Eventually will there be no new music that can be composed?

Status Quo has made a living for 50 years playing the same notes in a slightly different order using the same 3 chords. What you state is not possible because there is an infinite number of variations of notes. However there will be more court cases as more and more tunes will sound similar!

surely there isn't an infinite number of notes or variations that we can hear I wouldn't have thought.

With the invention of new electronic and digital instruments, even the same notes sound different. So what I say is probably true.  However the way pop music is going, I'm glad  won't be around to find out if I'm right!

Haven't you heard Liechtenstein's national anthem?

No but I seen a few of his paintings!

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https://www.youtube.com/watch?v=kTClvNG3E78


What does this sound like?

i had this same thought last night - strange 


anyway ,by the time it happens they can go back to  the start and rehash all the old tunes

hang on ! that's already been done

Watched MTV for a few mins yesterday. Chris Brown Ayo video is like a carbon copy of Puff and Biggs Mo Money Mo Problems. This coming off the back of Drake dropping an entire verse Puff did on his last album So hip hop has  run out of lyrics and videos!!

Actually there is a finite amount of notes and melodies which has pretty much been reached (all the best ones used up ages ago) hence almost every song nowadays is a rehash or blatant lift from another.

so someone could actually compose a melody/song and be very similar to another melody/song without actually ever hearing the "old" version.

Then gets sued for copyright

surely there isn't an infinite number of notes or variations that we can hear I wouldn't have thought.

There's not really a practically finite number of notes though as you can pick any tone you like for a note. In the west we use fixed points, like E,F,F# and G, etc. Other cultures use scales that contain microtones - notes between 'our' notes. An Indian scale, for instance, I think is 22 notes long because of these microtones. So in theory there's a complexity possible that, in the West, hasn't really been explored yet.

Here's an example using quatertones, notes half way between semitone, roughly, on two pianos tuned for the purpose:
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https://www.youtube.com/watch?v=B9WPfkXQa_Y

Its a sequence of notes that sound sweet to the ears and yes we maybe coming to the end
https://www.youtube.com/watch?v=e9TmQQQGddQ