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All Disk Galaxies Rotate Once Every Billion Years (astronomy.com)
According to a new study published in The Monthly Notices of the Royal Astronomical Society, astronomers discovered that all disk galaxies rotate about once every billion years, no matter their size or mass. Astronomy Magazine reports: To carry out the study, the researchers measured the radial velocities of neutral hydrogen in the outer disks of a plethora of galaxies -- ranging from small dwarf irregulars to massive spirals. These galaxies differed in both size and rotational velocity by up to a factor of 30. With these radial velocity measurements, the researchers were able to calculate the rotational period of their sample galaxies, which led them to conclude that the outer rims of all disk galaxies take roughly a billion years to complete one rotation. However, the researchers note that further research is required to confirm the clock-like spin rate is a universal trait of disk galaxies and not just a result of selection bias. Based on theoretical models, the researchers also expected to find only sparse populations of young stars and interstellar gas on the outskirts of these galaxies. But instead, they discovered a significant population of much older stars mingling with the young stars and gas.
That's interesting.
OK, but why? It seems counter-intuitive that dense galaxies and sparse galaxies, big galaxies and small galaxies, would all rotate at roughly the same speed. The astronomy.com article is light on details and the Royal Astronomical Society's abstract is somewhat incomprehensible to a layman like myself.
Can someone explain?
TFS oversimplifies things a bit. The finding is that the outer edge of these galaxies rotates at about the same rate for all of them. That's not entirely surprising: the more massive the galaxy, the faster the rotation at any given distance, but also the more distant the outer rim. It also implies a similar ration of dark matter to familiar matter across these galaxies - which again isn't shocking, but is interesting if the ration has to be very similar. If it's confirmed they really do line up this closely that's probably big news for those modelling galaxy formation.
Socialism: a lie told by totalitarians and believed by fools.
Okay, so the larger the galaxy, the faster it must spin to complete a rotation in the same time as a smaller galaxy. The more mass a galaxy has means more for dark matter to gravitationally interact with it.. could it be repelling it somehow in order to accelerate it? Or attracting it?
Look back up at my post, now look back down, you're on the Internet. Now look back up. I'm a signature.
Your speculation fails the sniff test.
The electromagnetic force affects a very, very short distance.
If galaxies are "communicating," with each other and are similar to synchronized swimmers, it's going to be via gravity (including the little-understood dark matter) or perhaps entanglement on a quantum level.
There's a lot we don't know, and the substance of this article is on that list.
This is a preliminary finding and serves as a clue, only.
This recent revelation, if verified, could lead us to a solution for the asymmetry between matter and anti-matter.
It little behooves the best of us to comment on the rest of us.
You're applying the wrong toolbox - electrostatics. The macroscopic behavior of charged particles is defined by the domain of plasma physics, not electrostatics. You can observe this simple fact by observing any novelty plasma globe: Plasmas form into filaments within the laboratory, and these filaments conduct electric currents. The filaments tend to wrap around one another without combining, demonstrating both a long-range attraction and a short-range repulsion. What this means, in practice, is that the electric force can be extended to any distance. Wherever the plasma filament goes, it carries with it the electric force.
"Several researchers have reported direct evidence for large scale electric currents along astrophysical jets," and not only that, but in plasma physics, it's not always the case that the plasma emits any light. Plasmas can conduct even while they are in a dark mode - much like the wires in your home, of course.
Let me give you another example of a vindication which everybody missed for electricity in space doing things of importance:
In July of 2016, it was admitted that many galaxies exhibit two separate bulges:
People who do not track the electricity in space debate would not see this as a vindication for those claims, but it certainly is.
Anthony Peratt simulated proper galactic rotation curves in the early 80's on government supercomputers without the need for any dark matter. . Look carefully at the simulation results, and you will see your two separate bulges.
Slashdot is mangling my links. Here's the link to Peratt's galaxy simulation: plasma-universe.com/Galaxy_formation
i mean really,
#define kGALAXY_ROT_SPD 1000000000
?
