Physicists Say Graphene Could Create Mass 184
eldavojohn writes "Graphene has gotten a lot of press lately. The Nobel prize-winning, fastest-spinning, nanobubble-enhanced silicon replacement is theorized to have a new, more outlandish property. As reported by Technology Review's Physics Blog, graphene should be able to create mass inside properly formed nanotubes. According to Abdulaziz Alhaidari's calculations, if one were to roll up graphene into a nanotube, this could compactifiy dimensions (from the sheet's two down to the tube's one), and thus 'the massless equations that describe the behavior of electrons and holes will change to include a term for mass. In effect, compactifying dimensions creates mass.' What once would require a massive high-energy particle accelerator can now be tested with carbon, electricity, and wires, according to the recent paper."
A new particle (Score:5, Funny)
Scientists have now isolated the particle that causes this strange mass inducing effect, and have dubbed it the "YoMamma".
This phenomenon closely related to: (Score:4, Insightful)
The bogon [hacker-dictionary.com].
Seriously, can't anyone at Tech Review spot the flaw here? A tube still has more than one dimension. Even if you managed to create a chain of single carbon atoms, you'd still have multiple dimensions, in that the atoms comprising the chain are not infinitely short and infinitely flat.
Bah. Sensationalist nonsense non-news.
Re:This phenomenon closely related to: (Score:4, Informative)
Yes, but tech blog made a hash of it. (Score:4, Insightful)
Cheers, thanks. The main issue is that the blog really made a hash of the explanation with sensationalist claptrap:
... which is utter hokum. Further down the page, there are a couple breakdowns of the paper itself, which make it clear that what they're doing is what you say -- constraining the physics of a potential experiment to simplify the mathematics involved.
Cheers,
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A tube still has more than one dimension
And here I was hoping for graphene mobius strips becoming anti-gravity generators to allow their existence.
Shucks.
Re:This phenomenon closely related to: (Score:4, Funny)
Time to start stapling bacon to cats.
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Re:A new particle (Score:4, Funny)
You just Bushified the conversationalism.
It's called our circle of science! (Score:2)
What once would require a massive high-energy particle accelerator can now be tested with carbon, electricity, and wires, according to the recent paper."
Out of the garage, into the lab, back to the garage. Bill Nye must be so proud :)
Re:It's called our circle of science! (Score:5, Informative)
The link to the paper just gives the executive summary, which actually conveys little information. Even wikipedia wasn't much help. If there's a physicist out there, I get the impression that somehow leptons are being converted to fermions? If so, how, and why do they? If not, could someone give a good explanation?
This is fascinating, but I can't find much explanation.
http://www.ncbi.nlm.nih.gov/pubmed/17358966 [nih.gov]
Magnetic confinement of massless Dirac fermions in graphene.
De Martino A, Dell'Anna L, Egger R.
Institut für Theoretische Physik, Heinrich-Heine-Universität, D-40225 Düsseldorf, Germany.
Abstract
Because of Klein tunneling, electrostatic potentials are unable to confine Dirac electrons. We show that it is possible to confine massless Dirac fermions in a monolayer graphene sheet by inhomogeneous magnetic fields. This allows one to design mesoscopic structures in graphene by magnetic barriers, e.g., quantum dots or quantum point contacts.
PMID: 17358966 [PubMed]
Re:It's called our circle of science! (Score:5, Funny)
If there's a physicist out there, I get the impression that somehow leptons are being converted to fermions?
When life hands you leptons, make leptonaide.
Indeed, I'm not a physicist. How'd you guess?
Re:It's called our circle of science! (Score:4, Funny)
Indeed, I'm not a physicist. How'd you guess?
Um, your user name?
Re:It's called our circle of science! (Score:5, Informative)
Actually, the abstract nails what the actual news here is.
You can't confine a Dirac electron electrostatically. They show that it can be done with magnetic fields. This is sort of cool because it has potential ramifications for incorporating nanotechnology into electronics.
After the wharrgarbl, it mutates into a headline about creating mass and using it to power FTL starships from video games.
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AWESOME!! I pick the ship from Mass Effect, for obvious reasons.
Something Fishy (Score:5, Informative)
If there's a physicist out there, I get the impression that somehow leptons are being converted to fermions?
