so what effect does dark matter have on planets WITH a star???
Posted on 04/02/2011 6:24:09 PM PDT by LibWhacker
(PhysOrg.com) -- In a resent paper posted at arXiv.org and submitted to Astrophysical Journal, Dan Hooper and Jason Steffen, physicists at Fermilab in Illinois, present the theory that cold and dark planets, not heated by a star, could be heated by dark matter. In theory, this dark matter could produce habitable planets outside of what is known as a habitable zone.
While no one knows exactly what dark matter is, it is believed to make up about 83 percent of the universe. The most accepted theory is this dark matter is made up of what are called WIMPs, or weakly interacting massive particles.
These WIMPs interact with regular matter by a weak nuclear force and gravity, but they are also antiparticles. When two WIMPs come together, they work to annihilate each other and cause a burst of energy.
Hooper and Steffen suggest that should this dark matter be trapped within a planet’s gravity, the bursts of energy could produce enough to warm the planet. When it comes to Earth, the energy that could be produced is low, but in areas of space where there are high densities of black matter; Hooper and Steffen believe there is the possibility of finding planets that could be warmed in this way.
Within the innermost regions of the Milky Way, density of dark matter is estimated to be hundreds or thousands of times that in our solar system, and it is in these areas that Hooper and Steffen believe finding a planet heated by dark matter would be most plausible.
Traditional planets, heated by stars like our sun, are dependent on the life of that star. This theory would make these dark matter planets have a large advantage over those tied to a star, as the dark matter could provide heat for trillions of years.
Hooper and Steffen admit that they currently do not see a way of detecting any of these possible dark matter planets in the near future, but that in theory, it is possible.
2. From such a mass? In principle, escape velocity is given by Ve=sqrt(2GM/r). I think someone lifted my old HP41C calculator, so I'll let you work it out. But note that that is only the escape velocity in principle. In actuality, you can't escape the universe by going fast. Not even light can do that. It's like being inside a black hole.
3. There is no center. Is there a center of the surface of a ball? No. The surface has no center.
4. I think this is possible. Any black hole will do. (Don't quote me on that!)
5. Light can't escape. The universe is a singularity. But there are lots of wonderful and bizarre ideas floating around out there; e.g., that beyond the observable universe, the rest of the universe is speeding away from us faster than the speed of light. So maybe there are photons in this universe that are zipping away in a straight line and that aren't following any kind of curved path?
Plasma / aether, same thing. The mixture is actually about 50/50 (plasma/matter) and the plasma/aether doesn't have a mass, but overall I agree with you.
“When two WIMPs come together, they work to annihilate each other and cause a burst of energy. “
Sounds like a lot of marriages.
Here’s a question just for you:
Why is it dark at night?
(this is not a joke question, it is a real one and the answer isn’t simple or obvious)
so what effect does dark matter have on planets WITH a star???
Isn't that what the concept of a black hole is about?
The Schwarzschild radius is that particular 'orbit' around a black hole where light would appear to be in an orbit.
Who knows if black holes exist, or conform to our theory of them.
We cannot even visualize what a spherical black hole in space would really even look like. A black hole cannot be the FLAT CIRCULAR image that we are treated to by our scientists. But that is the only way we can conceive the subject of the theory.
Well... yes.
You specified a ball (sphere) and a surface, ergo it must have a center.
Now, the Universe is not a Sphere, so your argument for something that doesn't exist doesn't hold.
I am now thoroughly confused.
Seems to me that if dark matter could produce 'heat', we could see it, because most of our imaging these days is from radio waves and INFRARED.
Of course, there is then the further theory of 'dark energy'. Maybe it produces HEAT that can't be seen.
I heard you could get slightly used quarks from another dimension, on EBAY.
a blackhole would be about the only thing that can bend light that much, and then, only to the event horizon...???
A sphere certainly does have a center. Why all the focus placed upon the surface alone?
To demonstrate that there are spaces that have no center. They exist. The universe is like that. You see the same kind of point made when people talk about things like "finite but unbounded." The surface of a sphere is finite in size, but you'll never run into a wall or boundary, no matter how much you travel around on the surface. In some cosmologies, the universe is finite but unbounded. So it's very much like the surface of a sphere. Except it's three dimensional.
The universe has volume, correct? The surface of a sphere, finite but unbounded though it may well be, encompasses volume. The surface is two dimensional. The volume the surface of the sphere encompasses is three dimensional, and this represents the whole object.
We're just looking at the surface in isolation of the space it curves around and encloses. The surface has no center. The three-dimensional ball has a center, but that's not what we're talking about.
There are two-dimensional spheres, three-dimensional spheres, etc. The surface of an idealized basketball, say, is two-dimensional. A 2-D bug on the surface can move right and left, or forward and backward. But that's it. He can't move up and down. There are no stairs or mountains in his world. He lives in a 2-D world. The universe may be like that, except it's a 3-D world, curved in some 4th dimension that we cannot perceive. It has no center.
Yes. It is a three-dimensional space, so it must have a volume. But the analogy to a two-dimensional spherical surface is a good one. This is what happens when you generalize a notion in mathematics. It can definitely stretch the old gray matter.
This is all part of a branch of mathematics called topology. I've never taken a course in it, but I've encountered plenty of theorems from topology and it can be very tough conceptually. Every step can be a struggle. One approach that I used to take was to say, "Okay, for some bizarre reason you want to talk about your weird little two-dimensional closed surfaces that have no centers... Sock it to me! I'm game."
Your questions are the same ones asked by Isaac Asimov. His conclusion was that our Universe itself is a giant black hole.
That pretty much sums it up. I would add, though, that “dark matter” was postulated to explain some inconsistencies between the Theory of Relativity and observations. The “missing mass” hypothesis has the math to make it worth, but it hasn’s been adequately tested through observation.
Actually, the key is energy in any form. There are a lot of lifeforms that do quite nicely here on earth in total darkness- the anaerobic bacteria found in undursea volcanoes derive all the energy they need from head and chemical reactions.
Yes and there are species that do quite nicely on earth in extremely cold weather also, that doesn’t change the fact that more species thrive in warmth and light than do in the cold and dark.
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