Just a thought--if 'the universe is expanding' (red shift/dark energy), that is identical to 'everything in the universe is shrinking'.
'Everything' including the size of every atom, bringing Uranium atoms closer together, causing more chain reactions, lowering critical mass. In a billion years every nuke might spontaneously detonate.
Inspect your Uranium. I'd bet the half-life has changed since originally measured 90 years ago.
That's what was tripping me out. Your house would expand into your yard. The universe allegedly isn't expanding into anything.
They show it in demonstrations like a balloon stretching. The rubber itself getting larger. They'll polka-dot a balloon and show how the dots get further apart when it's inflated.
But in the demonstration the dots of permanent market also get bigger and stretched. If we're expanding along with the universe, we shouldn't notice it. (A 10' fence is double the height of a 5' woman, and if both expand by 2x, a 20' fence is still double a 10' woman) This isn't what we observe. Instead, gravity and strong/weak forces keep our matter falling inward to stay the same size as the space grows through us.
This necessary inward falling, along with the assertion that space is increasing in the rate of expansion is what had me worried of nuclear chain reactions.
Though I'm clearly 100% backwards, and increasing the amount of new space between particles would decrease the incidence of chain reactions. Critical mass would be getting more difficult to reach and today's nukes will eventually become nonfunctional.
Tldr: sorry and thanks
I'm not a subject matter expert, nor anything close
a search came up with
No, you are not expanding along with the universe. The expansion of the universe refers to the increase in distance between gravitationally unbound parts of the observable universe over time [1]. This means that galaxies are moving away from each other, but objects within those galaxies, like stars, planets, and people, are not expanding because they are bound by local gravity [1][2]. The expansion is happening on a cosmic scale, and it doesn't affect the size of smaller, gravitationally bound systems like the human body, the Earth, or the Solar System.
Citations:
[1] https://en.wikipedia.org/wiki/Expansion_of_the_universe
[2] https://www.loc.gov/item/what-does-it-mean-when-they-say-the-universe-is-expanding/
[3] https://www.space.com/52-the-expanding-universe-from-the-big-bang-to-today.html
[4] https://www.npr.org/sections/13.7/2017/05/24/529675773/what-does-an-expanding-universe-really-mean
[5] https://skyserver.sdss.org/dr1/en/astro/universe/universe.asp