Leptons (e..g electron) are fermions. However there is something very fishy with this paper. For example 10^6 m/s is not relativistic. If you calculate the gamma factor (gamma=1 is what Newtonian physics assumes) you get 1.0000056. This means they are very non-relativistic and Schrodinger should work fine for them unless there is some subtle effect at play. Indeed to give electrons this energy you need to accelerate them through a potential of 2.8 volts so rather than needed a particle accelerator any one with a vacuum pump, a vacuum-tight container, some wire and two AA batteries can experience the fun of "relativistic" electrons.
What I suspect is happening is that the conditions on graphene have altered the electron behaviour so, rather than test anything fundamental, you are testing the properties of electrons on graphene. You cannot do real relativistic physics with this because if you get an unexpected result you have no idea whether it is because there is some new, unexpected physics at work or whether your approximation of the environment is simply wrong and you need to use a different model for it. Hence, while interesting, this is not the way to do real, relativistic physics: for that you need something that is truly relativistic, not just something which might, under certain conditions, act like something relativistic.
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I get the impression that somehow leptons are being converted to fermions?
I'm not a physicist, but it is my understanding that leptons are fermions. The two main groups are fermions (take up space, more or less) and bosons (don't take up space). Fermions further break down into two groups, hadrons (quarks) and leptons (electrons, muons, tauons, and neutrinos).
Can anybody summarize TFA? (Score:2)
Re:Can anybody summarize TFA? (Score:5, Funny)
I think they're just claiming the mass they expect to make next year, assuming they'll balance their mass sheets at that point?
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Yep. It's a math trick at this point. What's interesting is that even having a mass term in the equations implies that we COULD create mass, if we supply the proper conditions (like adding lots of energy at one end of the tube).
Or at least, that's my guess. TFA is an abstract that I'm barely understanding, and the linked paper is way over my head.
Re:Can anybody summarize TFA? (Score:5, Informative)
All science predictions are math tricks. If the prediction holds up, our existing models are correct, otherwise, our existing models are broken. Creating mass from graphene is not a new theory, it is the _consequence_ of our existing theories that someone cleverly derived.
Point is, either way, Abdulaziz Alhaidari is now famous and has done the incredible. He's either famous for making a marvelous derivation of our existing theories, or he's famous for disproving our current models by explaining what our current models predict that would later be experimentally contradicted. Just as the Manhattan project was a test of atomic theory; if it worked, an amazing weapon was created; if it didn't work, it had profound ramifications on invalidating the the atomic theory of the day. Either it's a win for engineering, building something amazing, or a win for science, changing the models to more closely match reality.
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Or he will become famous like Fleischmann and Pons [wikipedia.org].
Just sayin.....
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Or
[X] He's a blithering crackpot.
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"Just as the Manhattan project was a test of atomic theory; if it worked, an amazing weapon was created; if it didn't work, it had profound ramifications on invalidating the the atomic theory of the day."
That's an insane interpretation of the Manhattan Project... How in the world did you arrive at that conclusion?
He read XKCD today.
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Established since decades? Um, you do realize that neutrons were discovered only in 1932. The discovery of fission was in 1938. The Manhattan project began in 1942. The Nobel Prize for the discovery of nuclear fission was awarded in 1944 for Hahn's discovery in 1938.
Theories need to be experimentally tested; if theories were never tested, we'd still have the theory that heavier objects fall faster than lighter objects, that the world is flat, that Newtonian mechanics explains planetary orbits, etc. Th
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Create mass via lots of energy.
Like
E=mc^2
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No, more like a Catholic priest. They create mass from hot air, holy water, some wine and a cracker, don't they?
Physics can't do that!
Your lithp ith thowing (Score:2)
Itth not a math trick, itth a *mathth* trick.
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the best awnser I could come with is : We dont know yet:
There are some important mathematical differences between the mass that can be generated this way and the stuff you can rap your knuckles on. But now physicists have the chance to compare the effects in an ordinary lab.
Re:Can anybody summarize TFA? (Score:5, Informative)
The /. title of this article is wrong, stupid and misleading.
The title of TFA is "Dynamical mass generation via space compactification in graphene", which is mostly incomprehensible.
