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FriendlyLagrangian
  • Member for 2 years, 5 months
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8 votes
2 answers
1k views

Proof that you can't disentangle two parties if you only operate on one

6 votes
3 answers
604 views

What is meant in condensed matter physics by a “gap” and why is it so important?

6 votes
1 answer
187 views

Why is the electromagnetic duality an S-duality?

6 votes
2 answers
434 views

Canonical commutation relationship with general operators?

5 votes
2 answers
281 views

Lindblad equation unitary term (in practice)

5 votes
3 answers
880 views

Chemical potential in canonical partition function

5 votes
1 answer
269 views

Why does the "entanglement entropy" provide a necessary and sufficient condition for bipartite entanglement?

4 votes
1 answer
89 views

Technique for diagonalising this quadratic fermionic operator?

4 votes
1 answer
283 views

Is there a notion of a "Majorana boson"?

4 votes
0 answers
170 views

Why is the Jordan-Wigner transformation an example of an S-duality?

4 votes
2 answers
230 views

Hilbert space of a spinless fermion?

4 votes
1 answer
409 views

Proof that the reduced density matrix of free fermions is thermal?

4 votes
1 answer
146 views

Quantum relaxation to equilibrium?

3 votes
0 answers
97 views

Vacuum state after diagonalising a free Hamiltonian?

3 votes
1 answer
131 views

How is it acceptable that the Lindblad equation typically depends on a Cauchy principal value?

3 votes
1 answer
374 views

Kramers-Wannier duality high and low temperature expansions confusion

3 votes
2 answers
96 views

Why does entanglement negativity not satisfy the triangle inequality in the usual sense?

3 votes
0 answers
66 views

Is it possible to express any quadratic fermionic system in terms of a quadratic majorana system and viceversa?

2 votes
2 answers
199 views

Proof of this version of Wick’s theorem?

2 votes
1 answer
106 views

Is the sum of two gaussian density matrices also gaussian?

2 votes
2 answers
93 views

The 2-point correlation matrix $C_{ij}$ fully characterises a free eigenstate $|\psi\rangle$, what characterises a superposition of eigenstates?

2 votes
1 answer
272 views

Can you represent a diagonal density matrix with creation/annihilation operators?

2 votes
0 answers
78 views

Interacting fermionic models with exact analytical solution?

2 votes
0 answers
117 views

How to compute the standard deviation of a free fermionic random correlation matrix

2 votes
0 answers
76 views

Why does the no-cloning theorem imply the monogamy of entanglement?

2 votes
1 answer
146 views

When in $T \rightarrow \infty$ the eigenstates that contribute the most are the ones that lie in the middle of the spectrum?

2 votes
1 answer
277 views

Is there a notion of a "reduced" Hamiltonian?

2 votes
1 answer
47 views

Why is $\sum_{i=0}^N S_i^z S_{i+1}^z |\uparrow ... \downarrow_n ... \uparrow \rangle = \frac{1}{4}(N-4)$?

2 votes
1 answer
165 views

1d atom chain continuum approximation

2 votes
1 answer
235 views

Thermodynamic equation of differentials (and how to work with them)