Mahathi Vempati's user avatar
Mahathi Vempati's user avatar
Mahathi Vempati's user avatar
Mahathi Vempati
  • Member for 5 years, 9 months
  • Last seen more than a month ago
9 votes
1 answer
2k views

How can we be sure that for every $A$, $A^\dagger A$ has a positive square root?

9 votes
1 answer
540 views

Building Intuition for Relative Von Neumann Entropy

7 votes
2 answers
767 views

Is the set of all states with negative conditional Von Neumann entropy convex?

7 votes
3 answers
1k views

How do you send an array of qubits to an operation in Q#?

7 votes
4 answers
1k views

Maximally mixed states for more than 1 qubit

7 votes
3 answers
3k views

Partial trace over a product of matrices - prove that ${\rm Tr}(\rho^{AB}(\sigma^A\otimes I))={\rm Tr}(\rho^A\sigma^A)$

7 votes
2 answers
244 views

Are there disadvantages in using the inner product between states instead of the fidelity?

7 votes
2 answers
455 views

Diagrammatic Quantum Reasoning: Proving the loop equation using yanking equations

6 votes
1 answer
387 views

Equivalent determinant condition for Peres-Horodecki criteria

6 votes
2 answers
830 views

How does $\mathcal E(\rho)=\mathrm{Tr}_{env}[U(\rho\otimes\rho_{env})U^\dagger]$ turn into $P_0\rho P_0+P_1\rho P_1$?

5 votes
2 answers
285 views

Ways in which $\frac{1}{\sqrt 2} (|00\rangle + |11\rangle)$ can be expressed as $\frac{1}{\sqrt 2} (|uu\rangle + |vv\rangle)$

5 votes
1 answer
193 views

What are the standard eigenvalues in $\mathbb{C^2}\otimes\mathbb{C^2}$?

5 votes
2 answers
315 views

Shannon entropy is least when Measurement basis = Mixture basis

5 votes
2 answers
1k views

Why are $d^2$ dimensions required to describe a density matrix?

4 votes
1 answer
411 views

Difference between change of basis in bra-ket notation and matrix notation

4 votes
1 answer
104 views

Structural Physical Approximation of Partial Transpose

4 votes
1 answer
282 views

Are entanglement witnesses of this form optimal?

4 votes
1 answer
319 views

Proving the inequality $|\mathrm{tr}(AU)|\le \mathrm{tr}|A|$ in Uhlmann's theorem

4 votes
1 answer
374 views

How are witness operators physically implemented?

4 votes
0 answers
105 views

Deutsch Algorithm on a Quantum Turing Machine

4 votes
1 answer
183 views

How to find a separable decomposition for $|\Psi^+\rangle\!\langle\Psi^+|+|\Phi^+\rangle\!\langle\Phi^+|$?

4 votes
1 answer
255 views

Differentiate between local and global unitaries

4 votes
1 answer
261 views

How is the expression for the optimal entanglement witness derived?

3 votes
0 answers
86 views

What do you specify when you physically apply a unitary?

3 votes
1 answer
313 views

For 2x2 and 2x3 systems, is the partial transpose the only positive but not CP operation?

3 votes
1 answer
240 views

What can we know about the eigenvalues of a reduced density matrix knowing the eigenvalues of the original matrix?

2 votes
1 answer
127 views

What is the relevance of preservation of trace in completely postive trace preserving (CPTP) maps?

1 vote
1 answer
167 views

Quantum Fourier Transform on two qubits: Non orthogonal outputs

1 vote
2 answers
771 views

How to write a post-measurement state, if we don't know the measurement result?