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Finally! Sub-atomic particle that’s both matter & antimatter observed

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Finally! Sub-atomic particle that’s both matter & antimatter observed — RT News



81cd39ee3b966ac1684051226735592b.jpg

Screenshot from vimeo user Princeton University

Physics, Science, USA

After 80 years of painstaking experimentation, scientists have directly observed a sub-atomic particle that is its own antiparticle. The breakthrough promises a leap forward in quantum computing and potentially shows the path to finding dark matter.

The particles are called the Majorana fermions, after the Italian scientist who proposed their existence back in 1937. Quantum theory was in its infancy at the time, and scientists first theorized that antimatter existed: an opposite particle to the commonly-observed electrons and other particles were necessary for quantum equations to work.

Although since then many forms of antimatter have been observed, the Majorana fermion remained elusive for decades, partially because it virtually doesn't interact with regular particles. A team of researchers at the Delft University of Technology in the Netherlands reported a possible discovery of evidence of the Majorana back in 2012, but other scientists pointed out that their results could have been caused by other phenomena.

Now a team led by Professor Ali Yazdani of Princeton University and his team, which included colleagues from University of Texas-Austin, seem to have pinpointed the particle in an experiment that required months of careful adjustments, a two-story tall microscope floating in an ultralow-vibration lab at the campus and an environment of almost absolute cold. They published the results in the October 2 issue of the journal Science.

The setup was first proposed by Russian-born physicist Aleksey Kitaev, now a professor at the University of California-Santa Barbara, who predicted in 2001 that Majoranas would emerge on the ends of a superconductuve wire under certain magnetic conditions. Given a certain length of the wire, these particles would not annihilate each other due to spatial separation.

The Yazdani team undertook to do exactly that in 2013 after winning a $3 million grant from the Office of Naval Research. They took an ultra-pure crystal of lead, in which atoms naturally align into ridges and placed on one of them a wire of iron, a ferromagnetic material, which was just one atom wide and about three atoms wide. The crystal was then cooled to -272 degrees Celsius, just one degree above absolute zero, to induce superconductivity.

It took almost two years of meticulous work to precisely match the conditions required for the Majorana fermions to emerge, after which the scanning-tunneling microscope was able to detech an electrically neutral signal at the ends of the wire – just as predicted.

"This is the most direct way of looking for the Majorana fermion since it is expected to emerge at the edge of certain materials," Yazdani said. "If you want to find this particle within a material you have to use such a microscope, which allows you to see where it actually is."


The experiment not only confirms that the world indeed works the way quantum physicists thought it did, but has potential for practical applications in quantum computing. A quantum computer operates qubits, basic elements that can represents not only ones and zeroes, but also a quantum state of superposition that is a one and a zero at the same time. The biggest potential field of application of quantum computing is encryption and code breaking.

But quantum superposition states notoriously easily collapse into conventional behavior, so scientists are yet to find the right material to serve as qubits. Stable Majoranas could do the trick (which probably explains why the US military showed such an interest in the research).

“This is more exciting and can actually be practically beneficial,” Yazdani said, “…because it allows scientists to manipulate exotic particles for potential applications, such as quantum computing.”

The team is particularly excited that they could produce Majoranas without the use of any exotic materials.

“We realized that Majoranas could be present even in the common form of magnetism found in iron,"said Allan MacDonald, a physicist who led the Austin team.

The observation of the Majorana fermion has opened the door for other theories as well. Scientists are already seriously considering that neutrinos and anti-neutrinos could be one particle and a kind of a Majorana. The properties and behavior of a neutrino are not dissimilar to that of the Majorana fermiones.

Furthermore, Majoranas are a strong candidate for dark matter – the mysterious substance that comprises most of the universe yet remains elusive because it doesn't interact with regular mater in any way but through gravity.
 
Finally! Sub-atomic particle that’s both matter & antimatter observed — RT News



View attachment 109174
Screenshot from vimeo user Princeton University

Physics, Science, USA

After 80 years of painstaking experimentation, scientists have directly observed a sub-atomic particle that is its own antiparticle. The breakthrough promises a leap forward in quantum computing and potentially shows the path to finding dark matter.