I think it is far more likely we are running into relativistic situation. The outer rim will rotate the fastest but it can only approach the speed of light, so time needs to start slowing down. Perhaps on a large enough scale, we hit the magic point that the article speaks of
"When life gives you lemons, don't make lemonade. Make life take the lemons back!" -- Cave Johnson
Well, I am sure you can find a spot or a metric where the numbers fit, like the researchers here did, but galaxies are not rigid and thus does not have a constant rotations per billion year for every part of it.
More so, they believe galazies actually HAVE a rotation speed, but they are not rigid, so they don't. The arms are just standard waves of density not something that moves matter around, all the matter have different rotational speeds depending on how far away from the center they are, otherwise the outer parts would be moving faster than the speed of light.
It's far more likely to be a large macroscopic force beyond gravity than it is some linking between galaxies - it takes many rotations for the rotations of anything to become synchronous with any force and the universe is only old enough that they would have had at most 1-2 rotations since they formed.
They aren't going anywhere fast enough for relativistic effects of time dilation to come into play.
your electric universe nonsense has been debunked many times. Black holes in this universe are electrically neutral, even the stars they came from are. The charged particles emitted from a star, including our sun, are both positive and negative.
The tech community needs to rid itself of this overt bias against electricity in space. We can have a debate over the nuance of whether or not electricity in space does things of importance, but this tradition of calling anybody who even mentions electricity in space a crazy person is increasingly out-of-step with mainstream astrophysical consensus. Astrophysicists increasingly agree that electricity travels through space; what they are trying to suggest is that it doesn't actually do anything of importance. Whether or not that is the case demands that we observe, over time, whether or not we can see evidence that the cosmic plasma is behaving as laboratory plasma (as conductors). This is not something that people will be able to determine without even trying.
This is nonsense. There is no conceivable way for you to connect the premise with the conclusion. But it doesn't really matter, does it? Because any flimsy rationalisation of the so-called "electric universe" hypothesis doesn't need even a sliver of scientific rigour applied to it in order for its proponents to claim it as gospel. It just has to "make sense" in the same way a thousand dead religions used to for their own followers.
Here's an unoriginal thought you might like to plant in your own head: Coming up with an alternative hypothesis for how the universe works is good clean fun, but if you're going to topple "settled science" then your theory has to explain everything we already have good explanations for, not just the few lucky coincidences that happen to "make sense" to some centimeter-scale human intuitions, and it has to explain in *better* levels of detail than what we current have. For everything.
The further we progress in our understanding, the harder and harder it gets have such huge breakthroughs. The deliberate, concerted and competing efforts of thousands of scientists is apparently not quite enough for those YouTubers -- who re-cut ad-infinitum Discovery channel graphics into their bullshit conspiracy videos -- to consider just how fragile their ideas for the cosmos really are.
Each day we get further and further from the times when the work of one man was enough to up-end our understanding of reality. Let alone a man with a dodgy copy of Adobe Premiere, access to the Internet, and a severe case of the Dunning-Krugers. As more than 100 years of progress in the realm of quantum-science keeps pounding into our feeble heads, the way the universe really works is anything but intuitive to a bunch of meat-for-brains hairless apes.
But hey, thanks for "informing" us.
Im wondering how these observations will reflect on how electrically charged black holes tend to be. I've been under the assumption that nearly all black holes tended to be electrically neutral, but then again I'm just an armchair astrophysicist.
Plasma theory does not work here because of the density/temperature disconnect.
Plasma is hot, dense, and without solid clumps of matter (or anti-matter) because elemental particles are too active to coalesce.
In intergalactic space, the near vacuum allows for an atom per cubic meter, which meets the definition of very near absolute zero temperature.
It little behooves the best of us to comment on the rest of us.
Or is that just the rotation rate out where we are (an unfashionable district of the western spiral arm), and the rim takes longer?
I think that's the case. Just like our own sun doesn't rotate uniformly, the interior of a spiral galaxy rotates faster than the outer rim.
Galaxies are not rigid discs, they're made up of particulate matter. Each particle is free to move according to the particular forces acting upon it. Think water swirling the drain rather than a record spinning on a player.
In addition to selection bias, as the summary noted, there is also the matter of sample size, compared to the entire universe. The margin of error would have to be very large.
Also, can one really estimate motion in terms of billion-year cycles from studies conducted over, at most, a few years?
