Electron spin doesn't exist.
Electron spinning needs superluminal speed.

Contents ↓

• Unreal electron spin can be replaced by orbital motion.
• Quantum mechanical unphysical model stops all science
• No experimental evidence of electron spin
• Spintronics, spin torque, MRAM do Not use spin.
• Spin wave = unreal magnon quasiparticle is useless.
• Nitrogen vacancy (= NV ) center with fake spin is a useless sensor.
• Electron spin qubit is impractical, Not spin.
• Quantum mechanics needs fictional quasiparticle models
• Spin Hall effect does Not use spin-orbit interaction

No experimental evidence of quantum mechanical (unphysical) electron spin whose measurable magnetic field called Bohr magneton (= μ_B ) can be explained by realistic electron's orbit

(Fig.S)  Electron spin is an unreal faster-than-light spinning.

• Electron is Not spinning.
• Electron spin can be replaced by electron's orbit
• Electron spin needs unreal exchange energy lacking exchange force.

Electron spin is unrealistic because a tiny (point-like) electron must be spinning much faster-than-light to generate the observed magnetic moment ( this lower ).

So quantum mechanics paradoxically started to claim this unphysical electron spin is Not actual spinning, though it allegedly has spin angular momentum.

This paradoxical nature of electron spin makes us realize we can explain all the experimental results based on this fictional electron spin by realistic electron's orbital motion.

Because both electron's orbital motion and fictitious spin are said to have the same indistinguishable magnetic field called Bohr magneton (= μ_B = only this magnetic field is measurable ) of Bohr's realistic orbit.  ← Electron spin is unnecessary ( this p.2 ) with No experimental proof.

↑ Unphysical spin's angular momentum-1/2 or g-factor-2 can Not be directly measured (= spin-g-factor=2 has to be guessed from the measured Bohr magneton divided by unmeasurable spin-1/2 angular momentum allegedly caused by Not-real rotation,  this p.4-2-obstacle ).

The unphysical quantum electrodynamics (= QED ) based on fictional virtual particles always gives meaningless infinities (+ artificial cancellation or hocus-pocus renormalization by other infinities ), which can Not predict spin-g-factor or anomalous magnetic moment at all, contrary to hypes.

↑ No evidence of electron spin-1/2.

The unphysical electron spin can be replaced by the realistic electron's orbit.

In addition to the unphysical faster-than-light electron spinning ( this p.2-1.1 ), the electron spin unrealistically can Not be slowed down or accelerated no matter how many times electrons collide or interact with other particles ( this-1st-paragraph,  this 3rd-paragraph,  this 13th-paragraph ).  ← Quantum mechanics provides No reason why the electron spinning speed is Not slowed down or changed.

On the other hand, the realistic electron's orbital motion can naturally explain the constant angular momentum or Bohr magneton based on the experimentally-verified de Broglie wave theory keeping the same angular momentum = an integer × ℏ ( this p.6 ) to avoid destructive interference of de Broglie wave.

As I said, the electron spin lacks reality, and its (measurable) magnetic moment can be replaced by the realistic electron's orbit, so the electron spin is unnecessary.

Atomic fine structure allegedly caused by the paradoxical spin-orbit magnetic energy can be naturally explained by the realistic Bohr-Sommerfeld fine structure without spin ( this 5th-paragraph,  this-lower historical footnote ).

Anomalous Zeeman effect seen in alkali atoms such as sodium is too big to explain by the tiny spin-orbit magnetic interaction, so the electron spin disagrees with experimental results.

The energy difference between singlet (= spin up an down ? ) and triplet (= spin up-up, down-down ? ) states is as large as Coulomb electric energy (= 1 ~ 2 eV, this p.3-middle,  this 3s3p singlet ¹p and triplet ³p energy difference is 13140cm-1 = 1.629 eV ), which is far bigger than the tiny spin-orbit or spin-spin magnetic energy (= 0.0001 eV,  this-p.10-left-2nd-paragraph ).  ← electron spin cannot explain singlet-triplet large energy difference.

Pauli exclusion repulsive energy and ferromagnetism are also too strong to explain by the tiny spin-spin magnetic interaction (= electron spin magnetic energy is too weak, and useless ).

Unrealistic electron spin needs the unphysical exchange energy (= lacking exchange force ) for Pauli principle and ferromagnetism, which hampers science.

So quantum mechanics had to introduce the unphysical concept called exchange energy ( this p.17-19,  this p.11-12 ) lacking exchange force ( this p.9-upper ) to explain these Pauli principle, ferromagnetism, singlet-triplet energy levels, whose energies are far bigger than the original spin-spin magnetic energy.

This unphysical exchange energy needs antisymmetric wavefunctions where all electrons in different orbitals and different atoms must be magically exchanged (= so each electron must unrealistically exist in all different atoms in this antisymmetric exchange wavefunction ).

