Symbol T
T is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Read this term in its guide →Published equation contexts
Why this formula appears here
The best-established non-trivial quantum effect in biology generates none of the excitement the other three cases have attracted, largely because it never needed a correction: enzymatic hydrogen transfer has been recognized as a quantum-tunneling phenomenon, not a classical over-the-barrier reaction, since kinetic isotope effect measurements in the 1980s and 1990s began returning numbers no classical transition-state theory could accommodate. A classical reaction’s kinetic isotope effect — the rate ratio between a protium-substituted and a deuterium-substituted substrate — is bounded by the difference in zero-point vibrational energy between the two isotopes, which caps the semiclassical…
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Symbol E
E is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Read this term in its guide →Symbol x_1
appears in the bound of this integral. The bound states where the repeated operation starts, ends, or which values it includes.
Read this term in its guide →Symbol x_2
appears in the bound of this integral. The bound states where the repeated operation starts, ends, or which values it includes.
Read this term in its guide →Symbol m
m is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Read this term in its guide →Symbol V
V is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Read this term in its guide →Symbol x
x appears in the bound of this integral. The bound states where the repeated operation starts, ends, or which values it includes.
Read this term in its guide →Symbol d
d is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Read this term in its guide →Denominator: hbar
The complete quantity below the fraction bar; it must be nonzero for this division.
Read this term in its guide →Starting index or lower bound: x_1
This label says where the repeated addition, multiplication, or accumulation starts. Read its value or condition together with the article’s description of the index.
Read this term in its guide →Ending index or upper bound: x_2
This label says where the repeated addition, multiplication, or accumulation stops. It sets the last term or end of the range.
Read this term in its guide →How to interpret it
With a fixed numerator, increasing a nonzero denominator reduces the fraction. Its accuracy depends on the assumptions and range of use described in the article.
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Published contexts (1)
A symbol can carry a different meaning in another article. Each occurrence keeps its own guide and term definitions.
Equation 1 · Evolutionary Physics
What Evolution Actually Found in the Quantum Toolbox
This equation gives an approximation: it relates the quantities while allowing an approximation.
The best-established non-trivial quantum effect in biology generates none of the excitement the other three cases have attracted, largely because it never needed a correction: enzymatic hydrogen transfer has been recognized as a quantum-tunneling phenomenon, not a classical over-the-barrier reaction, since kinetic isotope effect measurements in the 1980s and 1990s began returning numbers no classical transition-state theory could accommodate. A classical reaction’s kinetic isotope effect — the rate ratio between a protium-substituted and a deuterium-substituted substrate — is bounded by the difference in zero-point vibrational energy between the two isotopes, which caps the semiclassical…
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