble.
Michael Hey, buddy. It's late here. I've been lying in my bunk since your message came in, trying to work out how to answer it. You asked me when it gets smaller.
Michael I'm going to tell you the truth, because you'd find it out anyway. You always do. It doesn't. Not while I'm going away.
Michael For about a year, the engine keeps pushing, and the delay keeps growing faster, like your rule says. Then we stop pushing, and we coast, and it grows slower. But it still grows. Every single day it's a little more. It never gets smaller while I'm going away from you.
Michael It only gets smaller when I turn around.
Michael But here's the thing they don't put in the math. The delay is how long it takes my voice to get to you. It's not how long it takes me to think about you. That part's instant. That part is faster than light. It's the only thing that is.
Michael Go back to sleep. I know you're awake. Over.
The message ends with a soft click.
Back in the kitchen.
Mikey "When I turn around."
Theo I heard that too.
Mikey Not "if".
Theo Not "if". I never noticed it, the first time. I was nine. I heard "when", and I thought it meant when.
Mikey Same time tomorrow?
Theo Same time.
Footsteps going up a wooden staircase.
A summer night in the kitchen, crickets outside.
A pencil writing on paper.
Theo I promised Mikey one more sum. I did it after he'd gone up, on the back of an envelope from Perihelion.
Theo My father reached Halcyon at fifty. On his clock, the trip took twelve years. Once he stopped moving, his clock and mine went back to running at the same speed. And the message that told me he'd arrived took twenty-two years to get here.
Theo So, fifty, plus twenty-two.
Theo If he's alive, my father is seventy-two tonight.
Theo Mikey came back down for a glass of water and saw the envelope.
Mikey Seventy-two.
Theo Seventy-two.
Mikey If you sent him something tonight. How long?
Theo Twenty-two years. He'd hear it in twenty-one-ten. He'd be ninety-four.
Mikey People live to ninety-four.
Theo I didn't say anything to that.
Theo Message thirteen, tomorrow.
The closing theme, the piano under the announcer.
Announcer You've been listening to episode three of Light Delay, on the VoiceFrequency Network.
Announcer In our next episode: the delay passes an hour. And in the archive, Theo finds messages that were never meant for him.