Washington State University physicists have created a fluid with negative mass, which is exactly what it sounds like. Push it, and unlike every physical object in the world we know, it doesn't accelerate in the direction it was pushed. It accelerates backwards.
The phenomenon is rarely created in laboratory conditions and can be used to explore some of the more challenging concepts of the cosmos, said Michael Forbes, a WSU assistant professor of physics and astronomy and an affiliate assistant professor at the University of Washington. The research appears today in the journal Physical Review Letters, where it is featured as an "Editor's Suggestion."
Hypothetically, matter can have negative mass in the same sense that an electric charge can be either negative or positive. People rarely think in these terms, and our everyday world sees only the positive aspects of Isaac Newton's Second Law of Motion, in which a force is equal to the mass of an object times its acceleration, or F=ma. In other words, if you push an object, it will accelerate in the direction you're pushing it. Mass will accelerate in the direction of the force.
takyon: Just what I needed for my Alcubierre drive?
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Physicists Say They've Created a Device That Generates 'Negative Mass'
Physicists have created what they say is the first device that's capable of generating particles that behave as if they have negative mass. The device generates a strange particle that's half-light/half-matter, and as if that isn't cool enough, it could also be the foundation for a new kind of laser that could operate on far less energy than current technologies.
This builds on recent theoretical work on the behaviour of something called a polariton, which appears to behave as if it has negative mass – a mind-blowing property that sees objects move towards the force pushing it, instead of being pushed away.
Now physicists from the University of Rochester have created a device that allows them to actually create these polaritons at room temperature. They do this by manipulating captured photons and combine them with a kind of quasi-particle called an exciton to make something half-light/half-matter that some scientists affectionately refer to as 'magic dust'.
This alone is "interesting and exciting from a physics perspective," says quantum physicist Nick Vamivakas from Rochester's Institute of Optics. "But it also turns out the device we've created presents a way to generate laser light with an incrementally small amount of power."
Anomalous dispersion of microcavity trion-polaritons (open, DOI: 10.1038/nphys4303) (DX)
Previously: Physicists Create 'Negative Mass'
(Score: 4, Insightful) by frojack on Tuesday April 18 2017, @04:26AM (2 children)
Who Knew?
No, you are mistaken. I've always had this sig.
(Score: 1, Touché) by Anonymous Coward on Tuesday April 18 2017, @05:27AM
WTF, SN?
(Score: 0) by Anonymous Coward on Tuesday April 18 2017, @06:18AM
and it won the election
(Score: 1, Funny) by Anonymous Coward on Tuesday April 18 2017, @04:28AM (4 children)
Every Catholic is familiar with a negative mass.
(Score: 3, Funny) by Anonymous Coward on Tuesday April 18 2017, @06:22AM (3 children)
I looked into that and found nun.
(Score: 1, Funny) by Anonymous Coward on Tuesday April 18 2017, @06:30AM
... there's a whole HOST of examples.
(Score: 2) by bob_super on Tuesday April 18 2017, @07:51AM
Look for small debris, I heard it pope.
(Score: 2) by Thexalon on Tuesday April 18 2017, @04:14PM
It may make you cross, but keep monkeying around and you'll find it.
The only thing that stops a bad guy with a compiler is a good guy with a compiler.
(Score: 0) by Anonymous Coward on Tuesday April 18 2017, @04:58AM (1 child)
...and does it taste good? Asking for a friend.
(Score: 0) by Anonymous Coward on Tuesday April 18 2017, @01:26PM
In theory, yes???
If we just plug a negative number into $f = \frac{G m_1 m_2}{r^2}$, we get a negative $f$ and thus acceleration out of a gravity well, right?
So, your friend will weigh less, certainly, but he'll still be a fatass. :(
You'll need to wait until there's something that can be digested by humans that creates an endothermic process, no?
But we might get actual hoverboards! :)
(Score: 0) by Anonymous Coward on Tuesday April 18 2017, @06:01AM (2 children)
Is this like when you have a digital weight and you're so fat your mass causes an integer overflow?
(Score: 2) by frojack on Tuesday April 18 2017, @08:54AM
Yer momma...
