The matter waves are

Options

A. Light waves
B. Sound waves
C. Stationary waves
D. Probabilistic waves

Answer

To answer the question "The matter waves are," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Matter Waves**: Matter waves are associated with particles, as proposed by Louis de Broglie. According to de Broglie's hypothesis, every moving particle has an associated wavelength.

2. **Definition of Matter Waves**: Matter waves are also known as de Broglie waves. They represent the wave-like behavior of particles, indicating that particles such as electrons exhibit both particle and wave properties.

3. **Wavelength of Matter Waves**: The wavelength (λ) of a matter wave can be calculated using the de Broglie equation:
\[ \lambda = \frac{h}{p} \]
where \( h \) is Planck's constant and \( p \) is the momentum of the particle.

4. **Probabilistic Nature**: Matter waves provide a probability distribution for finding a particle in a certain region of space. This means that the intensity of the matter wave at a point relates to the likelihood of locating the particle there.

5. **Conclusion**: Therefore, matter waves are also referred to as probabilistic waves because they describe the probability of finding a particle in a given location.

### Final Answer:
Matter waves are also known as de Broglie waves or probabilistic waves, as they provide a probability distribution for locating particles in space.

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