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Missing Matter, Parallel Universes?
Phoghat writes "Could mirror universes or parallel worlds account for dark matter — the 'missing' matter in the Universe? In what seems to be mixing of science and science fiction, a new paper by a team of theoretical physicists hypothesizes the existence of mirror particles as a possible candidate for dark matter. An anomaly observed in the behavior of ordinary particles that appear to oscillate in and out of existence could be from a 'hypothetical parallel world consisting of mirror particles,' says a press release from Springer. 'Each neutron would have the ability to transition into its invisible mirror twin, and back, oscillating from one world to the other.'"
And in this parallel universe, everyone has a goatee.
The missing matter is all in the form of single unmatched socks.
... is the observations that dark matter not only doesn't interrupt with electronic matter (except gravitationally) but also doesn't interact with itself.
Lacking <sarcasm> tags,
Luckily we have more than one cosmologist, so it's not really a problem if some try new explanations (and maybe get to test them), because we have other cosmologists doing other things. Or are you going to suggest that there's only one cosmologist, going backwards and forwards through time and across the whole universe?
I sometimes forget... I'm the evil twin. Gotta go find the "good" version of me and get rid of him.
Home of the Evil Spock.
Yep. And guess where the 'missing matter' went? Beards.
There's no place like
Remember, just because you have an evil twin doesn't mean *you're* not evil too.
Please do not read this sig. Thank you.
You mostly have that backwards. "Normal people" invent outlandish untestable explanations -- often with reference to supernatural intelligences -- for unexplained phenomena all the time, whereas the "mirror particle" hypothesis makes quite specific, testable predictions (and specific tests are recommended in the paper.)
Dismissive assumptions are so much more scientific than actual testing.
We read all this stuff trying to understand anything and all, and then the next paper they release will just say "Bazinga!"
When cosmologists talk about parallel universes, they have a very precise meaning, not Star Trek kinda parallel universes. In this case, a parallel universe is a plane of spacetime that is an actual distance away (through one of the higher dimensions in, for instance, M theory). Some particles that aren't attached firmly to our plane can travel between them (gravity is thought to be weak because of this). So if a cosmologist says that a parallel universe might be the cause of some effect, they *probably* have an idea for a mechanism, not just "They're like us, but they all have goatees!" These ideas are very difficult to test at the moment, so most of the work is theoretical, but they're not unfalsifiable in principle. This is why we do things like build bigger and bigger particle accelerators; it lets us create the conditions needed to test some of these crazier ideas.
I'm guessing the people who thought relativity and quantuam mechanics were bupkis probably used similar lines of reasoning.
You might want to try reading Brian Greene's "The Elegant Universe". It a fairly approachable book on superstring theory and hidden dimensions for laymen.
The theories are very elegant and well thought out but are inherently difficult to prove since the sizes of the things that need to be seen are so small that they are currently unseeable, or energies required are so huge we can't produce them, so there is currently no way to experimentally prove the theories. The main superstring theories suggest 10, 11 or 26 dimensions of which we can actually see only four.
No one is advocating embracing superstring theory, hidden dimensions or multiverses as fact, since even their advocates know they are only theories, but neither should they be discarded as "bupkis" until they are disproved since they may be a way forward in understanding and resolving unresolved conflicts in quantum mechanics in particular. They are regrettably as difficult to disprove as they are to prove.
I'm of the opinion if smart people want to keep thinking about these things they probably should. Just because they are very hard problems doesn't mean they should be given up on. If smart people like the people that wrote this paper can figure out novel ways to test these hard problems, more power to them.
@de_machina
Yes and no. Your link refers to mirror matter based only on parity symmetry while I believe the paper at hand is more general. The arXiv preprint discusses this at the start:
Concerns about parity are irrelevant for our following discussions: they extend to a parallel sector (or sectors) of any chirality. Nevertheless, in the following we shall name the twin particles from the `primed' parallel sector as mirror particles.
To set things up, imagine stepping through a mirror and doing some physics experiments. You would expect everything to work out the same as before so long as "left" and "right" were reversed (...along the axis normal to the mirror...). That turns out not to be the case, which was surprising--some decades ago a few experiments with relatively exotic particles didn't work out as expected (brief history here). Thus matter "through the mirror" and "before the mirror" are distinguishable. It's possible that matter through the mirror exists in our before-the-mirror universe, though it shouldn't interact much with the matter we're used to because the force-carrying particles need to be mirrored as well which ends up leaving only gravitational interactions. As you may have guessed, this is a potential candidate for dark matter. The lack of electromagnetic interactions would prevent distant mirror matter from being seen, and the lack of strong or weak interactions would nix many lab tests (like those that detect neutrinos, which are detected by their weak interactions).
My (poor) understanding of the paper is that they consider an essentially arbitrary parallel universe with wimpy interactions with our own universe (except gravitationally), not necessarily just one created by parity changes. In particular they focus on transitions of neutrons from our universe to the parallel one and use such transitions to explain an anomalous dependence on magnetic field direction in a previous experiment.
As usual, caution is the best plan. The authors call for more experiments, and I'm sure there are numerous explanations for their results that don't require (IMO) spooky transitions between parallel universes.
The only way to transcend between the worlds is a modified transporter beam.
wrong you can also end up in the mirror universe if you have accident while in transit through a stable wormhole.
http://en.memory-alpha.org/wiki/Crossover_(episode)
---Saying gnome 3 is better than windows 8 not so much a compliment as it is damning with light praise.
