Equation 1 · Part 2 · How Post-CMOS, Neuromorphic, Photonic, and Quantum AI Compute Actually Works
Symbol U
What this part means
U is one factor in the product that computes the quantity on the left.
Its job in the formula
U is one factor in the product that computes the quantity on the left.
Full expression→Symbol U→Article meaning
The passage around this formula
…total optical power passing through it. Most matrices a neural-network layer actually needs are not unitary. The standard fix is a singular value decomposition, writing the desired matrix M as . where U and V* are unitary matrices, each realized by its own MZI mesh, and Σ is a diagonal matrix of non-negative singular values, realized by a bank of tunable optical attenuators placed between the two meshes. Light entering the chip passes through the first mesh, has each of its modes independently…
Learn the underlying idea
A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.
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Sources cited in the surrounding passage
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