The inner product is equal to zero when the wavefunctions of two particles are orthogonal. This happens when the two particles are in different energy states or have different momentum.

## Other related questions:

### Q: What is inner product in quantum mechanics?

A: In quantum mechanics, the inner product is a way of taking the “dot product” of two quantum states. It is used to calculate the probability of finding a particle in a particular state.

### Q: How do you find the inner product of quantum mechanics?

A: There is no one definitive answer to this question, as the inner product in quantum mechanics can be defined in various ways depending on the particular context and interpretation. However, a few common examples of inner products in quantum mechanics include the Hilbert space inner product, the bra-ket inner product, and the Dirac inner product.

### Q: What is the inner product of two quantum states?

A: The inner product of two quantum states is the expectation value of the operator that represents the observable quantity associated with those states.

### Q: Is every inner product space complete?

A: No, not every inner product space is complete.