Aiieee! It’s “traveling,” not “travelling.” Can’t physicists spell?
Physicists don’t do spells, It only looks like magic.
An aggressive litigation agency with a software house attached based in Redmond, WA decide “it’s ‘traveling’, not ‘travelling”,” but not all of us bow to Microsoft’s spell checker as the ultimate arbiter of English orthography. Many of us still defend the older convention, that used to apply almost universally on both sides of the Atlantic, that terminal letters are doubled when -ing or -ed is added in cases where the addition of an e would lengthen the vowel before the single consonant.
There are adequate testimonies to the use of travelling as the correct spelling for the present participle of the verb to travel, both online and in printed literature, that your complaint is completely invalid.
Both “traveling” and “travelling” are correct spellings. I believe Nature is a British periodical, and the later is actually the preferred spelling there.