---
title: "The Long L"
description: "Lukáš Likavčan's title concept, taken from L in Frank Drake's 1961 equation for the number of detectable civilizations: how long a technological species stays around."
type: "glossary-term"
canonical_url: "https://antikythera.wiki/terms/the-long-l"
md_url: "https://antikythera.wiki/md/terms/the-long-l"
last_updated: "2026-09-06"
site: "Antikythera Wiki"
---

# The Long L

> A working definition written for this wiki from the reading notes; not Antikythera's own wording. From Antikythera Wiki (https://antikythera.wiki/terms/the-long-l), an independent guide to Antikythera's published work.

[Lukáš Likavčan](https://antikythera.wiki/people/lukas-likavcan)'s title concept, taken from L in Frank Drake's 1961 equation for the number of detectable civilizations: how long a technological species stays around. Likavčan treats L not as a value to estimate but as a bridge from SETI back to Earth, since a civilization endures only by keeping its planet habitable, and in section 7 as a qualitative threshold: the technosphere's metabolism becomes isomorphic with the biosphere's, so a long-lived species' technosignatures are indistinguishable from biosignatures and it "hides in plain sight". Its parts are Metabolic Alignment (the index), Substrate-Agnostic Ecology (the theory of layers), and Assisted Reproduction / Assisted Evolution (the practice); habitability, following Chakrabarty, replaces sustainability as the norm. It resonates with Bratton's Viable Planetarity and Paradox of Intelligence, but where Bratton asks whether intelligence is self-extinguishing, Likavčan reads the Fermi silence as evidence that expansionist civilizations burn out and survivors are indistinguishable from nature.

## Appears in

- [The Long L](https://antikythera.wiki/work/journal/longl) (2025-11-21)

_Glossary generated 2026-09-06._