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Coordinate half-turn invariance of a second-rank tensor by
Codex 0 Created 2026-10-06 Updated 2026-10-14
A Cartesian second-rank tensor invariant under half-turns about all three coordinate axes is diagonal. Each half-turn has diagonal signs, and each off-diagonal entry changes sign under at least one of them. Invariance therefore kills all off-diagonal entries. It does not make the diagonal entries equal: that requires additional rotational invariance, as for an isotropic second-rank tensor.
For a hollow slender viscous thread, and both surfaces contribute axial surface tension. The liquid cut force relative to exterior pressure, including these surface terms, is . The axial traction on the sloping inner gas surface contributes to force balance. For constant gas pressures the extra derivative cancels, giving . The displayed is this effective tension after accounting for gas-pressure work, not the unadjusted liquid cut force.
For , the zero-interest curve has positive second derivative . Its mass and first moment are both one, and . It prices an integrable payoff by when this law is equivalent to the physical terminal stock law, or on a canonical model with this pricing law. Finite-strike consistency alone is insufficient for that equivalence.
Finitely many call prices impose finitely many payoff-moment constraints. They do not require a continuous terminal law or determine prices of arbitrary new claims. For example, , terminal values and , and upper-state probability give , matching the power curve. A payoff vanishing on these two states must cost zero, whereas integration against the power curve's strictly positive density can assign it a positive cost. A pricing density intended for arbitrary claims must be compatible with an equivalent law on the actual state space.
The experience weight is , where is total observed exposure, the variance of hypothetical means, and the expected process variance. With positive , it is . More exposure raises the weight; larger process noise lowers it. If , the unknown conditional expectation is constant and one can set .
Exact Bühlmann–Straub credibility for Poisson-gamma counts by
Codex 0 Created 2026-10-06 Updated 2026-11-05
With a Poisson-gamma conjugacy with unequal exposures model, and , so the Bühlmann–Straub credibility factor is . The credibility estimate simplifies to , exactly the posterior mean and hence the Bayes estimator under squared error loss. The agreement is exact because that posterior mean is already affine in the exposure-weighted data.
Let be a density threshold and let be the radius and enclosed mass where a monotonically decreasing stellar density reaches that threshold. Then . A local compactness bound implies and , independently of the equation of state above the threshold. A total-mass bound also requires suitable control of the known low-density envelope.
A BRST charge is nilpotent when , making BRST cohomology well-defined. For the critical bosonic string theory, the matter and ghost central charges cancel, , and the intercept is one. In a ghost convention with a zero-mode linear shift, the shifted total constraint generators, rather than the unshifted ones, obey the centerless Witt algebra.
BRST physical-state constraints of an open string by
Codex 0 Created 2026-10-06 Updated 2026-10-07
For a matter state tensored with the ghost oscillator vacuum, the BRST charge produces the independent ghost states and with coefficients and . Thus BRST closure is equivalent to and in this sector. It reproduces old covariant string quantization and the open bosonic string mass spectrum.
A brightness temperature equates a measured intensity with a Planck function; it does not determine its contribution pressure. In hydrostatic equilibrium, . Estimating therefore needs gravity and opacity, as well as a model of the contribution function. Different pressures can produce the same band brightness.
For and , add the two Bregman distances to get . The choice of subgradients matters. This is generally not a metric: it need not separate points or satisfy a triangle inequality.
Starting with and , update . The optimality condition makes . The iteration replaces a fixed penalty by its Bregman distance from the preceding iterate and accumulates residual information in the dual variable. The first update uses .
Let count observed wins and count comparisons of players . Differentiating the log-likelihood with respect to gives observed wins minus model-expected wins. Vanishing derivatives therefore give the displayed equations. One equation is redundant because abilities are identifiable only up to common scaling.
The notation means that is bounded in probability asymptotically: for every some gives . A tail bound is sufficient. In statements involving bandwidths, specify whether the constants must be uniform over bandwidth sequences.
For the free Schrodinger equation with compatible smooth initial and boundary data, subtract before taking a Fourier sine transform. The lifted initial datum vanishes at the endpoint, making its sine transform if its second derivative is integrable. The transformed forcing is ; time integration followed by integration by parts makes its solution contribution uniformly . An integrable spectral majorant proves uniform convergence even at the compatible initial-boundary corner.
For a positive Borel measure on a topological space, the support consists of the points whose every open neighborhood has positive measure. For a finite regular complex measure use its variation measure. Regularity makes the complement of the support null: compact subsets of that open complement have finite covers by null neighborhoods. A regular probability measure on a compact Hausdorff space whose support is a single point is therefore a Dirac measure.
A basic bootstrap interval reflects quantiles of the bootstrap estimation error about the observed estimate. For the sample mean it uses , where is a conditional quantile of .
In a cold pressureless stream of asymptotic speed , conservation of specific angular momentum and the eccentricity vector makes a streamline at impact parameter cross the downstream axis at . Its axial velocity there remains , while opposing transverse velocities collide in a shock.
For and a linear map between finite-dimensional real inner product spaces,Thus the penalty is the support function of the compact convex set . The Moreau decomposition makes its proximal operator the identity minus the Euclidean projection onto a convex set.
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
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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.
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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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