Microsoft-Quantinuum 56-ion-qubit quantum computers cannot correct errors, much less simulate catalyst.

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(Fig.1)  Quantinuum's just 56 error-prone ion qubits are useless, still Not a quantum computer.

Microsoft error-prone qubits are useless, deadend, unable to simulate catalyst.

The 2nd, 5th paragraphs of this hyped news (9/15/2024) say

"Quantinuum's H2 machine, which now has 56 (ion) qubits... all 12 logical qubits were.. a cat state, or Greenberger-Horne-Zeilinger (GHZ) state... error rate of 0.0011 (= 0.11%, this error rate is still too high to be practical )"

"Microsoft reports an end-to-end hybrid workflow was used,... two logical qubits... to prepare the ground state of the active space of an important catalytic intermediate"

Just 56 ion qubits composing 12 logical qubits (= just 12 bitstring ) is useless, cannot simulate anything.  ← still Not a computer

↑ Just 56 ion qubits composing 12 (logical) qubits (= each logical qubit can take only 0 or 1 bit state ) is useless, far from millions of qubits required for a practical quantum computer ( this 19~20th-paragraph ).

Their (misleading) hybrid computer was just an ordinary classical computer, their error-prone just 2 (logical) qubits (= just 2 bitstring 01 ) can Not simulate catalyst or molecular energies.

↑ Today's useless quantum computers cannot calculate anything.  They just tried to make all 12 qubits 0 or 1 identical state (= 000000000000 or 111111111111 ).  ← Even this very simple qubit manipulation (= without calculation ) called GHZ cat state caused irreparable high error rate.

Microsoft-Quantinuum's qubit error rate was very high = 30.1% from which 30% erroneous results were illegitimately discarded (= ignored ) without error correction.

The true error rate of this Microsoft making just 12 qubits 1 or 0 was much higher = 30.1% (= including postselectively and illegitimately discarded or ignored error qubits ) than the above hyped news.

Today's error-prone quantum computers can Not correct their errors (= their error correction operation itself increases or worsens errors ).

So they illegitimately discarded (= ignored ) 30% erroneous results in a postselective way without error correction ( this 4~5th-paragraphs ), so that the final error rate appeared to be 0.1%

This 11th paragraph says "operations and calculations discarded due to errors that could not be corrected. This is still not low enough to enable the large number of operations needed for useful algorithms ( this 8th-paragraph )"  ← still useless, error-prone qubits.

Even just 4-qubit error correction was impossible (= error rate was 80% ! ).  Quantum computer was officially dead.

↑ This research paper of Microsoft, Quantinuum ↓

p.1-right-last-paragraph says "two faults may bring the system to an uncorrectable state. When an uncorrectable state is detected, our fault-tolerance procedure rejects (= discard ) the trial. This “postselection (= cheating, this 6th-paragraph )” means that more trials are needed.. The acceptance rates in our experiments are at least 50%"  ← about 50% results were discarded due to errors, so this research's actual error rates were about 50%, which was too bad, hopeless.

p.11-left-last-paragraph says "This is why we ran the four-qubit error correction experiment on H2. Early experiments with five rounds of error correction on 12 logical qubits.. have shown a potentially problematically high error rate 2%"  ← Error correction of just 12 qubits was impossible in this research.

p.11-Fig.13-(b) shows just 50 rounds of error correction operations on just 4 (logical) qubits (= just 4 useless bitstring,  p.8-Table-III) increased the error rate (= logical error probability ) to more than 1%, even after they illegitimately discarded 80% of all results due to errors (= acceptance probability was only 0.2 or 20% ) without error correction.

↑ So actual error rates of just 4 qubits increased to more than 80% after 50 rounds of error correction (= error-worsening ) operations were conducted !

As a result, contrary to an incredible amount of hypes, today's quantum computers are useless, hopeless, their error-correction is impossible forever.

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