I imagine a physicist would invoke entropy to describe the diffusion of pressure waves and vibration into other forms of energy. Neuroscience might explain the propagation of signals from the cochlea into the brain. A psychologist could hypothesise on the influence of music on our mood and ideas. A philosopher might talk about the influence of music on the way we build our society and how that feeds back into our music. In this way, the music never stops, it continues on as echos rippling through through the universe.

The Langoliers eat it

It keeps traveling. If you splash some water, where does the wave go? Same question - it terms into something you can no longer see or hear... It never goes away. It becomes part of the world, forever

Music is what you hear - but it was only ever sound waves

All these physics answers! The funnest explanation for a kid is just that music is only there when you're listening to it. If you don't listen, there's no music. When you start listening again, music comes back. Then ask if they can hear the music of the wind.

we hang it on a wall of silence in the room of our imagination

It's still there, it's just in the past now.

If my words did glow with the gold of sunshine And my tunes were played on the harp unstrung Would you hear my voice come through the music? Would you hold it near as it were your own? It's a hand-me-down, the thoughts are broken Perhaps they're better left unsung I don't know, don't really care Let there be songs to fill the air Ripple in still water When there is no pebble tossed Nor wind to blow

"And can you please tell me, oh

Where do broken hearts go?
Can they find their way home
Back to the open arms
Of a love that's waiting there?
And if somebody loves you
Won't they always love you?"

Really reminded me of this - the incorrect, useless, but poetic answer could be that it's just like with love. Into the open arms of the music thats waiting there.

It goes into the ears.

If we can try with every day
To make it better as it goes
With any luck then I suppose
The music never ends

Category error.

Tell the truth in simple. I was annoyed to learn that there aren't any crawlies that go back up your throath if you swallow toothpaste.

"Ultimately it increases entropy... let me tell you about the heat death of the universe..."

"No, Mom! I'm still afraid of the False Vacuum monster laying underneath my ground state!"

Heat. Everything ends up as heat.

You absorb it into your soul and it changes you irreversibly forever.

As the waves from ocean, the music crashes on the beaches in your ears