Bizarre 'dark fluid' with negative mass could dominate the universe – what my research suggests
It's embarrassing, but astrophysicists are the first to admit it. Our best theoretical model can only explain 5% of the universe. The remaining 95% is famously made up almost entirely of invisible, unknown material dubbed dark energy and dark matter. So even though there are a billion trillion stars in the observable universe, they are actually extremely rare.
The two mysterious dark substances can only be inferred from gravitational effects. Dark matter may be an invisible material, but it exerts a gravitational force on surrounding matter that we can measure. Dark energy is a repulsive force that makes the universe expand at an accelerating rate. The two have always been treated as separate phenomena. But my new study, published in Astronomy and Astrophysics, suggests they may both be part of the same strange concept – a single, unified "dark fluid" of negative masses.
Negative masses are a hypothetical form of matter that would have a type of negative gravity – repelling all other material around them. Unlike familiar positive mass matter, if a negative mass was pushed, it would accelerate towards you rather than away from you.
[...] My model shows that the surrounding repulsive force from dark fluid can also hold a galaxy together. The gravity from the positive mass galaxy attracts negative masses from all directions, and as the negative mass fluid comes nearer to the galaxy it in turn exerts a stronger repulsive force onto the galaxy that allows it to spin at higher speeds without flying apart. It therefore appears that a simple minus sign may solve one of the longest standing problems in physics.
(Score: 3, Interesting) by acid andy on Thursday December 06 2018, @09:20PM (10 children)
Isn't a negative mass the missing piece we need to make an Alcubierre drive possible?
If a cat has kittens, does a rat have rittens, a bat bittens and a mat mittens?
(Score: 2) by JoeMerchant on Thursday December 06 2018, @09:24PM (3 children)
Good luck getting your hands on any:
🌻🌻 [google.com]
(Score: 0) by Anonymous Coward on Thursday December 06 2018, @09:41PM
(Score: 3, Interesting) by acid andy on Thursday December 06 2018, @09:49PM
I wonder if you could ionize it and then attract it magnetically.
If a cat has kittens, does a rat have rittens, a bat bittens and a mat mittens?
(Score: 3, Interesting) by Immerman on Thursday December 06 2018, @10:52PM
True, however, since it has negative mass, a repulsive force will actually pull it towards you. -F = (-m)*a
Of course, it repels you with an equal force, but if you're pulling it in from all directions that cancels out.
Then you can capture it in a huge bottle, set it behind your space ship, and allow the repulsive force to accelerate you both in the same direction indefinitely.
Negative mass is weird, and there's several models out there that vary as to whether it's gravitational or inertial mass that's negative, or both. In this case they're clearly talking about both, since it's supposed to be attracted to the mass of a galaxy, while simultaneously pushing the stars inward. Presumably this stuff is spread all through the galaxy as well, but with a density that plateaus at some point as self-repulsion balances out the attractive effect of the normal matter.
(Score: 2) by DannyB on Thursday December 06 2018, @10:50PM (2 children)
No. It's the thing we need to make the next diet drink possible.
The lower I set my standards the more accomplishments I have.
(Score: 5, Funny) by fyngyrz on Friday December 07 2018, @12:08AM (1 child)
Negative mass is what you get when you're not Catholic.
--
Money can't buy love, but it can sure buy a yacht to pull up next to it on.
(Score: 1, Funny) by Anonymous Coward on Friday December 07 2018, @04:17AM
I'd be careful if I were you. The Catholic Church has missals.
(Score: 4, Interesting) by Fluffeh on Thursday December 06 2018, @11:20PM
The only way that they could theoretically satisfy some of the equations was to use matter with a negative mass, yes.
(Score: 2) by legont on Friday December 07 2018, @01:24AM (1 child)
Yes! The whole mystery of the universe - increasing expansion again after slowing down - is blamed on bloody aliens commute habits at super-light speeds. See, the suckers create space and use the proceedings for fuel without any considerations for future generations of intelligent life forms who will be farther and farther from each other. Truly global
warmingenlargement crime in progress."Wealth is the relentless enemy of understanding" - John Kenneth Galbraith.
(Score: 0) by Anonymous Coward on Friday December 07 2018, @09:34PM
Bah! Another Federation commie going on about anthropogenic subspace breakdown. It's all a left-wing plot to steal from hard-working Ferengi, while you fly from one end of the quadrant to the other in a private galaxy-class cruiser!
(Score: 2) by JoeMerchant on Thursday December 06 2018, @09:21PM (2 children)
And, for real fun, what if the dark fluid is composed of effective anti-matter - if we ever actually touch any of it, we annihilate in an invisible implosion...
-----
Traveling through hyperspace ain't like dusting crops, boy! Without precise calculations we could fly right through a star or bounce too close to a supernova and that'd end your trip real quick, wouldn't it?
