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'
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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?
(Score: 2) by hemocyanin on Tuesday January 16 2018, @02:52AM (21 children)
Does it scale up? Does that mean a massively powerful laser with a large amount of energy?
(Score: 4, Interesting) by Arik on Tuesday January 16 2018, @02:58AM (18 children)
If laughter is the best medicine, who are the best doctors?
(Score: 3, Informative) by frojack on Tuesday January 16 2018, @02:58AM (1 child)
Flubber?!!
No, you are mistaken. I've always had this sig.
(Score: -1, Spam) by Anonymous Coward on Tuesday January 16 2018, @03:20AM
What's this!? A vision!? A vision of what? A vision of the future. I can see it. I can see the future of your ass. I'm the Assteller.
You're relaxing at home when all of a sudden you're instantly transported to a mysterious location. It looks like some kind of large, dark cavern, and it's so large that you can't see any walls. You then realize that the floor is made out of stuffing, like you'd see in a pillow. A voice from an unknown source then said, "The Stuffing is a nice place! It's warm, it's stuffy, and there's parades all around!" Right after that, you notice a parade in the distance, and decide to go there.
You party down in the parade for a long time, but then you realize that you got lost and can no longer find it. You wandered away from the parade without realizing it. A feeling of dread bubbles up from the depths of your being. You have to find the parade. You can't remain in this place for too long; it's dangerous. Something is targeting you. You see countless lumps under the stuffing on the floor. Numerous beings are crawling towards you.
What do you do? When you try to run, you can barely move, as if something is preventing you from sprinting at normal speed. So you decide to slam your ass down on the lumps as if your ass is a meteor! After doing so, all the lumps have vanished from existence. You proclaim your victory, but can't get rid of the feeling that something is wrong.
Then it hits you. The tickle. Those lumps were actually evil children's toys crawling under the stuffing, and they got sucked right up your butt. These toys are now slamming into the walls on the inside of your ass! It tickles, stop! No! You think about rubbing dirt in your face, but there is no dirt to be found. Countless more lumps make their way towards your body, and you can do nothing but watch them get sucked into your ass! The tickle intensifies to the point where it makes the previous level of tickle look like a joke. You begin screaming incoherently, but your ass continues to be used as a bouncehouse...
(Score: 5, Informative) by takyon on Tuesday January 16 2018, @02:59AM (4 children)
It also sounds a whole lot like what the Alcubierre drive [wikipedia.org] needs to work, but I wouldn't get your hopes up just yet.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 4, Funny) by Anonymous Coward on Tuesday January 16 2018, @04:39AM (1 child)
Now all we need is a bipolar drunk to go off his meds, build a warp drive for real, and panic when he realizes his work will make him more famous than he wants to be.
(Score: 1, Interesting) by Anonymous Coward on Tuesday January 16 2018, @01:59PM
Hopefully he'll have a shotgun ready. A warp signature is going to light up so many long-range probes, and alien invaders are certain to follow the craft back to Earth. Hopefully he realizes this, shoots them on the gang plank, and takes their ship so we can understand what kind of technology those green-blooded hobgoblins are planning to use to enslave us.
It could be the dawn of a glorious new empire!
(Score: 1, Insightful) by Anonymous Coward on Tuesday January 16 2018, @07:44AM (1 child)
these things have negative mass just as much as air bubbles in water have negative mass.
so you may as well use air bubbles for your alcubierre drive.
(Score: 3, Funny) by takyon on Tuesday January 16 2018, @01:12PM
As long as I can get the initial coin offering for WarpCoin going, sure thing.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 3, Interesting) by maxwell demon on Tuesday January 16 2018, @07:41AM (4 children)
Unfortunately polaritons are actually quasiparticles. That is, they are not really particles (such as, you cannot pull them out of the material and send them somewhere in space), but they only exist as states of the material that behave as if they were particles. And the material still has positive mass (and positive gravitation).
The Tao of math: The numbers you can count are not the real numbers.
(Score: 3, Interesting) by Arik on Tuesday January 16 2018, @11:09AM (3 children)
Umm, ok. It would still be reduced mass, no?
If laughter is the best medicine, who are the best doctors?
(Score: 3, Interesting) by maxwell demon on Tuesday January 16 2018, @12:14PM (2 children)
Depends. Reduced mass compared to what?
