we say, that in waves only energy is propagated and not mass. Then how do waves like light travel in vacuum ?

Question

i mean, if there's not matter in space to act as a energy transferrer, then how does it travel? (light cant have mass as its totally energy)
or even if u say that photons carry that energy in that form, then is it wrong to say that in waves only energy and no matter is transferred?
THANKS A LOT FOR UR HELP......

Answer 1

Light is a form of electromagnetic radiation.
Electromagnetic radiation is composed of a set of orthogonally positioned electric and magnetic fields. Maxwell's laws of electromagnetism state that a changing electric field will generate a magnetic field, and, a changing magnetic field will induce an electric field. These two oscillating fields form a self propagating electromagnetic wave which, unlike ordinary waves requiring a medium to propagate, is able to travel through a vacuum.

Electric and magnetic fields can easily exist in a vacuum, and it is these fields which make up light. The changing electric field creates a changing magnetic field (and vice-versa). When this happens, the wave can propagate on its own without any medium to transfer through.

Answer 2

A wave can be energy traveling through a mass. For example, in the ocean the water does not advance when a wave passes by, only the energy passes by through the water. Light is electromagnetic in nature and this type of energy does not require a medium to travel. It is a wave in that it has a cyclic peak and trough, but these are electric and magnetic and can travel through mass but does not require mass to propagate. Energy can be changed into mass using E-mc^2. Energy can be changed from momentum to impulse when it strikes a mass.

Answer 3

Matter can travel in waves ( example water in oceans ). Actually all matter has a wave function according to Shroedinger's equation, alas the frequency might be very small.

Anther example of matter traveling in waves are several types of radiation other than gamma rays where protons or neutrons are emitted from atoms nuclei

Vacuum in outer space is not " empty' space ( call it fields) are created by matter , possibly with the exchange of some ( still hypothetical) particle called graviton.

Now lets take a beam of light at the edge of the universe. Then the moment it arrives it is a field like space. keep in mind that energy is a form of condensed energy, and is convertible to mass following Einstein famous equation E=m*c*c

Answer 4

I'm not sure what's bothering you. If you say only energy is transferred and not mass how does that imply that you need mass to transfer the energy? It doesn't seem to follow to me.

When you say 'photons carry energy in that form' what form do you mean? Is this the idea that photons transfer momentum at c and so have a mass equivalent? No it can't be as you claim that light can't have mass as it is total energy (despite e=mc^2)... but then there is that 'or'...

But that statement about waves not transferring mass seems to apply to acoustic waves on a necessarily macroscopic scale or possibly deep water waves and certainly doesn't apply at the sort of microscopic scale where photons and electrons exhibit obvious wave-like properties I mean electrons have mass, so do beta particles, even neutrons.

I'm puzzled - what's your question?

Answer 5

That's a good question. Light can act like a wave and it can also act as a particle. Look up the split gate experiment. This is one of the things that might be explained by string theory. Hope you can explain it to me someday.