fasklyvning

I’m not finding a widely recognized concept named “fasklyvning” in available sources. It may be a misspelling or a term from a specific field or language. Could you please clarify one of the following?

- Which language is intended (Swedish, Norwegian, Danish, or another)?

- The field or context (for example chemistry/physics, geology, biology, meteorology)?

- A possible alternate spelling or related term (for example “fas-” plus another word, or a term like “faseklyvning” or “fase splitting” in a particular literature)?

If you can specify the intended meaning or context, I can draft a concise, neutral wiki-style article (under 300 words) with an appropriate structure and tone.