All quantum mechanical Schrödinger equations for multi-electron atoms are unsolvable, so physicists have to artificially choose fake trial wavefunctions or basis sets with freely adjustable parameters as (fake) atomic unsolvable solutions, which cannot predict any physical values, and quantum mechanics is useless.

This Schrödinger equation is not only unsolvable, unable to predict any physical values, but also too time-consuming to calculate the energies of the chosen (fake) antisymmetric wavefunctions that must exchange all electrons' orbitals ( this p.2-3, p.5 ), and calculate all combinations of exchange energies.

No evidence of electron spin. Spin exchange energy cannot be predicted by quantum mechanics.

So quantum mechanics has to rely on the ad-hoc rough approximation treating all different electrons as one-pseudo-electron or fictional quasiparticle model with fake (effective) mass in the current mainstream density functional theory (= DFT or Kohn-Sham theory, this p.3-5 ).

This one-pseudo-electron DFT must artificially choose (fake) exchange-correlation energy functional (= including the unphysical exchange energy ) and pseudo-potential, which cannot predict any values, so the unphysical exchange energy (= related to electron spin ) is an artificial concept irrelevant to quantum mechanical prediction (= DFT is Not ab-initio but just empirical, this 7~9th-paragraphs,  this p.23 ).

↑ So the electron spin is also artificial, Not the result of quantum mechanical prediction (= No evidence of electron spin ).

In these antisymmetric wavefunctions and one-pseudo-electron DFT approximation, each electron must unrealistically exist in all different atoms and orbitals (= single electron is unrealistically shared by all atoms ) by the unphysical exchange interaction, which prevents each atom from having definite shape and boundary.

As a result, quantum mechanical unphysical exchange energy lacking exchange force hampers scientific development by preventing researchers from using real atomic models with experimentally-measurable shapes and boundaries.

This unphysical quantum mechanical exchange energy lacking exchange force is said to be caused by (fictitious) kinetic energy change ( this p.9-10 ) due to de Broglie wave (= Schrodinger wavefunction is also based on de Broglie wave theory ) interference in antisymmetric wavefunction.

↑ We should stop using these unrealistic quantum mechanical exchange energy (= linked to unrealistic electron spin ), quasiparticle, one-pseudo-electron DFT to develop useful nanotechnology based on real atomic model with actual shapes and real Pauli repulsive force based on real de Broglie wave.

Quantum mechanics can only describe the observed physical phenomena by relying on fictitious quasiparticle model with unreal effective mass, or one-pseuco-electron DFT, which unphysical model prevents progress of all applied science.

(Fig.Q)  If we start to use the experimentally-obtained real atomic model with actual shapes, quantum mechanical unphysical model is unnecessary, which is feared by academia, journals.

Quantum mechanics, which cannot utilize real atomic model with actual shapes, hampers science.

The important point is that (useless) quantum mechanics is unable to describe physical phenomena of materials and molecules by using real particles or concepts, which fatal defects of quantum mechanics cause the current deadend mainstream science.

All the media's misleadingly-colorful pictures are completely inconsistent with the present mainstream quantum mechanical unphysical shapeless atomic model.

Quantum mechanics has to rely on fictitious quasiparticle model or unrealistic quasi-electron with fake effective masses ( this p.2,  this p.5-4th-paragraph ) to (meaninglessly) explain electromagnetic properties in metals, semiconductors, insulators, molecules and (misleadingly-overhyped) spintronics.

Unphysical Pauli exchange energy → impractical one-pseudo-electron DFT model is the current mainstream quantum mechanical method.

The paradoxical quantum mechanical Pauli principle requires every electron to unrealistically spread and exist in all different atoms inside materials by the unphysical exchange energy lacking real exchange force.  ← This unphysical exchange energy is related to (unrealistic) electron spin.

This unreasonable Pauli exchange energy is why the current most-widely-used only mainstream quantum mechanical approximation called density functional theory (= DFT ) or Kohn-Sham theory tries to describe the whole materials as one pseudo-electron ( this p.2-3 ) or fictitious quasiparticle model with unrealistically-changeable effective masses and pseudo-spins using artificially-chosen pseudo-potentials or exchange functionals whose universally-exact form is still unknown ( this p.3-5,  this p.6-7,  this 3rd-paragraph ).

All quantum mechanical models such as DFT are not only unable to predict physical phenomena but also hampering development of science.

So quantum mechanical most popular DFT method (= the current only choice for solid or semiconductor physics ) just artificially choosing approximate exchange-energy functionals or pseudo-potentials often giving wrong results is an incorrect theory with No ability to predict any physical values ( this p.7.  this p.4(or.3),p.13(or p.12) ) which means there is No such thing as a correct quantum mechanical prediction, contrary to the media-hype.

