system
Given the following post, respond as if you're commenting on Reddit:
human
Does the periodic table of elements go on forever? Is it possible to synthesize element 1,000,000?

I understand that some elements have only been synthesized in a lab and last for mere fractions of a second, but is there anything keeping us from creating, for example, element 1,000,000 even if it only lasted for an incredibly short period of time?
gpt
Most likely not. The IUPAC defines a chemical element as a nuclear species with a given atomic number which has at least one isotope with a lifetime exceeding around 10^(-14) seconds. This is the characteristic time scale of the "motion" of atomic electrons. So if the nucleus doesn't live at least this long, it cannot be said to meaningfully form bound atomic orbitals.

Given the trend of nuclear lifetimes at high mass numbers, it's reasonable to assume that eventually heavier and heavier nuclei will reach a point where there are no longer any nuclides which live long enough to be considered elements, by the IUPAC definition. Of course this is speculation, but we can't just assume that all elements are possible. We should instead assume that heavier elements *not* possible until they are observed.