The end to a mystery?

Jan 31, 2008
The end to a mystery?

Astronomers at the University of St Andrews believe they can “simplify the dark side of the universe” by shedding new light on two of its mysterious constituents.

Dr HongSheng Zhao, of the University’s School of Physics and Astronomy, has shown that the puzzling dark matter and its counterpart dark energy may be more closely linked than was previously thought.

Only 4% of the universe is made of known material - the other 96% is traditionally labelled into two sectors, dark matter and dark energy.

A British astrophysicist and Advanced Fellow of the UK's Science and Technology Facilities Council, Dr Zhao points out, “Both dark matter and dark energy could be two faces of the same coin.

“As astronomers gain understanding of the subtle effects of dark energy in galaxies in the future, we will solve the mystery of astronomical dark matter at the same time. “

Astronomers believe that both the universe and galaxies are held together by the gravitational attraction of a huge amount of unseen material, first noted by the Swiss astronomer Fritz Zwicky in 1933, and now commonly referred to as dark matter.

Dr Zhao reports that, "Dark energy has already revealed its presence by masking as dark matter 60 years ago if we accept that dark matter and dark energy are linked phenomena that share a common origin.”

In Dr Zhao’s model, dark energy and dark matter are simply different manifestations of the same thing, which he has considered as a ‘dark fluid’. On the scale of galaxies, this dark fluid behaves like matter and on the scale of the Universe overall as dark energy, driving the expansion of the Universe. Importantly, his model, unlike some similar work, is detailed enough to produce the same 3:1 ratio of dark energy to dark matter as is predicted by cosmologists.

Efforts are currently underway to hunt for very massive dark-matter particles with a variety of experiments. The Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) in Geneva is a particle accelerator that amongst other objectives, could potentially detect dark matter particles.

According to Dr Zhao, these efforts could turn out to be fruitless. He said, "In this simpler picture of universe, the dark matter would be at a surprisingly low energy scale, too low to be probed by upcoming Large Hadron Collider.

“The search for dark-matter particles so far has concentrated on highly-energetic particles. If dark matter however is a twin phenomenon of dark energy, it will not show up at instruments like the LHC, but has been seen over and over again in galaxies by astronomers."

However, the Universe might be absent of dark-matter particles at all. The findings of Dr Zhao are also compatible with an interpretation of the dark component as a modification of the law of gravity rather than particles or energy.

Dr Zhao concluded. “No matter what dark matter and dark energy are, these two phenomena are likely not independent of each other.”

Dr Zhao and his collaborators' findings have recently been published by Astrophysical Journal Letters in December 2007, and Physics Review D. 2007.

Theories of the physics of gravity were first developed by Isaac Newton in 1687 and refined by Albert Einstein's theory of General Relativity in 1905 which stated that the speed of gravity is equal to the speed of light.

However, Einstein was never fully decided on whether his equation should add an omnipresent constant source, now called dark energy in general.

Astronomers following Fred Zwicky have also speculated additional sources to Einstein's equation in the form of non-light emitting material, called dark matter in general.

Apart from very light neutrinos neither dark sources have been confirmed experimentally.

Source: Science and Technology Facilities Council

Explore further: The unifying framework of symmetry reveals properties of a broad range of physical systems

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User comments : 11

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Ragtime
1 / 5 (2) Jan 31, 2008
With full respect to Chinese experts, the main difference between dark matter is in the sign of action. While the dark matter attracts the common matter and it's being attracted by it the dark energy is supposed to increase the expansion of Universe, i.e. it repels the common matter.
ezezz
4.2 / 5 (5) Jan 31, 2008
I'm sure these astrologists are aware of that. Still it seems intuitive that they should be related, even without having a mathematical model linking them at hand. Until dark matter and energy were conceived gravity was a pure force having no variation. What are the chances that two unseen but apparently pervasive and powerful forces in some sense superseding the common workings of gravity are unrelated?
LearmSceince
3 / 5 (2) Jan 31, 2008
Yes, they both have "dark" in the name, so they MUST be related!
k_m
4.5 / 5 (2) Jan 31, 2008
If dark matter were attractive to normal matter yet repulsive to itself, is it not possible that dark matter is expanding the universe and carrying normal matter with it?
Thinking of it that way... doesn't it seem plausible that dark matter is the fabric of space?
mgmirkin
3.7 / 5 (3) Jan 31, 2008
Both Dark Matter and Dark Energy are kludges invented to save the gravity-only paradigm cosmologists currently favor, but which is incapable of accounting for so many things in the universe.

