Posted on 07/27/2018 3:36:24 PM PDT by LibWhacker
Ever since the late 1960s when Vera Rubin and Kent Ford discovered that galaxies don't behave the way they should, scientists have been looking for the mysterious substance behind that behavior. That theoretical stuff is called dark matter, and while it's invisible to telescopes, it has mass, which means it can show its might through the force of gravity. Of course, that's all theoretical. Some might even say it's a little too convenient, as if scientists just came up with a magical substance that makes the math work. What makes us so sure that dark matter is even a thing?
Hold Me Closer, Tiny Particle
"People ask this question a lot," said Katie Mack, a theoretical astrophysicist at North Carolina State University who studies dark matter. "You know, maybe dark matter is just a fudge factor or something." But for astrophysicists, dark matter is much more than that.
If you go back to high school physics class, you may remember that the more mass something has, the greater its gravitational pull. If galaxies were only made up of the stuff we can see, there wouldn't be enough gravity to keep them together, much less to keep the stars in the sparse outer edges orbiting just as fast as those in the center. In fact, scientists reckon that normal matter makes up less than five percent of the universe. Dark matter seems to make up a whopping 27 percent. (The rest is a mysterious force called dark energy.)
You can also see its mass in the warping of spacetime itself. According to Einstein's theory of general relativity, matter curves the fabric of spacetime the way a bowling ball curves the fabric of a trampoline. When light travels toward that curve, it doesn't go in a straight line. Instead, it follows the curve, bending around the massive object before continuing on its path. That warp in spacetime turns into a sort of cosmic magnifying glass in a phenomenon known as gravitational lensing. But yet again, the gravitational lensing produced by a galaxy or a galaxy cluster is too great to be explained by the matter we can see. This effect is yet another piece of evidence for the existence of dark matter.
You can even see unexpected patterns in the cosmic microwave background, the light left over from the birth of our universe, that point to the existence of dark matter. "We see patterns in that that show there had to have been something at early times that brought matter together in a way that can't work with just regular matter," Mack told Curiosity.
All Signs Point to Yes
It's not as if scientists have never tried to find an alternative. Instead of dark matter, maybe gravity just doesn't behave the same way everywhere in the universe. Researchers have tried tweaking gravity to make galaxies rotate differently than Einstein's theories say they should, sans dark matter, and it can work but then other observations we've made don't match up. In the end, Mack says dark matter is the most likely explanation we've got. "I'm not sure what it is that makes it more appealing to break general relativity and say that all these huge observations are wrong, versus 'there's a particle we can't see."
"It's kind of like if you were walking down the street and you see a plastic bag sort of move across the street in front of you," she said. "And then you see some trees lean over, and then you hear this kind of rustling sound, and then you feel a little bit of cold coming from one direction, and then you see a street sign swing, and you're like 'That's wind!' You can't see the wind, but there are all of these different pieces of evidence that air is moving.
"It's kind of the same with dark matter. We can't see it directly, but there are so many pieces of evidence that it just makes more sense than any other explanation that we can come up with."
dark mater is the failure of a mathematical equation that theoretical physics use to prove mathematically they can figure the rules governing the universe.
Basically the math does not ad up unless the Mathematicians substitute some numbers that says there is more mass to the universe then is predicted in another mathematical model so this mas is called dark mater because we currently cant detect it .
For me it is quite comforting that we don’t have everything figured out... who wants to live in a world with out mystery and wonder... Who wants to live in a world where all is explained.
congress
Most of the mass is the result of an interaction and not of the particles themselves. Hence the term “dark matter”. It is misleading as it is not matter at all but a way of quantifying how matter interacts in the universe and so far it has not been detected
I agree with you 100% and you said it better than I.
Which equation?
John Fowles: "Mankind needs the existence of mysteries. Not their solution."
Maybe the theories and equations are wrong, and theres no dark matter.
WE KNOW IT EXISTS BECAUSE WE FUND IT!
Very interesting post. To me, it’s all even more unexplained. The idea that there isn’t enough visible matter in the universe to explain what we observe is based upon the assumption that those very fundamental principles that we observe and believe (e.g. that mass attracts mass, like charges repel, opposite charges attract, etc.) are operative everywhere. Are they? We don’t even understand how or why mass attracts mass. We developed atomic weapons based upon release of ‘strong forces’ that we know exist, but the nature of which we don’t understand. We are, at this point in human history, only a few steps into a billion mile journey trying to learn how God works.
John Fowles: “Mankind needs the existence of mysteries. Not their solution.”
That quote, IMHO, is Profound.
I have long considered the implications on a society in which all that can be known was known.
It would be the End. Like driving a bus with all of mankind on board at 1000 mph for centuries and hitting a brick wall.
Everything thing stops. The future stops. Hope Stops. All that continues is the slow motion deconstruction of the billions of pieces of accumulated knowledge diffused into meaninglessness.
Can't argue with that. As to the laws of the universe being the same everywhere, check this out. It's going to blow me away if someday they show that the laws of nature on the far side of the universe are different than here on earth. The universe is strange, but so far it doesn't appear to be that strange!
Not saying this applies to you, USA, but what gets me is that people seem too willing to believe something for which there is little evidence (math and physics is all wrong!), and disbelieve something for which there is a lot of evidence (dark matter exists).
Answer. We donk know that dark matter or energy exist. Our formulae dont work for all things.that doesnt give anyone the right to say something exists. P.S....that sounds like the “god of the gaps”....or in this case...”the maybe of the gaps”
.make new discoveries....stop trying to calculate reality with so few facts....like a blind man doing brain surgery..
The physical constants might vary over distance, but even more bizarrely, they may vary over time.
Dark matter is not DARK matter.
It is the same matter that we see and touch and measure and smell and hear.
However, there is DARK matter as it exists in a different time plane, and that time plane is in the past, where all matter that ever existed (which still exists today), exists in the past, and it’s the matter of the past that is “interacting” with the present, and which scientists still have no way of measuring, and may never be able to do, since, that matter exists in all instances of the past. With more passage of time, the influence of dark matter will increase, and matter that we see in the current instance of time, will become and even smaller slice of the “space/time/matter/energy” continuum.
So, there is your answer. Simple, but complicated.
BTW, there is but one universe, and it’s comprised of matter and energy, which exist in the present and in the past. It’s the past that is being pesky with our cosmologists, and humans in general.
basically I am saying that a lot of times scientists make up the numbers so that they can further there work on a theory when dealing with mathematical models it is valid for there research but drawing any sort of conclusions for the public is insanity.
a good example of this insanity is the cult of global warming the same equations that says man has a noticeable effect on global climate change rather then it being the gravitational effect on volcanoes and the Magnetosphere caused by sunspot cycles and solar flare from the sun is created by made up numbers in a mathematical model.
I love science but unfortunately lot of scientists are intellectually dishonest when it comes to the validity of there conclusions and the media eats up everything not understanding that what is being presented is just a dam good attempt to explain things and a lot of times is just used to reinforce preconceived belief systems
or to make a name for someone presenting am idea that needs more work before it should be looked at as a fact.
Did they go there and set up instruments to measure gravity and orbiting stars?
Or did they stay on earth and "reckon" all their estimates?
I think you are correct. A world without mysteries would die.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.