07/12/2025
The human senses are limited in what they can detect. For example, our eyes can only see light within a narrow range of frequencies, from about 430 to 770 terahertz. This range corresponds to the colors we perceive, from violet to red. Light outside this range, such as ultraviolet or infrared, exists all around us, but we cannot see it without special instruments.
Similarly, our ears can only hear sounds within a limited range, from 20 Hz to 20 kHz. Sounds below or above this range, like deep infrasound or very high-pitched ultrasonic frequencies, are present in the environment but go unnoticed by us. Many animals, like dogs, bats, and elephants, can detect these sounds, giving them a sense of the world that we cannot experience.
These limitations show that humans perceive only a tiny fraction of the world’s sensory information. There is a vast amount of activity both in light and sound that occurs around us without our awareness. Technology, such as cameras that detect infrared or microphones that record ultrasonic sounds, allows us to explore these hidden frequencies and better understand the universe and our environment.
Understanding these limits highlights the incredible potential of science and technology to expand human perception.