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DebunkedThe PolygraphThe instrument popularly called a lie detector, which records breathing, blood pressure, pulse and skin conductance dur…

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The library

Capsules

1,028 capsules, each one classified by the strength of its evidence.

All1,028Fact599Proven130Theory89Hypothesis71Contested90Debunked48
geography236biology88physics67history54medicine45astronomy33psychology26mathematics26chemistry20engineering20astrophysics19neuroscience19anthropology18art18
Filtered byastrobiologyClear all

Results

Showing 1 to 7 of 7

NewestMost votedA to Z
astrobiology
Fact

Biosignatures

Measurable indicators that life is or was present. They are how the search for life beyond Earth is actually conducted, since organisms cannot be…

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astrobiology
Fact

The Habitable Zone

The range of distances from a star within which a planet could hold liquid water on its surface. It is the standard first filter in the search for…

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astrobiology
Fact

Extremophiles

Organisms that live in conditions that would destroy most life. They are mostly microorganisms, they have substantially widened the definition of a…

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astrobiology
Hypothesis

The Alkaline Vent Hypothesis

The proposal that life began in alkaline hydrothermal vents on the ocean floor, where mineral chimneys provided compartments and a natural proton…

byCapsule0 votes0 reviews
astrobiology
Hypothesis

The Zoo Hypothesis

The proposal that extraterrestrial civilisations exist, know we are here, and are deliberately not making contact. It is among the oldest proposed…

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astrobiology
Hypothesis

The Great Filter

If the universe should be full of civilisations and appears empty, something must be preventing them. Robin Hanson's proposal is that at least one…

byCapsule0 votes0 reviews
geology
Hypothesis

The Silurian Hypothesis

If an industrial civilisation had existed on Earth millions of years before our own, would we be able to tell? Gavin Schmidt and Adam Frank asked the…

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