Cosmology: The Story of the Universe
Like Duolingo, but for Cosmology: The Story of the Universe. 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.
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Key ideas in Cosmology: The Story of the Universe
- Parallax is the only direct geometric distance measurement
- Luminosity is the total energy a star emits per second
- Earth's position shifts by 2 AU over six months
- Standard candles have a known 'wattage' regardless of location
- Closer stars show a larger angular shift than distant ones
- Apparent brightness decreases with the square of the distance
- How Earth's orbit creates the baseline for parallax measurements
- The relationship between apparent brightness and intrinsic luminosity
- Longer pulsation periods indicate higher absolute magnitude
- Leavitt's Law links timing directly to light output
- Cepheids are bright enough to be seen in nearby galaxies
- They all explode at the same mass limit (Chandrasekhar limit)
- Their extreme brightness makes them visible across billions of light-years
- Parallax anchors the entire system to physical units
- Using Cepheid pulsation to determine distance
- Each rung is calibrated using the distance from the previous one
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 Cosmology: The Story of the Universe 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.
When astronomers talk about a star's luminosity, what are they actually measuring?
Get it right to open this lesson and 74 more in the app.
Where Cosmology: The Story of the Universe takes you
Journey from the first fraction of a second to the heat death of the universe. Master the physics of expansion, the mystery of dark energy, and the mathematical models that define our reality.
- 1
Measuring the Infinite
- The Cosmic Distance Ladder
- Redshift and Hubble’s Law
- 2
The Geometry of Space-Time
- The Friedmann Equations
- Curvature and Critical Density
- 3
The Dark Universe
- The Case for Dark Matter
- Dark Energy and Lambda
- 4
The Early Universe
- Big Bang Nucleosynthesis
- Baryogenesis and Asymmetry
- The Photon Epoch and Recombination
- 5
The Cosmic Microwave Background
- Anisotropies and the Power Spectrum
- Polarization and B-Modes
- 6
Cosmic Dawn and Structure
- Jeans Instability and Collapse
- The Cosmic Web
- Reionization
- 7
The Inflationary Paradigm
- The Horizon and Flatness Problems
- The Inflaton Field
- 8
The Ultimate Destiny
- The Big Freeze and Heat Death
- The Big Rip and Big Crunch
- The Multiverse and Eternal Inflation
8 sections · 19 units · 75 levels. Built to play, not to enroll.
You pick the voice
Cosmology: The Story of the Universe is taught in the The Professor style: clear, structured, thorough. 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 Cosmology: The Story of the Universe today.
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