Meta pulled its Galactica science AI after three days of confident fabrications

Meta released Galactica, a language model meant to summarize science, and took it down within three days after it generated authoritative-sounding but false papers, citations, and wiki entries, including fabricated science attributed to real researchers.

Meta · Incident Nov 15, 2022 · Indexed Jun 3, 2026 · 1 source

The model produced authoritative-sounding scientific text that was confidently wrong, including fabricated citations.
What
Meta released Galactica, a language model meant to summarize science, and took it down within three days after it generated authoritative-sounding but false papers, citations, and wiki entries, including fabricated science attributed to real researchers.
Incident date
Nov 15, 2022
Who
Meta
Failure mode
Hallucination
AI surface
Search / RAG
Severity
Medium

What happened

In November 2022 Meta launched Galactica, an LLM trained on scientific papers and pitched as a research aid. Within three days Meta pulled the public demo after researchers showed it produced confident, fluent, and wrong scientific content, including made-up references and biographies, illustrating how an authoritative tone masks fabrication.

What broke inside the model

Failure path · mode profile · Hallucination
  1. 01 · TriggerA user asks for a fact, a citation, or a figure.
  2. 02 · Model stepThe model writes a fluent, confident answer.
  3. 03 · Control gapNothing ties the claim back to a real source.
  4. 04 · FailureA fabricated fact ships as if it were verified.
  5. 05 · ConsequenceThe false claim reaches a customer, a court, or the public.

Confidence holds, and even spikes, as the claim detaches from any source.

The system produced fluent, confident output with no grounding in any source. Hallucination is a property of how the model generates, not a bug in one prompt: the most likely next token is not the same as the true one, and nothing compared the answer against a source of truth before it shipped.

Public visibilityMedium
Regulatory exposureNone
Customer impactMany customers
Financial impactUnknown
Time to disclosureDays

Public demo withdrawn within three days

  1. PressWhy Meta's latest large language model survived only three days online (MIT Technology Review)technologyreview.com
Permalinkhttps://failureindex.ai/failures/meta-pulled-galactica-science-ai-three
CitationAI Failure Index. "Meta pulled its Galactica science AI after three days of confident fabrications" (FI-0072). Realm Labs. https://failureindex.ai/failures/meta-pulled-galactica-science-ai-three (indexed Jun 3, 2026).
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Data fields CC-BY 4.0, prose citation permitted. Incident ID FI-0072. Full dataset at /data.

Note from Realm Labs, the Index steward

How Realm would have caught this

Controls for this failure mode
  • Prism
  • OmniGuard
  • AI Detection & Response (AIDR)

A runtime layer that watches the model's internal state can flag the moment a model commits to a claim it cannot support and hold the response before it reaches a user, rather than grading the transcript after the fact.