The abstract sez "Fermions in a graphene sheet behave like massless particles. We show that by folding the sheet into a tube they acquire non-zero effective mass as they move along the tube axis. That is, changing the space topology of graphene from 2D to 1D (space compactification) changes the 2D massless problem into an effective massive 1D problem."
A plain english annotated translation is "Electrons in a graphene sheet behave like massless particles. We show that by folding the sheet into a tube they behave like massive particles as they move along the tube axis. That is, changing the shape of graphene from 2D to 1D changes the 2D massless problem into an effective 1D massive problem, which may be easier to solve or model or understand in certain respects.
Note electrons have the same real mass in both cases. Mass is not being created or destroyed.
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kdawson posted it, but I wonder if that's his fault or eldavojohn's.
edj, I know you read regularly, so what do you have to say?
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People (i.e., mostly you) seem to blame kdawson, but really, he's just clicking the button when the post bubbles to the top of the Firehose, which happens because the Firehose is an idiocracy. People voting there are mostly ignorant, so anything that is above their understanding gets a positive nod, because most things that reach the front page are above their understanding, so they think that's the criterion.
Sometimes, not voting is better for you than voting is. Like, when you're too uninformed or misin
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It's only incomprehensible ifm yuo don't know what compactification is.
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Is it related to strategery, refudiation, and misunderestimating?
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No, “compactification” is actually a word, albeit an uncommonly used word... “compactify” and “compactifying”, on the other hand, are not (“compact” and “compacting” are the words that the summary writer should have used).
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Is it related to stiction, fahnestock, or spurtle?
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The /. title of this article is wrong, stupid and misleading.
Seconded. Just to clarify, the only thing that's changing here is the dispersion relationship. In graphene the energy of carriers grows linearly with momentum due to strong spin-orbit coupling. In most materials the energy grows proportional to the momentum squared. People have known for a long time that you can do all sorts of things to graphene to change the dispersion relationship so that it acts like other materials. For a bit of a overview see http://www.lbl.gov/publicinfo/newscenter/pr/2008/ALS-g [lbl.gov]
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Electrons in a graphene sheet behave like massless particles
Minor nit: it ain't electrons that behave this way, but quasi-particles resulting from the interaction of free electrons with the substrate. The equations of motion describe the quasi-particle dynamics, not the bare electron dynamics.
But otherwise, yeah. What you said.
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So what you're saying is that he's saying that when you make nanotubes fom graphene you take away some of the magic that making the graphene gave you.
That makes a lot more sense.
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Now, I wonder what would happen when putting electrons in a C60 buckyball...
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Now, I wonder what would happen when putting electrons in a C60 buckyball...
Two electrons enter, one electron leaves...
Who runs Bartertown?!
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It almost sounds like you're saying that sometimes they're a wave and sometimes they're a particle.
Re:Can anybody summarize TFA? (Score:4, Interesting)
It seems to me that it's poorly worded. As far as I can tell, it's not 'creating mass' so much as it is 'creating dependency on mass'
Normally the equations governing movement of electrons are independent of mass. In graphene it appears we should be able to make it dependent on the mass of the electron.
So I believe the article is saying that they believe they can make some particles that didn't appear to have a mass have a new equation for movement that reveals a mass for them. The article mentions that there's a theory that these particles didn't have a mass before this point; that the actual changing of rules that govern movement creates the mass.
I like to think of it as the equivalent of creating charge. You're not actually making anything; you're just moving electrons/protons so they're out of balance. Essentially this could be the same thing with gravity.
Now if this could be reversed to make something mass-less, that would be interesting
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That sounds right.
TL;DR - the electrons (that always have mass) will act like it in this tube thingy, instead of the normal acting like they don't have mass.
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Normally the equations governing movement of electrons are independent of mass.
That's only because the mass of the electron (1/1900th the mass of a neutron or proton) is usually negligible in the dynamics you're calculating.
In superconductors, the equations really do eliminate the force of mass*acceleration from consideration, along with any other forces the electrons would normally be expected to react to (that would contribute to transfer of energy that would make the nuclei vibrate randomly in place; i.e., resistance heating).
