Fourteen elements have no single atomic weight
Carbon is printed as 12.011 on every wall chart. IUPAC does not publish a single figure for carbon, or for thirteen othe...
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The standard behind your headphone warning advises against the warning
Your iPhone's 80 dB for 40 hours limit comes from ITU-T H.870, implementing WHO recommendations. That standard says dose...
A TDS meter cannot measure total dissolved solids
Total dissolved solids is defined as a weight — filter, evaporate, weigh the residue at 180 °C. A handheld pen measures...
One sky, three verdicts: why Singapore says unhealthy and Malaysia says moderate
The same 70 micrograms of fine particulate reads 116 on Singapore's PSI, 96 on Malaysia's API and 161 on the US AQI. Alm...
Your CO2 monitor's red line is a 19th-century number, and it is drifting
The 1000 ppm line is Pettenkofer's, proposed in the 19th century as a proxy for whether a room smelled stuffy. ASHRAE re...
Leap seconds end on 20 May 2027, and the Earth has already turned around
The committee that has inserted 27 leap seconds since 1972 is proposing to stop, and to let clock time drift up to an ho...
Mitochondrial DNA does not use the genetic code you were taught
Four codons differ between the standard genetic code and the one your mitochondria use, and two of them are stop signals...
Why your DNA ancestry estimate is vaguer if you are Asian
A result full of "Broadly" labels is telling you something real, but not about your ancestry. One company's own document...
When a DNA match could be your grandparent or your half-sibling
A match sharing around 1,700 centimorgans could be a grandparent, an aunt or uncle, or a half-sibling. The averages for...
Mid-Autumn is two days before the full moon this year
The festival lands on 25 September and the moon reaches full on the 27th. The gap is larger than usual, it is one day ra...
Why a 1,000-Qubit Computer Has Zero Usable Qubits
Physical qubits and logical qubits are different currencies. At current error rates one logical qubit costs about 1,681...
How Much Faster Is Quantum Search, Actually?
We ran Grover's algorithm and counted the oracle calls. Over 4,096 items it looked 50 times against a classical average...
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