Протез руки вперше під'єднали до нервів людини (відео)

Вчені під'єднали протез руки до нервів жінки, дозволяючи їй рухати пальцями за допомогою розуму і навіть відчувати тактильні відчуття.

Дослідники з Технологічного університету Чалмерса (Швеція) та біотехнологічної фірми Integrum AB створили протезну руку в рамках європейської дослідницької програми по протезуванню кінцівок DeTOP. Хірурги прикріпили протез до двох кісток передпліччя (променевої та ліктьової) жінки за допомогою титанових імплантатів і під'єднали 16 електродів безпосередньо до її нервів і м'язів, що дозволило їй контролювати руку за допомогою думок і задіяти її, щоб зав'язувати шнурки і набирати текст на клавіатурі.

Це перший клінічно життєздатний і чутливий протез руки, придатний для використання в реальному житті. Про це досягнення повідомляється на офіційному сайті проекту.
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7 Strangest & Coolest Materials Which Actually Exist

Eurovision 2019 / Kate Miller - Zero Gravity - Australia 🇦🇺

https://eurovision.tv/event/tel-aviv-2019

Ask Ethan: How Do Quantum Fields Create Particles?

At the high temperatures achieved in the very young Universe, not only can particles and photons be spontaneously created, given enough energy, but also antiparticles and unstable particles as well, resulting in a primordial particle-and-antiparticle soup. Yet even with these conditions, only a few specific states, or particles, can emerge.BROOKHAVEN NATIONAL LABORATORY

What is our Universe made out of? At a fundamental level, to the best of our knowledge, the answer is simple: particles and fields. The type of matter that makes up humans, Earth, and all the stars, for example, is all composed of the known particles of the Standard Model. Dark matter is theorized to be a particle, while dark energy is theorized to be a field inherent to space itself. But all the particles that exist, at the core of their nature, are just excited quantum fields themselves. What gives them the properties that they have? That's the topic of this week's question, coming to us from Richard Hunt, who wants to know:

"I have a question about Quantum fields. If we model particle properties as excitations of various independent fields (Higgs field for mass, EM field for charge etc) then what causes these excitation waves to travel around together? Is there really some kind of particle entity underlying these waves?"

In other words: what makes a particle have the properties that it does? Let's take a deep look.


The particles and antiparticles of the Standard Model have now all been directly detected, with the last holdout, the Higgs Boson, falling at the LHC earlier this decade. All of these particles can be created at LHC energies, and the masses of the particles lead to fundamental constants that are absolutely necessary to describe them fully. These particles can be well-described by the physics of the quantum field theories underlying the Standard Model, but whether they are fundamental is not yet known.E. SIEGEL / BEYOND THE GALAXY

The particles that we know of have traits that appear to be inherent to them. All particles of the same type — electrons, muons, up quarks, Z-bosons, etc. — are, at some level, indistinguishable from one another. They all have a slew of properties that all other particles of the same type share, including:

- mass,
- electric charge,
- weak hypercharge,
- spin (inherent angular momentum),
- color charge,
- baryon number,
- lepton number,
- lepton family number,

and more. Some particles have a value of zero for many of these quantities; others have non-zero values for almost all of them. But somehow, every particle that exists contains all of these particular, intrinsic properties bound together in a single, stable, "quantum state" we call a particular particle.


The rest masses of the fundamental particles in the Universe determine when and under what conditions they can be created. The more massive a particle is, the less time it can spontaneously be created for in the early Universe. The properties of particles, fields, and spacetime are all required to describe the Universe we inhabit.FIG. 15-04A FROM UNIVERSE-REVIEW.CA

Underlying all of it, there are a variety of fields that exist in the Universe. There's the Higgs field, for example, which is a quantum field that permeates all of space. The Higgs is a relatively simple example of a field, even though the particle that arose from its behavior — the Higgs boson — was the last one ever to be discovered. The electromagnetic (QED) field and color-charge (QCD) field, among others, are also fundamental quantum fields.

Here's how it works: the field exists everywhere in space, even when there are no particles present. The field is quantum in nature, which means it has a lowest-energy state that we call the zero-point energy, whose value may or may not be zero. Across different locations in space and time, the value of the field fluctuates, just like all quantum fields do. The quantum Universe, to the best of our understanding, has rules governing its fundamental indeterminism.


Visualization of a quantum field theory calculation showing virtual particles in the quantum vacuum. Even in empty space, this vacuum energy is non-zero, but without specific boundary conditions, individual particle properties will not be constrained.DEREK LEINWEBER
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Desert Dwellers - Spaces Between

Zero-point energy

Zero-point energy (ZPE) is the difference between the lowest possible energy that a quantum mechanical system may have, and the classical minimum energy of the system. Unlike in classical mechanics, quantum systems constantly fluctuate in their lowest energy state due to the Heisenberg uncertainty principle.
As well as atoms and molecules, the empty space of the vacuum has these properties. According to quantum field theory, the universe can be thought of not as isolated particles but continuous fluctuating fields: matter fields, whose quanta are fermions (i.e. leptons and quarks), and force fields, whose quanta are bosons (e.g. photons and gluons). All these fields have zero-point energy.
These fluctuating zero-point fields lead to a kind of reintroduction of an aether in physics, since some systems can detect the existence of this energy. However this aether cannot be thought of as a physical medium if it is to be Lorentz invariant such that there is no contradiction with Einstein's theory of special relativity.



Liquid helium retains kinetic energy and does not freeze regardless of temperature due to zero-point energy. When cooled below its Lambda point, it exhibits properties of superfluidity.

Physics currently lacks a full theoretical model for understanding zero-point energy; in particular the discrepancy between theorized and observed vacuum energy is a source of major contention. Physicists Richard Feynman and John Wheeler calculated the zero-point radiation of the vacuum to be an order of magnitude greater than nuclear energy, with a single light bulb containing enough energy to boil all the world's oceans.
Yet according to Einstein's theory of general relativity any such energy would gravitate and the experimental evidence from both the expansion of the universe, dark energy and the Casimir effect show any such energy to be exceptionally weak. A popular proposal that attempts to address this issue is to say that the fermion field has a negative zero-point energy while the boson field has positive zero-point energy and thus these energies somehow cancel each other out.
This idea would be true if supersymmetry were an exact symmetry of nature. However, the LHC at CERN has so far found no evidence to support supersymmetry. Moreover, it is known that if supersymmetry is valid at all, it is at most a broken symmetry, only true at very high energies, and no one has been able to show a theory where zero-point cancellations occur in the low energy universe we observe today.
This discrepancy is known as the cosmological constant problem and it is one of the greatest unsolved mysteries in physics. Many physicists believe that "the vacuum holds the key to a full understanding of nature".



In 2014 NASA's Eagleworks Laboratories announced that they had successfully validated the use of a Quantum Vacuum Plasma Thruster which makes use of the Casimir effect for propulsion. In 2016 a scientific paper by the team of NASA scientists passed peer review for the first time. The paper suggests that the zero-point field acts as pilot-wave and that the thrust may be due to particles pushing off the quantum vacuum. While peer review doesn’t guarantee that a finding or observation is valid, it does indicate that independent scientists looked over the experimental setup, results, and interpretation and that they could not find any obvious errors in the methodology and that they found the results reasonable. In the paper, the authors identify and discuss nine potential sources of experimental errors, including rogue air currents, leaky electromagnetic radiation, and magnetic interactions. Not all of them could be completely ruled out, and further peer reviewed experimentation is needed in order to rule these potential errors out.

Kerli - Zero Gravity