🌻🌻 [google.com]
(Score: 2) by Immerman on Thursday December 06 2018, @10:55PM
Then we wouldn't be here to talk about it, since the galaxy would already be jam-packed with the stuff with a density limited only by its self-repulsion
(Score: 2) by PiMuNu on Friday December 07 2018, @02:44PM
It can't be antimatter - it is charge neutral, otherwise it would interact electromagnetically and would not be "dark". Charge non-conservation has never been observed, so it can't "annihilate" as normal antimatter would.
(Score: 2) by acid andy on Thursday December 06 2018, @09:47PM (2 children)
I'm trying to imagine this. If you push against it, you're already extremely close to it, so if it accelerates towards you, does that mean it's pushing back against your hand harder than the normal equal and opposite reaction (probably double)? Or would it just pass right through your hand and head off into the distance behind you?
If a cat has kittens, does a rat have rittens, a bat bittens and a mat mittens?
(Score: 2) by DannyB on Thursday December 06 2018, @10:53PM
It seems like if it repels, then something that starts to push it causes it to move in the direction of push before physical contact is made.
The lower I set my standards the more accomplishments I have.
(Score: 3, Informative) by Immerman on Thursday December 06 2018, @11:09PM
The trick is that there's no such thing as contact forces - everything is actually energy fields pushing against each other, so you can always get closer, until the energy fields balance out.
More generally, think about what happens when you push on something normally - you accelerate away from it, and it accelerates away from you, so it's rapidly out of reach and the pushing stops. If you push on a negative mass though, what happens is you accelerate away from it, and it accelerates towards you, so you remain in contact indefinitely. At least assuming you're the same absolute mass. If its absolute mass is lower than yours then you will accelerate away, while it accelerates towards you even faster, pushing on you harder, causing you both to accelerate faster, in an ever-accelerating spiral that's unlikely to end well.
Fortunately in this case they're proposing it as an alternative for dark matter, which likely means it doesn't interact with normal matter except through gravity, and can pass right through you without interacting.
(Score: 5, Insightful) by insanumingenium on Thursday December 06 2018, @09:55PM (19 children)
I hear an awful lot about dark matter and energy, and now apparently fluid. As far as I can see from the outside, these exist only to avoid saying "We don't have a theory which explains measured galactic rotation and expansion".
If they were simply offered as potential (and perhaps tenuous given the lack of any positive evidence) explanations that would be one thing, but the idea that only 5% of mass is visible is touted as proven fact widely enough that I regularly encounter it.
And as far as I can tell (again not a physicist, and I don't play one on TV) their greatest value is as a target to try and disprove, it doesn't seem to me like these theories add any predictive abilities or other value to our models nor offer insight to how anything actually works. It doesn't seem like they will be getting (or likely can get) any direct testing. I have never seen anything that offers any reason for dark whatever to be preferable to (insert deity here) as an explanation for the shape of the cosmos.
So, what am I missing?
(Score: -1, Flamebait) by Anonymous Coward on Thursday December 06 2018, @10:09PM (2 children)
Welcome to Millennial Science where a fertile imagination is just as important as testable hypotheses. To draw an analogy: in the real world, you can observe only two genders but millennials hypothesize that there are actually 72 genders.
(Score: 1, Offtopic) by Azuma Hazuki on Friday December 07 2018, @01:15AM
Tell me something...why do you feel the need to work this into like every single thread on the site, even when it's completely off-topic? Are you repressing something about yourself? You seriously talk about this more than Kurenai, who *is* trans.
I am "that girl" your mother warned you about...
(Score: 2) by hendrikboom on Friday December 07 2018, @09:54AM
Where did that 72 come from? Did you just make it up?
(Score: 1, Interesting) by Anonymous Coward on Thursday December 06 2018, @10:15PM (5 children)
You are missing nothing. Look into MOND, they predict all sorts of stuff exactly with no free parameters (although there is some freedom due to uncertain data-dependent ones): https://tritonstation.wordpress.com/ [wordpress.com]
Now, MOND is more of an empirical relationship that remains to be explained than a theory per se. However, any theory is going to have to explain MOND and it simply seems impossible that dark matter could do this.
(Score: 1, Interesting) by Anonymous Coward on Thursday December 06 2018, @10:24PM (4 children)
This article is especially good: https://tritonstation.wordpress.com/2018/07/26/a-brief-history-of-the-acceleration-discrepancy/ [wordpress.com]
As the data gets cleaner, it fits the predictions of MOND better and better. Amazing.
(Score: 2) by Immerman on Thursday December 06 2018, @11:52PM (3 children)
To be clear, MOND offers no predictions or explanations - it's just a description of the observed galactic rotation curves, not an attempt to explain them. The only "predictive" quality it has is that newly measured galaxies will have the same observed rotation curve as previously measured ones. And it's plagued by that one big unknown "falloff function" that makes the whole thing rather squishy. I don't recall even seeing any rough estimates for it, without which MOND can describe pretty much any rotation curve observed, making it valueless.
