Writing a trillion trillion requires an understanding of place value and the use of scientific notation. In the short scale system, a trillion is one followed by 12 zeros, meaning it is written as 1,000,000,000,000. Therefore, to write a trillion trillion, we need to understand that it is equivalent to 1 followed by 24 zeros, or 1,000,000,000,000,000,000,000,000.

To simplify this large number, we can use scientific notation. Scientific notation is a way of expressing numbers as a product of a base number and a power of 10. In this case, we can express a trillion trillion as 1 x 10^24. This means that we start with the number 1 and move the decimal point 24 places to the right. This gives us the same number as 1,000,000,000,000,000,000,000,000.

To write a trillion trillion is to write the numerical representation of 1 x 10^24 or 1,000,000,000,000,000,000,000,000. This number is incredibly large and beyond the comprehension of many humans. However, it is still useful in scientific fields, including astronomy, physics, and chemistry, where numbers of this magnitude are often encountered.