A photon, as a fundamental particle of light, does not require anything external to "make" it travel. Photons are inherently energetic entities that propagate through space. The motion of a photon arises from its wave-like nature and obeys the principles of wave propagation.
A photon can be described both as a particle and a wave. This duality is a fundamental aspect of quantum mechanics. As a wave, a photon exhibits properties such as interference, diffraction, and superposition, which are characteristic of wave behavior. These wave properties are described by the photon's wave function, which gives the probability amplitude distribution of the photon's position and momentum.
However, when a measurement is made to determine the properties of a photon, it behaves as a particle, with characteristics such as a well-defined position and momentum. This is known as the wave-particle duality.
It's important to note that a photon does not fluctuate or transition between being a particle and a wave in the conventional sense. Rather, its behavior depends on how it is observed or measured. In certain experiments, the wave-like properties of a photon become apparent, while in others, its particle-like properties dominate. The choice of experimental setup and measurement method determines the observed behavior.
In summary, a photon can be described as both a particle and a wave. Its motion is governed by its wave-like nature, and it exhibits wave-like properties such as interference and diffraction. However, when measured, it manifests particle-like characteristics. The wave-particle duality of a photon reflects the inherent probabilistic and complementary nature of quantum mechanics.