There are various MOND-based theories that interpret the description in various ways - is it the attractive force of gravity that goes non-inverse-square at low accelerations? Or the relationship between force and acceleration? Or something else entirely? They all start at the simple descriptive formula supplied by MOND, and then go off in various different directions from there.
(Score: 0) by Anonymous Coward on Friday December 07 2018, @12:18AM (2 children)
Sorry, but you basically have no knowledge of MOND,
Here is a prediction (not post-diction) using MOND for the CMB spectrum. It got the second peak exactly with no free parameters: https://core.ac.uk/download/pdf/25263787.pdf [core.ac.uk]
I don't even want to bother explaining further to someone harboring so much misinformation.
(Score: 2) by Immerman on Friday December 07 2018, @01:09AM (1 child)
So, do they finally have an estimate for the critical acceleration and falloff function? Last time I checked they had neither - without which you could describe literally *any* galactic rotation curve.
(Score: 0) by Anonymous Coward on Friday December 07 2018, @01:46AM
I have no idea what you are trying to refer to.
It has always been that MOND becomes apparent at around a0 = 10^-10 m/s^2 (https://en.wikipedia.org/wiki/Modified_Newtonian_dynamics). And yes, MOND has been used to fit every galatic rotation curve based on the amount of light emitted with no free parameters. It does not fit non-existent galaxies though.
(Score: 2, Interesting) by khallow on Thursday December 06 2018, @10:20PM (2 children)
Fluid is used here in a very generic way. They're just saying that they can model the "negative mass" as a fluid. In a similar sense, stars of a galaxy or sand in a jar are fluids.
One important prediction of such models is that the effect scales with the concentration of the negative mass which is implied in this story to vary. That means we should see galaxies with more and less of the gravitational anomalies that we're having so much trouble with. There does seem some mild support [soylentnews.org] for that. OTOH, if it's a universal effect (say that space is just curved that way and there is no negative energy at all), then you won't see such variations.
(Score: 3, Interesting) by Gaaark on Thursday December 06 2018, @10:39PM (1 child)
Hey, a shout-out! Thanks! :)
But DARPA is supporting him a well
https://earthsky.org/space/rocket-thrust-quantized-inertia-qi-darpa-funding [earthsky.org]
--- Please remind me if I haven't been civil to you: I'm channeling MDC. ---Gaaark 2.0 ---
(Score: 1) by khallow on Friday December 07 2018, @12:38AM
(Score: 2) by nobu_the_bard on Thursday December 06 2018, @10:32PM (2 children)
My understanding is something like this: there's very good data on the total mass and energy of the universe, based on measurements about the relative speed of observable objects, which among other things allowed us to determine something like the big bang happened and what processes it involved. The data comes from many sources but includes measuring things like blueshift in light reaching us, measuring how objects interfere with the light, etc.
The problem is, the difference between what we can observe and what we calculate must exist, has a very large discrepancy. We've gathered a ton of data about how the universe is structured only to find seemingly the part we can interact with is actually very tiny. "Dark Matter" is a term used to describe all of the stuff we can't measure yet.
Since we have no way of measuring it, we have no idea what it is. Trying to guess what it is might give someone an idea about how to measure it if nothing else.
There are a couple of theories that would allow dark matter to not be anything exotic - maybe it's all just shuffled off someplace without any stars, and somehow is letting the light of other stars through it, for example - but it's tough to believe you could get that much ordinary matter together without things like stars showing up or interfering with our view of the other stars, under our current understanding.
Anyway, as for some of the more wild theories... well if you can't actually find anything and need to convince people you should be funded...
(Score: 4, Insightful) by fyngyrz on Friday December 07 2018, @12:15AM (1 child)
Or it's a term for a catchall that is trying to make up for lacks in our theoretical understanding of physics and/or circumstances we have yet to grasp.
When the theory doesn't fit the data, it doesn't always have to mean that the data is wrong. Sometimes it's the theory.
--
The 3 Functional Retardations:
traditional, jingoistic, and religious.
(Score: 2) by insanumingenium on Friday December 07 2018, @05:10PM
See if that seemed to be the usage it would make more sense. If dark matter was just code for "here there be dragons" it would confuse me so much less. But the insistence I see over and over, even the summary above, takes the conclusion that dark matter represents 95% of the actual mass in the universe literally.
(Score: 5, Informative) by Gaaark on Thursday December 06 2018, @10:33PM
You're missing nothing: check out
https://physicsfromtheedge.blogspot.com/ [blogspot.com]
https://www.nextbigfuture.com/2018/09/darpa-funds-developing-quantized-inertia-into-breakthrough-space-propulsion.html [nextbigfuture.com]
https://earthsky.org/space/rocket-thrust-quantized-inertia-qi-darpa-funding [earthsky.org]
Better than MOND as there are no fudgeable data/adjustable parameters. It just works, and he got a large amount of funding to pursue it.
