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Loop XXI

Loop XXI · Research & Education

Understand what lasts.

Bitcoin, self-custody, AI, and monetary systems. Ideas for practical use.

The Bitcoin Power Law

Bitcoin
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Model line
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Lower model line
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Bitcoin Model line Lower model line

Price history is loading. Model lines are illustrations, not price targets or floors. Power law model attributed to Giovanni Santostasi. Not investment advice.

Three ideas

Reading a model critically.

Model line

This illustration uses time raised to the 5.68 power. Its output is a model estimate, not fair value.

Lower model line

Drawn at 0.42 × the model line. This is a chosen multiplier, not a guaranteed price floor.

Monetary systems

Inflation changes purchasing power. Compare historical data, assumptions, and measurement periods before drawing conclusions. BLS CPI Inflation Calculator, Jan 1971 → Jul 2026.

Model line = 10−16.493 × days5.68
Lower line = 0.42 × model line

The time variable counts days from January 2009. A mathematical fit does not establish causation, future returns, or a reliable lower bound.

Power law model per Giovanni Santostasi — not investment advice.

Why it matters

Purchasing power over time.

1971–2026

Purchasing power, illustrated. Rounded estimates; not a live CPI feed.

For an official historical comparison, use the BLS CPI Inflation Calculator (Jan 1971 → Jul 2026) — not investment advice.

Learn by doing

See how a seed actually works.

A seed phrase is not a password. It is 12 or 24 words that encode random entropy, with a checksum on the final word. You can watch that happen without putting a single sat at risk.

Try the free, open-source Bitcoin Seed Tool. Roll dice into a seed, finish a partial phrase, derive BIP85 child seeds or test a forgotten passphrase, all in your browser. It is a learning tool only: never use it, or any online page, for a seed that protects real bitcoin. Independent of Loop XXI.

Put ideas into practice.

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