The particles are called the Majorana fermions, after the Italian scientist who proposed their existence back in 1937. Quantum theory was in its infancy at the time, and scientists first theorized that antimatter existed: an opposite particle to the commonly-observed electrons and other particles were necessary for quantum equations to work.

Although since then many forms of antimatter have been observed, the Majorana fermion remained elusive for decades, partially because it virtually doesn't interact with regular particles. A team of researchers at the Delft University of Technology in the Netherlands reported a possible discovery of evidence of the Majorana back in 2012, but other scientists pointed out that their results could have been caused by other phenomena.

Now a team led by Professor Ali Yazdani of Princeton University and his team, which included colleagues from University of Texas-Austin, seem to have pinpointed the particle in an experiment that required months of careful adjustments, a two-story tall microscope floating in an ultralow-vibration lab at the campus and an environment of almost absolute cold. They published the results in the October 2 issue of the journal Science.

The setup was first proposed by Russian-born physicist Aleksey Kitaev, now a professor at the University of California-Santa Barbara, who predicted in 2001 that Majoranas would emerge on the ends of a superconductuve wire under certain magnetic conditions. Given a certain length of the wire, these particles would not annihilate each other due to spatial separation.

The Yazdani team undertook to do exactly that in 2013 after winning a $3 million grant from the Office of Naval Research. They took an ultra-pure crystal of lead, in which atoms naturally align into ridges and placed on one of them a wire of iron, a ferromagnetic material, which was just one atom wide and about three atoms wide. The crystal was then cooled to -272 degrees Celsius, just one degree above absolute zero, to induce superconductivity.

It took almost two years of meticulous work to precisely match the conditions required for the Majorana fermions to emerge, after which the scanning-tunneling microscope was able to detech an electrically neutral signal at the ends of the wire – just as predicted.

"This is the most direct way of looking for the Majorana fermion since it is expected to emerge at the edge of certain materials," Yazdani said. "If you want to find this particle within a material you have to use such a microscope, which allows you to see where it actually is."


The experiment not only confirms that the world indeed works the way quantum physicists thought it did, but has potential for practical applications in quantum computing. A quantum computer operates qubits, basic elements that can represents not only ones and zeroes, but also a quantum state of superposition that is a one and a zero at the same time. The biggest potential field of application of quantum computing is encryption and code breaking.

But quantum superposition states notoriously easily collapse into conventional behavior, so scientists are yet to find the right material to serve as qubits. Stable Majoranas could do the trick (which probably explains why the US military showed such an interest in the research).

“This is more exciting and can actually be practically beneficial,” Yazdani said, “…because it allows scientists to manipulate exotic particles for potential applications, such as quantum computing.”

The team is particularly excited that they could produce Majoranas without the use of any exotic materials.

“We realized that Majoranas could be present even in the common form of magnetism found in iron,"said Allan MacDonald, a physicist who led the Austin team.

The observation of the Majorana fermion has opened the door for other theories as well. Scientists are already seriously considering that neutrinos and anti-neutrinos could be one particle and a kind of a Majorana. The properties and behavior of a neutrino are not dissimilar to that of the Majorana fermiones.

Furthermore, Majoranas are a strong candidate for dark matter – the mysterious substance that comprises most of the universe yet remains elusive because it doesn't interact with regular mater in any way but through gravity.

That's a very big news...and a very important one...other than bosons and fermions( which makes all the particles, particularly matter) ,it was not known that a particle can be its own antiparticle...Wow...Thanks for this news sir..:-)
 
That's a very big news...and a very important one...other than bosons and fermions( which makes all the particles, particularly matter) ,it was not known that a particle can be its own antiparticle...Wow...Thanks for this news sir..:-)

Boson and fermion refer to thermal statistics and wavefunction symmetry under particle exchange (symmetric vs. antisymmetric), not whether it is an anti-particle or not. Both helium 4 and photons are bosons, yet photons are their own anti-particle and helium 4 is not.

Also, this Majorana fermion seems to be a quasiparticlen (a particle formed of the collective motion of other particles in a material - electorn-hole pairs called excitons, surface electron waves called plasmons and quantized lattice vibrations called phonons are all quasiparticles. Anyone with even the most rudimentary training in solid state physics should know this). If it wasn't, it wouldn't need to only occur in single crystal lead. Why is this new, I don't know - I thought Majorana-type fermions were discovered in graphene years ago. Lots of quasi-particles are their own antiparticle. Excitons, for example, annihilate both themselves and each other.

