Yes, all distances are expanding, but not everything in space is expanding. Atoms aren’t expanding because atomic forces are far stronger than expansion is, for example.
Yet the distance between galaxies is increasing, so there must be a crossover point where one structure can stay structured but a slightly bigger structure is torn apart.
My question was if this size is larger or smaller than galaxies, and it seems to be quite a bit larger than galaxies at the moment.
The interesting thing is that the expansion is increasing, so this size limit is shrinking. Unless some change in forses happens (like inflation or some kind of false vacuum collapse) the limit will eventually be smaller than galaxies and they’ll get ripped apart. Eventually star systems will be ripped apart too, then stars (if any remain at that point) then planets, molecules, atoms, and bosons; and if if that continues to quarks funny things start happening that kind of look like the big bang.
That last part is still speculation of course, but I do still wonder if the expansion of the universe affects galaxy formation and dynamics, and if ancient galaxies were different in part because of this.
So yes attoms are expanding. everything is expanding. I mean that very literally.
Let me put it this way.
If you had a million year old meter stick. It would always be a meter. Accurate to the definition of a meter using the wavelength of I don’t remember what off the top of my head. It would always be a meter exactly.
But.
If you magically placed the meter stick next to itself from a million years ago, they would not measure the same. Even though they started with the same definition.
Like I said. Space isn’t expanding. Distance is.
EDIT I don’t mean the distance between things is expanding. The definition of what a distance was is expanding. So yes, attoms, when measured by size (the distance from one edge to another) has also expanded.
But in the same breath, the measured distance never changes. Because the way you use to measure distance has also expanded by the same amount. So nothing ever changes in reality, but everything is just constantly bigger.
Yes, all distances are expanding, but not everything in space is expanding. Atoms aren’t expanding because atomic forces are far stronger than expansion is, for example.
Yet the distance between galaxies is increasing, so there must be a crossover point where one structure can stay structured but a slightly bigger structure is torn apart.
My question was if this size is larger or smaller than galaxies, and it seems to be quite a bit larger than galaxies at the moment.
The interesting thing is that the expansion is increasing, so this size limit is shrinking. Unless some change in forses happens (like inflation or some kind of false vacuum collapse) the limit will eventually be smaller than galaxies and they’ll get ripped apart. Eventually star systems will be ripped apart too, then stars (if any remain at that point) then planets, molecules, atoms, and bosons; and if if that continues to quarks funny things start happening that kind of look like the big bang.
That last part is still speculation of course, but I do still wonder if the expansion of the universe affects galaxy formation and dynamics, and if ancient galaxies were different in part because of this.
So yes attoms are expanding. everything is expanding. I mean that very literally.
Let me put it this way.
If you had a million year old meter stick. It would always be a meter. Accurate to the definition of a meter using the wavelength of I don’t remember what off the top of my head. It would always be a meter exactly.
But.
If you magically placed the meter stick next to itself from a million years ago, they would not measure the same. Even though they started with the same definition.
Like I said. Space isn’t expanding. Distance is.
EDIT I don’t mean the distance between things is expanding. The definition of what a distance was is expanding. So yes, attoms, when measured by size (the distance from one edge to another) has also expanded.
But in the same breath, the measured distance never changes. Because the way you use to measure distance has also expanded by the same amount. So nothing ever changes in reality, but everything is just constantly bigger.
Physics is full of hard to explain paradoxes.