In any case, compared to the mass of the material as such, all those masses are negligible (as in, the mass difference will be below anything measurable with scales).
The Tao of math: The numbers you can count are not the real numbers.
(Score: 3, Interesting) by Arik on Tuesday January 16 2018, @12:21PM (1 child)
Reduced mass compared to the same material minus the quasi-particles which have negative mass.
If laughter is the best medicine, who are the best doctors?
(Score: 5, Interesting) by maxwell demon on Tuesday January 16 2018, @12:45PM
Since you have to add a photon (positive energy), you end up with a state that has more total energy, and thus more total mass (as E=mc²). The negative mass is only the effective mass of the quasiparticle describing its movement relative to the material. It is mostly unrelated to the real mass that enters the inertia/gravity of the material as a whole.
As an example, take the most common (and most easy to understand) quasiparticle: The hole. The hole is just a missing electron, no electron sitting where an electron should be. No electron of course has less real mass than one electron. Yet a hole has a positive effective mass; it behaves exactly as if there were a particle with positive mass and opposite charge sitting in that place (and indeed, the mass can even differ depending on the direction the hole moves!).
The Tao of math: The numbers you can count are not the real numbers.
(Score: 2) by FatPhil on Tuesday January 16 2018, @09:16AM (3 children)
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by Immerman on Tuesday January 16 2018, @02:42PM (2 children)
Maybe. There's a actually a lot of speculation on what exactly negative mass would imply, with most models dismissed as extremely unlikley because, like your example, they would break conservation of energy and/or momentum.
(Score: 2) by hendrikboom on Wednesday January 17 2018, @03:34AM (1 child)
They don't break conservation of energy or momentum. The increased kinetic energy of the positive mass is exactly balanced by the negative kinetic energy of the negative mass. Likewise for momentum. The negtive mass has momentum pointing in the opposite direction to where it's moving.
(Score: 2) by Immerman on Wednesday January 17 2018, @02:07PM
Hmm, you're right. So perhaps not - my gut says it would not be terribly difficult to "game the system", but intuition may readily misfire when you change fundamental assumptions.
(Score: 2) by stormreaver on Tuesday January 16 2018, @02:48PM
That's the first thing my crossed my mind. A particle that pushes towards the force of gravity, rather than away from it, would be one of the greatest physics achievement in all of human history.
(Score: 2) by HiThere on Tuesday January 16 2018, @06:08PM
It sounds like it, but read the article. The "particles" that they are talking about are excitrons, i.e. in an unstable excited state. It's quite interesting, and it might well lead to a better laser pumping system, but don't read too much into this. You need quite controlled conditions to create it, and it's still only meta-stable...and closer to unstable than to stable.
The equipment needed to generate this might well be miniturizable, but it will guaranteed be quite massive compared to the "negative mass" produced. And the process of making it eats energy, as you would expect if you were pumping a laser.
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 3, Interesting) by takyon on Tuesday January 16 2018, @02:58AM (1 child)
You could always use multiple lasers [soylentnews.org]. Maybe even millions of chip-scale lasers.
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(Score: 4, Funny) by coolgopher on Tuesday January 16 2018, @05:22AM
It's as if a million lasers cried out at once... no wait... >.>
(Score: 5, Funny) by frojack on Tuesday January 16 2018, @02:58AM
Walter looked into the jar, but could see nothing. He removed the cover to get a better view, and a slight breeze ruffled his hair, but he could still not find the magic dust. He tried another jar. Then another, and another. Finally, after the last jar, he figured out that they guys in the lab were pulling a gag on him and stomped off to his basement lab.
No, you are mistaken. I've always had this sig.
(Score: 2) by JoeMerchant on Tuesday January 16 2018, @04:04AM (13 children)
One problem I see with negative mass particles is that they would tend to scatter, sort of like electrons, but without protons to reel them in.
🌻🌻 [google.com]
(Score: 2) by arcz on Tuesday January 16 2018, @04:44AM (3 children)
(Score: 2) by frojack on Tuesday January 16 2018, @05:16AM (2 children)
Let there be light
"But it also turns out the device we've created presents a way to generate laser light with an incrementally small amount of power."
No, you are mistaken. I've always had this sig.
(Score: 0) by Anonymous Coward on Tuesday January 16 2018, @07:44AM (1 child)
Now, this would really be something... a dark light. Instead of a lit spot, it projects a spot of darkness.
