Determining the precise volume of all the known matter in the Universe if stripped of empty space between particles is a challenging task due to several factors, such as the uncertainty principle in quantum mechanics and the complex nature of particle interactions. However, I can provide you with a rough estimation based on current scientific knowledge.
The known matter in the Universe is primarily composed of atoms, which consist of a nucleus (protons and neutrons) surrounded by electrons. If we were to strip away the empty space between particles within an atom, we would be left with a densely packed nucleus.
Assuming we consider only the protons and neutrons in the nucleus (ignoring electrons for simplicity), we can estimate the volume of all known matter by considering the volume of a proton or neutron and multiplying it by the total number of protons and neutrons in the observable Universe.
The approximate radius of a proton or neutron is around 0.85 femtometers (1 femtometer = 10^(-15) meters). This gives a volume of about (4/3)π(0.85 fm)^3 ≈ 2.6 × 10^(-45) m^3 for each proton or neutron.
The observable Universe contains an estimated 10^80 protons and neutrons (though this number may vary depending on the assumptions and estimates used). Multiplying the volume of a single proton or neutron by the total number of protons and neutrons would yield a rough estimation of the volume of all known matter in the Universe without empty space.
Volume of all known matter = (2.6 × 10^(-45) m^3) × (10^80 particles) ≈ 2.6 × 10^(35) m^3.
Please note that this estimation is based on simplified assumptions and current scientific understanding. The actual volume could differ significantly due to the complexities of quantum mechanics, the uncertainty principle, and our incomplete knowledge of the nature of matter.