Obviously the Intergalactic Police are making sure they do not travel faster than the posted galactic speed limit.
You're not the keeper of some incredible insight that none of us here has ever thought of.
It is typical, absolutely typical behaviour for people who think they are privy to such incredible revelations to assume that others have not also: thought about them, considered them, investigated them, and subsequently discarded them.
For now (science is fluid) the likelihood of a non-rotating black hole is very slim.
The in-fall of mass in an accretion disk has an angular momentum that will be rotating in unison with other particles in orbit around the event horizon.
Those particles will produce an electromagnetic field.
However, the the electrical charge of the black hole will be neutral.
That same accretion disk will make sure of that.
It little behooves the best of us to comment on the rest of us.
Re: "Plasma is hot, dense"
Somebody needs to alert all of the office building managers who have been using plasma-based lighting (aka "fluorescent lights") above everybody's heads that plasmas are always hot.
You guys are really asking for somebody to document all of the numerous misconceptions which are posted about plasmas into Slashdot comments. The tech community is completely discrediting itself on this subject of cosmic plasmas. Here's some friendly advice: Think about where you learned what you are posting, and if you cannot identify the source, then phrase it as a question.
It all has to do with Gravity, once we figure that out then the rest will fall into place.
Does the universe rotate around the point where the Big Bang happened?
That existence is pretty much what I am expecting some scientist to figure out a long time from now, get supremely depressed, and end it all taking his secrets with him.
So we tell time?
Well no, the Universe tells time, you do practically nothing.
What does he use it for? Wouldn't he always know what time it is?
Mostly just as an accessory, he likes how it looks. I mean you have an iPhone don't you?
Oh my God.
Exactly.
Galaxies are indeed not rigid disks, but the remarkable thing is that your garden-variety spiral galaxy behaves much more like a rigid disk than your angular-momentum-conserving bathtub drain. These rotation rates, by the way, are measured using the Doppler shift observed in spectrographic observations of those galaxies.
It is hypothesized that the "halo" of a spiral galaxy must either contain considerable unobserved "dark matter" or Newton's laws of acceleration and gravitation need a correction term. Most astrophysicists base their work on the Dark Matter explanation, but there are holdouts for MOND (Modified Newtonian Dynamics). So yes, the outer portions of a spiral galaxy have nearly the same rate of angular rotation as in the inner parts, and physical theory needs to account for this conundrum.
I have consistently posted specific technical claims to make my case, and you guys have consistently taken the conversation back to narratives and stereotypes every time.
What if I am the source?
It little behooves the best of us to comment on the rest of us.
"But instead, they discovered a significant population of much older stars mingling with the young stars and gas."
Sounds like an Oscars after-party.
When they came for the communists, I said "He's next door. Take him away. Goddam commies."
Here's a shot of the aurora that you may have missed. Long-range attraction, short-range repulsion. You can derive this from the math. Fluids equations will not be of much help. It's called a Birkeland current.
There is no need to break the rules. All of the interesting things happen without any of that.
Re: "The further we progress in our understanding, the harder and harder it gets have such huge breakthroughs."
Cellular and Molecular Biology 51, 815-820 (2005)
Revitalizing Science In A Risk-averse Culture: Reflections On The Syndrome And Prescriptions For Its Cure
G.H. Pollack
What I've observed over time are a lot of poorly-argued hit pieces which people who claim to believe in peer review immediately adopted as truth. In some cases -- as in the case of Professor Koberlein of RIT -- there have been some glaring errors in his analysis.
For example, this claim he made in that article (below) is completely false, and there is -- to this day -- no retraction observable in the article posted to his own personal blog:
Had he simply googled "electric universe neutrinos", the professor would have run into the EU explanation for solar neutrinos.
Koberlein recently published a redaction -- after four years of refusing to do so -- where he clumsily admitted that this claim is not entirely accurate.
It's interesting that people who claim to believe in peer review are so quick to accept critiques which have not been reviewed by anybody. It's also interesting that Koberlein does not go back and correct the original article, so anybody reading that -- to this day -- would have to sift through all of the comments attached to it in order to understand that a mistake was made. I'm betting that most people don't do that.