So, many of you
have submitted questions on the forum,
and our excellent team has selected the two questions
that received the most votes.
So let me answer these questions.
The first question was
"How does a distributed quantum computer work?"
In particular, does it work similar
than a classical distributed computing system?
And the answer to this is yes.
One way, but not the only way,
to perform a distributed quantum computation
is very similar to what happens classically.
Each node is a quantum processor, and if you
want to perform operations between two qubits,
they have to be moved to the same node
in order to perform a computation.
People are exploring distributed quantum computing,
not just on a large-scale quantum internet,
but specifically as a way to perform
scalable quantum computation at short distances.
Because, if my goal is
to "just" perform a quantum computation,
why put these computing nodes very far apart?
Here at QuTech, we have an effort
where the little quantum computers
are in fact optically connected on one chip,
so the signals between the different quantum
processors need to travel as short as possible.
A computation can then be performed
by moving qubits from one processor to another.
This provides a very nice and scalable path
to build a very large-scale quantum computer,
because we can start with a few
and connect more as we go along.
Now, I've mentioned that
there's two ways of performing a computation
on a distributed quantum processor.
So, the first one was very analogous
to the classical domain.
Every processor can perform a certain set of gate
operations and qubits are moved to that processor.
Another way to perform a distributed quantum
computation is much more quantum and complicated,
where we use a large-scale
quantum error-correcting code
to actually map qubits
to physically two processors at the same time,
in the sense that there's an error-correcting code
that only if I combine the two processors together
they together sort of represent one qubit
or a set of qubits that I want to operate on.
