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New Hubble Release Puts Another Nail In the Coffin of Dark Matter's Competitors (spacetelescope.org)
StartsWithABang writes: When it comes to the structure of the Universe — forming the galaxies, clusters, and Universe as we see it — the normal matter we know of simply isn't enough. Given our best-understood laws of physics, including Einstein's general relativity, what we see of galaxies and the Universe in general simply doesn't match up to our predictions. The simplest solution, arguably, is to just add a new ingredient: a new form of matter, a dark matter if you will. But a counterargument is that we've got the laws of gravity wrong, and that no new matter is necessary. There's only one way to settle an argument like this: with data, evidence and the full suite of observations at our disposal. The newest Hubble release, along with four other independent lines of evidence, rule out modifications of gravity and leave dark matter as the only option standing.
None of the references point to co-gravition, or Heaviside's force, which seems to produce much of the desired results called for. Co-gravitation just requires to rethink the nature of energy, though, since it implies that the gravitational field is a sink of energy, Flag as Inappropriate. A good deal of work has been done by the likes of O. Jeffimenko, and more recently T de Mees. Heaviside suggested the necessary forces in 1893.
OS/2 - because choice is a terrible thing to waste.
Thank you. I just can't bring myself to accept dark matter as a viable option. It seems so ad hoc. It is only the best explanation given our current knowledge.
While I agree with you, I am forced to contemplate some of the speculations about how wormholes (if they do indeed exist) and warp drives created without massive singularities as drive components (Read: Impractical) could be constructed and the only working models that have not been ruled as impossible involve some magical stuff referred to as "Exotic matter" of which this dark matter is a proposed type. (This is Non-Baryonic matter I am referring to.) This means that there is more to matter than the standard model predicts and that things like FTL via space warping by some sort of practical means, or the means to travel via wormholes (which includes time travel) and anti-gravity, is still not ruled out.
There is good and bad and intermixed between the two is confounding and confusing until we have the right set of epiphanies.
That actually makes some intuitive sense. My only problem with "dark matter" is the term itself: I saw recently in Nature (the science mag) that one astronomer had proposed the term "transparent matter," which I like a lot better.
Development is programmable; Discovery is not programmable. (Fuller)
The problem physics faces is that it is using mathematical methods which assume physically implausible foundations. It is then faced with the problem of incomplete knowledge. I shall illustrate the issues using metaphors that anybody with half an ounce of computer science common sense should get. (For reference, my area of doctoral studies was models of PA, in the region of mathematics which gave birth to modern computing.)
Consider modern hashing. If I know the correct input, I get the correct output. If I am off by one bit, but do not know which bit, and the input is 128bits, I have a 1/128 chance of getting the correct output. If I am off by two bits, I have a (1 / 128 choose 2) chance, and as the number of bit errors increases, this probability gets close to zero. Quantum mechanical effects occur when the number of bits of entropy get small, so that this probability becomes experimentally distinguishable from zero. Something like that.
Now consider that energy and mass are equivalent via Einstein's famous equation. Neglect the complex stuff for now. The current theoretical best idea is matter being vibrations in strings. For now I will just take a conceptually simple version to illustrate. A short vibration in a long string takes time to travel, and if this speed is c (lightspeed) and the string is long and coiled, it will take time to get to a place where one particular observer can see it. Likewise photons have to reach us before they can register. Of course interactions between matter through the elecromagnetic field happens via photos.
The obvious explanation is that there is some hidden delay in the underlying physics so that only, say, 5% of the energy in the universe is visible to an observer at any time. What this '5%' actually is will follow from the underlying structure, but quite possibly this cannot be probed by conventional experimental means since it is necessary that the part of the universe experimented on needs to be held constant, thus precluding conventional experiments using physical objects. Again, this is a sketch idea to be pondered, not a claimed 'final theory'.
