Theus and Gemini Notebook (formerly NotebookLM)
Google renamed NotebookLM to Gemini Notebook in July 2026. It reads and cites one set of sources well. Theus keeps every study in one Research Base, with contradictions and gaps visible.
Reviewed October 2026. Statements about other products reflect the cited sources as of that date.
What Gemini Notebook does well
Cited answers from your sources
Chat answers use only the notebook’s sources, and each citation opens the quote in context.
Many source formats
PDFs, Word, PowerPoint and Google files, web pages, YouTube, audio, images and text.
Research that adds sources
Deep Research searches the web and can add its report and sources to a notebook.
Deep Research and new file types (November 2025) (opens in a new tab)
Gemini Notebook and Theus side by side
Different tools for different jobs. The aim isn’t to replace Gemini Notebook.
| Capability | Gemini NotebookReading and citing one source set | TheusGoverned research evidence |
|---|---|---|
| Source-grounded chat | Answers only from the notebook’s sources | Answers across the Research Base |
| Citations | Open the quote or image in context | Designed to attach Fact IDs that resolve to the original page |
| Unit of knowledge | Sources and quoted passages | Facts with method, sample, statistics and page |
| Finding new sources | Deep Research adds web sources to a notebook | Fill returns cited candidate facts for review |
| Contradictions and gaps | Says when the notebook’s sources can’t answer | Stay explicit and feed reviewed gap research |
| Consumer response testing | Chat can take a custom role | Moderated Panel grounded in your Research Base, labeled as hypotheses |
Where research needs more
A citation shows where a sentence came from. A governed fact also carries its method, sample, statistics and any studies that contradict it, across the whole organization’s evidence.
The study found significant differences between products.
Product A (7.2 ± 0.3) scored significantly higher than Product B (6.1 ± 0.4) on sweetness intensity (p < 0.05, Tukey HSD, n = 120 consumers, 9-point intensity scale).
The Theus fact keeps its Fact ID and source page. Illustrative example.
How Theus works on the same evidence
Research Base
Reports, tables and charts become facts that keep their statistics and page.
Expert
Dr. Theodore Sinclair answers across studies, shows contradictions and gaps, and says when the evidence can’t support a conclusion.
Panel
Dr. Evelyn Reed moderates a synthetic discussion grounded in your Research Base. Persona-only behavior is labeled, and results are hypotheses to test.
Need full synthetic category panels instead?
See ForethoughtDr. Evelyn Reed and Dr. Theodore Sinclair are fictional personas.
Why prompting a persona isn’t enough
Gemini Notebook’s chat can take a custom role. You get the model’s picture of a person, not that person.
Results vary by domain
Studies couldn’t reproduce known consumer effects such as the endowment effect and the sunk cost fallacy.
Sarstedt et al., Psychology & Marketing (2024) (opens in a new tab)
About a third replicated
GPT-3.5 reproduced 37.5% of the original results in the eight Many Labs 2 studies that could be analyzed.
Park et al., Behavior Research Methods (2024) (opens in a new tab)
Answers cluster around the average
Synthetic users varied less than people and missed meaningful subgroups.
Nielsen Norman Group, AI simulations studies (opens in a new tab)
That’s why Theus grounds panelists in your Research Base and treats every Panel result as a hypothesis to test with people.
Where each one fits
Reading a source set
Cited answers from one notebook.
Briefings
Audio and video summaries.
Workspace
Gemini in Gmail, Docs, Sheets and Meet.
Use Gemini Notebook to package sources, and Theus to hold the evidence.
Data handling
Review both against your own requirements.
Gemini Notebook Enterprise and Workspace
- Sources stored in your Google Cloud project, US or EU, deleted with the notebook.
- Customer-managed encryption keys, VPC Service Controls and audit logging.
- Google says Workspace data isn’t used to train Gemini models or for ads targeting.
Gemini Notebook Enterprise overview (opens in a new tab), Google Workspace AI features (opens in a new tab)
Theus
- Aigora is in final preparation for its independent SOC 2 Type II examination.
- Client data is not used to train foundation models.
- Theus (theus.aigora.ai) inference uses the Google Gemini API under its paid-service terms. Google receives prompts and responses for inference.