Historical clue formulations

• Torque symbol, in physics — 2026-09-18
• Letter after sigma — 2026-08-31
• Mathematical constant equal to two times pi — 2026-06-21
• 19th of 24 — 2026-05-03
• ___ particle — 2026-03-28
• Letter symbolizing the ratio of a circle's circumference to its radius — 2026-02-01
• Symbol for the ratio of a circle's circumference to its radius — 2025-10-30
• Time constant symbol in physics — 2025-08-29
• ___ particle — 2025-07-06
• Cross shape — 2025-04-19
• Greek letter that's the symbol for torque — 2025-02-16
• Greek T — 2024-12-24
• Sigma follower — 2024-10-06
• Sigma follower — 2024-06-18
• Letter before upsilon — 2024-04-24
• Greek T — 2024-04-08
• T that comes before a Y — 2024-03-27
• Greek "T" — 2024-03-18
• Letter after sigma — 2024-03-03
• Letter after sigma — 2023-12-26
• Letter between sigma and upsilon — 2023-08-21
• Sigma follower — 2023-08-01
• Cross shape — 2023-07-21
• Greek letter that's a symbol for torque — 2023-05-14
• Fraternity letter — 2023-04-20
• Delta ___ Chi, house in "Animal House" — 2022-10-09
• Elementary particle named for a Greek letter — 2022-09-18
• ___ particle — 2022-06-12
• T as in Tartarus — 2022-04-24
• Letter after sigma — 2022-04-18
• Letter after sigma — 2022-03-14
• Time constant symbol — 2022-03-05
• Symbol for torque in mechanics — 2022-02-25
• Sigma/upsilon go-between — 2022-01-18
• Sigma's follower — 2021-10-18
• Letter before upsilon — 2021-08-24
• Upsilon preceder — 2021-08-01
• ___ lepton (elementary particle) — 2021-07-18
• Letter after sigma — 2021-05-24
• T, in a sorority — 2021-02-23
• Torque symbol — 2020-12-18
• Fraternity letter — 2020-09-08
• Greek consonant — 2020-07-30
• It comes three after pi — 2020-03-14
• Cross shape — 2020-03-01
• Two before 34-Down — 2020-02-29
• Sigma follower — 2019-11-06
• Kind of cross — 2019-10-25
• ___ particle — 2019-09-05
• Letter after sigma — 2019-08-05