↑ Artificially-chosen pseudo-potentials or (fake) basis wavefunctions with freely-adjustable parameters show quantum mechanics is unable to predict any physical phenomena, meaning quantum mechanical methods are just "fake ab-initio" or ad-hoc empirical theory artificially fitted to experimental values ( this p.23-last-paragraph,  this p.3-3rd-paragraph,  this p.3-right,  this p.4-2nd-paragraphs ), and it lacks real particle picture ( this-last-paragraph,  this p.3-2.2 ).

↑ Quantum mechanical wavefunctions and its most widely-used DFT approximation are unable to give real atomic or electron picture with concrete shape or size, which unphysical quantum mechanical models hampers researchers from using real atomic model or shapes as practical parts for building useful nano-devices or treating diseases.

So it is far better to use the experimentally-observed atomic shapes and properties from the beginning than to waste too much time in the meaningless, useless, time-consuming unphysical quantum mechanical model and equations.

Quantum mechanical band theory and widely-used Hubbard spin model lack real physical objects.

Actually, quantum mechanics often relies on unphysical band model (= using one fictitious quasi-electron approximation) that has to be based on wrongly-average pseudo-electron with fake effective mass and fictional crystal quasi-momentum (= or wavenumber k ), energy ( this p.3,  this p.12-14 ).  ← Band model can Not designate the precise positions of electrons due to unrealistically-spreading electron band model (= an actual individual electron must be bound to one atom at a time instead of the unrealistically-spreading band or electron's plain wave picture, this p.12-13 ), so useless.

Quantum mechanics can only express each electron and (fictitious) quasiparticle by using nonphysical math symbols such as creation and annihilation operators ( this p.3,  this p.3,  this p.2-Results, this p.2-Results ) and abstract (useless) 100-year-old equations called Heisenberg or Hubbard spin models where the fictitious (exchange) interaction parameter J, U or t must be artificially adjusted ( this p.5-6,  this p.12,  this p.4,  this p.2-right ) with No realistic, consistent theoretical basis ( this p.3-last-paragraph ).

↑ The fact that the current mainstream atomic theory or quantum mechanics is unable to describe physical phenomena by real particles with real physical shapes and masses means scientists in all fields are unable to use real atomic or molecular models with real shapes and sizes as parts for designing and building useful molecular nano-machines for curing diseases.

This is why all the current applied science such as biology, medicine and manufacturing industry is deadend, as shown in still-incurable cancers, still-impractical hyped quantum computers, impractical green-new technology, already-dead Moore's law (= this is true, though many companies that want subsidy tend to refuse to admit it ) in semiconductor industry..

If researchers start to use real atomic shapes to develop useful science, today's quantum mechanical useless unphysical model becomes unnecessary, which inconvenient fact is suppressed by academia, journals spreading overhyped science news.

Due to the unphysical mainstream physics, researchers in all fields are wasting their time only in aiming to publish papers in journals instead of aiming to invent really useful machines or cure diseases.

These unphysical impractical concepts intended only for publishing papers in journals are the main reason why even old-fashioned archaic universities can skyrocket their tuition limitlessly by suppressing real scientific progress in all industries.

If researchers start to use the experimentally-observed actual atomic shapes and properties to develop useful technology, the current quantum mechanical unphysical impractical (quasiparticle) model and equations are unnecessary and forgotten.

↑ Academia and journals fear that researchers stop using the unphysical (useless) quantum mechanical model that just wastes their time, so they need to spread overhyped (pseudo-)science news almost everyday to suppress this inconvenient fact.

Examples of quantum mechanics treating actual material using fictional useless pseudo-models.

The 6th and 10th paragraphs of this science news about the alleged research offering insights into the metal-to-insulator transition say

"Quantitative determination of the interaction parameters in the Schrodinger's equation of real materials has been a very difficult task.. (= quantum mechanical Schrodinger equation has been useless for any multi-electron materials )"

"However, when the materials are quasi-one-dimensional (= Not real model ), the atomic lattice often violently fluctuates.."

↑ They ( this p.8-9, Fig.9, p.12-left ) tried to explain this mechanism using fictional quasiparticle models such as exciton and phonon, expressing those particles by nonphysical math operators with No realistic shapes and one-pseudo-electron DFT model with empirically-chosen exchange functional and many freely-adjustable parameters artificially fitted to experimental results.  ← No quantum mechanical prediction, and useless pseudo-models lacking real particle figures or shapes hamper science development .

↑ This p.8-VII-electrons are expressed as nonphysical math operators (= c^† ) with No shapes whose interaction parameters were artificially fitted to experiments,  this-p.9, Fig.9-fictitious phonon, exciton quasiparticles' nonphysical math operators lack real shapes,  this-p.12-left= one-pseudo-electron DFT with semiempirical correction, with No quantum mechanical prediction.  ← useless quantum mechanical pseudo-model.

