The end of the quantum tunnel: Exact instanton transseries for quantum mechanics
Phys.org -

In the quantum world, processes can be separated into two distinct classes. One class, that of the so-called "perturbative" phenomena, is relatively easy to detect, both in an experiment and in a mathematical computation. Examples are plentiful: the light that atoms emit, the energy that solar cells produce, the states of qubits in a quantum computer.

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