How Do We Know Dark Matter Exists
Imagine the Universe was a pie, and you were going to slice it up into tasty portions corresponding to what proportions are what. The largest portion of the pie, 68% would go to dark energy, that mysterious force accelerating the expansion of canada goose outlet in new york the Universe. 27% would go to dark matter, the mysterious matter that surrounds galaxies and only interacts through gravity. A mere 5% of this pie would go to regular normal matter, the stuff that stars, planets, gas, dust, and humans are made out of.
Dark matter has been given this name because it doesn’t seem to interact with regular matter in any way. It doesn’t collide with it, or absorb energy from it. We can’t see it or detect it with any of our instruments. We only know it’s there because we can see the effect of its gravity.
canadian goose jacket Now, you might be saying, if we don’t know what canada goose outlet montreal this thing canada goose sale uk is, and we can’t detect it. How do we know it’s actually there? Isn’t it probably not there, like dragons? How do we know dark matter actually exists, when we have no idea what it actually is? canadian goose jacket
cheap Canada Goose Oh, it’s there. In fact, pretty much all we know is that it does exist. Dark matter was first theorized back in the 1930s by Fritz Zwicky to account for the movement of canada goose outlet seattle galaxy clusters, but the canada goose outlet las vegas modern calculations were made by Vera Rubin in the 1960s and 70s. She calculated that galaxies were spinning more quickly than they should. So quickly that they should tear themselves apart like a merry go round ejecting children. cheap Canada Goose
Rubin imagined that canada goose outlet london uk every galaxy was stuck inside a vast halo of dark matter that supplied the gravity to hold the galaxy together. But there was no way to actually detect this stuff, so astronomers proposed other models. Maybe gravity doesn’t work the way we think it does at vast distances.
Canada Goose Online But in the last few years, astronomers have gotten better and better at detecting dark matter, purely though the effect of its gravity on the path that light takes as it crosses the Universe. As light travels through a region of dark matter, its path gets distorted by gravity. Instead of taking a straight line, the light is bent back and forth depending on how much dark matter is passes through. Canada Goose Online
Canada Goose sale And here’s the amazing part. Astronomers can then map out regions of dark matter in the sky just by looking at canada goose outlet uk fake the distortions in the light, and then working backwards to figure out how much intervening dark matter would need to be there to cause it. Canada Goose sale
Canada Goose online Large Hadron Collider. Credit: NY TimesThese techniques have become so sophisticated that astronomers have discovered unusual situations where galaxies and their dark matter have gotten stripped away from each other. Or dark canada goose uk site matter galaxies which don’t have enough gas to form stars. They’re just giant blobs of dark matter. Astronomers even use dark matter as gravitational lenses to study more distant objects. They have no idea what dark canada goose outlet new york matter is, but they can still use it as a telescope. Canada Goose online
buy canada goose jacket They’ve never captured a dark matter particle, and haven’t studied them in the lab. One of canada goose jacket outlet the Large Hadron Collider’s next tasks will be to try and generate particles canada goose outlet england that match the characteristics of dark matter as we understand it. Even if the LHC doesn’t actually create dark matter, it will help narrow down the current theories, hopefully helping physicists focus in canada goose outlet 2015 on the true nature of this mystery. buy canada goose jacket
uk canada goose outlet This canada goose stockists uk is how science works. Someone notices something unusual, and then people propose theories to explain it. The theory that best matches reality is considered correct. We live in a modern world, where so many scientific theories have already been proven for hundreds of years: germs, gravity, evolution, etc. But with dark matter, you’re alive at a time when this is a mystery. And if we’re http://www.mycanadagoosejacket.org lucky, we’ll see it solved within our lifetime. Or maybe there’s no dark matter after all, and we’re about to learn something totally new about our Universe. Science, it’s all up to you. uk canada goose outlet
canada goose uk black friday What do you think dark matter is? Tell us in the comments below. canada goose uk black friday
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cheap canada goose uk 2) canada goose outlet There isn near enough matter or dark matter to make the universe canada goose outlet orlando flat. So there must be something else. cheap canada goose uk
3) the rate of expansion of space between galaxies has been increasing since (I don remember) 2 billion after the bang So somehow whatever is making the universe flat makes it expand?
canada goose factory sale I sensing lack of coherence on the matter. canada goose factory sale
Take the example of Ptolemy and Hubble maybe aren not just the center of the solar system, or the canada goose outlet in toronto galaxy, or of all space, but maybe what we see and feel isn the center plate of existence. Maybe we just a fringe element.