This, IMO, is just basic materials research dressed up as something it is not.
 
Boson and fermion refer to thermal statistics and wavefunction symmetry under particle exchange (symmetric vs. antisymmetric), not whether it is an anti-particle or not. Both helium 4 and photons are bosons, yet photons are their own anti-particle and helium 4 is not.

Also, this Majorana fermion seems to be a quasiparticlen (a particle formed of the collective motion of other particles in a material - electorn-hole pairs called excitons, surface electron waves called plasmons and quantized lattice vibrations called phonons are all quasiparticles. Anyone with even the most rudimentary training in solid state physics should know this). If it wasn't, it wouldn't need to only occur in single crystal lead. Why is this new, I don't know - I thought Majorana-type fermions were discovered in graphene years ago. Lots of quasi-particles are their own antiparticle. Excitons, for example, annihilate both themselves and each other.

This, IMO, is just basic materials research dressed up as something it is not.


Yes!
Boson = Antiparticle.
But Boson do not submit to Pauli exclusion principle, while fermions do.
Now that is the big difference!
 
Boson and fermion refer to thermal statistics and wavefunction symmetry under particle exchange (symmetric vs. antisymmetric), not whether it is an anti-particle or not. Both helium 4 and photons are bosons, yet photons are their own anti-particle and helium 4 is not.

Also, this Majorana fermion seems to be a quasiparticlen (a particle formed of the collective motion of other particles in a material - electorn-hole pairs called excitons, surface electron waves called plasmons and quantized lattice vibrations called phonons are all quasiparticles. Anyone with even the most rudimentary training in solid state physics should know this). If it wasn't, it wouldn't need to only occur in single crystal lead. Why is this new, I don't know - I thought Majorana-type fermions were discovered in graphene years ago. Lots of quasi-particles are their own antiparticle. Excitons, for example, annihilate both themselves and each other.

This, IMO, is just basic materials research dressed up as something it is not.

Thanks Sir...I was not knowing this...Most of these things which you have written are new to me....I only had very very basic knowledge of particle physics...One very important thing that i learned from you is that Helium 4 is a boson...thanks for this knowledge sir...:-)
 
but storing them is an issue since beginning . they can't store them large numbers

A new break through with yet another insurmountable obstacle.




Be warned! This thread is intended for the most optimistic of researchers in the field of science. :rofl:
 
Thanks Sir...I was not knowing this...Most of these things which you have written are new to me....I only had very very basic knowledge of particle physics...One very important thing that i learned from you is that Helium 4 is a boson...thanks for this knowledge sir...:-)

Helium 4 is a boson because its spin is integer. Don't believe me? Electrons, protons and neutrons are all spin half. 2 electrons, 2 protons, 2 neutron = integer spin boson. This is why it can Bose condense at low temperatures into superfluid liquid helium where the Bose condensed He4 atoms share the same momentum state - note that this is impossible for a fermionic system, because sharing the exact same momentum is forbidden by the Pauli exclusion principle.

I'm not a particle physicist by any means, not even close - I'm a materials physicist in semiconductors. Luckily here, their claims were in materials science. Usually, particle physicists don't think of helium 4 as a boson - they think of it as 6 fermions put together. However, in materials science, it is better to look at the sum of the parts.

Yes!
Boson = Antiparticle.
But Boson do not submit to Pauli exclusion principle, while fermions do.
Now that is the big difference!

No, boson does not = antiparticle. A helium 4 atom is not an antiparticle but it is a boson. A photon is a boson and its own antiparticle. On the other hand, positrons are fermionic antiparticles. It is true that only fermions obey the Pauli exclusion principle.

Note that in materials physics, the definition of a particle goes beyond elementary particles - we think of bound or collective motions of electrons in solids as particles. For example, the electron-hole pair produced by photoexcitation of an electron from the valence band to the conduction band in a semiconductor can be called a particle - the exciton. The exciton has a characteristic size, diffusion length, binding energy, etc. and the relative sizes of these compared to the material's sizes affect device properties. For example, excitons in semiconductor nanocrystals are actually larger than the crystal size and this causes very interesting effects such as high brightness photoluminescence.
 
