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Multi-scale Entanglement Renormalization Ansatz

Entanglement renormalization is a numerical technique that locally reorganizes the Hilbert space of a quantum many-body system to reduce entanglement in its wave function. It addresses the computational challenges of real-space renormalization group RG methods, which struggle with the rapid growth of degrees of freedom during successive RG transformations. The key idea is... read more

Entanglement-Assisted Quantum Error Correction

Let \(\mathscr{N}\) denote noise, \(\mathscr{R}\) denote the recovery process, and \(L(H)\) denote the linear operator acting on Hilbert space \(H\). The recovery process is given as \(\mathscr{N}, \mathscr{R}: L(H) \rightarrow L(H)\). Where the mapping can be represented as an operator-sum

\(\mathscr{N}(\rho)=\sum_i E_i \rho E_i^{\dagger},\) \(\quad E_i \in L(H),\) \(\quad \mathscr{N}=\left\{E_i\right\}\)

Given the quantum code \(C_{Q}\), a subspace of \(H\), there exists a recovery... read more

Seiberg-Witten Theory [in Topological Quantum Field Theory]

The formula in the case of \(SU(2)\) is as follows. Choose a polynomial \(Q\). For each \(k \in \mathbb{Z}_{+}\), let \(\xi(k, t)\) be the formal power series in \(t\) that represents a unique critical point of the function in \(\xi\).

\(F(\xi ; h, k, t)\) \(:=\frac{1}{2}(\xi-k)^2+t \cdot \frac{h}{2 \pi^2} \cdot Q(\pi \xi / h)\)
where, \(t\) is treated as a formal variable. \(\xi(k,t)\) undergoes \(t\)-series expansion near the minimum \(\xi(k,0)=k\), formulated as:

\(\displaystyle{ \int_{F(\Sigma ; G)} \exp \left\{h \omega+t \cdot[\Sigma] \backslash Q\left(u^* \phi_2\right)\right\} }\) \(\displaystyle{ =\# Z(G) \cdot h^{3 g-3} \operatorname{vol}(G)^{2 g-2} }\) \(\displaystyle{ \sum_{k>0}\left[\frac{1+\frac{t}{2 h} Q^{\prime \prime}(\xi(k, t))}{\xi(t, k)^2}\right]^{g-1} }\)
such that, \(\#Z(G)=2\) for \(SU(2)\)... read more

Riemannian Manifold

A Riemannian manifold is a smooth manifold \(M\) with a Riemannian metric denoted \((M,g)\). For every point \(p\in M\) the tangent bundle of \(M\) assigns a vector space \(T_{p}M\), termed the tangent space of \(M\) at \(p\). The Riemanniam metric defines a positive-definite inner product:

\(g_p: T_p M \times T_p M \rightarrow \mathbb{R}\)
with a norm \(|\cdot|_p: T_p M \rightarrow \mathbb{R}\) defined as:

\(|v|_p=\sqrt{g_p(v, v)}\)
...read more

Thalamic Nuclei

The thalamic nuclei are paired structures of the thalamus divided into three main groups: the lateral nuclear, medial nuclear, and anterior nuclear groups. The internal medullary lamina, a Y-shaped structure that splits these groups, is present on each side of the thalamus. A midline, thin thalamic nuclei, adjacent to the... read more

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