And instead of discharging its battery, it charges it.
I could really use one of these...
(Score: 2) by GreatAuntAnesthesia on Tuesday January 16 2018, @11:36AM
http://www.rogermwilcox.com/darksucker.html [rogermwilcox.com]
(Score: 2) by TheRaven on Tuesday January 16 2018, @10:54AM (7 children)
sudo mod me up
(Score: 1, Informative) by Anonymous Coward on Tuesday January 16 2018, @03:29PM
Two electrons are repelled by the EM force, everyone is told this, but usually, they ignore that gravity is also pulling them together. Why?
That is because the force of gravity is 4.1*10^42 times smaller than that of the EM attraction.
That is: 4,100,000,000,000,000,000,000,000,000,000,000,000,000,000.
(Score: 2) by JoeMerchant on Tuesday January 16 2018, @09:05PM (5 children)
Fine, so you can build a nucleus out of negative mass particles, then what? These negative mass nuclei are going to scatter.
🌻🌻 [google.com]
(Score: 2) by TheRaven on Wednesday January 17 2018, @10:33AM (4 children)
sudo mod me up
(Score: 2) by JoeMerchant on Wednesday January 17 2018, @01:15PM (3 children)
O.K. now you've made atoms, maybe molecules (wasn't clear to me that the negative mass particles were charged, but... let's say they are)
toss a chunk out in free space, over time it will disintegrate, just like how over time planets form - from the force of gravity.
🌻🌻 [google.com]
(Score: 2) by TheRaven on Wednesday January 17 2018, @01:29PM (2 children)
No it won't. Really. Molecules are held together in large objects by electromagnetic attraction between the nuclei and the free electrons. Do the magnet experiment that I proposed in my original post and you'll see that the electromagnetic attraction from the arrangement of electrons in a few grams of iron is far greater than the gravitational attraction from the entire mass of the Earth. If this were not the case, then any solid object would fall apart as soon as it became close to a planet.
For objects of only a few tons, the gravitational force holding them together is so small in comparison to the EM force that it's going to be smaller than any rounding errors in your calculations or experimental measurement. If you change the sign on that force, you will not observe any difference.
If you still don't believe me, put two small plastic objects on your desk in front of you. They are held in place by electromagnetic force between their surface and the surface of the desk (that's what causes friction), they are attracted to each other by their respective gravitational pulls. Get back to me when they move together.
How did you manage not to learn all of this at school?
sudo mod me up
(Score: 2) by JoeMerchant on Wednesday January 17 2018, @02:19PM
I know the forces, I know they have differing magnitudes and rates of decay at distance, I know they differ in magnitude by many orders...
I also know that: there aren't any negative mass asteroids or planets hanging out around our solar system - at least none that we have observed. There aren't any significant (aka observable) quantities of negative mass particles (or quasi-particles) mixed in with any of the objects we have studied.
In a planet where quantities of uranium sufficient to create a 100kW sustained fission reaction have naturally occurred and left evidence (https://gizmodo.com/there-s-a-naturally-occurring-nuclear-fission-reactor-i-1475445638), I would expect that something like negative mass quasi-particles, if they were inclined to hang together, would have already.
So, perhaps with great care and energy, like that used to magnetically bottle anti-matter or fusion reactions, you might assemble a large object composed with a significant quantity of negative mass quasi-particles. I'd still call that "hard to handle."
🌻🌻 [google.com]
(Score: 2) by Immerman on Wednesday January 17 2018, @02:27PM
However, unless the entire planet has a phenomenal net charge there will be neutral particles present - at which point the attraction of gravity will push them away (unless they had an imaginary gravitational mass, making it a repulsive force)
Of course... it's actually quite likely that such a planet *would* have a ridiculous charge, negative mass protons would clump together, while -m electrons would be repelled. In fact, since you don't need the nuclear force to hold the protons together, you'd end up with essentially a neutron-star density material. And the electrons... they'd probably form an intensely charged black hole... or an "anti-black hole" if their gravitational mass was also negative... I'm not even sure what that would mean.
(Score: 2) by Immerman on Tuesday January 16 2018, @02:58PM
Would they though?
Electrons scatter because they experience bipolar attraction - i.e. opposites attract, while like charges repel.