So the last paragraph of this hyped news just vaguely says
"Once we have their quantum DNAs in hand, these complex materials will (= just about speculative future, still useless now ) be a lot more tameable for predictive materials engineering (?)"

All the current methods allegedly measuring electron spin such as ESR, Kerr effect, spin Hall effect, spin-ARPES can be explained by electron's orbital motion.  Unreal electron spin is unnecessary.

(Fig.E)  Unrealistic electron (faster-than-light) spinning is unnecessary to explain any experiments which just detect electromagnetic field naturally explained by electron's orbital motion.

• Electron spin resonance (= ESR ) is irrelevant to spin
• Magneto-optic Kerr effect (= MOKE ) is irrelevant to spin
• Inverse spin Hall effect is irrelevant to spin
• Spin-ARPES is irrelevant to spin

Electron spin resonance (= ESR ) just detects magnetic field equal to Bohr magneton (= μ_B ) that can be naturally explained by electron's orbital motion without (unreal) electron spin.

In fact, No experiments allegedly measuring electron spin can prove the existence of electron spin.
The electron spin is just an imaginary thing (= Physicists officially declare that an electron is Not actually spinning ).

Electron spin (magnetic) resonance (= ESR ) or electron paramagnetic resonance (= EPR ) is said to be the method of detecting electron spin (= though an electron is Not actually spinning ).
Of course, it is impossible to see the unrealistic electron spin (= if an electron is spinning, it must be the unrealistic faster-than-light spinning ! ) or its angular momentum (= or g-factor ) directly.

ESR energy splitting equals 2 × Bohr magneton (= orbital motion, Not spin ) × magnetic field

In ESR, all researchers can measure is energy level splitting (= through detecting light emitted from or absorbed into atoms ) under applied magnetic field B where the measured energy interval is equal to Bohr magneton (= μ_B ) × the magnetic field B × 2 (= difference between two orbits of upper and down magnetic directions ).

This ESR energy splitting can be naturally explained by the realistic electron's orbital motion whose magnetic moment is equal to Bohr magneton or the electron spin whose (spin) magnetic moment is also Bohr magneton ( this p.2,  this 3rd-paragraph ).

Both the electron's orbit and electron spin are said to have the same Bohr magneton, accidentally, which are indistinguishable.
Because the magnetic moment is equal to g-factor × angular momentum.

Electron's orbital motion's magnetic moment = g-factor (= 1 ) × orbital angular momentum (= 1 ) × Bohr magneton = one Bohr magneton (= μ_B ).

Electron's spin magnetic moment is also  spin-g-factor (= 2 ) × spin angular momentum (= 1/2 ) × Bohr magneton = one Bohr magneton (= μ_B,  this p.3 ).

As a result, ESR can be naturally explained by the realistic electron's orbital motion, and the unrealistic electron spin is unnecessary (= the concept of Bohr magneton originally came from the successful Bohr's atomic orbit without spin ).

Light's polarization changed by material's magnetic field (= Kerr or Faraday effect ) interacting with the light can be explained by electron's orbital motion.  Unreal electron spin is unnecessary.

One of methods for allegedly detecting (fictional) electron's spin magnetic direction is magneto-optic Kerr effect (MOKE) where the polarization of the (classical) light wave reflected from (or penetrating ) the magnetic material changes depending on the material's magnetization, which material's magnetization has nothing to do with electron spin, though ( this p.13-1.1,  this p.2-p.13 ).

Light or electromagnetic wave is known to change its polarization after being reflected by magnetic materials (= Not spin,  this p.13(or p.7) ), depending on the direction of magnetic field (= magnetization or magnetic moment ).  ← This magneto-optical Kerr effect (= MOKE ) or Faraday effect had been already known long before (unrealistic) quantum mechanics was born ( this p.20 ), so electron spin (or quantum photon particle ) is irrelevant to this light reflection.

In Faraday effect, the polarization of (classical) light wave getting through the material changes depending on the material's magnetization parallel or antiparallel to light propagation.  ← the different directions of magnetization means the different directions of the electron's orbital motion that differently affects the right or left-circularly-polarized light.

These Kerr or Faraday effects can be naturally explained by classical electromagnetic wave theory and the realistic electron's orbital motion whose magnetic moment or Bohr magneton (= which modifies the light polarization ) is equal to that of (unreal) electron spin.  ← Both the orbital motion and electron spin with the same Bohr magneton are indistinguishable with respect to magnetization.

Actually, in Kerr effect, only when the material's magnetic field includes the component parallel to the incident electromagnetic light wave's propagating direction (= polar or longitudinal ), this light's (magnetic) phase is modified, and resultantly the light's polarization is changed like linearly → elliptically-polarized light ( this p.3-5,  this p.13-14(or p.7-8),  this Figure 2 ).

↑ This Kerr effect just agrees with classical light wave theory = when the parallel component phase of electromagnetic wave changes, the light polarization (= linear ↔ circular ) is known to change.

