Temperature

Decided: the tep, defined by fixing the Boltzmann constant k = 2;07 × 10^-1E (opus/tep), exact.

Why: 0 tep = freezing is what people actually need for weather and cooking (like Celsius). The size splits the gap between freezing and boiling into 100; equal steps (144 dec), so water freezes at 0 °t and boils at 100 °t - the dozenal version of Celsius's 0 and 100.

Advantage: freezing is 0 and boiling 100, so weather and cooking temperatures read like Celsius.

  • 1 tep = 0.694346 K (within 0.014% of 0;01 of the freezing-boiling gap)
  • 0 tep = freezing: exactly 289;485 ta (≈ 273.149 947 K, 53 µK (dec) below 0 °C; see below) - human focused; kelvin-style zero rejected
  • Triple point of water (273.16 K = 0.01 °C) ≈ 0;021 °t, not 0. The triple point has been a measured value (not exact) since SI's 2019 redefinition, so anchoring there would gain nothing
  • boiling (sea level) ≈ EE;E9 tep, effectively 100 (144 dec). (SI's Celsius isn't exact either: 99.974 °C)
  • 1 tep ≈ 0.694 °C ≈ 1.25 °F
  • body temperature ≈ 45;35 tep, room temperature (21 °C) ≈ 26 tep
  • absolute zero = -289;485 °t exactly (no nice ratio between absolute zero, freezing and boiling - fine)

Decided: absolute temperature (from absolute zero, for gas laws and physics) is written ta, spoken "tep absolute": 0 ta = absolute zero, and 0 °t = 289;485 ta, so ta = °t + 289;485 exactly (see the next decision). Everyday temperatures stay °t (or te), from freezing.

Why: most people will only ever use the everyday scale, so it keeps the plain names; the absolute scale just needs to be distinguishable, as K is from °C. "a" for absolute follows psia / psig (pounds per square inch absolute / gauge). Rejected: "tabs" and "tea" (English words).

Advantage: everyday temperatures keep the simple name, and physics still gets an absolute scale that can't be mistaken for it.

Decided: the zero of the everyday scale is a defined number: 0 °t = 289;485 ta exactly (≈ 273.149 947 K, 53 µK (dec) below 0 °C).

Why: this is how SI does it: 0 °C isn't defined as where water freezes, but as exactly 273.15 K, a number that is exact because it's written in SI's own unit, the kelvin. Written in ta, 273.15 K is 289;48517..., a fraction that never ends, so tying 0 °t to 0 °C would leave the offset between °t and ta inexact. Fixing it at 289;485 instead makes it exact and short. The 53 µK (dec) difference is far smaller than the accuracy of any real freezing point: dissolved air alone moves it by about 2 mK (dec).

Advantage: °t and ta convert exactly with one short number, and the zero can be rebuilt from k alone, with no water or air pressure needed.