But gravity is a unipolar force, where like "charges" attract. What exactly negative mass would mean is actually a topic of some serious speculation. Negative gravitational mass would seem to suggest the gravitational force between bodies would still be attractive, though if they have negative inertial mass as well, then that attractive force would indeed drive them apart.
On the other hand - gravitational forces are minuscule compared to the other forces - so if you applied a unipolar electrostatic charge to them then the resulting repulsive force between them would cause them to clump together.
And it's the interaction with normal matter that tends to really break physics - charge up two bodies with opposite inertial mass to generate a strong repulsive force between them, and the normal mass body will perpetually accelerate away from the negative mass body, which will perpetually chase it at the same speed. An infinite energy source in the palm of your hand - which is one of the reasons that real negative inertial mass is generally regarded as unlikley to exist. But hey, sounds like negative mass pseudo-particles may have some useful properties anyway.
(Score: 2, Funny) by aristarchus on Tuesday January 16 2018, @05:28AM (7 children)
Is it just me, or could we not use more positive news aggregation? You know, uplifting stories about the triumph of the human spirit, the victory of intellect over brawn, things about Hugh Manatees, aristarchus submissions! Besides, follow this: "negative mass", "dark matter", "Black Sabbath", "Black Mass"!!! This is what we have let in with the Satanic Temple Fine Article, and we already know about the Dark Rituals being held at CERN, with the Pentangle and the Inverted Cross and the Latin Spoken Backwards!!! So would not a nice, cheery, skeptical and sarcastic submission from aristarchus lighten the mood for us all? Just asking. . .
(Score: 1) by Sulla on Tuesday January 16 2018, @06:57AM (2 children)
No
Ceterum censeo Sinae esse delendam
(Score: 2) by aristarchus on Tuesday January 16 2018, @07:10AM (1 child)
Oh, Sulla! So negative, again? What possible gain for the Republic is there in this? Pax Romana must endure, and for that we require Greek humor, even aristarchus.
(Score: 3, Funny) by FatPhil on Tuesday January 16 2018, @09:18AM
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by jimtheowl on Tuesday January 16 2018, @05:35PM (3 children)
Why is it that you fail to see this? Because of a reaction to certain words to which you react emotionally instead of rationally?
Aristarchus would not approve.
(Score: 2) by aristarchus on Tuesday January 16 2018, @09:16PM (2 children)
The tip-off is the "room-temperature" thing. Smells like "room-temperature cold fusion", only will less nuclear energy. Color me "Skeptical".
(Score: 3, Insightful) by jimtheowl on Tuesday January 16 2018, @09:48PM
Certain apparatus in physic experiments require extremely cold temperatures. It is easier to reproduce an experiment at room temperature, so it actually invites peer review.
I am not saying that their paper is valid and wouldn't be surprised if someone which knows more about the topic knocks it down, but at first glance seems well explained and detailed enough to warrant some reading.
(Score: 2) by Immerman on Wednesday January 17 2018, @02:30PM
Yeah, it's like all that "room temperature chemistry" they keep spouting about. Bunch of nonsense I say - how are you supposed to get chemical reactions without a particle accelerator to smash them together with enough energy to break chemical bonds? :-D
(Score: 3, Interesting) by KritonK on Tuesday January 16 2018, @10:29AM (2 children)
Negative mass also means negative momentum. Thus, a beam of these negative mass particles, striking an object made of ordinary, positive mass, would make it move towards the source of the beam, essentially acting as a tractor beam.
And there I was thinking that Star Trek's tractor beams were even more improbable than warp drive!
(Score: 2) by maxwell demon on Tuesday January 16 2018, @12:53PM (1 child)
The problem with this idea is,of course, that the space between space ships tends to be filled with vacuum, not with monolayer MoSe2. Not to mention that the ships tend to be too far away from each other to form an effective cavity, no matter how shiny they are.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 2) by The Archon V2.0 on Tuesday January 16 2018, @05:24PM
> The problem with this idea is,of course, that the space between space ships tends to be filled with vacuum, not with monolayer MoSe2.
Crazy talk. How can I hear all the explosions then?
(Score: 0) by Anonymous Coward on Wednesday January 17 2018, @12:20PM
I can see it now...
Scotty: "Captain, The entire Magic Dust converter assembly is fused. It's going to blow!"
Captain Kirk: "Scotty, quit snorting the Magic Dust"