Is it possible that dark matter, dark energy, black holes and the Oort cloud don't exist at all, but are fanciful constructs that are required to explain certain observations according to currently “accepted” cosmological theories? There is a theory based upon known laws of electricity, that can explain the all observations without resorting to these esoteric constructs, which are nothing more than mathematical fiction. When the accepted picture of the universe put the Earth at the center, it also took fanciful models to account for the limited observations that were possible before telescopes were invented. When increasing technological ability made many observations and measurements of the solar system, the stars and eventually the galaxies, it was finally necessary to discard the old earth centric cosmology. In the same way, modern instruments have brought back a lot of results that are “puzzling” the scientists adhering to the present accepted view of the gravitational universe model. Interpreting these results by postulating that electricity and magnetism are the dominant forces, rather than gravity, the picture of the universe becomes much more coherent. Far out stuff like parallel universes and other exotic explanations are no longer necessary, but many PhD theses and science funding will have to be re-done. A fundamental paradigm shift of our view of the universe is necessary.
A sufficiently advanced simulation is indistinguishable from reality.
There were many scientists in earlier times when most people still believed in God, who did groundbreaking work in science and mathematics. There are names like Nicholas Copernicus, Sir Francis Bacon, Johannes Kepler, Galileo Galilei, René Descartes, Blaise Pascal, Isaac Newton, Robert Boyle, Michael Faraday, Gregory Mendel, William Thomson Kelvin, Max Planck and Albert Einstein. There are others that could be added to this list. It is quite clear from history, that belief in a Creator God does not preclude great scientific discovery and mathematics.
A sufficiently advanced simulation is indistinguishable from reality.
As I recall general relativity took four years to confirm experimentally from the time it was published in 1915 until observations of a full eclipse established that space did bend around the Sun. Some of the teams involved had flawed experiments which seemed to disprove it, and Einsteins hopes for a Nobel Prize were frequenty dashed when, for example, an attempt to observe an eclipse during World War I ended when the German team was arrested in Russia for espionage.
One wonders how long it would have taken to prove general relativity if we didn't happen to have a moon just the right size to create a full eclipse of the Sun.
It wasn't until 1959 that better tests, using radio frequencies, were designed that better proved the predictions of the theory.
In the case of Superstring theory they have run in to an even tougher challenge since the things that need to be observed are the size of the Planck length so they are impossible to observer with current technology.
In quantum mechanics there is still a dispute over a possible hidden mechanism behind quantum entanglement and "spooky action at a distance"
@de_machina
Baryonic matter ("normal" matter from our perspective) is the minority.
WE are the Goatse Universe.
NOOOOOOOoooo ... oh, wait, that's not what you said. Phew.
"What in the name of Fats Waller is that?"
"A four-foot prune."
Just a minor note: Einstein won his Nobel for his work on the photoelectric effect (which ironically helped launch the quantum theory he distrusted the rest of his life), not for relativity. I'm not sure if you meant to imply that or not.
So, limiting the discussion to dark matter and dark energy, which are still open to debate, it would be nice to have a score card of what is in and out.
WIMPs are out.
Mirror matter in and out, apparently.
String theory, in then out then in but not nearly as cool as it was the first time.
My theory is that fundamentally the big bang theory is mis-understood. The universe, as we know it, is currently under construction and subject to change. Not on human time scales, but if we wind back the clock and play it forward, the universe has been getting weirder. Look at the growth of the periodic table since the beginning of the Universe, the birth of protostars and galaxies, etc. I don't see why it isn't capable of continuing to increase in weirdness.
This begs the question of how is the Universe getting weirder. This is where the big bang theory draws dragons and warns of impending doom. I like to think of it as if two water droplets were coming together. One is red, one is blue. When they mix, they create a Purple center. Our Universe is the purple part. From inside the purple part, you can't see the red and blue Universes and it would appear, if you wound back the clock, as if the Purple Universe appeared out of nowhere and it would also appear as if the Purple Universe was not only growing, but the growth would be accelerating. This doesn't break the big bang theory and doesn't break any other known theories. It does remove the need to explain expansion and other observations.
Is that any stranger than mirror matter or string theory?
I don't see what hair styles have to do with anything...
oh really?
explains a lot, actually.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
Your score card is hosed:
WIMPs are hypothetical, and neither in nor out.
Mirror matter is hypothetical, and neither in nor out.
String theory is untestable, and is a hypothesis, not a theory.
As for your theory, it's not even a theory - it's an idea, and probably hasn't even reached the hypothesis stage, much less the theory stage. A theory has to be testably disprovable: for a hypothesis to become a theory, you have to define observations or tests capable of disproving it. (Note that a theory has to be disprovable, not provable. This is intentional.)
As for your idea, you're looking at the universe as a big, macro-sized 'thing' that is capable of being under construction and subject to change. You consider the universe capable of "getting weirder" as though "weird" were some bulk property, like water being "wet".
The fact of the matter is that the universe is composed of many, many, many small particles, that all obey very simple rules, and that pretty much everything we've ever observed is explained by those very simple rules. There is no global 'weird' which has been increasing - the last 13 billion years are perfectly well explained by these same simple rules.
There are places where we know those rules work differently than we expect - but that in no way invalidates the places where we do know how they work.
-dentin
Alter Aeon Multiclass MUD - http://www.alteraeon.com
And the even more evil Kira Narise and her goateed buddy Ben.
Free Martian Whores!
Please, repeating it is electricity, not gravity molding the Universe doesn't make it so. Cosmology's assumption that it is gravity* holding everything up is due to observation, not bias. Also, you just go to show that you have no idea how electricity behaves.
* Well, gravity, except for dark matter that may not be so (but probably is), and dark energy that definitively isn't so. But the fact that those are not gravity doesn't mean they are electricity.
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