If $N_G(D)\le H\le G$, Brauer correspondence pairs the blocks of a group algebra of $RG$ and $RH$ having defect group of a block $D$. This is Green correspondence for their bimodules, with vertex of an indecomposable module $\Delta D$ in $G\times G$. The normalizer of $\Delta D$ lies in $H\times H$, and the corresponding restriction and induction have unique summands with that vertex.

The Green correspondent is the unique indecomposable summand of restriction or induction having the selected vertex of an indecomposable module, in the setting of Green correspondence. The two correspondence maps are inverse and preserve sources of an indecomposable module up to the appropriate normalizer conjugacy.

Let $N_G(D)\le H\le G$ and let $U$ be indecomposable with vertex $D$ over $H$. The Mackey restriction formula writes ${\mathrm{Res}}_H^G{\mathrm{Ind}}_H^{G}U=U\oplus T$, where the vertices in $T$ lie in $H\cap {}^{g}D$ for $g\notin H$. None of these subgroups contains an $H$-conjugate of $D$: equality would put $g$ in $N_G(D)H=H$. Every summand of the induction with a $G$-conjugate of vertex $D$ contributes a vertex-$D$ summand on restriction. Krull-Schmidt decomposition therefore forces exactly one such summand, with multiplicity one. Choosing sources and using transitivity of induction proves the inverse correspondence and preservation of sources.

Map a site $x\in {\mathbb{Z}}^d$ to its height $h(x)={\sum }_i{x}_i$. Maintain one infected representative in height $n$ for every infected site of an auxiliary one-dimensional contact process. The representative's death makes that auxiliary site recover. Its $d$ outgoing arrows to each neighbouring height, each of rate $\lambda$, make an auxiliary infection at total rate $d\lambda$, using the arrow's target as the new representative. Arrows to an already infected auxiliary height do nothing there. Distinct active representatives use distinct death and outgoing-arrow clocks, so their conditional rates are exactly those of the one-dimensional process. Every auxiliary infection has a live representative upstairs, proving the survival comparison.

For the one-dimensional contact process with recovery rate one and per-neighbour infection rate $\lambda$, use parity sites $(x,n)$ with $x+n$ even. Call a site good if $x$ has no recovery in $[(n-1)\delta ,(n+1)\delta ]$ and sends an arrow to each neighbour during $[n\delta ,(n+1)\delta ]$. The goodness indicators are independent: recovery intervals for successive parity sites at the same spatial point only touch at endpoints, and all outgoing-arrow intervals and clocks are disjoint. Their common probability is the displayed $q$. A path of good sites carries infection from each time layer to the next, because both its source and target avoid recovery during the transmitting interval. Taking $\delta ={\lambda }^{-1/2}$ makes $q\to 1$. The incoming-edge coupling of site and bond percolation and $p_c^{\mathrm{bond}}<1$ imply $p_c^{\mathrm{site}}<1$, so this proves a finite critical infection rate.

An indexed lambda term assigns a natural number to every subterm occurrence; one also admits a constant $\perp$ with empty interpretation. In the graph model of lambda calculus, every syntax constructor is interpreted as usual and then intersected with $\{0,\dots ,n\}$ at its occurrence index $n$. All indexed interpretations are finite subsets of the unindexed interpretation, and their directed union recovers that interpretation.

The interpretation of a lambda term in the graph model of lambda calculus is the union of the interpretations of all its finite Böhm approximants. Every finite indexed interpretation reduces monotonically to an indexed normal approximant. Taking the union over all occurrence indices gives one inclusion; replacing subterms by bottom and using beta soundness gives the other. This identifies denotational information with finite observable parts of a Böhm tree.

For differentiable vector fields, expand the cross products using the contraction of two Levi-Civita symbols. The directional-derivative terms cancel the corresponding terms in the two cross products, leaving ${\partial }_i(F_j{G}_j)$. This proves the displayed gradient identity by the product rule.

For a graded vector space $V$, $\mathrm{Sym}(V)$ is the quotient of the tensor algebra by $uv-(-1{)}^{|u||v|}vu$. Over $\mathbb{Q}$ it is polynomial on even-degree basis elements and exterior on odd-degree ones. With each generator primitive, it is a graded cocommutative Hopf algebra. Its primitive subspace is exactly $V$: applying the diagonal to a polynomial of symmetric length greater than one produces mixed terms, or equivalently the polynomial's formal derivatives cannot all vanish in characteristic zero. This is the associated graded algebra in the graded Poincaré–Birkhoff–Witt theorem.

If a good rate function has unique zero mu, every closed set missing mu has strictly positive infimum rate, possibly infinity. Otherwise a sequence of rates tending to zero lies eventually in the compact unit sublevel set; a subsequence converges to a point of the closed set, and lower semicontinuity makes that point another zero. Compactness also ensures existence of a zero whenever the infimum is zero.

The Goldstone-boson equivalence theorem reduces high-energy electroweak longitudinal scattering to scalar scattering. Without the radial Higgs boson, a nonlinear sigma-model description gives an amplitude of order $s/v^2$. In the corresponding linear scalar model, the contact and Higgs-exchange terms give, for the charged-to-neutral Goldstone channel,The growing terms cancel, leaving $-m_H^2/v^2$ at high energy. Thus the Higgs mechanism supplies both vector masses and the interactions required for controlled longitudinal scattering. The tree expression is not valid as an unresummed approximation arbitrarily close to the Higgs pole.

This diagonal sentence says that any proof of itself has a no-later proof of its negation. A proof of $R$ contradicts finite verification that no earlier opposite proof exists. A proof of its negation, together with finite verification that no earlier proof of $R$ exists, proves the displayed universal condition and hence $R$. Thus consistency alone excludes both proofs, strengthening the original omega-consistency form of incompleteness.