REAL science, not 'dark matter because we have no idea' science.
--- Please remind me if I haven't been civil to you: I'm channeling MDC. ---Gaaark 2.0 ---
(Score: 3, Interesting) by bob_super on Friday December 07 2018, @12:19AM (1 child)
The problem is that the theories are really really good at explaining almost everything we can observe ... except missing a quantity of mass.
If you add Dark Matter (now Fluid) to the universe theories, you can explain so much, and verify it it's really hard to just say "this whole thing is completely wrong because it doesn't work unless I add Dark Matter"
It's wrong because it needs some imaginary construct (call it Phlogiston or Aether, wink wink) to deal with that one piece which doesn't work. But it works for almost everything else in a way that no other theory comes even close.
Until we figure out that missing piece of math or mass, that's the best we got, but non-lazy journalists and authors should always explain what it means rather than throw it out as a certainty.
(Score: 2) by insanumingenium on Friday December 07 2018, @05:03PM
That matches pretty well with my understanding, the crux of my confusion is that the tested and very reliable model stands even when incomplete, why do we need to claim to know something we don't to complete it?
To the best of my knowledge dark matter in particular gives no new insight, no new way to test the laws of nature, it seems totally valueless. The search for the missing math or mass is important and worth our time, but starting from the supposition that that mass must exist gets us dark energy as a bodge to the bodge, and now an assumption that 95% of the mass and 68% of the total energy of the universe are mysteriously hidden from us. Now perhaps that is a misconception on my part, I have always heard dark matter necessitates dark energy, but does the standard model still need dark energy to explain expansion without dark matter? My previous understanding was that it didn't, which is pretty central to my confusion with this whole process.
And starting from a wild hypothesis and seeing where that theory takes you can absolutely be of value, I just don't understand how this particular theory achieved the consensus it seems to have.
I have seen a very uniform acceptance of dark matter and energy, and the only people I see searching for math not mass seem to be relegated to fringe. Likely that observation is bad, but I suspect that there is some kernel of what makes "dark matter is 95% of the total mass of the universe" preferable to "no model consistent with current science explains the rate of galactic rotation" that I am just plain missing.
(Score: 2) by Nobuddy on Friday December 07 2018, @08:22PM
Dark matter/dark energy are placeholders. Something exists, but we lack the capability to observe it. It is, most likely, a lot of things that are simply beyond out capability to measure. "Dark" because we cannot 'see' it with any instruments we currently have.
We will likely eventually figure out a way to measure in different ways, and more of it will be visible to us, and be categorized. The amount of "dark" will reduce each time. Maybe it will get to zero some day. Maybe some will be forever beyond our ability to see.
(Score: 0) by Anonymous Coward on Thursday December 06 2018, @10:03PM (2 children)
Who funds this nonsense? Real science is based on observations and experiments, not taking mushrooms and imagining "negative masses".
(Score: 3, Funny) by Runaway1956 on Thursday December 06 2018, @11:21PM
Who funds this? Must be the Russians.
(Score: 0) by Anonymous Coward on Friday December 07 2018, @08:05PM
"Real science is based on observations and experiments"
Then this is real science, a hypothesis that explains the OBSERVED phenomena of galaxies rotating faster than expected and space expansion .
Now you are free to shoot down the hypothesis with anything .... Except name calling.
(Score: 0) by Anonymous Coward on Friday December 07 2018, @04:27AM
Or not.
Down with weasel words
(Score: 1) by JoeBakhos on Friday December 07 2018, @04:50PM
I propose that gravity reverses and becomes repulsive at approximately 1.5 million light years. It becomes more and more strongly repulsive, reaches a peak, and then decreases trailing off to zero.
This does away both with dark matter and also dark energy. It would explain why most galaxies are accelerating away from each other – leaving no need for cosmological expansion or dark energy.
It also explains gravitational rotational rates without the need of dark matter. Galaxies are pushing dust and gas into the interstitial space between galaxies. This dust and gas means that each galaxy or small galaxy cluster is surrounded by a womb of material at a distance that repulsive gravity operates. This repulsive womb, along with the pressure from other galaxies, holds outer stars in place, explaining higher than expected rotation.
You may read the justification for this theory here, along with responses to objections at the bottom:
https://www.reddit.com/r/MyTheoryIs/comments/87pcgq/what_dark_matter_is/ [reddit.com]
I think that General Relativity can be adjusted such that we keep time dilation, BUT ditch curved or dilated space. I.e. we should work with flat, 3D , Euclidean space + time dilation. I explain about this in the notes at the bottom of the article.