cosmology - Does the Universe have finite number of particles?

I read that the number of atoms in the entire observable universe is estimated to be within the range of $10^{78}$ to $10^{82}$.

Does the Universe have finite number of particles? If so, how could it be determined?

Answer

The universe must contain a finite energy - sum of all matter and fields - or the mass-equivalent would collapse within its own gravitation. Said mass-energy is fractionally partitioned among elementary particles and their agglomerates. One then strongly expects there are a finite number of particles including extremely low energy photons and neutrinos.