This report documents the findings of an unauthorized expedition to Underworld Level B61, conducted between December 12 and December 19, 2199. The expedition team consisted of six individuals — four with deep-level exploration experience, one field medic, and myself as lead researcher. Funding was provided by an anonymous benefactor through a series of cryptocurrency transfers that I did not attempt to trace. Our objective was to investigate reports of temporal anomalies at extreme depth.

At Level B61, we encountered what I can only describe as temporal discontinuity. Our chronometers — three independent atomic-synced devices — began to disagree. Over the course of four hours at depth, Clock A recorded 4 hours 0 minutes. Clock B recorded 3 hours 47 minutes. Clock C recorded 4 hours 22 minutes. The discrepancy is not explainable by equipment malfunction, as all three clocks were calibrated against the GLMZ municipal time standard before descent and agreed perfectly through Level B58.

More disturbing were the subjective time distortions reported by team members. Expedition member Suki Abramov-Chen reported experiencing approximately ten minutes during which she observed the rest of the team moving in extreme slow motion — "like watching video at one-tenth speed" — while she moved and thought normally. She used this time to walk approximately 200 meters down a corridor and back. The rest of the team confirms she disappeared and reappeared within what they experienced as roughly thirty seconds.

At the deepest point of our penetration, we found writing on the walls — not graffiti, but precise technical diagrams etched into the concrete with what appears to be a laser cutting tool. The diagrams depict what our team physicist identified as a modified Penrose diagram of a rotating Kerr metric — a mathematical description of spacetime around a rotating black hole. The diagrams include annotations in a notation system none of us recognized, but which appears internally consistent and mathematically sophisticated. The etch marks show weathering consistent with at least fifty years of exposure, yet the content references theoretical physics concepts that were only published in the 2190s.

I am aware of how this sounds. I have submitted my raw data, clock logs, biometric recordings, and photographs of the wall etchings to three independent verification services. Two have confirmed the data is unaltered. The third refused to comment. I am publishing this report because I believe the scientific community has an obligation to investigate, even when the findings are uncomfortable.