I am reading an introduction to quantum computing and I have a question about one thing I dont understand.(adsbygoogle = window.adsbygoogle || []).push({});

"In classical physics, the possible states of a system of n particles, whose individual states can be described by a vector in a two dimensional vector space, form a vector space of 2*n dimensions. However, in a quantum system the resulting state space is much larger; a system of n qubits has a state space of 2^n dimensions."

Its the dimensions thing that confuses me. Lets say we have 3 classical bits of information. There are 2^3=8 possible unique configurations of these three bits, so there are 8 states.

So the above asserts that these three bits have 2*3=6 dimensions, which makes sense because each bit has 2 possible states and thus there are six different numbers involved.

Now consider three qubits. They apparently have 2^3=8 dimensions. Could someone explain this? And how many states do they have? I would have assumed that because of superposition they would have something like the original 8 states plus all combinations of these. Is that the right idea?

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Possible States of n Qubits as opposed to classical bits

Loading...

**Physics Forums | Science Articles, Homework Help, Discussion**