Helium 4 is a boson because its spin is integer. Don't believe me? Electrons, protons and neutrons are all spin half. 2 electrons, 2 protons, 2 neutron = integer spin boson. This is why it can Bose condense at low temperatures into superfluid liquid helium where the Bose condensed He4 atoms share the same momentum state - note that this is impossible for a fermionic system, because sharing the exact same momentum is forbidden by the Pauli exclusion principle.

I'm not a particle physicist by any means, not even close - I'm a materials physicist in semiconductors. Luckily here, their claims were in materials science. Usually, particle physicists don't think of helium 4 as a boson - they think of it as 6 fermions put together. However, in materials science, it is better to look at the sum of the parts.



No, boson does not = antiparticle. A helium 4 atom is not an antiparticle but it is a boson. A photon is a boson and its own antiparticle. On the other hand, positrons are fermionic antiparticles. It is true that only fermions obey the Pauli exclusion principle.

Note that in materials physics, the definition of a particle goes beyond elementary particles - we think of bound or collective motions of electrons in solids as particles. For example, the electron-hole pair produced by photoexcitation of an electron from the valence band to the conduction band in a semiconductor can be called a particle - the exciton. The exciton has a characteristic size, diffusion length, binding energy, etc. and the relative sizes of these compared to the material's sizes affect device properties. For example, excitons in semiconductor nanocrystals are actually larger than the crystal size and this causes very interesting effects such as high brightness photoluminescence.

You are great Sir...:cheers:
 
[quote="FairAndUnbiased, post: 6251484, member: 134981



No, boson does not = antiparticle. A helium 4 atom is not an antiparticle but it is a boson. A photon is a boson and its own antiparticle. On the other hand, positrons are fermionic antiparticles. It is true that only fermions obey the Pauli exclusion principle.

Note that in materials physics, the definition of a particle goes beyond elementary particles - we think of bound or collective motions of electrons in solids as particles. For example, the electron-hole pair produced by photoexcitation of an electron from the valence band to the conduction band in a semiconductor can be called a particle - the exciton. The exciton has a characteristic size, diffusion length, binding energy, etc. and the relative sizes of these compared to the material's sizes affect device properties. For example, excitons in semiconductor nanocrystals are actually larger than the crystal size and this causes very interesting effects such as high brightness photoluminescence.[/quote]
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I should have written "all boson does not mean Antiparticle. Because boson = antiparticle in case of Photons, meson and gluons...

Photoluminescence is caused by photons which are excited. While you are talking of semiconductor luminescence equations, when you started to involve semiconductors nanocrystals (involved in a light emission and used in memory components of hardwares)
 
Actually elementary particles are divided into Baryon, Meson and Lepton. Helium is not an elementary particle.

[quote="FairAndUnbiased, post: 6251484, member: 134981



No, boson does not = antiparticle. A helium 4 atom is not an antiparticle but it is a boson. A photon is a boson and its own antiparticle. On the other hand, positrons are fermionic antiparticles. It is true that only fermions obey the Pauli exclusion principle.

Note that in materials physics, the definition of a particle goes beyond elementary particles - we think of bound or collective motions of electrons in solids as particles. For example, the electron-hole pair produced by photoexcitation of an electron from the valence band to the conduction band in a semiconductor can be called a particle - the exciton. The exciton has a characteristic size, diffusion length, binding energy, etc. and the relative sizes of these compared to the material's sizes affect device properties. For example, excitons in semiconductor nanocrystals are actually larger than the crystal size and this causes very interesting effects such as high brightness photoluminescence.
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Some way you are right. BE statistics can be applied to any system which can be represented by a symmetric wave function. it does not say about the type of system you are considering. it can be a system of elementary particles too.
 
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Some way you are right. BE statistics can be applied to any system which can be represented by a symmetric wave function. it does not say about the type of system you are considering. it can be a system of elementary particles too.

All elementary particles are either bosons or fermions. Give or take a "spin"

In quantum mechanics and particle physics, "spin" is an intrinsic form of angular momentum carried by elementary particles, composite particles (hadrons), and atomic nuclei
 
All elementary particles are either bosons or fermions. Give or take a "spin"
Yep. That is why I said some way you are right. Even a system of particles can be either fermions or bosons too. What I was saying is helium is not an elementary particle. I did not say you are wrong.
 
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