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Why do photons have no mass while W and Z bosons have large masses?

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A diagram of a cylindrical vessel containing gas, with a movable piston held down by a weight. Countless small dots beneath the piston represent gas particles in rapid, random motion, illustrating Bernoulli's model of gas pressure. — physics As conceived by Daniel Bernoulli in *Hydrodynamica* (1738), gases consist of numerous particles in rapid random motion. He assumed that the pressure of a gas is produced by the direct impact of the particles on the walls of the container.

In the framework of electroweak theory, the difference in mass between photons and the W and Z bosons is explained by the Higgs mechanism.12

While gauge theories naturally require carrier particles to be massless, the weak force is observed to have a very short range, which implies that its carriers must be massive. To resolve this, physicists utilize the concept of "hidden symmetry" or symmetry breaking.342

The Higgs field permeates all of space and interacts with elementary particles to endow them with mass. The W and Z bosons acquire their large masses through their interactions with this field. In contrast, the photon does not interact with the Higgs field in this way, allowing it to remain massless. This mechanism preserves the underlying mathematical symmetry of the electroweak theory while explaining why the electromagnetic and weak forces manifest so differently in our universe.124