It is impossible to improve today's technology by this very weak Kerr effect (= MOKE ) that is useless.

The light polarization change by material's magnetization through this Kerr effect is too tiny to improve or replace today's data storage device (= so this Kerr MOKE effect is used only in impractical experiments )

This p.3-last-paragraph says "Since the MOKE AC signals are typically very weak, great care must be taken "

This p.40(or p.39)-last~p.41(p.40) says
"image with a very low Kerr signal and very dim (dark image). Kerr effect is already too small to be observed, this large amount of light loss will further reduce the Kerr sensitivity of the setup"

↑ As a result, as long as this Kerr effect or MOKE (= whose signal is too weak, and which needs expensive bulky light-generating, detecting devices ) is used in (fictitious spintronics) experiments, it will never lead to developing today's technology.

Inverse spin Hall effect (= ISHE ) just detects faint electric field (= Not spin ) caused by electrons' scattering depending on electron's orbital motion, which is irrelevant to electron spin or paradoxical relativistic spin-orbit interaction.

Another main method of allegedly detecting electron's spin magnetic direction is inverse spin Hall effect (= ISHE ), which has nothing to do with electron spin, contrary to that name.

In the inverse spin Hall effect (= equal to spin Hall effect ), the magnetic current (= caused by electron orbital motion or unreal spin ) is said to be changed into the measurable electric voltage change ( this p.2-Fig.1 ).  ← The unreal electron spin itself is directly undetectable in this method.

↑ Electrons orbiting in different directions are scattered or veer in the different directions (= left or right side ) due to the different friction or collision with the surrounding electrons like classical Magnus effect ( this p.3-2nd-last-paragraph ).  ← A rotating ball veers into left or right direction, depending on the the ball's rotating (= electron's orbiting ) direction that influences the friction against the surrounding air.

↑ So when electrons' current with magnetization in one direction is injected, they tend to be slightly scattered in one direction (= left or right side with respect to the moving direction ), which causes the measurable (faint) electric voltage, which is the true mechanism of the inverse (fake) spin Hall effect or ISHE without spin.

↑ A point-like spinning electron (= Not actual spinning though ) with almost zero size can Not cause this (electric) scattering (= depending on the spinning direction ) due to the friction against the surrounding electrons (= electrons cannot directly touch each other due to Coulomb repulsion ), so it has to rely on paradoxical relativistic spin-orbit magnetic interaction that contradicts the original Einstein relativity, so the electron spin is false.

We cannot measure (fictional) electron's spin magnetic direction by applying external magnetic field as shown in Stern-Gerlach-type experiments

As one of ways to roughly estimate (fictional) electron spin's direction, the current physicists sometimes rely on very unreliable instruments called spin-ARPES (= angle resolved photoemission spectroscopy ) based on measuring the (electric) scattering direction of electrons ejected by (classical) light through photoelectric effect.

The point is it is impossible to measure the direction of the (unrealistic) electron spin itself or spin magnetic direction directly in this spin ARPES or other experiments.

Because if we apply external magnetic field to the unseen electron spin, this spin direction randomly flips (= changes ) in the direction parallel or anti-parallel to the external magnetic field, so the measured spin magnetic direction is not equal to the original unmeasurable spin direction.

In the famous Stern-Gerlach experiment, which just measured the magnetic moment of silver atoms instead of directly measuring the electron spin, the original silver's atom's magnetic moment direction was changed randomly in direction parallel or antiparallel to the external magnetic field.

So they have to rely on other methods (irrelevant to electron spin) of just measuing electrons' scattering direction like in spin-ARPES instead of directly measuring electron spin magnetic moment's direction ( this spin detector at Bloch,  this p.9 ).

This p.6-2. says
"Unfortunately, the concept of a simple Stern–Gerlach type spin separator does Not work for charged particles like electrons."

Spin-ARPES (= angle resolved photoemission spectroscopy ) cannot measure '(fictional) electron spin', either.

So they try to (baselessly) 'guess' the (imaginary) electron's spin direction by vaguely seeing the directions or intensities of electrons scattered by some metals like Au target, which method is called spin-ARPES.

In this Spin-ARPES, they (baselessly) claimed electrons ejected by incident light by photoelectric effect are sent to hit the metal, and get scattered by this metal toward right or left sides depending on the (unseen) electron's spin direction.

↑ So even this spin-ARPES cannot measure the direction of the electron spin itself or spin magnetic moment directly.

First of all, electrons easily change their original (fictitious) spin magnetic directions when they absorb the incident light's energy (= so they cannot know the material's original electron's spin state or direction by this spin-ARPES ), and they are also affected by the material's other electrons' magnetic fields.

And the directions in which electrons are scattered are very uncertain, unpredictable, and easily influenced by the irrelevant multiple Coulomb scattering with other electrons and nuclei (= of course, electrons' orbital directions instead of a point-like fictitious electron spin also infuence this scattering ).

