- #1
narrator
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Expansion "speed" and accelleration question
I was reading about how the OU was once the size of a grapefruit, which prompted me to think about expansion acceleration.
At the time that the OU was the size of a grapefruit, the universe had to be expanding faster than light, otherwise the OU would have been bigger than a grapefruit (Hubble et al).
Step forward some billions of years and the OU is as we now know it, with the universe expanding faster than light... and accelerating.
This led me to think that there are one of three possibilities:
1. Expansion did not accelerate for an unknown period sometime between the grapefruit and now, leaving current expansion at perhaps a little faster than it was during the grapefruit era, or
2. If it has accelerated ever since the time of the grapefruit, then either that acceleration is so miniscule as to be hundreds of decimal places, or
3. If it has accelerated ever since, and not at a miniscule rate, then the current velocity due to expansion (not from ordinary movement) has to be in the order of many many time light-speed.
Am I missing something?
I was reading about how the OU was once the size of a grapefruit, which prompted me to think about expansion acceleration.
At the time that the OU was the size of a grapefruit, the universe had to be expanding faster than light, otherwise the OU would have been bigger than a grapefruit (Hubble et al).
Step forward some billions of years and the OU is as we now know it, with the universe expanding faster than light... and accelerating.
This led me to think that there are one of three possibilities:
1. Expansion did not accelerate for an unknown period sometime between the grapefruit and now, leaving current expansion at perhaps a little faster than it was during the grapefruit era, or
2. If it has accelerated ever since the time of the grapefruit, then either that acceleration is so miniscule as to be hundreds of decimal places, or
3. If it has accelerated ever since, and not at a miniscule rate, then the current velocity due to expansion (not from ordinary movement) has to be in the order of many many time light-speed.
Am I missing something?