No, you are mistaken. I've always had this sig.
(Score: 2) by Wootery on Wednesday April 19 2017, @11:31AM
There's a reason they weigh ships by their displacement of water, rather than on scales.
Use the floating approach and your overflow issue disappears.
(Score: 3, Informative) by Anonymous Coward on Tuesday April 18 2017, @06:03AM (5 children)
If you create a time crystal out of negative mass material, did you know that a blue police box suddenly arrive?
Article is a bunch of handwavy bullshit, just like time crystals and just like the title of this comment.
What they appear to have actually created is a non-newtonian fluid out of a Bose Einstein condensate.
https://en.wikipedia.org/wiki/Non-Newtonian_fluid [wikipedia.org]
(Score: 5, Informative) by NotSanguine on Tuesday April 18 2017, @06:36AM (4 children)
What AC said.
From TFA:
"Blimey! It's smaller on the outside!"
No, no, you're not thinking; you're just being logical. --Niels Bohr
(Score: 0) by Anonymous Coward on Tuesday April 18 2017, @08:00AM (2 children)
> if behaves as if it has negative mass.
Does nobody notice the if (there is even 2 of them....)?
It seems to me this is not really negative mass, it just behaves as negative mass would behave, seemingly because of some thermodynamic, but not gravitational, force.
But perhaps a physicist can clarify?
(Score: 4, Interesting) by VLM on Tuesday April 18 2017, @12:25PM (1 child)
About 8 years ago PRL had an article titled "Mass of a Spin Vortex in a Bose-Einstein Condensate"
https://arxiv.org/pdf/0902.3685.pdf [arxiv.org]
might be somewhat enlightening. Its a theory paper from about 8 years ago which sounds similar to the experimental results.
(Insert ridiculous levels of hand waving here that would make the paper author cringe if they ever saw it) If you make a vortex in a super fluid its kinda stable which is really weird but well known ish. The vortex itself has a moment of inertia and stores rotating energy and has what boils down to a mass it takes force to mess with a vortex just like it takes peculiar forces depending on rotating speed to mess with a spinning gyroscope which could be abstracted at least instantaneously into a model of just a lump of very heavy metal with a weird moment of inertia shape that isn't rotating. It turns out that superfluid vortexes as they get messed with can under weird circumstances wiggle about on an instantaneous basis as if they were a solid block of steel with negative mass. They aren't of course, the apparatus doesn't lift up into space, but an abstract simulated instantaneous predictive model has a negative number for mass so people get all wound the hell up about it.
An interesting example of negative mass mostly outside this discussion is some hall effect thing where holes wander about as if they are things (rather than lack of things...) that wander about as if they (they as in the hole) have a negative mass.
Another example of negative things that piss people the heck off, is its very easy to build circuitry that essentially emulates a negative resistance. I'll be damned you lower the input voltage and the current goes up what manner of witchcraft is this begone evil spirit. Of course this is merely a boring as hell switching power supply behavior. You graph the behavior of a resistor on a P-I graph paper and you get a hopefully perfectly straight line of a positive resistance welcome to ohms law (although real world resistors do vary with voltage and quite a bit sometimes and also vary with current LOL but close enough to linear most of the time). You graph a nice 100 watt switching power supply with various incoming voltage and current and WTF the damn thing on the graph has a negative resistance. of course the atoms that make it up are entirely positive resistance on a small enough scale... the negative lives in the design of the supply in the system itself. Sorry no bad SN automobile analogy but I did provide you a nice EE analogy so thats not so bad.
In a sense if you were a fish and defined space as having a density of 1 gram per mL which is about right enough for seawater (to one sig fig anyway) and you worked out all manner of gravitational theory you'd be confused as hell about cavitation bubbles if you ever saw one. So water has a density of zero and this "hole in the water" has a density of -1 grams per mL wtf? And you only get cavitation bubbles by spinning a propeller faster than the speed of sound essentially? Weird.
The whole topic is sort of like trolling/provoking people using the light year long scissors and no part of the scissors ever moves faster than 1 m/s but the intersection point of the two blades can move an arbitrary multiple of the speed of light by getting the angle just right.