↑ Electrons orbiting in different directions (= instead of the unrealistic spin ) are ejected and flying in slightly-different directions which easily affects the scattering directions or intensities of spin-ARPES result.  ← Electron spin is unnecessary, electron's orbital motion can explain different scattering directions in spin-ARPES.

This p.2-2nd, 4th paragraphs-p.3 say
"we cannot simply use the spin of the electrons as a tag and measure independently the photoelectron spectra for spin-up and spin-down electrons..
In practice, one therefore exploits the spin-dependence in a scattering experiment (= instead of directly measuring spin's magnetic direction ) "

"Does the spin-polarized spectrum (= of spin-ARPES ) reflect the true spin polarization of the electronic states in the system under study ? Unfortunately, this is Not necessarily true
several different mechanisms inherent in the photoemission process are discussed that affect the spin polarization that is experimentally observed"

"All these effects can hamper the characterization of spin-resolved bands in the ground state. They are in most cases not well known (= many unknown factors make spin-ARPES results unreliable )."

Spin-ARPES relies on paradoxical spin-orbit effect or unphysical exchange energy lacking exchange force, so No evidence of electron spin.

A spinning electron (= Not real spinning though ) is a point-like particle with almost no size, so it is impossible for such a point-like electron spin to affect electrons' scattering direction, when electrons hit the metal (= ex. Au target ).

So physicists needed to fabricate some imaginary mechanism of spin-ARPES where the electron spin direction affecting (Coulomb) scattering is said to be based on relativistic spin-orbit effect (= called Mott scattering ) or fictitious exchange interaction (= VLEED scattering, this p.49-52 ) lacking real exchange force ( this-lower-our approach ).

Though quantum mechanical artificial pseudo-model cannot predict this ad-hoc exchange energy or relativistic spin-orbit interaction due to artificially-chosen exchange-energy or pseudo-potential ( this p.10 ).

As shown in this, the relativistic spin-orbit effect is paradoxical and physically impossible, because they say moving electrons do Not experience (fictitious relativistic) magnetic field from the stationary nuclei, and only when seen from the electron's rest frame, the stationary nuclei appear to be moving and causing fictitious relativistic magnetic field that may affect spin-scattering direction through (fictitious) spin-orbit magnetic interaction.

↑ The fact that whether relativistic spin-orbit interaction may happen or not depends on observers' viewpoint (= seen from electron's rest frame or moving frame ) means this relativistic spin-orbit (fictitious) magnetic effect is paradoxical and wrong.

There are many unknown factors, multiple scattering making it impossible to measure electron spin direction by spin-ARPES.

Furthermore, this spin-ARPES based on the fictitious spin-orbit effect (= Mott detector ) has very bad detection efficiency due to multiple uncertain scattering and accelerated electrons easily penetrating target metals without being detected ( this-middle-spin-resolved photoemission spectroscopy ).

This p.5-right-last-paragraph says
"However this effect is weak and cannot be easily resolved at all scattering angles or energies.. At low energy the electron cloud shields the nucleus reducing the Mott effect, and for softer scattering angles the electron is likely to multi-scatter (= this spin-ARPES cannot measure electron spin easily )"

Detection efficiency of spin-ARPES is too bad to believe.

Spin-ARPES based on (fictitious) quantum mechanical exchange energy (= called VLEED ) is said to distinguish the electron spin direction based on the ( unfounded ) assumption that electrons with different spin directions may be reflected by target magnetized metal with slightly-different probabilities  ← the different electrons' scattering direction depends on electron spin direction through exchange interaction ?

But the detection efficiency of this spin-ARPES is also bad, and easily affected by many other irrelevant factors.

The detection efficiency of spin-ARPES is called Sherman function (= S ) which must be artificially and experimentally determined by fitting many free parameters, because different materials with different shapes and thickness, different incident lights, different angles easily change the measured electrons' scattering direction, and undermine the reliability of spin-ARPES or Sherman function ( this p.14-4. ).

The typical Sherman function or spin-ARPES detection efficiency is only about 0.2 ( this p.3-left ) which means spin-ARPES easily misinterprets the electron spin direction with 80% error rate.

This p.1-right says
"the estimation of S_eff (= Sherman function ), however, is Not an easy task
The absolute calibration can be achieved by the usage of spin-polarized electrons,. but the setup of the spin-polarized electron source itself is hard work (= it is impossible to prepare electrons with some desired spin direction, because the applied magnetic field changes the electron spin direction randomly up or down ). "

Spin-ARPES cannot detect (fictitious) electron spins even in ferromagnets due to extremely-bad detection efficiency.

Even when this spin-ARPES was performed against the ferromagnets such as Fe, Co, Ni (= which should ideally show 100% spin polarization ), they often failed to show spin polarization ( this p.13-2nd-paragraph ).

