limits – Harmonia Philosophica

Light speed. Less than 1000 m/s.

Researchers at TU Wien were the first to successfully detect Weyl particles in strongly correlated electron systems – that is, materials where the electrons have a strong interaction with each other. In materials like this, the Weyl particles move extremely slowly, despite having no mass.

“The strong interactions in such materials usually lead, via the so-called Kondo effect, to particles behaving as if they had an extremely large mass”, explains Sami Dzsaber. “So it was astonishing for us to detect Weyl fermions with a mass of zero in this particular type of material”. According to the laws of relativity, free massless particles must always spread at light speed. This is, however, not the case in solid states: “Even though our Weyl fermions have no mass, their speed is extremely low,” says Bühler-Paschen. The solid state lends them its own fixed ‘light speed’ to a certain extent. This is lower than 1000 m/s, i.e. only around three millionth of the speed of light in a vacuum. “As such, they are even slower than phonons, the analogue to the water wave in the solid state, and this makes them detectable in our experiment”. (1)

Low speeds. High speeds.

What is the difference?

The light is fast. But not for light.

Weyl particles are slow. But not for Weyl particles.

The limits you imagine are not there.

Imagine a Weyl particle.

Fast as 10 m/s…

Massless particles. Heavy particles.

High speed particles. Low speed particles.

Depending on the environmental interactions.

Remove them and see.

Everything is fast. Everything is slow…

Imagine a Weyl particle. Fast as light…

In the beginning everything was still and fast as light at the same time. Until we came. And started observing… The cosmos was once still and, thus, fast like lightning. Then the cosmos started moving. And everything came to a halt.

Note: Weyl particles are not particles which can move on their own (like electrons or protons), they only exist as ‘quasiparticles’ within a solid material. “Quasiparticles are not particles in the conventional sense, but rather excitations of a system consisting of many interacting particles”, explains Prof. Silke Bühler-Paschen from the Institute of Solid State Physics at TU Wien. In some sense, they are similar to a wave in water. The wave is not a water molecule, rather it is based on the movement of many molecules. When the wave moves forward, this does not mean that the particles in the water are moving at that speed. It is not the water molecules themselves, but their excitation in wave form that spreads. After physician Paul Dirac had arrived at his Dirac equation in 1928, which can be used to describe the behavior of relativistic electrons, Hermann Weyl found a particular solution for this equation – namely for particles with zero mass, or ‘Weyl fermions’. The neutrino was originally thought to be such a massless Weyl particle, until it was discovered that it does indeed have mass. The mysterious Weyl fermions were, in fact, detected for the first time in 2015.

Getting lost. Barriers. Finding your way home…

If you’re ever lost in Los Angeles, just head for the ocean to get your bearings. This advice works because running into the coast — or any other border — can reset an errant internal GPS system, a new study in mice suggests.

The results help explain how the brain maintains a high-fidelity map of the environment. Specialized brain cells called grid cells signal when an animal reaches certain locales — a discovery that garnered a Nobel Prize in 2014 (SN Online, 10/6/14). Boundaries help course-correct these cells when they go off track, researchers report April 16 in Neuron.

In the experiment, electrodes implanted in the brain monitored the behavior of grid cells as mice moved around in an expansive enclosure. As the mice traveled, grid cells began to throw off the animals’ internal maps by signaling at the wrong places. But encounters with walls set these off-course grid cells right, Kiah Hardcastle of Stanford University and colleagues found. (1)

It is the boundaries which determine the whole.

Only when we reach the limit can we know.

But the limit is never reached. We can only imagine we reach for it. We can only dream of getting there. What we know is that we will never know. Trapped into ignorance, we must choose to trust our inner instinct.

An instinct which tells us that we know. That we are somehow already at that boundary. (We imagine God as the perfect being. Could He be that boundary?) That we had been there once. And that we will be there again if we wish so…

Search for the limits of your thought.

Name them whatever you like.

It is there where your true existence comes from…

Zero.

Nothing.

Everything.

Light. Right. Left.

How can a beam of light tell the difference between left and right? Tiny particles have now been coupled to a glass fiber. The particles emit light into the fiber in such a way that it does not travel in both directions, as one would expect. Instead, the light can be directed either to the left or to the right. This has become possible by employing a remarkable physical effect – the spin-orbit coupling of light. This new kind of optical switch has the potential to revolutionize nanophotonics. (1)

Left.
Right.
Up.
Down.

Name things.
And you will start discovering “impossibilities”.

Stop naming things.
And just everything is possible.

We have limited our selves.
To get free all we have to do is turn right. And left. And up. And down.
Be everywhere. And nowhere at the same time. And just let the light go wherever it wishes to go…

Breaking barriers…

Viewed through microscopes similar to Hooke’s, most cells are see-through and colorless; it’s hard to discern fine features. Due to diffraction, the bending of light, objects smaller than about 250 nanometers — the size of the smallest bacteria — are fuzzy when viewed through an optical microscope, if they can be seen at all. (Consider that most proteins are merely a few nanometers across.) This diffraction barrier, explicitly defined by German physicist Ernst Abbe in 1873, makes a smeared blur of much that happens in and on a cell.

That’s all changed in the last few decades. Scientists have developed a suite of new optical techniques that circumvent the diffraction barrier and show us a cell’s full guts and glory. With new fluorescent tags that light up structures in the dense darkness inside a cell these new optical approaches produce detailed images of what was once invisible. In the pages that follow, some of the most striking images are highlighted, all from animal cells that scientists use to understand basic cellular processes and disease. (1)

Breaking the diffraction barrier.
Breaking the sound barrier.
Breaking the speed of light barrier.

Oups!

No, that cannot be broken.

Or can it?

We have a tendency of “discovering” barriers.
And then we like to “discover” that they are not barriers at all…

Why not accept the world as a whole?
Without barriers.
Just us.
Alone.
Doing whatever we like.
No “laws”. No “limits”. No “barriers”.
Once upon a time we were more powerful than the stars.
Now we look down at the Earth as if we are small small ants…