First observational evidence linking black holes to dark energy
First observational evidence linking black holes to dark energy
Sounds promising. can't say I understand all the details.
This is craaaazy astronomical news if true! I'll try to summarize from my limited understanding as I'm not a professional.
First of all, this article is about Dark Energy, at it's basics Dark Energy is an unknown force which is why it's called "dark" and it was named after scientists couldn't explain why the universe (or spacetime specifically) was expanding as quickly as it is. This paper is the first piece of observational evidence that might "shed some light" on where Dark Energy comes from. From what I can gather, it says that through observing lots of supermassive black holes at the center of loads of galaxies, they've determined two things if this observation is correct: black holes don't have a singularity at their cores, and that black holes gain mass by "cosmological coupling" as they put it.
First, a singularity means that math breaks down, it usually means that it tends toward infinity and the equation can't be solved. With black holes, it usually means that spacetime itself collapses down infinitely into a single dimension, which is pretty hard for us to understand and breaks a lot of physical laws like Einstein's equations.
Second, "cosmological coupling" they explain is that as the space expands, the black hole also expands. In very simple terms, lets say the black hole has a diameter 2 LY (light years) in space. If after say a million years space expands enough that 2 LY now is equivalent to 1 LY before then the size of the black hole is essentially 4 LY now when using the old universe's definition of what a LY is.
Edit: I forgot to mention that because the black hole is essentially "absorbing" spacetime it must gain energy because spacetime does have energy even though we consider it "empty".
Because of Einstein's famous equation e=mc^2 we can determine that energy is basically equivalent to mass, and since the black hole is getting extra energy from this "cosmological coupling", it's also gaining mass.
I think the most basic TL;DR I can give then is: black holes are sort of "absorbing" spacetime as it expands and gaining energy while doing so which in turn leads them to gaining mass. This extra mass has now been shown through observation to account for and completely explain the origins of Dark Energy.
With that said... THIS PAPER IS BRAND NEW AND HAS NOT BEEN PEER REVIEWED! This is not a discovery yet, it's way too early to say anything conclusive.
It's too early on a Saturday morning for me to comprehend this paper. I'm going back to figuring out AWS.
This extra mass has now been shown through observation to account for and completely explain the origins of Dark Energy.
Thank you for explaining! I followed you right up to the quote above How does the extra mass account for and completely explain dark energy?
I'm going to take a guess because again I'm not an astronomer or a physicist, just a lay person and an enthusiast.
What Dark Energy does can basically be boiled down to anti-gravity. It's not exactly that, we're not really sure what it is, but that's what effect it has, it's repulsive in the same way that gravity is attractive. The theory is that space is expanding and the more space between things (like galaxies) the faster they will move away from each other. It's also been getting faster since the Big Bang.
We also assumed that black holes didn't gain much mass unless they absorbed a large body of matter or had an accretion disk -- They do gain mass through Hawking Radiation but that's pretty minuscule. So I think this study has to do with the distribution of matter throughout the universe and the amount of matter in galaxies.
If black holes have always been as massive as they are today then we would assume that everything would be much closer together and the super massive black holes at the center of galaxies would have gathered more matter than they currently have. So we made the assumption that there must have been some kind of repulsive force that spread everything out. Instead the black holes had less gravitational force than we assumed and so it explains why they didn't gather more matter into their orbits and everything spread out across the universe in the way we observe it today.
Again, I'm just guessing based on my limited knowledge. If an astronomer wants to jump in here, please do!
Wikipedia's blackhole is expanding. further reading; Supermassive