The field particle of gravitational forces is known as . . . . .

Answer

To solve the question "The field particle of gravitational forces is known as . . . . .", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Gravitational Forces**:
- Gravitational forces are the attractive forces that exist between any two masses. They are described by Newton's law of universal gravitation.

2. **Identifying Field Particles**:
- In physics, a field particle is a theoretical particle that mediates a fundamental force. For example, in electromagnetism, the field particle is the photon.

3. **Field Particle for Gravity**:
- In the context of gravitational forces, the field particle that mediates the gravitational interaction is known as the graviton.

4. **Conclusion**:
- Therefore, the answer to the question is that the field particle of gravitational forces is known as the **graviton**.

### Final Answer:
The field particle of gravitational forces is known as **graviton**.

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