# Creating Bell states (a question from tutorial) [closed]

I was going through a Quantum Computation lecture series on YouTube given by Umesh Vazirani. There in Lecture 6.3 he talks about creating a Bell state using a Hadamard and CNOT gate. He seems to be using |0⟩ and |1⟩. Is he talking about measuring a qubit in 0-1 basis and then using the qubits that gave 0 as a result for the |0⟩. Here is an image for reference.

• Hi and welcome to Quantum Computing SE. I am a little bit confused by your question. Could you please be more specific? Do you have a problem with understanding how to create different Bell states? Or outcome of measurement? Mar 29 '20 at 8:54
• I was having a problem trying to understand what |0⟩ meant as I thought qubits were always said to be in terms of probability. But, after a little bit of google now i understood it. So, I'm closing this question now. Thank you for your help anyways... Mar 29 '20 at 17:15

There is no measurement in the picture; the picture shows how to construct 4 Bell states $$|\Phi^+\rangle$$, $$|\Phi^-\rangle$$, $$|\Psi^+\rangle$$ and $$|\Psi^-\rangle$$ using Hadamard-CNOT circuit.