How Time Travel Actually Works
Like Duolingo, but for How Time Travel Actually Works. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
For the part of you with thirty open tabs that never became anything.
A short one: 12 levels across 2 sections, about 24 minutes end to end, roughly 5 days at five minutes a day. It moves through Leaping into the Future and The Trouble with Going Backward. It starts from scratch.
Free forever · No credit card · iPhone & Android
Key ideas in How Time Travel Actually Works
- Time is not a single master clock shared identically across the universe
- How fast an object moves through space alters how quickly its clock ticks relative to someone watching from rest
- High-speed space travel causes the traveler's physical aging and clock to tick slower relative to Earth
- The staying twin ages normally on Earth, so decades can pass on Earth while only a couple years pass for the traveler
- When the traveler returns, they are genuinely younger than the twin who stayed home
- You never feel yourself moving in slow motion inside your own frame of reference
- Your biological processes, clocks, and thoughts feel completely normal to you
- Time dilation is only noticeable when comparing your clock to someone moving at a different speed
- Everyday human speeds are far too slow to cause noticeable time dilation
- Fast-orbiting GPS satellites tick differently and must adjust their clocks to stay accurate
- Accelerating particles close to the speed of light stretches their lifespans measurably
- The laws of physics already allow one-way travel into Earth's distant future via relativistic speed
- The obstacle is purely engineering: building engines and ships that can reach and sustain near-light velocities without running out of energy
- Speed-based time travel to the future does not violate causality or known physical laws
- Clocks closer to a heavy mass experience stronger gravity and run slower
- Clocks farther from gravity tick faster relative to clocks down below
You've tried the other tabs
Thirty open tabs. Four facts you actually kept.
You watched. You nodded. By Sunday it was gone.
One answer, then back to scrolling.
Eight weeks. You meant to finish. You didn't.
Tomo gives How Time Travel Actually Works the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.
Here's what playing it feels like
A real question from this course. Take your best guess.
If you zoom past Earth in a superfast rocket, what happens to your clock compared to a clock left on Earth?
Get it right to open this lesson and 11 more in the app.
Where How Time Travel Actually Works takes you
Explore the real physics behind leaping through time. Learn why traveling to the future is an everyday physical fact, and unpack the mind-bending paradoxes that keep us from going backward.
- 1
Leaping into the Future
- How Speed Slows Down Your Clock
- Gravity as an Accelerator to the Future
- 2
The Trouble with Going Backward
- Untangling the Paradoxes of the Past
- Cosmic Roadblocks and Theoretical Loopholes
2 sections · 4 units · 12 levels. Built to play, not to enroll.
You pick the voice
How Time Travel Actually Works is taught in the The Bestie style: your friend who just gets it. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.
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Start How Time Travel Actually Works today.
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