Even in the latest research, the observed magnetic polarization asymmetry against ferromagnet nickel (= Ni ) is only less than 3.0% (= 97% electrons showed random scattering directions irrelevant to spin or magnetic directions,  this-p.16-right-lower-green-line-asymmetry,  this p.1-right obtained only 3.2% polarization asymmetry in magnetized ferromagnet Ni ).

This p.5-(2) showed Sherman function (= S_FEL = non-error rate ) is only 0.1 (= 90% error rate ) and this p.6-Fig.2 says estimated polarization P is about 17% means the observed (fictitious spin) asymmetry is only 17% × 0.1 = 1.7% (= 98.3% of scattered electrons showed random scattering directions irrelevant to spin after absorbing incident light ).

↑ The directions of electrons' scattering are easily affected by positions, various conditions such as incident light and electron's orbital direction (= Not spin ), so this spin-ARPES based on uncertain electrons' scattering to roughly estimate (fictitious) electron's spin direction is very unreliable.

See Spin-torque-transfer (= STT )-MRAM is deadend, irrelevant to spin

See Spin wave or faint magnetic fluctuation is extremely short-lived and useless.

NV center in diamond is an useless quantum sensor

Practical quantum computer will need millions of qubits.  But only 2~6 silicon spin qubits (= each qubit can take only 0 or 1 values ) have been created, which is hopeless, useless.

(Fig.Q)  Spin qubit shows only complicated energy levels in each quantum dot irrelevant to electron spin.

Spin qubit quantum computer tries to use the spin up or down direction of an electron confined in a quantum dot (= called an artificial atom = a small semiconductor consisting of many atoms) by adjustable electromagnetic field as a quantum bit or qubit (= electron spin up = 0, spin down = 1 ).

↑ But an electron is Not actually spinning, so electron spin does Not exist.

Physicists can detect Not the electron spin itself but two energy levels whose interval is 2gμ_BB (= g is g-factor,  μ_B is Bohr magneton,  B is the applied external magnetic field ) interacting with microwave.

↑ If spin qubit really utilized the (fictional) electron spin, this g-factor must be "2".

But actually they can detect more complicated g-factor values completely different from electron spin's g-factor 2.
So there is No evidence of spin qubits using (fictional) electron spins.

The future practical quantum computer is said to require more than millions of qubits ( this 2nd-paragraph,  this 3rd-paragraph,  this 1st-paragraph,  this p.3-1.introduction ).

But the current silicon spin qubits are only several ~ 6 qubits ( = each qubit can take only 0 or 1 values, so just 6 bitstring can Not compute anything.  this p.1-left,  Intel's latest hyped 12-qubit chip only for academic research with No practical use, is just about platform, and Not about building 12 qubits themselves ) which are far from practically-required millions of qubits.

In addition to these impractically small numbers of qubits, the current quantum computers (= still Not computers ) are too error-prone to be useful.

This p.5-Fig.5 shows preparing just 3-qubit GHZ state (= all 3 qubits are 000 or 111 bit states ) caused high error rate of 20~30% (= Fig.5g shows fidelity = 1 - error rate is 71.4 ~ 83.6% ), which is completely useless.

↑ To hide the inconvenient truth that the current quantum mechanical technology has been deadend and unrealistic, a lot of baseless media-hypes about the quantum computer-pseudo-science and fictional electron spin need to be created and spread every day.

Quantum dot spin-qubit uses various g-factors (= ratio of magnetic moment to angular momentum ) completely different from the spin-g-factor of 2, so the spin qubit does not use spin.

The gyromagnetic ratio or g-factor is the ratio of magnetic moment to angular momentum.  Classical electron's orbit's g-factor is 1, and the (fictional) electron spin's g-factor is said to be 2.

↑ This spin-g-factor itself is unmeasurable, and only the magnetic moment called Bohr magneton is measurable, which is the same as the classical electron's orbit, because the spin-angular momentum 1/2 (= 1/2ℏ ) is half of the orbital quantized angular momentum of 1 (= ℏ ).

Quantum dot-spin qubit uses the complicated (effective) magnetic moment or g-factor (= different from spin-g-factor 2 ) combining multiple electrons' orbital motion instead of the fictional spin, so the spin-qubit does Not use electron spin.

This p.2-right-4th-paragraph-ESR spectroscopy in quantum dot spin qubit used g-factor = 0.35, which is different from electron spin g-factor of 2.

This site ↓

p.59-6.1-Qubit uses g-factor = -0.44 (= Not spin g-factor of 2).

p.62-top says "effective (= fake ) g-factor g_eff, which can be larger than the bare (spin) g-factor."

This-p.3-Fig.2h used g-factor = 11.255.
This p.3-last used g factor = 9.28.
This p.1-right-lower used g-factor = -0.4.

