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Why did dark energy overcome dark matter to create the expanding universe we live in today?
It didn't.Why did dark energy overcome dark matter to create the expanding universe we live in today?
It's just not at all true that dark matter and dark energy are opposing forces that were close in strength. And Einstein certainly never said it (as the term dark energy wasn't coined until after his death).
Einstein's original idea of a cosmological constant was conceived because Einstein thought the universe should be static. He used the cosmological constant to balance the matter (dark matter wasn't known at the time, either). The idea there was that matter tries to fall inward, causing the universe to collapse. The cosmological constant pushes outward. So if you have a matter density and cosmological constant that are perfectly-balanced, then you can have a universe that neither expands nor contracts.
The problem with this idea, besides just being incorrect, is that it is unstable: a universe sitting in this configuration is just at the boundary of collapsing into a singularity or expanding forever. All it needs is for a little bit of matter in one region to migrate to another, and the whole system destabilizes.
So this idea of dark energy balancing dark matter was never a viable model. It wasn't a good idea to begin with, and it certainly never described our universe.
Einstein didn't come up with the idea of dark matter, he came up with the cosmological constant previously mentioned. That'd be dark energy. And you are completely forgetting inflation.
You've still got a rather confused notion of what dark matter and dark energy do.I don't care how good of a model it is or isn't to another person, that is irrelevant as well. The fact is that Dark Matter has a small impact on the universe where as Dark Energy has a significant impact. In these terms they could be considered to have opposites properties, although technically not opposite forces I suppose.
All I know is that at some point in the beginning of the big bang, Dark Matter and Dark Energy had opposite properties which affected the universe to expand. The properties contained with Dark Matter and Dark energy are dynamic and unfixed.
It's entirely relevant, because your question makes no sense at all when applied to our universe.By the way, this is a theory and not a statement demanding to be a fact. Nothing can be proven wrong or right. "Incorrect" is irrelevant.
Neither dark energy nor dark matter is responsible for the fact that the universe is expanding.
I thought dark energy was, in the form of the cosmological constant
relativity implies that time's passage is a chimera... all that is real is the whole history of the universe laid out at once? That point of view, the block-universe perspective, led Albert Einstein to declare in a letter to the family of his friend Michele Besso that the "distinction between past, present, and future is only a stubbornly persistent illusion."
One of space's properties is that it can expand, and that means it contains Dark Matter
dark energy lets space expand
But Dark energy allows for it and this is one case. But how can space expand without dark energy or the cosmological constant? And I meant Dark Matter, it was a typo, by the time you read this I would have fixed it.This is not correct; the expansion of space does not require dark matter to be present.
This is not correct either; space can expand without dark energy being present.
how can space expand without dark energy or the cosmological constant?
Dark energy and dark matter influence how expansion changes over time. But a universe can easily expand (or contract) with either, given the right initial conditions.But Dark energy allows for it and this is one case. But how can space expand without dark energy or the cosmological constant? And I meant Dark Matter, it was a typo, by the time you read this I would have fixed it.
dark energy has the lowest density
Volume determines expansion.
Think of an air balloon.
What determines how big the balloon is; the volume of air.
This is incorrect and very confused. Sean Carroll made a blog post a little while ago that does a good job of explaining how dark energy relates to the expansion of the universe:Very simply because dark energy has the lowest density and the most volume/quantity.
Volume determines expansion.
Think of an air balloon.
What determines how big the balloon is; the volume of air.