The Amrita Virtual Lab procedure uses $0.1\mathrm{mol}{\mathrm{L}}^{-1}$ glycine, hydrochloric acid and sodium hydroxide, two burettes, a pH meter, beaker and stirrer. A pipette transfers $20\mathrm{mL}$ of glycine into a $100\mathrm{mL}$ beaker. Calibrate the meter with standard buffer solutions at pH $4$, $7$ and $10$, then record the starting pH. Add hydrochloric acid in $0.3\mathrm{mL}$ increments, recording pH after each addition until $1.6$. Rinse the electrode in distilled water, take a separate fresh $20\mathrm{mL}$ portion, and add sodium hydroxide in $0.3\mathrm{mL}$ increments until pH $12.5$. Its observed readout is paired added volume and pH, plotted as an acid-base titration curve; it does not measure each glycine form directly. ^[ref]

These are two titrations from the starting glycine chemical solution, rather than the single acidified-sample protocol assumed by the solid curve in glycine titration. Retain each portion's initial volume and the signed added acid/base amount of substance; do not concatenate raw burette readings and assume the result begins at $b=0$. For this procedure's $0.00200\mathrm{mol}$ of glycine, each $0.3\mathrm{mL}$ addition supplies $0.000030\mathrm{mol}$ of acid or base, a $0.015$ increment relative to the glycine inventory. This calculated resolution is not a reported measurement.

Useful additional controls are a fresh repeat portion, independently checked acid/base concentrations, a water blank, and a calibration-check buffer solution after the run. Stir without striking the glass electrode, keep its sensing region immersed and wait for stable readings; record temperature and background salts. Reduce addition size near a steep pH change. These are suggested controls for testing the model, beyond the published steps. A water blank can reveal contamination but must not be subtracted directly from pH, which is a logarithm.

The standards at pH $4$, $7$ and $10$ do not bracket either endpoint of this protocol. Extreme readings therefore require independently checked instrument performance, and alkaline samples are sensitive to atmospheric carbon dioxide uptake. Electrode drift, incomplete mixing, volume error, dilution and changing ionic strength can shift apparent pKa values. A titration constrains the acid/base model; it cannot establish chirality or separate every microscopic protonation form. The two original diagrams show calculated predictions to compare with measured points, not reconstructed experimental data.

On a fixed finite horizon, equivalent probability measures have the same semimartingales. For a strictly positive continuous Radon-Nikodym density martingale $Z$ and a continuous local martingale $L$ under the original measure, $L-\int Z^{-1}d[L,Z]$ is a local martingale under the new one, by the Girsanov theorem. Thus the finite-variation part of a continuous semimartingale decomposition changes by the opposite covariation correction.

Under a reference measure where $X$ is Brownian motion started at zero, let $T$ be its exit time from $(-1,1)$. The displayed density is the stochastic exponential with integrand $X{1}_{[0,T]}$, by the Itô formula. It is bounded by $e^{1/2}$, hence defines a uniformly integrable density process with terminal density $Z_T$. Under that measure change, $X_t-{\int }_0^{t\wedge T}{X}_{s}ds$ is Brownian motion. At exit, $Z_T\ge e^{1/2-T}$, implying $\mathbb{P}(T\le t)\ge e^{1/2-t}\tilde{\mathbb{P}}(T\le t)$. This is a terminal density on the whole probability space, not merely an unspecified finite-horizon change of measure.

On each finite horizon the displayed Radon-Nikodym derivative changes Wiener measure into the law of $dX=dB-\mu Xdt$. Stop at coordinate magnitude n so the Novikov condition applies. Under each stopped tilted measure the coordinate solves the drifted equation, and the Gronwall inequality with the Doob L2 maximal inequality bounds its maximal second moment uniformly in n. The probability of reaching n therefore tends to zero; this proves that the unstopped density has expectation one. No unrestricted large-time Novikov estimate is needed.

With the full boundary metric fixed, first variation gives $d_x{d}_g(w)=-⟨v_{\mathrm{in}},w⟩$ and $d_y{d}_g(z)=⟨v_{\mathrm{out}},z⟩$ for tangential endpoint variations. These covectors recover the tangential parts of both unit velocities. Their normal components follow from unit length and the inward/outward sign, so equal boundary distances give equal scattering relations. Without a fixed boundary metric, the bundle identification must first be gauged by a boundary-fixing diffeomorphism.

For $f=1-2M/r$ and squared areal radius $C=r(r-b)$, an equatorial null geodesic obeys ${\dot{r}}^2=E^2[1-B^{2}f/C]$, with impact parameter $B=L/E$. At $b=2M$, $f/C=1/r^2$ in the exterior. Its supremum is $1/(4M^2)$ at the null singular boundary, rather than at a regular exterior photon sphere. Rays with $B>2M$ turn at $r=B$; rays with $B<2M$ reach the boundary. Assuming those rays are absorbed gives the displayed geometric-optics cross-section despite zero limiting horizon area.

The radial direction is orthogonal to the angular directions under the exponential map. On a surface this makes the first fundamental form in geodesic polar coordinateswith $\sqrt{G(r,\theta )}/r\to 1$ as $r\to 0$.

For $r$ smaller than the normal-coordinate radius, the geodesic circle on a Riemannian surface consists of points at distance $r$ from $p$. The exponential map restricted to the radius-$r$ circle in $T_{p}S$ gives its smooth embedded parameterization. Outside the injectivity range a distance sphere need not be smooth.