As for what to do with something that isn't flubber but behaves like it in a certain sense, well, I bet you could make a rube goldberg like seismometer or maybe a gravity wave meter out of a great big volume of it. I wonder if you could tune the virtual mass of a vortex to have very low measurable mass and then very small nearby contaminants like neutrinos would throw it out of balance tada you have a magic nuclear submarine detector. Of course the Navy probably invented, classified, and deployed this 30 years ago but if I disappear, at least you'll know why. It seems like the kind of thing that would be self evident and the magic is all in the engineering, kind of like a nuke, actually.
(Score: 2) by art guerrilla on Tuesday April 18 2017, @01:19PM
whoa, okay...
so was that the blue crystal meth, then ? ??
(Score: 2) by kaszz on Tuesday April 18 2017, @01:15PM
So no closer to the Alcubierre drive then..
Hopefully they succeed to get some data that can improve knowledge to accomplish it though.
(Score: 0) by Anonymous Coward on Tuesday April 18 2017, @06:33AM (2 children)
Now all we need is a bipolar genius who survives a world war, loses faith in humanity, and builds a warp ship because he has nothing to live for and nothing else to do. Despair is the motivator of invention.
(Score: 4, Funny) by Soylentbob on Tuesday April 18 2017, @07:06AM (1 child)
Despair is the motivator of invention.
Ahh! So that's how he makes America great again. And no one would be more effective.
(Score: 0) by Anonymous Coward on Tuesday April 18 2017, @01:30PM
Well, it's a great way to get the Eugenics War started seeing as how we're 20-some-odd years behind schedule in this timeline!
(Score: 4, Insightful) by Snospar on Tuesday April 18 2017, @08:10AM (2 children)
I was hoping for some cool material that would exhibit anti-gravity and end up stuck to the ceiling.
They only managed to tick the "cool" box.
Huge thanks to all the Soylent volunteers without whom this community (and this post) would not be possible.
(Score: 2) by c0lo on Tuesday April 18 2017, @11:01AM
Bah, rubidium! - you only need a dilettante cook to prepare a stir fry for you
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by Rivenaleem on Wednesday April 19 2017, @03:27PM
Well strictly speaking they ticked the super cool box, having created a Bose Einstein Condensate.
(Score: 3, Funny) by inertnet on Tuesday April 18 2017, @08:29AM (1 child)
We have a couple of negative masses here on SN, pushing others the wrong way.
(Score: 2) by FatPhil on Tuesday April 18 2017, @09:20AM
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 3, Informative) by opinionated_science on Tuesday April 18 2017, @10:07AM (3 children)
This has been known about liquid Helium for, well, since *I* was at school.
Helium has a tendency to climb out of beakers...
And it isn't "negative mass" no matter what the clickbait engine that is "sciencedaily" says - it would clearly float away....
I know that science fiction is cool, and that perhaps someday we'll get warp engines, but please at least apply some critical thought to declarations that might be a bit too amazing...
(Score: 0) by Anonymous Coward on Tuesday April 18 2017, @01:20PM
God, I hate "Internet experts."
(Score: 1, Informative) by Anonymous Coward on Tuesday April 18 2017, @01:40PM
It is more subtle than you think. This isn't just an observation or restatement of superfluidity. It is a demonstration of negative effective mass by setting up a Bose-Einstein condensate such that they exhibit a negative dispersion relation, much like how metamaterials are set up such that they exhibit a collective negative index of refraction. Liquid helium was used here because it is a system that is easy to tailor hydrodynamic parameters.
(Score: 2) by jimtheowl on Thursday April 20 2017, @02:02AM
To quote:
".. the rubidium superfluid has regular mass. Breaking the bowl will allow the rubidium to rush out, expanding as the rubidium in the center pushes outward.
"To create negative mass, the researchers applied a second set of lasers that kicked the atoms back and forth and changed the way they spin. Now when the rubidium rushes out fast enough, if behaves as if it has negative mass. ''Once you push, it accelerates backwards".."