We cannot directly see subatomic particles like electrons and protons because of their extremely small size and the limitations of our human senses and the tools we use for observation. Here are a few reasons why they are not visible to the naked eye:
Size: Subatomic particles, such as electrons and protons, are much smaller than the wavelengths of visible light. Our eyes can only detect light within a certain range of wavelengths, typically between 400 to 700 nanometers. Electrons and protons are on the scale of femtometers (10^-15 meters), which is many orders of magnitude smaller than the wavelengths of visible light. They are simply too tiny to interact with visible light in a way that would allow us to see them.
Interaction with light: Subatomic particles do not interact with light in the same way that macroscopic objects do. Light interacts with matter through various processes like absorption, reflection, and scattering. However, at the subatomic level, the interactions are governed by quantum mechanics, which introduces wave-particle duality. Electrons, for example, exhibit wave-like behavior and can only be detected indirectly through their interactions with other particles or by the effects they produce.
Experimental limitations: Even with advanced scientific instruments like microscopes, the resolution is limited by the wavelength of the probing particles or waves. Electron microscopes, for instance, use a beam of accelerated electrons instead of light to achieve higher resolution. However, while they allow us to indirectly observe subatomic particles, these techniques still have limitations in terms of the accuracy and precision of the measurements.
Instead of directly "seeing" subatomic particles, scientists rely on indirect evidence and observations obtained through various experimental techniques. These include particle accelerators, cloud chambers, bubble chambers, and detectors that measure the effects of subatomic particles on their surroundings. By studying the behavior and properties of these particles indirectly, scientists have been able to develop models and theories that describe their nature and interactions.