They found that the universe is approximately 13.73 billion years old, and currently consists of 4.6 percent ordinary baryonic matter (atoms), 23 percent dark matter, and the remaining 72 percent consists of the mysterious dark energy, and less than 1 percent neutrinos.
This is cool because almost everything, most our theories and observations, all come from that 4.6%, it's only recently that stuff like this has started to be concerned with the other 95.4% of the universe.
Anyway, cool article that I wanted to share.
__________________ Uncertainty is an uncomfortable position.
But certainty is an absurd one.
Dark energy accounts for 72 percent of the mass of the universe, and also accounts for the observed acceleration of expansion. Like dark matter, it's not really known exactly what it is yet, it could be an intrinsic property of space itself.
Dark energy accounts for 72 percent of the mass of the universe, and also accounts for the observed acceleration of expansion. Like dark matter, it's not really known exactly what it is yet, it could be an intrinsic property of space itself.
Dark energy is the scientists' way of saying, "we don't know why the universe behaves the way it does, but we know that we can only account for 28% of its behaviour so we'll invent a term for the other 72%."
Yeah pretty much.. but that describes quite a bit of science, often they know the effects of what they are looking for before they actually find what it is.
It's like detecting a planet by the changes in the orbits of other planets, or knowing that a particle must exist long before it's finally detected; happens all the time. Otherwise experimentation would be random rather than directed.
The dark energy is there, we just don't know what it actually is.
__________________ Uncertainty is an uncomfortable position.
But certainty is an absurd one.
I wasn't aware they were sure how big the universe was, therefore, how would they know what makes up the parts they cannot see?
Just curious.
The cosmic background radiation is the signature of the big bang; it's a view of the universe as early as is possible with electromagnetic radiation. Any earlier and the universe was opaque. If we could detect gravity waves (if they even exist) we could peer back further, but I don't think they've done that yet.
With this cosmic background radiation they are able to tell how big the universe is, and the signature gives the variation of the stuff in the universe, so no need to directly observe every part of the universe.
__________________ Uncertainty is an uncomfortable position.
But certainty is an absurd one.
Dark energy is the scientists' way of saying, "we don't know why the universe behaves the way it does, but we know that we can only account for 28% of its behaviour so we'll invent a term for the other 72%."
That 28% is significantly smaller than it sounds when you consider that humans are limited by about 5 primary senses that allow us to interact with our natural environment, and a human brain which that the complexity of is vastly lower than the complexity of the universe. There is probably a lot more going than we'll ever be able to know or understand.
Sure, some of our senses can be expanded with technology, for example; increasing band of wavelengths of radiation that we can sense, but it's still small change.
I'd argue that the sample size for what we can view and extrapolate is insignificant based on our limited interaction with the natural environment.
__________________
"A pessimist thinks things can't get any worse. An optimist knows they can."
These stats come from the scientific theories on how the universe works. For their theories to work, there needs to be much more mass in the universe then they can see that there is. So, they try to find this dark matter/dark energy that the theories say must be there.
It's facinating and totally amazing that we have so much to learn yet about our universe. And the more we learn, The more we'll find that there are things that we do not yet know.
I hate to say it, but its about as reasonable/accurate as: "Mysterious Dark Energy."
Whats mysterious about it? What makes it dark? Energy is colour co-ordinated?
I think people are just going to call it whatever they want. Whos to say they're wrong until this inexplicable mystery is all cleared up?
No actually it's not at all.
Saying it's "God's energy" is making an epistemic claim. Saying it's just some generic "dark energy" is not making an epistemic claim.
Really, not similar at all.
And oddly enough, in some ways energy is colour coordinated. The energy (or wavelength or frequency) of a photon is what determines its "colour". Of course this description is anthropocentric, because colour is nothing more than a human construct. But this obviously has nothing to do with why they call it dark energy.
Dark energy, often called the "cosmological constant" or "lambda" (because of the letter used to denote it in the cosmological literature), was first "discovered" by Einstein. It is called dark because we can't detect it through conventional means. Don't get tripped up in the nomenclature. Astronomers have all sorts of weird names and naming conventions.
If you want to actually learn about this stuff, read the wiki article. If you have any questions, I'm more than happy to answer them.
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"For thousands of years humans were oppressed - as some of us still are - by the notion that the universe is a marionette whose strings are pulled by a god or gods, unseen and inscrutable." - Carl Sagan Freedom consonant with responsibility.
Matter makes up only 4.6% of the universe!
