Science & Technology Q&A for Kids (and others) [May 12, 2023]

Stephen Wolfram answers general questions from his viewers about science and technology as part of an unscripted livestream series, also available on YouTube here: https://wolfr.am/youtube-sw-qa Questions include: Why is it important that the periodic table is structured as a table rather than a list of elements? - Is the periodic table just the table for the current state? Since there weren't heavy atoms from the start (Big Bang), maybe in the far future everything decays and just the electrons survive. - How certain are we that the Big Bang actually happened? What are the chances of the Big Bang theory being displaced in the future? - What do you make of the very early galaxies seen by JWST, which seem too large to exist so early? - Is it possible that the expansion of space due to dark energy could eventually be fast enough that even atoms and nuclei come apart? - How is the temperature of cosmic background radiation measured? Is it just from the wavelength of the microwaves?