Question

How large of a volume would all of the known matter in the Universe occupy if stripped of all the the empty space between atoms making up molecules, subatomic particles making up atoms, and quarks making up subatomic particles?

Answer 1

To estimate the volume of all known matter in the universe, assuming it is stripped of all empty space, we'll make a few approximations and assumptions.

1. Estimating the number of atoms in the observable universe: The observable universe contains an estimated 10^80 atoms based on various scientific estimates.

2. Estimating the size of an atom: Atoms consist mostly of empty space, with a tiny nucleus at the center and electrons orbiting around it. The size of an atom is primarily determined by the extent of its electron cloud. As an approximation, we can consider the size of an atom to be on the order of 1 angstrom (10^-10 meters).

3. Accounting for the empty space within the nucleus: Even though atomic nuclei are very small compared to the overall size of an atom, they still contain protons and neutrons, which are composed of smaller particles called quarks. These quarks are also believed to have some spatial extent. However, the size of the nucleus is much smaller than the atomic size, so for simplicity, we'll neglect the empty space within the nucleus.

Now, let's calculate the estimated volume:

Number of atoms in the observable universe: 10^80 Size of an atom: 1 angstrom ≈ 10^-10 meters

Total volume of all atoms = (Number of atoms) * (Volume per atom) ≈ (10^80) * (4/3 * π * (10^-10)^3) ≈ 4.19 * 10^50 cubic meters

This calculation represents the approximate volume occupied by the atoms themselves, without considering the empty space within the atomic nuclei or between atoms.

It's important to note that this estimation assumes that all known matter in the universe is made up of atoms, which is not entirely accurate. There are other forms of matter, such as dark matter, which do not consist of atoms. Additionally, the observable universe might not account for the entirety of the universe, as there could be regions beyond our observable limits.

Nevertheless, this approximation provides a rough estimate of the volume that all known matter in the observable universe would occupy if compressed, neglecting empty space within atomic nuclei and between atoms.