For a possibly unstable normal mode, ensures never vanishes, so choose one continuous branch of . Substitute into the Taylor–Goldstein equation and collect terms:
Multiplication by puts its first two terms in divergence form:
Multiply by the complex conjugate and apply integration by parts. Since , the boundary term vanishes and the power-transformed Taylor–Goldstein energy identity is
The weight is , not : preserving its complex phase is essential for the subsequent stability proofs.
Since , the complex conjugate gives
Therefore
Factor the expression using the complex conjugate:
It is real, so
The one-dimensional Time-dependent Schrödinger equation for a wavefunction in a real potential is
Multiplying this equation by , multiplying its complex conjugate by , and subtracting gives the probability continuity equation
If and its first derivative decay sufficiently rapidly as , then the probability current vanishes at both ends. Integrating the continuity equation and using the fundamental theorem of calculus yields
This conservation of quantum probability is required by the Born rule: once a normalizable wavefunction has total probability one, its time evolution must preserve that normalization.
For the stated Gaussian wave packet, put . Since
its squared modulus is
The Gaussian integral then gives
which is independent of time, as required.
The Dirac field Lagrangian is
Choose the Majorana spinor
Substitution shows that its two chiral kinetic terms agree after integration by parts and that
Thus equals twice the displayed one-Weyl-field Lagrangian, up to a total derivative.
The lower chiral component of the Dirac equation is
Putting gives exactly ; the upper component is its complex conjugate.
Write . Parity reverses the spatial coordinates and must exchange the two chiral Weyl spinors. One convenient choice is
The identities and exchange the two kinetic terms after . The mass bilinear maps to its complex conjugate , so the two mass terms are exchanged and the action is invariant. More generally, independent unit phases may multiply the two transformations provided .
For , the preceding change of variables and one integration by parts give
Split the last improper integral at one and add and subtract one on . Since ,
The definition also gives the complex conjugate relation
Consequently, for ,
For functions on , the Gowers inner product is
where is the complex conjugate operator. The Gowers uniformity norm is
The Gowers-Cauchy-Schwarz inequality states
The symmetric form of the functional equation of the Riemann zeta function is
The complex conjugation identity and the functional equation show that every Nontrivial zero of the Riemann zeta function is accompanied by , , and .
Let be the given nonreal zero. If , use itself; if , use , whose real part is . The resulting zero cannot have real part greater than one, by the stated zero-free half-plane. It therefore has real part in .
Write , with because the triangle is nondegenerate. Let be its circumcenter. Equality of the complex modulus values gives . Equality of , after expanding the squares, gives
Thus the real part and imaginary part determine
Using the complex conjugate , we also have
Therefore
The nonzero denominator is exactly the nondegeneracy condition. If is real, the three distinct collinear points do not have a finite circumcenter.
The product rule gives and . On an interval avoiding , substitution and division by give
For a constant-coefficient differential equation, the coefficient of forces . At , the remaining coefficient also vanishes. Thus
The characteristic equation of a constant-coefficient differential equation is , with complex conjugate roots of a polynomial . Its real solutions and are linearly independent. Therefore the general solution is
The constants can be chosen independently on the two sides of the singular point. The power substitution reducing a differential equation to constant coefficients here is invertible wherever .
The quadratic formula gives . For , write this as
Each root of a polynomial has modulus , since . As increases from to , the upper root traverses the upper unit semicircle from to , and the lower root traverses the lower semicircle in the opposite angular direction. At the roots coincide at ; at they coincide at . For intermediate they are complex conjugates.
Figure 1.
The conjugate roots travel along the two unit semicircles
. Arrows show increasing , with endpoints and and the midpoint pair . The figure is an original plot of the solution formula. Details.
Multiply numerator and denominator by the complex conjugate of . For this gives
Thus its real part and imaginary part are respectively
Multiply numerator and denominator by the complex conjugate of the denominator:
Squaring gives . Thus the real part and imaginary part are