Linked Questions

2 votes
0 answers
19 views

Are classical analogues of quantum computers using superposed waves possible? [duplicate]

The trick of quantum computing is to take the advantage of wave mechanics (superposition) and entanglement. This allows to perform parallel computations/manipulations with $2^n$ superposed waves for $...
Sextus Empiricus's user avatar
27 votes
4 answers
6k views

Are quantum computers just a variant on Analog computers of the 50's & 60's that many have never seen nor used?

In the recent Question "Is Quantum Computing just Pie in the Sky" there are many responses regarding the improvements in quantum capabilities, however all are focussed on the current 'digital' ...
Philip Oakley's user avatar
10 votes
3 answers
790 views

What is the simplest algorithm to demonstrate intuitively quantum speed-up?

What's the simplest algorithm (like Deutsch's algorithm and Grover's Algorithm) for intuitively demonstrating quantum speed-up? And can this algorithm be explained intuitively? Ideally this would be ...
Steven Sagona's user avatar
8 votes
3 answers
2k views

What exactly makes quantum computers faster than classical computers?

What feature of a quantum algorithm makes it better than its classical counterpart? Are quantum computers faster than classical ones in all respects?
Tobias Fritzn's user avatar
16 votes
1 answer
1k views

Is entanglement necessary for quantum computation?

Entanglement is often discussed as being one of the essential components that makes quantum different from classical. But is entanglement really necessary to achieve a speed-up in quantum computation?
DaftWullie's user avatar
  • 52.3k
8 votes
4 answers
1k views

Non-layperson explanation of why a qubit is more useful than a bit?

I have a computer science and mathematics degree and am trying to wrap my head around quantum computing and it just doesn't seem to make sense from the very beginning. I think the problem is the ...
Lee Cascio's user avatar
8 votes
2 answers
586 views

What's the difference between a set of qubits and a capacitor with a subdivided plate?

This is probably just a misunderstanding on my part, but everything I've seen on what quantum computers do thus far seems to suggest that the actual process of reading the entangled qubits would be ...
CoryG's user avatar
  • 197
4 votes
2 answers
733 views

Can classical linear algebra solvers implement quantum algorithms with similar speed-ups?

A quantum algorithm begins with a register of qubits in an initial state, a unitary operator (the algorithm) manipulates the state of those qubits, and then the state of the qubits is read out (or at ...
Jagerber48's user avatar
2 votes
3 answers
441 views

Does each qubit correspond to some wave?

Reading about qubits, I see a lot of names related to waves from physics (amplitude, magnitude, phase, ...). Does it mean that each qubit corresponds to some wave? If yes, what is the mapping between ...
sitems's user avatar
  • 363
2 votes
2 answers
326 views

What is the actual mechanism behind quantum computing?

I was redirected from theoretical computing to quantum computing for this question. I've been mildly researching quantum computers to figure out how entanglement and superposition are utilized for ...
Phil H's user avatar
  • 123
4 votes
1 answer
287 views

Chrononic Computing (Time Evolution Systems)

In a recent question about quantum speed-up @DaftWullie says: My research, for example, is very much about "how do we design Hamiltonians $H$ so that their time evolution $e^{-iHt_0}$ creates ...
user820789's user avatar
  • 3,272
3 votes
1 answer
43 views

Why is entanglement so important if it introduces dependent information?

I still don't understand, why is entanglement such a crucial property of a quantum algorithm. If I understand it, it means that the information between different qubits is somehow correlated, which ...
sitems's user avatar
  • 363