4 ms·
The Expansion oft the universe would cause a slow increase in wavelengh over time
by dtx1 4y ago
The Expansion oft the universe would cause a slow increase in wavelengh over time
- dvsfish 4y agoDoes this mean that the notion of conservation of energy is actually preserved? Everywhere says its not except on local scales but this almost sounds like dark energy/the creation of more space is fuelled by light.
- andrewflnr 4y agoEnergy conservation is... tricky. Under Noether's Theorem it's guaranteed by time translation symmetry, which is kind of sketchy at cosmological scale. My understanding is that it can be violated under conditions of changing gravitational fields or somesuch, but don't really understand what specific circumstances do the trick. Ed: don't get hung up on "expansion of space is fuelled by light" or whatever, they only picked a photon for their thought experiment because it was easy to reason about.
- 9991 4y agoThe total “energy” of all photons in the universe is declining, but the acceleration is increasing. Hard to believe the first is causing the second.