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Equation 12 · Part 2 · From Origins to Frontier: A History of Quantum and Condensed-Matter Systems

subscript

TcT_c
subscript

What this part means

The lower label selects a particular version, component, or indexed member of the quantity. For example, x₀ and xₜ can be values at different positions.

Its job in the formula

A subscript distinguishes a version, component, step, or member of a quantity. It does not automatically mean multiplication.

The passage around this formula

No part of this history attracts more overclaiming than the search for a superconductor that needs no refrigeration at all. The physical logic for looking at hydrogen-rich compounds under extreme pressure is sound and traces to a real prediction: hydrogen, compressed enough, should behave like a light, strongly-bonded lattice with a very high phonon frequency ωD\omega_D — precisely the quantity that the BCS formula above says should raise TcT_c . Superconductivity near 203 kelvin was confirmed in compressed hydrogen sulfide in 2015 and above 250 kelvin in a lanthanum hydride in 2019, both under pressures around 150–200 gigapascals — genuine, independently reproduced results, though far from…

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Learn the underlying idea

A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.

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Sources cited in the article section

These citations provide research context; check each source for the exact claim it supports.