3 ms·

'space' isnt a substance that can move at any speed. What's meant by the claim that 'space moves faster than light' is that extremely distant objects are movin

'space' isnt a substance that can move at any speed. What's meant by the claim that 'space moves faster than light' is that extremely distant objects are moving away from each other, relative to each other, 'faster than light' -- which is permitted, so long as that distance can never be bridged by light. The claim amounts to, in other words, that the universe is so large that we can compare objects at distances greater than those light could travel between them, and if we do that, they travel faster than light. This is an "illusion in measurement" more than anything else. Nothing is travelling faster than light.

TechBro8615 3y ago
Here's an article that explains this distinction in detail: https://medium.com/the-infinite-universe/why-galaxies-receding-faster-than-the-speed-of-light-are-still-visible-664ff21f0829 https://medium.com/the-infinite-universe/why-galaxies-recedi...
rkagerer 3y ago
So it can't fold on itself and form a wormhole that bridges light?
gpderetta 3y ago
> space moves faster than light I think this simply refers to the metric expansion of the universe [1]. While nothing actually travels FTL, the distance between some objects really expands faster than FTL and is not an illusion. [1] https://en.m.wikipedia.org/wiki/Expansion_of_the_universe https://en.m.wikipedia.org/wiki/Expansion_of_the_universe
- mjburgess 3y ago
  The illusion is the impression that something moves faster than light. 'distances' arent literally 'expanding' -- this metaphor of expansion describes a shift in the matter distribution of the universe over time which seems like an expansion of an underlying substance 'space'. This is the illusion. The metric is just that matter distribution. And the fact of its changing we call 'expansion'. This metaphorical, substantival language, creates a lay impression that some physical object moves faster than light.

TechBro8615 3y ago

Here's an article that explains this distinction in detail: https://medium.com/the-infinite-universe/why-galaxies-receding-faster-than-the-speed-of-light-are-still-visible-664ff21f0829 https://medium.com/the-infinite-universe/why-galaxies-recedi...

rkagerer 3y ago

So it can't fold on itself and form a wormhole that bridges light?

gpderetta 3y ago

> space moves faster than light I think this simply refers to the metric expansion of the universe [1]. While nothing actually travels FTL, the distance between some objects really expands faster than FTL and is not an illusion. [1] https://en.m.wikipedia.org/wiki/Expansion_of_the_universe https://en.m.wikipedia.org/wiki/Expansion_of_the_universe

mjburgess 3y ago
The illusion is the impression that something moves faster than light. 'distances' arent literally 'expanding' -- this metaphor of expansion describes a shift in the matter distribution of the universe over time which seems like an expansion of an underlying substance 'space'. This is the illusion. The metric is just that matter distribution. And the fact of its changing we call 'expansion'. This metaphorical, substantival language, creates a lay impression that some physical object moves faster than light.