Friday, 14 July 2017

Psychosocial mechanisms of spin behavior

In previous texts you met spins as joyous arrows for dance pleasure. It is time, however, get to know them closer - what are their needs, motives, schemes of behavior? What are they headed for? Only proper understanding of their psyche will allow us to cooperate with them.

Barbara Kędzierska - Wooden spins
At the beginning, we can split the spins for the place of residence. In materials such as wood, plastic or even most metals, there is real Sodom and Gomorrah. They live there very selfish spins, which, left to themselves, do what they want, including coupling. This is not a very optimistic picture of the degenerate nature of spin.

Why is it so bad? Among other things, it is because spins communicate with one another through a magnetic field. Physicists also call it a dipole-dipole interaction ensuring no one else can understand. Unfortunately, this language is very poor and it is not enough for the spins to get along.

Because we are not a correctional facility, we only deal with decent spins, those living for example in iron or nickel*, and there is hope that some of them will grow up. The straight spins stand upright and - as we know - they can dance. They owe this skill to a good educator. This inner tutor in his own language has effectively taught the spins that in order to live in peace and harmony, one should be empathetic, to help and to share things if someone else needs it. Hence, physicists call this tutor exchange interaction.

Exchange interaction constantly keeps spins from forgetting about good manners and it strives to make their inner selfishness does not interfere. The problem occurs when the area of ​​residence is limited. Spins are exposed to external contacts, which can be especially dangerous if there is some plastic in the area. The material boundaries reduce the morale of the spins and cause them to cease to support each other through dipole-dipole interaction. Even help of exchange interaction may be insufficient. There are two ways to deal with this problem, both commonly used at the same time. First of all, if spins are set parallel to the border, they do not see well what is outside, so the threat is minimized. The other way is to divide the material into domains between which the spins are set in different directions. Since each domain represents other interests, spins watch over their neighbors abroad so that they do not lead up the garden path. This requires a bit of guidance from educators due to the need to introduce appropriate boundary conditions. However, we see clear signs of the emergence of civil society and the development of international co-operation through simple dipole-dipole interactions.

There are also more detailed rules governing the social life of spins. We can determine them by modifying the environment in which they live and their surroundings. This sometimes causes the formation of interesting spin structures such as skyrmions or vortexes. To see how spins dance in such a position, it would be interesting, wouldn't it?

How spins dance in the skyrmion you can read HERE

*Frankly speaking, even in these materials, decent spins are the elite, but always something.

Monday, 8 May 2017

Dancing with the spins

Paweł is a PhD student in our team. He performs aggressive simulations in MuMax. I don’t know details of this program yet, but I have the impression that it is possible to calculate the whole world in it. At least that is how you can conclude from the results that Paweł publishes.

I could not fully understand what the source of this success was. Is it a matter of hard work and talent for processing large numbers? It seemed to me too easy. And I was right. Several weeks ago I discovered what really stands behind this.

I have long been afraid to publicize these facts. This is a very controversial move, but I feel that the world must also know what lies beneath science. What do physicists do in their offices? Scientific discoveries and the process of knowledge creation look very nice on paper, but how is it? It turns out that totally different.

On October 20th, 2016, while sitting in the office of the Department of Physics, I got my third coffee and went to the neighboring room where Paweł and Justyna worked. Knocking on the door I opened and I was surprised when I found them both at the entrance to the vacilala con vuelta.

For a long time I could not understand what was going on. Also Paweł and Justyna were not prepared for such a situation. Losing their steps and knitting their hands, they did something like adios por arriba and sat down on chairs. Only the next day Paweł explained to me what was going on. They just played electronic spins.

Recently I wrote how the electrons were treated all the way through the 20th century. We hope that these times will finally pass. We try to move from the era of brutal charge into the epoch of graceful dancing with spins. Electrons will not commit themselves to mourning the transmission of important information through these wires inside the computer. They will do it with elegance, using their spin to synchronous dance. Our words, sounds and images will be recorded in their steps.

More about Paweł's antenna you can read HERE
The first element is to teach the electrons how to do it correctly. Electron spins dance on their own, but it's more like a Saturday night's fun in the country than the serious dance we're talking about. Usually, they should be brought up to order with a magnetic field. Once they are standing, you can start dictating their tempo by rhythmically changing the external field. Spin dance starts.

We can tell all spins to step at the same time, or to do it with adequate delay in subsequent places like the Mexican wave at the stadium. And it would be best if they could be controlled so that only a selected part of them danced and the rest rested. Why bother the whole company.

This is exactly what Paweł designed. With the help of a special antenna we give rhythm to a short order of spins, and these invite to dance other spins. But not those standing on the sides, but those standing in line. Such a beam like from a laser. The rest need not do anything, it saves energy.

Paweł claims that this was an experiment by analogy. Rather unsuccessful, because it is difficult to simulate a beam in a two-spin system. Even our whole group could not be enough for such a simulation.

Of course Paweł's methods have been discussed in the faculty for a month. We got a new room to fill. Professor Krawczyk thinks that Rueda de Casino needs a better floor.

Thursday, 27 April 2017

The essence of the electronic being

In the old days, the lyrics were written on paper. I do not know how to hold it, wrist hurts from this unbearably. We needed a plastic or metal device with colored fluid. The trunk was pressed against the sheet of paper and the fluid flowed out and moved in the right direction creating letters. To this day people are being tortured with this outdated invention in offices.

Earlier there were horses or mills. In the mill the water hits the wheel, causing it to move. Someone who invented it should get a Nobel Prize, because all the work was done by water. Not like when baking cakes when you have to beat the eggs by hand. 

To not beat in the dark, you could sit by candlelight or at an oil lamp. I do not know if anyone  by that time appreciated such a romantic atmosphere, but it certainly was disappearing immediately when the candles rolled over.

Fortunately, you do not need to do it too often now. Nowadays, all these things electrons make for us, and handmills are limited to giving commands to small particles by pressing the appropriate buttons. Electrons (which - as with Jesus - no one knows exactly what they look like and are everywhere, even in bed) are quite easy to pacify.

I will give you a brief overview of the life of such electrons that work for us. As you may have guessed from the introduction, their career paths may vary, although working conditions may be heavy. Electrons sign a contract at the power plant and it is unclear whether they know what they are up to. At the start of the service, the electrons are thrown into the narrow channel where they are so stiff that they can not stand mentally and they give  a strong kick everyone in front of them. Ultimately, the one who is at the outlet of the channel has no one to kick and the energy of his kick is flagitiously used to drive the drum of the washing machine.

If you think it's inhumane, think of those electrons rattled mercilessly by the thin tungsten wire in the bulb. This pain can only be compared to rubbing any part of the body with the concrete being pulled by the car. Maybe their fate has improved a little lately with other types of light sources, although the moral aspects of these solutions have not yet been analyzed. If you know anything more about it, write me!

Finally, let's go back to this unfortunate writing. You just look at the electrons trapped in tight cages. They sit there obediently inside the computer, for your enjoyment of writing letters. Wrist pain, shame on you!

What is an electron spin
and how does it behave
you will see HERE
while about magnonics
you can read HERE
As you can see, thPauli exclusion principle is just one problem of electrons from a whole range of mischiefs that they encounter. That is why many scientific groups, including the Nanomaterials Physics Division at the Adam Mickiewicz University, strive hard to improve the existence of electrons, to relieve them at least partially. One such idea is to shift some of the responsibility to the spins, which are even cheaper workforce... Honestly, I will say that I do not know if the world will be better thanks to that, but if not, then the signals of the oncoming catastrophe you can expect on this site.