Here's why:
* Different sounds: The "short a" sound can be produced in slightly different ways depending on the language and dialect. For example, the "a" in "cat" might sound slightly different from the "a" in "hat" in some accents.
* Multiple symbols: Even within a single language, different spellings can represent the same sound. For example, the "a" in "cat" and the "o" in "cot" both make the short "a" sound.
* International Phonetic Alphabet: The International Phonetic Alphabet (IPA) uses the symbol [æ] to represent the short "a" sound in words like "cat," "hat," and "bag." This is a universal symbol used by linguists and phoneticians.
Therefore, the closest thing to a symbol for the short "a" sound is the IPA symbol [æ].