Maybe its a weak force like gravity that is weaker and only shows its effects in cumulative forms. Maybe it compresses galaxies into the cosmic strands at the same time it drives the expansion of the universe.
Posted on 03/12/2015 10:32:02 AM PDT by BenLurkin
Now, you might be saying, if we don’t know what this thing 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?
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 galaxy clusters, but the modern calculations were made by Vera Rubin in the 1960s and 70s. She calculated that galaxies were spinning more quickly than they should.
... 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.
And here’s the amazing part. Astronomers can then map out regions of dark matter in the sky just by looking at 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.
(Excerpt) Read more at universetoday.com ...
The Democrat Party is the physical manifestation of Dark Matter.
Then all you have to do to win a Nobel Prize is prove their equations wrong.
Dark matter is a theory that explains observations. It could well be wrong, but right now it's what best fits what can be seen and measured. That's how science works. A thousand years ago, science said the heavens were crystal spheres.
I’m impressed. Thank you.
The vicosity of the “uncompressable” medium aspect of the space time metric may also account for the reason we also have a speed of light.
That's the trouble I've always had with the 2-D model.
You really have to mentally visualize it in 3-D to see what's really going on.
I visualize it as a central point of gravity (mass) influencing a sphere of space surrounding it.
The 2-D visualization, always presented, is somewhat misleading.
They didn't forget, they decided to ignore it as inconvenient. Because you cannot use a two dimensional model to demonstrate the behavior of three dimensional objects in a three dimensional universe.
And let's not get into the ~12 dimensions of M theory.
Excellent piece. Thanks for posting this on FR.
Dark matter may exist.
Or it may be this century’s Ether.
And they don't conform because our knowledge of the forces of nature is extraordinarily limited. We don't know nearly as much as scientists say we do.
Well, "fudge" *is* typically dark matter ....
This century’s ether is the zero point field.
The strong force is an infinite point of finite gravity which neutrons and positrons are drawn into orbit around.
The higher energy electrons exist outside the nucleus.
All dark matter is made up of matter traveling faster than the speed of light.
I don’t know anything about dark matter... But I know there’s a black hole in the white house....
That’s not really true. Scientists have actually considered that our current understanding of gravity is faulty. It’s done via a model known as MOND, which stands for Modified Newtonian Dynamics. MOND works pretty well for explaining the rotation curves of galaxies. In fact is does so a bit better than dark matter does. However, nobody has worked out a MOND model that works even approximately for a whole host of other observations that dark matter accounts for quite well. Some of these are fairly complex and esoteric, but one example is that dark matter can account for the observed irregularities in the cosmic microwave background, whereas all the MOND models fail disastrously at predicting what these irregularities should look like. Another fairly easily understood example is that dark matter theories can account for the initial isotope ratios in the universe whereas MOND models cannot.
That is why current scientific understanding is that MOND is not the preferred model and that dark matter is. It’s not that scientists refused to consider that the current understanding of gravity is incorrect. Rather, it is that they did consider that possibility, but even modifying our models of gravity does not account for the observations.
Thank you. Very well put. It’s easy to criticize scientific models, much more difficult to come up with the evidence to show that they are wrong and develop a replacement model.
We know that light is distorted by knowing the astrophysics of the source of the light. Stars have spectra that appear a certain way. Supernova spectra are also known. Ditto spectra of cephid variables, neutron stars, gamma ray bursts, and a whole host of other astronomical objects. When we see distortions in the light from these objects, we know because we know the process by which that light was produced.
Don’t get me wrong: dark matter may well turn out to be wrong. It’s not enough, though to just say it is. You have to provide evidence that it is. That evidence, right now, would best be delivered in the form of a coherent alternative model that explains known observations. Dark matter, whether you believe in it or not, does explain a fairly wide range of astrophysical and cosmological observations. A better model might well explain those observations, and others, better. It’s not as though scientists haven’t considered alternatives. Many on this thread believe that modified gravitational theories are the answer. However, these have been studied pretty extensively (look up the acronym MOND, which stands for modified Newtonian dynamics if you are really interested). Right now, dark matter is the best model we have.
Your cartoons are very misleading. All four forces are very well understood and very well mathematically modeled.
First of all, in a very real sense, there are only three fundamental forces. The weak and electromagnetic forces are really different aspects of a single electroweak force, in much the same way that electricity and magnetism are not separate forces, but rather dual aspects of a single phenomenon. The difference is that under conditions that are present right now, we cannot directly observe the connection between the electromagnetic and weak forces in the same manner that we can observe the connection between the magnetic and electrical forces. Nonetheless, a mathematical model of both is on very firm footing. No deviations from the predictions of this model have ever been observed. BTW, the 2nd cartoon panel is misleading here. Is the electromagnetic force governed by an inverse square law or by Maxwell’s equations? The answer is yes. Maxwell’s equations are actually the more general form; they imply the inverse square law that is depicted there.
The strong force is also very well modeled by the theory of quantum chromodynamics. Just like with the electroweak theory, there has never been an observation that counters the theory of quantum chromodynamics. The source of the strong force is well known. It arises from interaction of quarks, which are the fundamental particles that comprise protons, neutrons, and other non-elementary subatomic particles.
Finally there is gravity. Again, your first panel is misleading here. Gravity is NOT governed by the inverse square law posted there. That is Newtonian gravity, and it is only an approximation. The true equation, which encompasses the Newtonian approximation under many conditions, is the Einstein field equation of General Relativity. By now, you probably are seeing a theme. No observations that contradict General Relativity have ever been made.
We do indeed understand the forces of nature quite well. You may wonder, then, if we haven’t yet encountered any observations that counter the prevailing models of these forces why we need to investigate things like string theory. The reason is that the history of physics has been that seemingly unrelated phenomena have been found to be unified under increasingly larger frameworks. For instance, it was generally believed that the laws governing bodies in the heavens were different from the ones governing bodies on earth. Physics unified the heavens and the earth under one framework of laws. This was really Newton’s great achievement. As mentioned above, early investigators did not realize that electricity and magnetism were related. They were unified under a larger framework, one which rather shockingly also was able to encompass light as well. Therefore, we are led to ask the question, why are there four forces (or more technically three) instead of just one? Can we unify these forces? That’s where theories like string theory come into play.
Besides the drive for unification, the other reason that new theories like string theory and quantum gravity theories are being investigated is that while all three force theories are very well verified within their domains, when we get into domains where more than one might apply, we get contradictions. Most notably, general relativity and quantum mechanics (which includes both the electroweak and QCD theories) conflict with each other. That indicates that there’s a deeper level of physics to uncover, but it does not indicate that we don’t have an understanding of these forces, just that we don’t know the entire picture.
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