Apr 6, 2019 06:31 PM
Physicists Stuffed a Ghostly 'Skyrmion' Full of 'Antiskyrmions'
https://www.space.com/skyrmion-bags.html
EXCERPT: There are ghostly shapes hidden in magnetic fields. They're not made of stuff in the way a lightning bolt or a beam of light is. [...] But magnetic fields contain things called skyrmions that are different from electrons and photons; a skyrmion is a knot of magnetic field lines looping around each other. As it drifts from one spot to the next, a skyrmion makes itself anew out of the magnetic field lines that are already there. The knot holds together because magnetic field lines resist passing through one another. So, while skyrmions are insubstantial and different from objects we're used to thinking about, they act like more tangible things. Physicists call these skyrmions "quasiparticles," and suspect they could explain phenomena as disparate as ball lightning and the nuclear structure of an atom.
Now, in a new paper, researchers showed that skyrmions can be stuffed inside one another, taking on a completely new shape. These puffed-up "skyrmion bags" are fascinating objects in their own right, but the bizarre things might also be useful for futuristic computing, the researchers said. The team revealed the [...] result relies on a key similarity between the ghostly quasiparticles and solid matter: the existence of antiparticles. Just like protons have counterpart antiprotons that annihilate each other on contact with each other, skyrmions have antiskyrmions. [...] Typically, physicists think of skyrmions as things that exist in magnetic fields. But the particles can also exist in other substances, like the liquid crystals — aligned, rigid, rod-like molecules — that fill the screens on your laptop and some cellphones... (MORE - details)
Fine-Tuning Really Is A Problem In Physics
https://www.forbes.com/sites/startswitha...5ec13d2b80
EXCERPT: . . . When we're faced with a puzzle like this, we have two options for how we proceed. The first is to state that this fine-tuning is simply a result of the initial conditions that are needed to give us the result we have today. After all, there are many coincidences that we observe today where two things appear closely related because they were set up, long ago, with the right conditions that would lead them to appear related today. [...] But this is both an unappealing and an unenlightening path to take, because it assumes that there isn't an underlying cause that gave rise to the effect we observe. The alternative option is to assume that there was some mechanism that gave rise to the apparent fine-tuning we see today.
For example, if you take a look at an enormous rock balanced precariously on a perch, you would assume that something caused it to be that way. It could be because someone carefully placed and balanced it there, or it could be because erosion and weathering happened in such a way that this structure evolved naturally. Fine-tuning doesn't need to imply a fine-tuner, but rather that there was a physical mechanism underlying why something appears finely-tuned today. The effect may look like an unlikely coincidence, but this may not be the case if there's a cause responsible for the effect we see.
[...] The whole point of a fine-tuning argument isn't to declare that we have a weird coincidence, and therefore anything that explains this coincidence is likely to be right. Rather, it points us to the various ways we might think about an otherwise unexplained puzzle, to try and provide a physical explanation for a phenomenon that has no obvious cause. In science, our goal is to describe everything we observe or measure in the Universe through natural, physical explanations alone. When we see what appears to be a cosmic coincidence, we owe it to ourselves to examine every possible physical cause of that coincidence, as one of them might lead to the next great breakthrough. That doesn't mean you should credit (or blame) a particular theory or idea without further evidence, but the possible solutions we can theorize do tell us where it might be smart to look.
As always, we have strict requirements for any such theory to be accepted, which includes reproducing all the successes of the previous leading theory, explaining these new puzzles, and also making new predictions about observable, measurable quantities that we can test. Until a new idea succeeds on all three fronts, it's only speculation. But that speculation is still incredibly valuable. If we don't engage in it, we've already given up on discovering new fundamental truths about our reality. (MORE - details)
https://www.space.com/skyrmion-bags.html
EXCERPT: There are ghostly shapes hidden in magnetic fields. They're not made of stuff in the way a lightning bolt or a beam of light is. [...] But magnetic fields contain things called skyrmions that are different from electrons and photons; a skyrmion is a knot of magnetic field lines looping around each other. As it drifts from one spot to the next, a skyrmion makes itself anew out of the magnetic field lines that are already there. The knot holds together because magnetic field lines resist passing through one another. So, while skyrmions are insubstantial and different from objects we're used to thinking about, they act like more tangible things. Physicists call these skyrmions "quasiparticles," and suspect they could explain phenomena as disparate as ball lightning and the nuclear structure of an atom.
Now, in a new paper, researchers showed that skyrmions can be stuffed inside one another, taking on a completely new shape. These puffed-up "skyrmion bags" are fascinating objects in their own right, but the bizarre things might also be useful for futuristic computing, the researchers said. The team revealed the [...] result relies on a key similarity between the ghostly quasiparticles and solid matter: the existence of antiparticles. Just like protons have counterpart antiprotons that annihilate each other on contact with each other, skyrmions have antiskyrmions. [...] Typically, physicists think of skyrmions as things that exist in magnetic fields. But the particles can also exist in other substances, like the liquid crystals — aligned, rigid, rod-like molecules — that fill the screens on your laptop and some cellphones... (MORE - details)
Fine-Tuning Really Is A Problem In Physics
https://www.forbes.com/sites/startswitha...5ec13d2b80
EXCERPT: . . . When we're faced with a puzzle like this, we have two options for how we proceed. The first is to state that this fine-tuning is simply a result of the initial conditions that are needed to give us the result we have today. After all, there are many coincidences that we observe today where two things appear closely related because they were set up, long ago, with the right conditions that would lead them to appear related today. [...] But this is both an unappealing and an unenlightening path to take, because it assumes that there isn't an underlying cause that gave rise to the effect we observe. The alternative option is to assume that there was some mechanism that gave rise to the apparent fine-tuning we see today.
For example, if you take a look at an enormous rock balanced precariously on a perch, you would assume that something caused it to be that way. It could be because someone carefully placed and balanced it there, or it could be because erosion and weathering happened in such a way that this structure evolved naturally. Fine-tuning doesn't need to imply a fine-tuner, but rather that there was a physical mechanism underlying why something appears finely-tuned today. The effect may look like an unlikely coincidence, but this may not be the case if there's a cause responsible for the effect we see.
[...] The whole point of a fine-tuning argument isn't to declare that we have a weird coincidence, and therefore anything that explains this coincidence is likely to be right. Rather, it points us to the various ways we might think about an otherwise unexplained puzzle, to try and provide a physical explanation for a phenomenon that has no obvious cause. In science, our goal is to describe everything we observe or measure in the Universe through natural, physical explanations alone. When we see what appears to be a cosmic coincidence, we owe it to ourselves to examine every possible physical cause of that coincidence, as one of them might lead to the next great breakthrough. That doesn't mean you should credit (or blame) a particular theory or idea without further evidence, but the possible solutions we can theorize do tell us where it might be smart to look.
As always, we have strict requirements for any such theory to be accepted, which includes reproducing all the successes of the previous leading theory, explaining these new puzzles, and also making new predictions about observable, measurable quantities that we can test. Until a new idea succeeds on all three fronts, it's only speculation. But that speculation is still incredibly valuable. If we don't engage in it, we've already given up on discovering new fundamental truths about our reality. (MORE - details)