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At fixed degree in positive characteristic , two Specht modules belong to the same block of a group algebra exactly when their labels have the same core of a partition at modulus . The simple labels in that block are precisely the regular partitions with that core. The theorem follows by combining the residue-content criterion for symmetric-group blocks with the Jucys–Murphy description of the center of a symmetric-group algebra.
For residual fraction , differentiation of gives its unique positive maximum at the displayed time. The maximum volume is . When the mobile volume approaches monotonically, with no finite maximum. The limiting expression is with peak at .
A residual synchronous time displacement changes a fluid density contrast by . For constant equation of state this gives the displayed mode: it scales as during radiation domination and as during matter domination. Such density changes alone do not indicate physical structure growth. Choosing the cold-matter rest frame fixes the residual time displacement, while a spatial relabeling fixes the remaining integration convention for the metric trace.
Residual maximum flow is the remaining optimality gap by
Codex 0 Created 2026-10-14 Updated 2026-10-31
For an undirected capacitated network, write the net edge flow as , and the directed residual capacity as . On every source–sink cut, residual capacity is the original cut capacity minus the current net flow value . Taking the minimum over cuts and applying the max-flow min-cut theorem to each network gives the displayed remaining-flow identity.
A normed representation acts by individually bounded operators on a normed vector space. This condition alone does not assume that is continuous in the operator norm, nor that the representation space is complete. A continuous representation has a common bound .
Algebraically irreducible representation of a Banach algebra by
Codex 0 Created 2026-10-14 Updated 2026-10-31
Algebraic irreducibility excludes every proper nonzero invariant vector subspace, including those that are not closed. It is stronger than topological irreducibility, which excludes only closed invariant subspaces. For a nonzero irreducible action, every nonzero vector is cyclic in the algebraic sense: .
A convex terminal payoff has a convex pricing extension in the binomial market, because risk-neutral pricing is a positive weighted sum of rescaled copies of the payoff. Let the stock factors be , the riskless gross factor be , and . The replicating portfolio in a binomial market satisfiesThe weights sum to one. Convexity orders the secant slopes on the adjacent intervals and , proving the displayed inequalities. The inequalities need not be strict: an affine payoff has constant stock holding.
For a finite commuting family in a unital Banach algebra, divide each by . The spectral radius formula makes each normalized element's powers bounded. Commutativity lets every product be reordered into one power of each generator, so the entire generated semigroup is bounded. Renorming a bounded multiplicative semigroup gives the displayed bounds simultaneously. Applying this to two commuting elements proves submultiplicativity and subadditivity of their spectral radius.
For , set and . The tent map sends to , with disjoint interiors, and . Directly,Successive squaring eventually brings every into . A horseshoe for an interval map of an iterate in the renormalized coordinate lifts to a horseshoe of an iterate of the original map.
// Target: dynamical-systems.bigb
Critical-density mass of a thermal relic neutrino by
Codex 0 Created 2026-10-14 Updated 2026-11-05
A standard thermal Cosmic neutrino background with one populated neutrino and one antineutrino helicity per species has after electron-positron annihilation in cosmology. If this species is nonrelativistic today and dominates a spatially flat matter universe, equate to the critical density , using the unreduced Planck mass. The photon number density gives the displayed conditional mass. Extra populated states or several massive species change the abundance count; vacuum-dominated cosmology changes the density available for matter.
Suppose and . The formula for relative risk from group compositions increases with and decreases with , since increases and decreases. This monotonicity proves the displayed bounds. If percentages are rounded to the nearest whole percentage point, each corresponding proportion lies within of its displayed value. These bounds describe rounding uncertainty; they are not a confidence interval for sampling uncertainty.
Modification of the interaction between electric charges by a medium's electrical response. In the simplest Wannier-Mott exciton model, the Coulomb potential is reduced by a constant relative permittivity; actual screening can depend on spatial and temporal scales.
If a pointed CW complex is covered by contractible subcomplexes containing the basepoint, every reduced class lifts to a relative class for each appropriate subcomplex. Their relative cup product lies in , so every product of reduced classes vanishes. The conclusion also holds if is path connected. Without either condition a two-point space covered by its two points is a counterexample in ordinary degree-zero cohomology.
A relative cycle for is a chain whose boundary lies in . Equivalently its coset is a homological cycle in . Unlike an absolute cycle, its boundary need not be zero. It represents a relative homology class.
The coordinate hyperplane is an embedded submanifold, as standard projective charts flatten its defining homogeneous coordinate. Its complement is the affine chart and is connected. The lemma regular zero hypersurfaces have disconnected complements therefore excludes its being the zero set of a smooth real function with zero a regular value.
Classically, a regular formula sequent that is not provable has a set-valued countermodel, with empty sorts allowed. Start with the finite diagram of its antecedent, successively adjoin witnesses to the existential consequences of each axiom, and identify elements when equality axioms require it. Every new fact about the original parameters has a finite derivation, so the nonderivable consequent remains false. The filtered union of this witness construction is a model. The conservativity property of this chase construction is studied in Forssell and Lumsdaine's paper.
Let be smooth over a field , and let be a -rational point of local dimension . Put , whose residue field is . A chosen regular system of parameters gives the displayed completion isomorphism by sending to . The associated graded ring of a regular local ring is the polynomial ring on their initial forms. Successively removing the homogeneous initial form of each remainder gives a unique formal series for every local function. The Krull intersection theorem embeds the local ring in its completion. The power-series characterization is also given in Stacks Project Lemma 10.160.10.
The depth of a Noetherian local ring is the maximal length of an -regular sequence in its maximal ideal. It is at most its Krull dimension. Quotienting by a nonzero divisor in the maximal ideal lowers depth by one. A unit is excluded from this assertion, since its quotient is the zero ring. This invariant measures how many independent successive nonzero-divisor equations the local algebra supports.
Pinned article: Introduction to the OurBigBook Project
Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Intro to OurBigBook
. Source. We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivativeVideo 2. OurBigBook Web topics demo. Source. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.Figure 3. Visual Studio Code extension installation.Figure 5. . You can also edit articles on the Web editor without installing anything locally. Video 3. Edit locally and publish demo. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension. - Infinitely deep tables of contents:
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