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Index Photos Hacks/ Wotsap Overslack maildird verifygpgmail jcbt jcfilesize typesetpy zeno.qcl brainfuck.xslt Noid Patches Cryptography	zeno.qcl QCL (Quantum Computation Language) is a programming language for quantum computers, including a quantum computer simulator while we wait for the real quantum computers. zeno.qcl is a small program written in QCL that demonstrates the quantum zeno effect. Download zeno.qcl version 0.9 (sig) Measurements can be done in 3 ways: 0 Don't measure at all 1 Measure the normal way 2 Measure in accordance with the Church of the Larger Hilbert Space The qubit is initialized to \|0> and is rotated in nrsteps steps, with pi/steps radians each. Without measurement, it should be rotated to \|1>. Variant 3 will of course take longer time to run since QCL needs to calculate the entagled state with the environment instead of just randomly choosing one environment state, but on the plus side the final dump shows the probability for qubit flipping, which will decrease if nrsteps is increased. Examples: Rotate from \|0> to \|1> in 10 steps qcl zeno.qcl -x 'zeno(0, 10)' Do the same thing but perform a measurement between each step qcl zeno.qcl -x 'zeno(1, 10)' Do the same thing and keep track of the measuring environment qcl zeno.qcl -x 'zeno(2, 10)' Example output with three rotations and Larger Hilbert Space option: $ qcl -f b zeno.qcl -x 'zeno(2, 3)' QCL Quantum Computation Language (64 qubits, seed 4711) : STATE: 4 / 64 qubits allocated, 60 / 64 qubits free 1 \|0000> : Step 0 Fanned out internal state to environment. : STATE: 4 / 64 qubits allocated, 60 / 64 qubits free 1 \|0000> : SPECTRUM q: <0> 1 \|0> : Rotating 1.0472 radians. : STATE: 4 / 64 qubits allocated, 60 / 64 qubits free 0.86603 \|0000> - 0.5 \|0001> : Step 1 Fanned out internal state to environment. : STATE: 4 / 64 qubits allocated, 60 / 64 qubits free 0.86603 \|0000> - 0.5 \|0101> : SPECTRUM q: <0> 0.75 \|0>, 0.25 \|1> : Rotating 1.0472 radians. : STATE: 4 / 64 qubits allocated, 60 / 64 qubits free 0.75 \|0000> - 0.43301 \|0001> - 0.25 \|0100> - 0.43301 \|0101> : Step 2 Fanned out internal state to environment. : STATE: 4 / 64 qubits allocated, 60 / 64 qubits free 0.75 \|0000> - 0.25 \|0100> - 0.43301 \|1001> - 0.43301 \|1101> : SPECTRUM q: <0> 0.625 \|0>, 0.375 \|1> : Rotating 1.0472 radians. : SPECTRUM q: <0> 0.5625 \|0>, 0.4375 \|1> : Final state: 0 : SPECTRUM q: <0> 1 \|0> $
Jörgen Cederlöf <jc@lysator.liu.se>

Jörgen Cederlöf's web pages

zeno.qcl

QCL (Quantum Computation Language) is a programming language for quantum computers, including a quantum computer simulator while we wait for the real quantum computers. zeno.qcl is a small program written in QCL that demonstrates the quantum zeno effect.

Download

zeno.qcl version 0.9 (sig)

Measurements can be done in 3 ways:

 0 Don't measure at all
 1 Measure the normal way
 2 Measure in accordance with the Church of the Larger Hilbert Space

The qubit is initialized to |0> and is rotated in nrsteps steps, with pi/steps radians each. Without measurement, it should be rotated to |1>.

Variant 3 will of course take longer time to run since QCL needs to calculate the entagled state with the environment instead of just randomly choosing one environment state, but on the plus side the final dump shows the probability for qubit flipping, which will decrease if nrsteps is increased.

Examples:

  Rotate from |0> to |1> in 10 steps
    qcl zeno.qcl -x 'zeno(0, 10)'
  Do the same thing but perform a measurement between each step
    qcl zeno.qcl -x 'zeno(1, 10)'
  Do the same thing and keep track of the measuring environment
    qcl zeno.qcl -x 'zeno(2, 10)'

Example output with three rotations and Larger Hilbert Space option:

$ qcl -f b zeno.qcl -x 'zeno(2, 3)'
QCL Quantum Computation Language (64 qubits, seed 4711)
: STATE: 4 / 64 qubits allocated, 60 / 64 qubits free
1 |0000>
: Step 0 Fanned out internal state to environment. 
: STATE: 4 / 64 qubits allocated, 60 / 64 qubits free
1 |0000>
: SPECTRUM q: <0>
1 |0>
: Rotating 1.0472 radians. 
: STATE: 4 / 64 qubits allocated, 60 / 64 qubits free
0.86603 |0000> - 0.5 |0001>
: Step 1 Fanned out internal state to environment. 
: STATE: 4 / 64 qubits allocated, 60 / 64 qubits free
0.86603 |0000> - 0.5 |0101>
: SPECTRUM q: <0>
0.75 |0>, 0.25 |1>
: Rotating 1.0472 radians. 
: STATE: 4 / 64 qubits allocated, 60 / 64 qubits free
0.75 |0000> - 0.43301 |0001> - 0.25 |0100> - 0.43301 |0101>
: Step 2 Fanned out internal state to environment. 
: STATE: 4 / 64 qubits allocated, 60 / 64 qubits free
0.75 |0000> - 0.25 |0100> - 0.43301 |1001> - 0.43301 |1101>
: SPECTRUM q: <0>
0.625 |0>, 0.375 |1>
: Rotating 1.0472 radians. 
: SPECTRUM q: <0>
0.5625 |0>, 0.4375 |1>
: Final state: 0 
: SPECTRUM q: <0>
1 |0>
$

Jörgen Cederlöf <jc@lysator.liu.se>