>>>1. Fuel gets used up, as hydrogen gets converted to helium and metals.
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>>That just means stars and galaxies have a finite lifetime. Not the Universe.
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>Well, both stars, and the Universe, continue to exist... but not in the same form. There will come a time when no stars will shine as they do now.
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>>>2. Dying stars leave a residue that can't get recycled into new stars.
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>>Not even if they fall into another star?
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>That is an unlikely event that will happen very seldomly for any individual star. And, if a star does fall into another star, it still doesn't solve the problem. This might be easiest to see in the case of a black hole. A black hole merging with another star will simply form a bigger black hole.


Considering every star is in a galaxy that is essentially collapsing on itself, it seems pretty likely that every star will find its demise in the black hole in the center of its galaxy, where none of the laws of physics do us much good.


>>>3. There is lots of observational evidence that some billions of years ago, the Universe was different from now.
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>>Actually, new telescopes usually reveal the Universe is older than we thought, hence inflationary models.
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>Do some reading on steady-state theories. There was a time when such steady-state theories were quite popular. To be accurate, unlike the theory you are proposing, the steady-state theories proposed an expanding Universe. This was to account for observational evidence, and for calculations (based on the General Theory of Relativity, I believe) that a static Universe won't be stable.

Those calculations were done before the galaxies were discovered as their own groups of stars.

The evidence is that all the galaxies are indeed collapsing on themselves, and aren't infinitely stable.

But that again is a conclusion that should not be thrust upon the Universe as a whole.


> However, in those steady-state theories, new matter was gradually created "out of thin air", and the Universe maintained its general aspect. In other words, it could continue indefinitely into the past and future, without major changes in its aspect.
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>Today, the steady-state theories are no longer popular, because of the observational evidence that in the past, the Universe was indeed different from today. Quasars and active radio galaxies mainly appear at large distances, i.e., in the distant past.

Assuming quasars are correctly understood.