If I use E x t = h bar(adsbygoogle = window.adsbygoogle || []).push({});

and put t = age of universe in seconds = 10^ 18 seconds,

E x 10^18 = 10 ^ -34 gives E = 10^ -52 Joules.

So if an oscillator of some sort in the early universe absorbed a photon,

and emitted the energy of that photon today, there would be an uncertainty in the photon energy of 10 ^ -52 Joules.This energy corresponds to a wavelength of 10 ^ 26 metres - the current size of the universe.

This makes sense because a particle can't exist outside of the universe -

the maximum uncertainty in its position has to equal the size of the universe.

So can the uncertainty principle be used to measure the size of the universe?

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# Size of universe and uncertainty principle

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