> precisely 21 cm Imprecise use of "precise" in the strapline. According to https://en.wikipedia.org/wiki/Hydrogen_line the best measurement of it so far is 21.106114054160 +/- 0.000000000030 cm
Ok, we've made the title not be precise now.
One quantum transition makes light at 21 cm
61–70 of 188 posts
Re: One quantum transition makes light at 21 cm
#62> precisely 21 cm Imprecise use of "precise" in the strapline. According to https://en.wikipedia.org/wiki/Hydrogen_line the best measurement of it so far is 21.106114054160 +/- 0.000000000030 cm
That not just imprecise usage of that term; it’s completely incorrect. The correct term would be its exact opposite, “approximately”.
Indiscreet discrete mathematician checking in. If they said "exactly" we'd have a real problem. Instead, "precisely" in this context means "human eye cannot distinguish from exact value at a stone's throw."
Yes, physicists and engineers hate me, why do you ask?
Re: One quantum transition makes light at 21 cm
#63Re: One quantum transition makes light at 21 cm
#64Amazing article! It seems incredibly to weird to hear about transitions causing photons at 21cm wavelength; I guess I'm only used to seeing (no pun intended) much shorter wavelengths at hundreds of nanometers.
It does feel a little odd that something the size of 5.29×10⁻¹¹ meter can create something 10 billion times larger.
I mean, I understand how and why, but it feels odd.
Re: One quantum transition makes light at 21 cm
#65> precisely 21 cm Imprecise use of "precise" in the strapline. According to https://en.wikipedia.org/wiki/Hydrogen_line the best measurement of it so far is 21.106114054160 +/- 0.000000000030 cm
That not just imprecise usage of that term; it’s completely incorrect. The correct term would be its exact opposite, “approximately”.
so the claim is inaccurate by 1mm and missing precision data. I'd call it inaccurate and imprecise XD
Re: One quantum transition makes light at 21 cm
#66Re: One quantum transition makes light at 21 cm
#67In Contact the alien beacon arrives at 4.4623 GHz. Pi times the Hydrogen line...
But do they know what is a second?
Re: One quantum transition makes light at 21 cm
#68[stub for offtopicness] [come on you guys]
Ah, so the answer to life, the universe, and everything was actually 42/2 …
Re: One quantum transition makes light at 21 cm
#69> precisely 21 cm Imprecise use of "precise" in the strapline. According to https://en.wikipedia.org/wiki/Hydrogen_line the best measurement of it so far is 21.106114054160 +/- 0.000000000030 cm
On the other hand, since it's a property of the universe maybe now's the time to define 21 cm as this value.
then cm will become a bit longer and it'll break many things