Equation 27 · Part 1 · Every Crystal Has Its Own Speed of Light
Symbol c
What this part means
c is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Its job in the formula
c is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Full expression→Symbol c→Article meaning
The passage around this formula
…rather than merely in name. Near the point where graphene’s conduction and valence bands touch, its electrons obey a two-dimensional version of the massless Dirac equation, with the Fermi velocity standing in for c . Mikhail Katsnelson, Konstantin Novoselov, and Andre Geim used that fact in 2006 to predict something the vacuum makes almost impossible to see: a chiral, massless particle hitting an electrostatic barrier head-on tunnels through with perfect transmission, regardless of the barrier’s height or…
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
These citations provide research context; check each source for the exact claim it supports.