There is a behavior of the standard string.Split where it accepts an empty array of delimiter and assumes that we want to use white-space characters.
From the Remarks section of String.Split:
If the separator parameter is null or contains no characters, white-space characters are assumed to be the delimiters. White-space characters are defined by the Unicode standard and the Char.IsWhiteSpace method returns true if they are passed to it.
It is convenient to also have this behavior in the multi-lingual context where we don't have to maintain a complete list of white-space characters on our own.