We need to go back to the basics and re-examine key experiments with much newer / better equipment than was available 100-200 years ago when some of the first tenets were laid down (before the advent of nuclear and plasma physics, before electricity was widely understood).

Just my opinion, of course.
deatopmg
1 / 5 (3) Feb 03, 2008
By measurement it is clear that gravity is MANY orders of magnitude faster than light. WHat does that do to GR/SR? like any religion the establishment just ignores the experimental data or ostracizes the heretics. AE pondered this until his death.
LearmSceince
5 / 5 (2) Feb 11, 2008
mgmirkin: Updated measurements have been done concerning basic principles of SR.

deatopmg: Totally incorrect. No measurement has been made for the "speed of gravity", and indirect evidence agrees with GR that it propagate at the speed of light. Experimental evidence is not ignored, but constantly improved upon and retested. See http://math.ucr.e...nts.html for details.
superhuman
5 / 5 (1) Feb 24, 2008
Yeah it would be much more surprising to me too if it turned out that they are NOT 2 different manifestations of the same thing.
darkmatters
5 / 5 (1) Mar 27, 2009
The effects of dark matter are what constitutes the idea that its even there.though some scientists believe it is a transparent plama,which like almost anything else that is transparent,bends light.They will be testing this theory soon,but until all of these tests are completed and all of the optical provisions are put up,i like the idea of it being a WIMP.
japeney_jolly
1.5 / 5 (2) Apr 02, 2009
I think dark matter is a silly idea. I don't think its good science to just invent universes of extra matter without any observational evidence just because it would make our models work. Its more likely that we just need to reformulate our models. there are many other models that can account for the effects that dark matter is invoked to explain. One is that gravity actually weakens with an extra exponential term till it becomes proportional to the inverse of the distance rather than the inverse of the distance squared. Another is that there is a sort of environmental pressure intrinsic to space that exerts force on all objects - and that objects, like planets, that interfere with this pressure create an area of low pressure in between the planet and whatever object you are measuring the attraction with. At large enough distances, this type of model exhibits the correct sort of gravitational behavior also. There are likely many ways to explain what is happening. You just have to know that every scientific model we have is just an analogy that happens to enable us to make accurate predictions. Its not actually "truth." Scientists are dogmatized by the great scientific theories of the past and start to see them as truth, but in reality they are just really effective mathematical analogies. The idea of dark matter is popular because agreeing with does it two things:1. it allows scientists to not have to violate their faith in principles that they have taken for "truth." 2. adds to the never-ending mystery of the universe, i.e. gives scientists a much bigger universer to play around/discover within! I asked a professor of mine (a string theorist) what he was looking for, and when he would be satisfied in his search for knowledge. He said he would never be satisfied no matter what he discovered! Never satisfied! He doesn't WANT the search for truth to end, its like an addiction to him, and I'm sure its that way to many scientists. Either way, I think the dark matter thing is just as bunk as the lumineferous aether. Its just a fashionable opinion. In MY opinion, there are a great many theories that could be developed just as well, and we could easily start from scratch with totally different assumptions and come up with a completely different explanatory framework just as viable as the physics we have now. Oh well, if they find a mathematics that works, I suppose its as good as any other!
jonnyboy
1 / 5 (1) Apr 02, 2009
japeny_jolly,

All I can say is WOW, you figured it out, it's the boogeyman that did it!!!!!!!!