71–80 of 104 posts
Interesting, could a physical system exploit differences in the rate of expansion? What happens to an object as it moves from a high rate-of-expansion region to a low rate-of-expansion region?
But what is it expanding into? If the universe is expanding like a balloon then there's some sort of "edge". What is that edge expanding into? Imagine we had a craft that could take us to the edge and you could stand on it, the way you place your finger on the outside of a balloon. If you could stand on the outside/edge of the expanding universe, what would you see, that we're expanding into? It can't be nothing. Som…
Cosmology feels a lot like quackery these days. Does it even bother to rely on physics? Physical experiments show explosions do not propel all matter at the same rate. James Webb telescope recently found galaxies that were “too old”, would have formed right after the Big Bang. The prevailing wisdom was all matter spread out evenly due to the Big Bang, then coalesced into galaxies (I emailed various researchers to con…
Attempting to work backwards to the beginning of the universe from a single tiny point in time and space is fairly obviously going to be a lot harder than understanding the physics of events we can repeat, measure, and examine. This doesn't make them quackery and it does explain why many things remain poorly explained. A century from now its likely that many understandings will be retained and some will have been consigned to the bin.
People do challenge existing theories. Most frequently unsuccessfully. Because most novel hypothesis turn out to be wrong.
Riffing off the science fiction reference this isn't a process we can skip any more than authors can skip brainstorming, first drafts, rewrites and just skip to typing out the final draft.
In brief stop coming off like Agent Mulder. Everyone knows the truth is out there. If it takes a while to coalesce its not because the educated folks working on the problem too stupid to listen to basic physics. It's because the physics that explains the rest of the picture isn't written yet.
Earlier quoted context omitted.
> The expansion of universe is accelerating. We knew that before. This goes deeper than that. It accelerates in a way that cannot be explained by a constant dark energy density, which is part of our standard model. We have plenty of alternative models that can explain this, but our measurements are not precise enough yet to rule any of them out. Hopefully Euclid will provide data that is.
If expansion at the big bang started with a rate of X. Could the varying densities at different points cause their expansion to deviate from the original rate?
The spatial inhomogeneities of matter in the very early universe, which I believe you might be talking about, were extremely tiny.
But what is it expanding into? If the universe is expanding like a balloon then there's some sort of "edge". What is that edge expanding into? Imagine we had a craft that could take us to the edge and you could stand on it, the way you place your finger on the outside of a balloon. If you could stand on the outside/edge of the expanding universe, what would you see, that we're expanding into? It can't be nothing. Som…
Earlier quoted context omitted.
> explosions… explosions What are you drawing an analogy to explosions with in this comment? The Big Bang? Why do you expect the analogy to be as precise as you seem to take it to be?
Because researchers put on emotional costumes to serve how they pay for food and shelter, spend their time defending crap results for years/decades. Let’s not pretend the replication crisis isn’t real and endemic within academia these days.
But what is it expanding into? If the universe is expanding like a balloon then there's some sort of "edge". What is that edge expanding into? Imagine we had a craft that could take us to the edge and you could stand on it, the way you place your finger on the outside of a balloon. If you could stand on the outside/edge of the expanding universe, what would you see, that we're expanding into? It can't be nothing. Som…
If we were somehow able to accelerate a particle out past the edge of the known universe, now the bubble includes that particle too and essentially we've 'expanded' the universe. In other words, the arbitrary bubble containing things that we know about and consider significant is larger than it was before - because there's something out there we can observe.
But what is it expanding into? If the universe is expanding like a balloon then there's some sort of "edge". What is that edge expanding into? Imagine we had a craft that could take us to the edge and you could stand on it, the way you place your finger on the outside of a balloon. If you could stand on the outside/edge of the expanding universe, what would you see, that we're expanding into? It can't be nothing. Som…
In this case it's entirely possible for the topology of space to change such that it takes longer to travel from one point to another over time. If you consider a trip from point A to point B in topology A, and then topology A expands during the trip from point A to point B such that new distance is created, then the "distance" you have to travel to get to B is changing because at each moment along the trip you're at a different point.
If you think about it this way, the universe can be both expanding because it takes progressively longer to get from point A to point B, and it can also not be expanding into some "outer" area because there's nothing other than the universe.
It may make more sense to stop thinking in terms of distance and start thinking in terms of time. In that case, when you think of "expansion" what you're really describing is that at a constant speed, the closer you get to B, the more time it takes you to advance toward B. And if you change direction mid-trip to go to C, the "expansion" means that the amount of time required to reach C also increases as time elapses.
It's hard to say what's causing that expansion, but we can measure it by its effects on light traveling the same distance.
Earlier quoted context omitted.
> The expansion of universe is accelerating. We knew that before. This goes deeper than that. It accelerates in a way that cannot be explained by a constant dark energy density, which is part of our standard model. We have plenty of alternative models that can explain this, but our measurements are not precise enough yet to rule any of them out. Hopefully Euclid will provide data that is.
I can explain it with higher dimensional turbulence. Where is my Nobel.