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For , a full star graph requires every nonincident edge to be certified absent, and fixing those bits suffices. Rejection is certified by at most three present edges with empty common intersection; a triangle needs all three. Hence query certificate complexity is for this property.
If preserves small categorical limits, the projection creates the small categorical limits available in . A categorical cone of arrows induces a unique arrow by preservation; this equips the underlying categorical limit with its comma category structure. The universal property proves that every categorical cone factorization preserves that structure.
The slice over has morphisms as objects and commuting triangles as arrows . Its terminal object is , regardless of whether has a terminal object. It is the comma category , viewing as a functor from the terminal category.
The dimensional matter power spectrum contains a factor , rather than . The cosmological transfer function tends to one below the matter-radiation equality scale and to above it. The smooth spectrum therefore scales as at small wavenumber and at large wavenumber. The logarithmic factor records slow cold-matter growth during radiation domination. Multiplying by instead produces dimensionless matter power.
Suppose is an exact sequence of pro-p groups, with abelian and . Conjugation gives a compact Galois module structure. The closed commutator subgroup is : its image is closed by compactness, and after quotienting by it, a lift of centralizes and topologically generates the remaining quotient. Hence is exact.
An antiperiodic free fermion field with inverse propagator has a thermally normalized determinant . The factor counts empty and occupied states of one level. Its logarithmic Matsubara sum is meaningful only with a regularization fixing the determinant normalization; an unqualified infinite product is not convergent.
A CNOT gate can correlate either the original control's computational label with a computational pointer, or the original target's sign-basis label with a sign-basis pointer. For the second interpretation prepare the original control in and read it in the Hadamard basis. Its two pointer states become and , measuring on the original target. An apparatus role therefore depends on the ready state and readout as well as the measurement interaction.
The design effect is a sampling variance under a complex design divided by the corresponding simple-random-sampling variance. For independent equal-size clusters of size with exchangeable intraclass correlation , a common mean-estimation approximation is . It expresses the loss of effective sample size from positive correlation; finite-population and unequal-cluster-size designs require their own calculation.
For an irreducible variety which is an affine variety of dimension and a nonzero nonunit regular function , each irreducible component of has dimension . Choose a closed point on just the component in question. In its local ring , is that component's prime ideal. A system of parameters of , lifted and supplemented by , generates a maximal-primary ideal; the Krull height theorem gives . Extending any chain above by the zero prime of the domain gives the reverse inequality. This proof does not identify dimension with transcendence degree.
A linear map between Fréchet spaces is continuous if its graph of a linear operator is closed in . The closed graph is itself a Fréchet space. Its first-coordinate projection is a continuous linear bijection onto , so the open mapping theorem for Fréchet spaces makes the inverse continuous. Compose that inverse with the second-coordinate projection to obtain . Completeness of both original spaces is part of the theorem.
The nonnegative integer laws whose probabilities satisfy this recurrence for all . Their probability generating function solves . This is the count class used in the Panjer aggregate algorithm; the count recurrence itself should be distinguished from that aggregate recursion. It includes the Poisson distribution, binomial distribution, and negative binomial distribution with suitable parameters.
The circuit value problem restricted to AND and NOT gates remains P-complete. Replace each OR by , using a constant-size gadget. Gate indices and gadget positions can be emitted in logarithmic space, and assignments are preserved. Constants, when needed, can be represented by fixed-valued input nodes.
OR together one minterm for each accepted length- input. Each minterm is an AND of the appropriate Boolean literals. There are at most minterms, and their negated input wires can be shared, giving bounded-fan-in gates. This is a nonuniform existence statement, not an algorithm for determining an undecidable truth table.
For spin-projective measurements on a two-qubit state, let be the eigenvalues of , where is its Pauli correlation tensor. Bob's sum and difference of unit axes are orthogonal and have lengths and . Maximizing Alice's two axes aligns them with the corresponding images under . Maximizing then gives for orthonormal . The maximum of this quadratic-form sum is , by diagonalizing and selecting its top two eigenvectors. Thus the displayed expression is both an upper bound and attainable. The same maximum applies to the form with the sum of two absolute values, since local outcome signs can select their positive branches.
For fixed and , Janson inequality bounds the failure probability for a given large vertex subset by . A union bound over all at most subsets still tends to zero. This uniform statement is essential because vertex sets left by a greedy colouring procedure depend on the graph; one cannot assume each adaptively chosen remainder is an independent fresh random graph.
A Dirichlet character with even parity satisfies , so its extension to integer arguments is an even function.
A Dirichlet character with odd parity satisfies , so its extension to integer arguments is an odd function.
Characters distinguish finite-dimensional complex semisimple representations by
Codex 0 Created 2026-10-07 Updated 2026-11-05
For any group, take the group-algebra image on the direct sum of two finite-dimensional complex semisimple representations. Its radical annihilates their simple summands and hence the faithful direct sum, so the image algebra is semisimple. Equality of traces on group elements gives equality on their linear span. Traces on primitive central blocks then recover every simple multiplicity, proving that equal characters imply isomorphism.
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:
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
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