The thing is, if energy is invisible due to delay, but still contributes to the overall mass inside our universe, these 'dark energy' type sum mismatches might be the only evidence they are there at all. But getting this right means getting the mathematical framework right, and mainstream theoretical physicists are still mostly using stuff done with methods that were beginning to become unstuck in the late 19th century. Issues with calculus gave rise to analysis using limits, and these were founded on arithmetic and set theory. But these last two assumed an infinitude of distinct objects with which to perform computations. It is known now that this is physically implausible. Thus one needs to use more strictly bounded arithmetics and recursive constructions using precisely accounted computational resources to form foundational models which can correspond to physically plausible structures. By studying such structures and limiting towards the ultimate capacity of the physical universe (think Bekenstein bound here) we will be better placed to sort out this theoretical mess. Current mathematical methods are simply not up to the task.
(google "John Allsup Mathematical Genealogy" and see where I fit in the Ph.D. tree to get an idea of the area I was trained in: life circumstances rendered a conventional career infeasible, which is why I have no academic reputation, but I have kept an eye on progress, and have kept my logical reasoning skills sharp, just in case.)
John_Chalisque
So was the hypothesis of the neutrino before it was actually detected. You see, there was this anomaly in the beta decay spectrum and it was hypothesized that the missing energy was carried away by this particle called a neutrino. Decades later the neutrino was actually detected. In what way is dark matter different?
The neutrino hypothesis included some very specific property values for the particle, and possible ways it could be detected. Dark matter, not so much.
"Somebody has to do something. It's just incredibly pathetic it has to be us."
--- Jerry Garcia
No it is not. The neutrino was ONE possible explanation that turned out to be the correct one. A quite famous physicist called Niels Bohr had a different solution to the problem. So not at all different from today, where different people have different ideas how to solve this problem. The scientific way is to follow through and investigate ALL of them.
It's only handwavy because you don't want to take the time to understand the evidence for it and against it. There is a lot of evidence for the WIMP model of dark matter, including the current data just posted and things like the Bullet Cluster.
As we stand in the middle of a conversation about matter we've conveniently labeled as dark**
Here, I'll illustrate your wrongness with an analogy which should make sense to you.
You're standing in a dark room with one other person. You know he's there because you can feel his dick in your ass. Suddenly, you get hit in the face, which doesn't make sense because you know for certain that the only other person is standing behind you, furiously stretching your anus. You may decide this indicates the presence of another, previously unknown, black man in front of you. Or you might come up with an idea that a being of pure homosexual energy from another dimension opened a portal in front of you, and slapped you in the face with it's fist-shaped cock. Now as much as you personally desire the second idea to be true, it is far more likely and in line with known evidence for the first one to be true... even if in you later discover the person is a Cracker or a Slope instead of a Darkie that hypothesis is still far more correct than the one you're proposing.
Realistically, wormholes or not, even a civilization limited to light speed travel should have been able to colonize or visit most of the galaxy in just a few million years with robotic exploration. So, it is looking like there is either no one else out there, or just as likely, there is some sort of barrier to intelligent civilizations being able to launch such an effort like colonization or robotic exploration.
Obviously, this all assumes that someone would have done all of this first. We might be either the first civilization at this point, or at the very least, a member of the "first wave" of civilizations where the other civilizations do exist, but their evidence has not yet arrived here. That scenario is just as likely as any other solution, but it is less useful because then we have nothing yet to look for in order to confirm our theory, so we tend to assume that we're not a member of "the First Ones".
There is also the idea that there may be a "Great Filter", which is some sort of event or situation that all intelligent species run into before they can do interstellar exploration. It could be something like nuclear holocaust or self-destruction being inevitable, or as simple as running out of available energy to be able to maintain high technology before they could start the program. Or some combination.
Nuclear war, unfortunately, is probably inevitable. It is a more distant threat than it used to be, but the weapons are all still there, and even pariah states like North Korea have working weapons. While those states remain somewhat rational, we're probably fine, but the stakes are pretty high.
Another possibility is simple overheating. Here I'm not exactly talking about Global Warming as caused by carbon emissions, but actual generation of heat by releasing it through energy production as waste heat. Solar energy doesn't help us with this because increased capture of solar radiation will increase waste heat on Earth. Eventually, carbon dioxide or not, we might simply add more waste heat to the planet than the Earth can actually radiate out into space. In that sense, I am very much a believer in AGW, although that scenario is probably more remote in time than a CO2 based greenhouse effect. Eventually, the Earth will need a giant heat sink if we want modern civilization for ever increasing numbers of people.