Causal Domain Shear

Causal Domain Shear (CDS) is a theorized phenomenon in which separate causal domains experience slight differences in the flow of time relative to one another when the causal linkages between them are minimal.

First appearance and context

CDS is articulated by Fraa Orolo during preparations for Apert at the Concent of Saunt Edhar. While interviewing an artisan from extramuros in the New Library, with an amanuensis taking notes, Orolo describes his use of an old questionnaire as “a routine check for CDS,” i.e., a way to look for unexpected signs that time outside might have advanced differently than inside the math.

Definition and rationale

• A “causal domain” is any collection of things tightly linked by cause and effect. Because influence is limited by light cones and distance, boundaries between domains can be drawn approximately; members within a math are more strongly connected to each other than to distant strangers.
• If two entire domains were utterly severed—no causal linkages at all—the simplest assumption is that their times would run independently.
• If the domains are only loosely connected—imagine a single photon passing between them—their times need not be in perfect lockstep; a small relative slippage (“shear”) could exist.

Motivation and use

• The mathic way of life aims to reduce causal linkages with the world extramuros. CDS frames a question: could such weak coupling allow tiny differences in timekeeping between inside and outside?
• Practically, Orolo treats CDS as a lens for field checks: during rare openings of the gates, one should watch for subtle discrepancies that would be easy to overlook in day‑to‑day life.

Status

At present CDS is a hypothesis and a guiding thought experiment. No observation has been confirmed; it primarily serves to shape what careful observers look for, on the principle that “it is what you don’t expect that most needs looking for.”