Canada Goose Jackets Of course we are on the fringe of existence. Think of a bomb going off. Everything is blown out from the center. We are on one of these pieces of the Universe that has been blasted out from the center of the Universe. Canada Goose Jackets
canada goose coats on sale What is causing the Universe to expand constantly faster? This is an easy explanation and cause without bringing in exotic terms. First, you need to study explosions. They occur in two parts. The explosion that leaves the epic center in an absolute void. And the collapse of matter back canada goose outlet black friday into the center. This happens in all explosions even the big bang. canada goose coats on sale
What we are seeing is not the acceleration of the Universe expansion. What we are seeing is the Universe collapsing into the center. The strongest pull is being delivered to galaxies nearest the center. Special relativity canada goose outlet nyc would make it look from our perspective as just as everybody thinks, the Universe accelerating in it expansion. We simply see too small of the section of the pie to see this. We also are seeing too small of a time frame to verify whether this is true or false. To us, everything is drifting away. This is as you would expect. But as galaxies closer to the center decelerate it looks to us as they are accelerating away from us. As our galaxy decelerates, it looks as if galaxies further away from the center are accelerating away from us. Galaxies at the same distance from the center look like they are accelerating from us too as they were launched from the initial big bang explosion at a different angle. canada goose outlet in usa And the distances will look like they are expanding.
So relax people. The Universe is behaving exactly as predicted it should react. There is no secret energy out there that is accelerating our expansion. Think of this: Can you see or measure centrifugal force? No. It can be predicted from laws that we already know. So can the expansion/contraction of the Universe.
No, no, no. When we look back say 5,000,000,000 years to a galaxy, we see exactly 5,000,000,000 years. We don see the exact same galaxy at 5,100,000,000 years. Now when we look back closer to the big bang say 13,000,000,000 years at a galaxy. We see that galaxy at 13,000,000,000 years. We don see that galaxy at 13,100,000,000 years. In other words, we don see movement or enough movement to make certifiable predictions of what is actually happening.
And of course the Big Bang was an explosion. It was on such a massive scale that our minds just can comprehend what happened. But if it walks like a duck and talks like a duck, it must be a duck. When all the energy in the universe came into existence from one sub plank length object (very small indeed) at that time everything behaved exactly as an canada goose outlet germany explosion should behave. The shock wave expanded outwards setting the boundary of the known Universe. The force of that blast was so huge that it propelled the shock wave faster than the speed of light. As the energy of canada goose outlet price the original blast diminished, so did the velocity of the shock wave. After billions of years, the edge of the Universe (the shock wave) is finally coming to a halt. It not stopping because of friction. It stopping because the Universe behind it is stopping and the leading edge is being draw official canada goose outlet back into the Universe. What outside of the Universe (beyond the shock wave) is anybody guess. Could be an absolute void with no radiation at all. Could be some type of plasma. Could be almost anything. But what is certain is the center of the explosion canada goose outlet ontario is an absolute void which must be filled. And the galaxies closest to that void are going to fill it first. The galaxies at the farthest edges of the explosion might have reached escape velocity and will never come back. And we are somewhere in the middle without knowing what our fate will be. Are we close enough to the big bang center to be drawn back into it? Did we reach escape velocity? Or are we going into orbit around some canada goose outlet kokemuksia yet canada goose outlet paypal undiscovered grand father of a black hole that is holding the Universe together?
Canada Goose Parka Because of special relativity any number of outcomes could be possible and we will never truly know it Canada Goose Parka.