How did current theory come up with a 85% of dark matter in the Universe?

Question

Where simple high shool calculation only Indicates that the substance of space called dark matter cannot exceed 52.359 per cent Of the total geometrical volume of the Universe?

If the theory of dark matter is correct the size of the Universe is immaterial .? The percent remains the same no matter what the size.?

Answer 1

It's kind of funny. There is a problem with a popular theory, so to keep it breathing, someone has to imagine a new thing you can't see.

Sometimes this actually works. The neutrino was invented to save another theory.

But astronomers have a much tougher problem to solve (can't drag the universe into a lab), so they need a little more slack. That said, dark matter remains suspiciously convenient. But then, they're still getting over the universe expanding forever.

Answer 2

How in the world did you get those numbers, and how did a high school calculation give you that 52% number?

Here's the current measurements: 30% of the universe is matter, and 70% of the universe is Dark Energy. That's not 70/30% of the geometrical volume, but of the actual energy content of the universe. Of the 30% of the matter in the universe, only ~5% is "baryonic matter." That's technical term, but for our purposes here it means "normal matter" that interacts with light (like protons, neutrons, electrons). The other 25% has to be sometihng else that doesn't interact with light, hence why we can't see it. Measurements also show that this stuff has to be "cold" - not moving very fast (which would make it hot). So we call it Cold Dark Matter.

Where'd it come from? They derived an equation (I forgot the name) from General Relativity, took some measurements of the expension of the universe (how much mass and energy inside the universe determines how it expands), the density of the matter that we see, and several other factors. Then they fit that data to the equation. To see evidence of the Cold Dark Matter, they model the motion of galaxies and show that something we can't see but has mass must be out there around our galaxies.

Answer 3

I think the whole thing is a bunch of crap. Imagine this, I walk into my lab, do an experiment and my observations do not match my calculations. So to explain this I say it must be because there is a new type of matter that nobody has ever seen. I know what my colleagues would say, either my calculations are wrong or my observations are wrong or both and they would be right.

Answer 4

Do you know how big the universe is? Do you know the exact size of all planets, moons, suns and asteroids are? I didn't think so.