Spinors | Mathematical identities

Fierz identity

In theoretical physics, a Fierz identity is an identity that allows one to rewrite bilinears of the product of two spinors as a linear combination of products of the bilinears of the individual spinors. It is named after Swiss physicist Markus Fierz. The Fierz identities are also sometimes called the Fierz–Pauli–Kofink identities, as Pauli and Kofink described a general mechanism for producing such identities. There is a version of the Fierz identities for Dirac spinors and there is another version for Weyl spinors. And there are versions for other dimensions besides 3+1 dimensions. Spinor bilinears in arbitrary dimensions are elements of a Clifford algebra; the Fierz identities can be obtained by expressing the Clifford algebra as a quotient of the exterior algebra. When working in 4 spacetime dimensions the bivector may be decomposed in terms of the Dirac matrices that span the space: . The coefficients are and are usually determined by using the orthogonality of the basis under the trace operation. By sandwiching the above decomposition between the desired gamma structures, the identities for the contraction of two Dirac bilinears of the same type can be written with coefficients according to the following table. where The table is symmetric with respect to reflection across the central element. The signs in the table correspond to the case of commuting spinors, otherwise, as is the case of fermions in physics, all coefficients change signs. For example, under the assumption of commuting spinors, the V × V product can be expanded as, Combinations of bilinears corresponding to the eigenvectors of the transpose matrix transform to the same combinations with eigenvalues ±1. For example, again for commuting spinors, V×V + A×A, Simplifications arise when the spinors considered are Majorana spinors, or chiral fermions, as then some terms in the expansion can vanish from symmetry reasons.For example, for anticommuting spinors this time, it readily follows from the above that (Wikipedia).

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Catalan's Identity for Fibonacci Numbers

We prove Catalan's identity involving Fibonacci numbers using an interesting property of matrices known as the determinant sum property. This is similar to two other identities which we proved in the following videos: Cassini's Identity: https://youtu.be/pn0J0p0R_GM d'Ocagne's Identity: h

From playlist Identities involving Fibonacci numbers

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Cassini's identity | Lecture 7 | Fibonacci Numbers and the Golden Ratio

Derivation of Cassini's identity, which is a relationship between separated Fibonacci numbers. The identity is derived using the Fibonacci Q-matrix and determinants. Join me on Coursera: https://www.coursera.org/learn/fibonacci Lecture notes at http://www.math.ust.hk/~machas/fibonacci.pd

From playlist Fibonacci Numbers and the Golden Ratio

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An infinite product involving Fibonacci numbers!

After sketching two proofs of the closed form of the Fibonacci numbers, we find the value of an infinite product involving this famous sequence. http://www.michael-penn.net http://www.randolphcollege.edu/mathematics/

From playlist Identities involving Fibonacci numbers

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Quadratic Identities (1 of 2: By comparison of coefficients)

More resources available at www.misterwootube.com

From playlist Polynomials (related content)

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Fibonacci Mystery - Numberphile

Brady's view on people who write: "FIRST" - http://youtu.be/CmRh9tFYC68 More links & stuff in full description below ↓↓↓ Dr James Grime on the Pisano Period - a seemingly strange property of the Fibonacci Sequence. Available Brown papers: http://periodicvideos.blogspot.co.uk/2013/09/brow

From playlist James Grime on Numberphile

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The Millin Series (A nice Fibonacci sum)

We derive the closed form for the Millin series, which involves reciprocals of the 2^nth Fibonacci numbers. We use Catalan's identity, the convergence of a subsequence, and the golden ratio. Catalan's Identity: https://youtu.be/kskAtiWC_w8 Another reciprocal Fibonacci sum: https://youtu.b

From playlist Identities involving Fibonacci numbers

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STAIRS reveal the relationship between Fibonacci and combinatorics

Part I: https://youtu.be/Hl61mJxILA4 Source of the beautiful thumbnail: https://www.videoblocks.com/video/winter-stargate-deep-space-fibonacci-spiral-infinite-zoom-scl2tvcpliylych5s I am still surprised at why I have not thought of this more direct linkage between Fibonacci numbers and c

From playlist Fibonacci

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Generating Functions and Combinatorial Identities

We describe one method of manipulating generating function to produce new combinatorial sum identities. We include an application of finding the value of a certain sum involving Fibonacci numbers. http://www.michael-penn.net http://www.randolphcollege.edu/mathematics/

From playlist Identities involving Fibonacci numbers

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What do Fibonacci numbers have to do with combinatorics?

Part II: https://youtu.be/_RHXmGWXUvw Note: You ABSOLUTELY DON'T NEED TO HAVE KNOWN ANY COMBINATORICS because the combinatorics required in this video would be explained thoroughly. Source of the beautiful thumbnail: https://www.videoblocks.com/video/winter-stargate-deep-space-fibonacci-

From playlist Fibonacci

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Decentralized Identity - Bonus Livestream Session

Decentralized Identity. it just sounds cool, right? But what is decentralized identity? Can you use it now? How might it be used in the future? Watch this video to learn about all of this and more! Chapters 0:00 Decentralized Identity Livestream Starts 1:04 Thank you Patrons 6:26 Introdu

From playlist Decentralization: DeFi, DID, DEX and more

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Trig identities - What are they?

► My Trigonometry course: https://www.kristakingmath.com/trigonometry-course Trig identities are pretty tough for most people, because 1) there are so many of them, and 2) they’re hard to remember, and 3) it’s tough to recognize when you’re supposed to use them! But don’t worry, because

From playlist Trigonometry

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How to Prove Trigonometric Identities (Precalculus - Trigonometry 24)

A very in-depth look at proving trigonometric identities. Several techniques are explored in many different examples of solving trig functions. Support: https://www.patreon.com/ProfessorLeonard

From playlist Precalculus - College Algebra/Trigonometry

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22C3: Digital Identity and the Ghost in the Machine

Speaker: Max Kilger "Once I Was Lost But Now I've Been Found" The demarcation line that used to separate your digital identity from your real world physical identity is rapidly disappearing. More seriously, it is permanently changing the way in which the world sees you and you see yourse

From playlist 22C3: Private Investigations

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YOU CAN'T USE EULER'S IDENTITY TO PROVE THE ANGLE SUM IDENTITIES! | Tricky Parts of Calculus, Ep. 4

I give multiple proofs of the angle sum identities sin(x+y) = sin(x)cos(y) + sin(y)cos(x) and cos(x+y) = cos(x)cos(y) - sin(x)sin(y) from different perspectives. I stress that a very common presentation of these formulas based on Euler's identity e^(ix) = cos(x) + i sin(x) is circular and

From playlist Math

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CERIAS Security: Protocols and Systems for Privacy Preserving Protection of Digital Identity 1/5

Clip 1/5 Speaker: Abhilasha Bhargav-Spantzel In this presentation I introduce a number of techniques that address the above problems. The approach is based on the concept of privacy preserving multi-factor identity verification. The main technique consists of verifying multiple identi

From playlist The CERIAS Security Seminars 2007

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Introduction to Using Trigonometric Identities (Precalculus - Trigonometry 23)

A quick look at Trig Identities and how to use them. Basic identities such as the Pythagorean Identity, Reciprocal Identities, and Even/Odd Identities are explored. Support: https://www.patreon.com/ProfessorLeonard

From playlist Precalculus - College Algebra/Trigonometry

Related pages

Clifford algebra | Bilinear form | Dirac spinor | Spinor | Linear span | Trace (linear algebra) | Orthogonality | Linear combination