Quantum phase estimation (= QPE ) and quantum computing are useless.

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Quantum computers cannot calculate energy
Vatiational quantum eigensolver (= VQE ) is useless

In useless quantum phase estimation (= QPE ), physicists have to calculate (fake) atomic energy (= H ) from artificially-chosen fake trial wavefunction by classical computers with No quantum mechanical prediction nor quantum computation.

(Fig.1)  Quantum mechanics and quantum computers are useless, unable to predict atomic energy.

Quantum mechanics cannot predict energy.

For unsolvable Schrodinger equations that cannot predict any multi-electron atomic energies, physicists have to choose fake trial wavefunctions.

Quantum phase estimation (= QPE ) is said to estimate atomic energy by quantum computing (= actually classical computers disguised as hybrid-quantum computers are used ), which is untrue.

In this quantum phase estimation, physicists have to choose fake trial wavefunctions (= ψ = basis set functions ) close to ground-state energy in advance for unsolvable Schrödinger equations that cannot predict any multi-electron atomic energies.

This-p.7-2.2 says  -- Choose fake wavefunction
"The choice of these basis functions has a critical impact on both the accuracy and the computational cost of electronic structure calculations"

This-p.4-right-II says  -- Artificial choice, No prediction
"the first step of this algorithm is to prepare the system register in a state having good overlap with the ground state of the Hamiltonian H."

Classical computers are necessary

Instead of useless quantum computers, classical computers have to calculate all atomic energy from chosen (fake) trial wavefunctions.

Then, they use classical computers to calculate atomic total energy (= Hamiltonian H ) instead of today's error-prone useless quantum computers. That's all.

↑ Quantum mechanics is useless, unable to predict any multi-electron atomic energies due to the unsolvable Schrödinger equation.

Quantum computers are also useless, too error-prone to calculate anything.

Physicists have to artificially change the atomic energy (= H ) calculated by classical computers into very simple impractical Hamiltonian energy for very small numbers of qubits of today's impractical quantum computers.

Quantum phase estimation (= QPE ) is meaningless

Quantum phase estimation just evolves qubits, whose states are artificially chosen, by some phase expressed by atomic energy (= H ) calculated by classical computers in advance with No quantum computation.

After the artificially-chosen fake trial wavefunction (= ψ ) is changed into very simple version expressed by the quantum computer's qubits, they evolve the wavefunction by some qubit phase operators expressed as U =e^-Ht (= atomic energy H must be computed by classical computers in advance,  this-p.9-Fig.5 ), which is called time evolution ( this-p.2 ).

Then, they measure the resultant qubits' state to estimate the phase (= containing Hamiltonian H atomic energy ) that must be already known in advance by classical computers ( this-p.14,  this-middle-0.-4.   this-p.7 ).

↑ So this quantum phase estimation (= QPE ) and quantum computers are meaningless concepts for calculating atomic energies.

↑ Only classical computers and artificially-chosen fake trial wavefunctions determine the final atomic energy (= H or phase ).

Quantum computers, mechanics are useless.

Just artificially-chosen fake trial wavefunctions and classical computer energy calculations give the resultant atomic energy with No quantum computation nor quantum mechanical prediction in QPE.

This-paper on quantum phase estimation ↓

p.5-2nd~3rd-paragraphs says  -- Classical computer needed
"IPEA (= iterative phase estimation algorithm ).."
"For our proof-of-principle demonstration, all necessary molecular integrals are evaluated classically (= classical computers ) using the Hartree- Fock procedure"

p.6-B. says  -- Classical computers calculate energy
"Restricted Hartree-Fock calculations were carried out on a classical computer using the STO3G basis. The software used was the PyQuante quantum chemistry package version 1.6. The molecular integrals from the Hartree-Fock procedure are used to evaluate the matrix elements of the Hamiltonians H"

p.11-1st-paragraph says  -- Just classical, No quantum
"the four single-electron spin-orbitals (i.e. |0 = occupied, |1 = unoccupied)."
" The ground state energies of the approximate unitary propagators were obtained via direct diagonalization on a classical computer"

This-abstract, p.3-right-2nd-paragraph says
"Quantum phse estimation (= QPE)"
"orbital. h_pq and h_pqrs (of total Hamiltonian energy H of evolution operator of e^Ht in Fig.1, (7) ) are one- and two-electron integrals and they are computed on classical computers prior to quantum simulations"

This-p.2-left-4th-paragraph says
"After obtaining Hsim through this (typically) efficient classical computation, we perform the quantum simulation of this molecule on a single-NV register, which consists of an electronic spin-1 and an associated 14N nuclear spin-1 forming a qutrit pair (= only two useless qubits 01 were used in this research-p.8-Figure 2, which is Not a quantum computer )... iterative phase estimation algorithm (IPEA)"

↑ So instead of useless quantum computers, ordinary classical computers need to be used to calculate (fake) atomic energy from artificially chosen fake trial wavefunctions in this QPE, which quantum mechanical methods cannot predict anything.

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