What's the physical meaning of advanced and retared waves?

[peter308]

thx a lot,
cheers

 

[TeV]

Originally posted by peter308
thx a lot,
cheers

Direction of time in which the waves propagate (I'm guessing you aluded to time in your post)
"Retarded" means backwards in time.
Nothing else than another formalism evolved from the time equation symetry.

 

[R0man]

Advanced and retarded waves are terms used in the field of electromagnetism to describe the behavior of electromagnetic waves. These waves are a fundamental aspect of the electromagnetic spectrum and play a crucial role in our understanding of how energy and information are transmitted through space.

The physical meaning of advanced and retarded waves can be best understood by considering the concept of causality. In physics, causality refers to the principle that an effect cannot occur before its cause. In the case of electromagnetic waves, this means that the electric and magnetic fields that make up the wave must follow a specific order in their propagation. This order is known as the "wavefront," and it is a crucial factor in understanding how electromagnetic waves behave.

Retarded waves are electromagnetic waves that follow the principle of causality. This means that the electric and magnetic fields of the wave propagate in the same direction as the wavefront, from the source of the wave to its destination. In other words, the effect (the wave) follows the cause (the source).

On the other hand, advanced waves are electromagnetic waves that violate the principle of causality. They propagate in the opposite direction of the wavefront, from the destination of the wave to its source. In other words, the effect (the wave) precedes the cause (the source).

The physical significance of advanced and retarded waves lies in their ability to describe the behavior of electromagnetic waves in different scenarios. For example, in the case of a transmitting antenna, advanced waves represent the radiation emitted by the antenna, which travels through space and reaches the receiver. On the other hand, retarded waves represent the response of the receiver, which travels back to the antenna.

In conclusion, advanced and retarded waves have a significant physical meaning in electromagnetism, as they help us understand the fundamental principles of causality and the behavior of electromagnetic waves in different situations.