↑ None of these g-factors is the electron spin g-factor = 2
So there is No evidence of electron spin in quantum dot can artificially control fake (= effective ) g-factor by applied voltage.

No evidence that spin qubit uses (fictional) electron spin.

Quantum dot electron spin qubit does Not use unphysical (faster-than-light) electron spinning or Pauli exchange repulsion.

Silicon-type spin qubit is said to use the quantum dot's (unrealistic) electron spin up (= 0 ) or down (= 1 ) as each qubit's state.

But it is impossible to observe an unrealistic electron spinning directly.
And their so-called spin-qubit does Not use electron spin, because they used artificial g-factors different from the spin-g-factor of 2.

All they can measure is irrelevant electric current or Coulomb voltage ( this Fig.1c ) instead of electron's spin magnet.

They baselessly claim, when two adjacent quantum dots include two electrons with the same spin up-up or down-down, these two electrons may repel each other by quantum mechanical (fictitious) Pauli principle exchange energy lacking real exchange force, and eventually electric current may be blocked under applied voltage.  ← just imagination

First of all, a quantum dot is an artificial (= Not real ) atom with about 50nm size ( this p.2-Fig.1 ) containing more than 1000 ~ 10000 of atoms that is far bigger than a single atom (= only 0.1 nm ), hence, each quantum dot has large space enough to contain more than two electrons without caring about whether two electrons enter one same smaller atomic orbital exerting Pauli exclusion principle or not.

Actually, in this quantum dot's Pauli blockade mechanism, one electron was artificially fixed by external electric field in the place completely distant from the other electron, and only this other electron could move as electric current through different routes ( this p.3-Fig.1 ), which had nothing to do with Pauli principle repulsion that requires two electrons to enter the same one tiny atomic orbital far smaller than a single quantum dot (= consisting of 10000 atoms ) or a bigger artificial atom.

In the actual quantum dot or artificial atom, much more complicated mechanism happens, and the electric current depends on relationship between electron's orbital motion and other surrounding atoms, which can be artificially-controlled by external (exchange) voltage ( this p.1-right-2nd-paragraph ).  ← Fictional electron spin is completely irrelevant to spin qubit.

Quantum mechanics needs various fictional quasiparticle models with unreal effective masses to explain multi-particle phenomena in metals, semiconductors, insulators, molecules.., which quantum mechanical pseudo-models hinder science.

(Fig.F)  A single electron 'breaks' into two fictional quasiparticles of spinon carrying only spin and holon carrying only charge !?  ← this ridiculous impractical quasiparticle model stops science from advancing

Quantum mechanical Schrödinger equations for multi-electron atoms are unsolvable (= unable to predict atomic energies ), useless and too time-consuming for larger molecules and materials.

So quantum mechanics needs fictitious unreal quasipartice model with fake effective mass and charge ( this 3rd-paragraph ) to approximately explain the multi-particle material's electromagnetic properties such as electric conductance.

These unscientific quantum mechanical quasiparticle models lack real atomic shapes (= these old impractical quasiparticle models have made No progress for about 100 years ), so they clearly prevent the development of science and technology.

This 1st paragraph says
"where the collective behavior of a large number of interacting particles can be described as if they were single particles. These quasiparticles are Not elementary particles"

↑ So these fictional quasiparticle models with fake effective masses (= the current mainstream physical models ) just approximately (and incorrectly) represent the collective behavior of the actual many-atomic material as one pseudo-particles with No real shapes ( this p.2-left,  this p.1-left ) due to the impractical multi-electron Schrödinger equations ( this 3rd-paragraph ).

Quansiparticle is useless, Not a real elementary particle.

This p.2-2nd~3rd paragraphs and p.4-3rd~4th-paragraphs say
"Very often, the Schrodinger equation does not directly provide such an understanding (= quantum mechanical Schrödinger equation is useless )."

"As we cannot generally directly use the Schrodinger equation to understand an interacting system, we have to start from the beginning when we are faced with a many-body system. We have to treat the many-body system as a black box, just as we treat our mysterious and unknown universe (= quantum mechanics is unable to deal with many-atomic materials )."

"But, in the many-body system, the collective excitations are not elementary... Thus, in many-body systems we have collective excitations (also called quasiparticles ) "

"..If we believe that our vacuum can be viewed as a special many-body material, then we have to conclude that there are no elementary particles (= quasiparticles are Not real elementary particles )."

↑ To hide this inconvenient truth of the present deadend science based on unrealistic quantum mechanical quasiparticle models lacking physical shapes (= expressed just as meaningless math operators,  this p.13-last-paragraph,  this p.22 ), the media and academia need to spread overhyped news with misleadingly colorful particle picture (= fictitious quasiparticles can move faster than light !?  this p.11-2nd-paragraph ) that appears to be real.

See this page.

See this page.

See this page.

See this page.

See this page.

See this page.

See this page.

See Spin Hall effect is useless.

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