Identify the mathematical expression in the image.

The image shows the mathematical expression 3.4 times 10 to the power of -19, which can be written as (3.4 cdot 10^{-19}). This expression represents a number in scientific notation. The number 3.4 is multiplied by 10 raised to the power of -19. This means 3.4 is multiplied by a very small number (0.0000000000000000001). In decimal form, this would be 0.00000000000000000034. So, the final answer is: (3.4 cdot 10^{-19})