Apparently all that's happening here is that he's predic
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Re:Can anybody summarize TFA? (Score:5, Informative)
In graphene, electrons behave like massless particles traveling near the speed of light.
No, electrons do not.
"Charge carriers", which in the case of graphene are quasi-particles that result from the interaction of electrons with the more-or-less 2D medium, do.
The difference is tremendously important, althought admitedly your explaination is about a million times better than the gibberish in the headline and summary.
This is interesting and legitmate physics: charge-carrying quasi-particles in 2D graphene behave as massless particles in a 2+1D spacetime (according to the paper, at least.) If you role the sheet up the dynamics of the quasi-particles becomes that of massive particles in a 1+1D spacetime. This allows experimental realization of systems described by relativistic dynamics (the Dirac Equation) under much simpler circumstances than one might generally expect.
This is similar to the research on "solid state monopoles" which behave like Dirac monopoles over large distance scales. They allow the study of a wide range of phenomena that are otherwise inaccessible (and in the case of Dirac monopoles, entirely theoretical!)
No mass in the ordinary sense of the term is created in the situation the paper describes. If you weighted the system with a sufficiently sensitive balance you would not find that the apparatus weighted more when the graphene sheet was rolled up.
Re:Can anybody summarize TFA? (Score:5, Informative)
Recall that this method of mass generation has been utilized exclusively in high energy physics, supergravity, string theory and related fields [9]. To the best of our knowledge, the present work constitutes the first successful application of this method in condensed matter physics. Another example of space compactification is found in a system consisting of a stack of graphene sheets with coupling between the layers making the massless 3D problem equivalent to an effective massive 2D problem [8].
In other words: "We applied an existing math trick to a new area of theoretical physics, and things look good so far."
You take that, feed it to the "Technology Review" blog, and you get:
The amazing properties of graphene now include the ability to create mass, according to a new prediction.
...which is not quite the same.
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I asked a similar question, and this guy seems to have nailed it. [slashdot.org] I hope the mods notice his answer.
Compactify? Yes, it's a real word. Sigh. (Score:2)
I said, "No way!", but mathematics said, "All your English are belong to us." [wikipedia.org]
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But then again why bother with logic or the truth when we can blame the people without any money for the behavior of the banking industry and Wall Street.
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I’m still trying to figure out why “compaction” isn’t the correct word, other than some physicist bastardized the word and it caught on.
And for what it’s worth, although “compactification” seems to be a word (it’s in the Merriam Webster Unabridged), compactify and compactifying are not.
We call it (Score:5, Funny)
the Mass Effect.
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Artificial gravity? (Score:2)
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I was thinking this too, but it appears as usual that the summary is wrong and that this is just a way of reimagining a problem to better do calculations. No gravity guns/starships to see here, move along.. :(
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Not 1-dimensional (Score:2)
Re:Not 1-dimensional (Score:5, Informative)
Re:Not 1-dimensional (Score:5, Insightful)
Re:Not 1-dimensional (Score:4, Funny)
And if you squeeze the nanotube very, very hard, it disappears!
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no, it turns into diamond
didn't you see superman iii?
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And if you squeeze the nanotube very, very hard, it disappears!
Unless you use it to fashion a container for nanotoothpaste. In which case, no matter how hard you squeeze it, there will always be a little bit left.
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please, no pedantry about how the electron's movement is not truly 1D or 2D, as it exists in a cloud that allows for some freedom of movement in all directions
Since graphene is one atom think, maybe it really is constrained to one dimention? How many electrons can you fit in an atomic width tube, especially considering that all the electrons are repelling each other?
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IANAPP (i am not a particle physicist), but...
an atom is more than 99% empty space, and the electron is so unbelievably small compared to the overall size of the atom (think .0001%), that even given a sheet only one atom thick, the electron still has a lot of free reign to move around, and could be said to be moving in 3 dimensions.
but when discussing the net motion of the electron, this is ignored, we are only interested in when it jumps from one atom to another, thus its movement is best defined as 2D or
Importance (Score:2)
This is either total crap or Nobel Prize material. I'm not qualified to say which. Who's endorsing this paper?
Another Word Please? (Score:2)
Okay Then... (Score:2)
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Unbiggening? Ensmalling? Belittling?
