The belief that electrons repel each other is based on the principles of electrostatics and the observed behavior of charged particles. Electrons carry a negative charge, and according to the basic principles of electrostatics, like charges repel each other. This means that when two negatively charged electrons come close to each other, they experience a repulsive force that pushes them apart.
The repulsion between electrons can be explained by Coulomb's law, which states that the force between two charged particles is directly proportional to the product of their charges and inversely proportional to the square of the distance between them. Since electrons have the same negative charge, the force between them is repulsive.
However, it is important to note that the repulsion between electrons is counteracted by other forces, such as the attractive forces between electrons and the positively charged atomic nucleus. In atoms, electrons occupy specific energy levels or orbitals around the nucleus, and these energy levels are determined by the balance between the attractive and repulsive forces. The electrons are held in stable orbits due to the attractive force of the positively charged nucleus.
Additionally, the repulsion between electrons is mitigated by the quantum mechanical nature of electrons. According to quantum mechanics, electrons can exist in a state of superposition, meaning they can occupy multiple positions simultaneously. This allows electrons to spread out and occupy different regions around the nucleus, minimizing their repulsive interactions.
Overall, while electrons do repel each other due to their negative charges, other forces such as attractive forces from the nucleus and quantum mechanical effects play a crucial role in determining the structure and stability of atoms.