;)
It is pseudo mass, like pseudo force. (Score:5, Interesting)
Of course you know that centrifugal force is not a real force, but a pseudo force you conjure up if you are working on a reference frame attached to the train. From an inertial frame of reference, your velocity is being changed constantly. Change in velocity is acceleration. The change in direction would be towards the center of the circular track. That acceleration is centripetal acceleration. The train is exerting a force centripetal force on you. The reaction from your body on to the train for that force times friction coefficient gives you the force that is holding you still stuck like a fly on the wall of a train moving in a circular track.
As one who has spent years hanging on to the window bars of trains and buses in Chennai, India, let me tell you, no matter how many Einsteins tell you that is a pseudo force, it felt real and that I am still living, not having been run over decades ago by the next bus or train proves that centrifugal force is real. Not pseudo.
Similarly the fermions seem to be having a mass to satisfy some equation in some frame of reference after some coordinate transformation. But really it is not creating any mass.
Somebody mod this up for a clear explanation (Score:2)
This is the first really useful explanation of the mechanism at work in what the paper authors are trying to describe. If only theoretical physicists and tech blog writers were so lucid in their writing.
Cheers,
small question (Score:2)
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What you are feeling is you hitting the side of the train as you were flying through the air.
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It seems to me that all forces, if properly understood, are in some sense pseudo forces.
Two Words: (Score:2)
Meaning of life (Score:2)
What is more, considering the color of the coal, maybe we finally found that predicted "dark matter" that could had done that effect.
Alchemy? Sign me up! Where do I pay? (Score:2)
I'm on my way to a cold fusion seminar given by Professor Ponzi. Please respond ASAP.
Warp Drive (Score:2)
please, be accurate with dimentsions (Score:2)
According to Abdulaziz Alhaidari's calculations, if one were to roll up graphene into a nanotube, this could compactify dimensions (from the sheet's two down to the tube's one),...
The sentence above conveys a wrong impression that tube is one dimensional. Dimensionality of a tube is still the same as of the plane and it is still two. What is different is its topology. Tube has one one dimension with a topology of a line (infinite in both directions) and another one which is a circle and is compact. And it,
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There's something perverse about such an anti-Christian kingdom doing any research involving mass, especially mass construction. If it were the other way around, unrolling the nanotubes into graphene and destroying mass, it would make more sense.
Re:Analogy is not identity! (Score:4, Funny)
Sheldon?
Dr. Sheldon Cooper?
Is that you?
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"With all due respects, Dr. Cooper, are you on crack?" -- George Smoot
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Darn.
I was going to wear that shirt today, too...
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last time I looked, tubes had 2 dimensions... diameter and length...
No, that would be 3 dimensions. Diameter is really 2 dimensions, implying that the shape is circular within those 2 dimensions. Add in length, and you get 3 dimensions. However, the article is not talking about 1 dimensional tubes. It's talking about the 1 dimension in which the particles will move, since the tube is 1 atom thick.
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The only explanation of your wrongness I'm going to provide is:
dimensions != measurements
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We have that already. They're called baristas.
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Sorry, but I don't think you're going to be able to construct a replicator with this.
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He's not a Muslim, you dumbass. Anyone can extrapolate from his name that he's clearly Japanese.
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Sounds like Abdul Alhazred to me. There is clearly a Chthulu connection there.
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The LHC, now available in pocket format!
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Re:Well... (Score:4, Interesting)
I don't think they're suggesting more carbon atoms are being created out of thin air. It seems like they're saying it would have the same size and number of particles, but its mass would go up -- i.e. it would have more inertia. Lots of models in physics require "gaining mass" -- i.e. gaining inertia.
Einstein predicts as you accelerate to the speed of light, you gain mass in your reference frame -- i.e. it becomes harder and harder to accelerate yourself further because you appear to be getting infinitely massive. Einstein is not suggesting that your belly expands and you start generating more particles. He's using "mass" interchangeably with "inertia". Greater mass == greater inertia, when all else is kept constant.
Similarly, the experiment with graphene suggests that a proper configuration of it will yield something with greater inertia (i.e. greater mass) than its constituent masses imply.
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Our laws of physics are supposedly only local to our area of space.
http://arxiv.org/abs/1008.3907 [arxiv.org]