
	Where results make sense

Topic: Dirac spinor

Related Topics

Spinor

Pauli matrices

	Dirac equation - Wikipedia, the free encyclopedia
		In physics, the Dirac equation is a relativistic quantum mechanical wave equation formulated by British physicist Paul Dirac in 1928 and provides a description of elementary spin-½ particles, such as electrons, consistent with both the principles of quantum mechanics and the theory of special relativity.
		In the Dirac representation, the equation for ψ
		This is the basis for the use of the Dirac equation in quantum field theory.
	en.wikipedia.org /wiki/Dirac_equation (2936 words)

	The Dirac Prediction g=2 (Site not responding. Last check: 2007-10-10)
		The Dirac equation is a set of coupled differential equations among the four component fields in the Dirac spinor[143]:
		Indeed, the mixing of the Dirac field components is characteristic of the spin 1/2 representation of the Lorentz group.
		To return to diagonalization, the Dirac equation can be decoupled into independent equations, one for each of the components of the Dirac field spinor, by means of a Foldy-Wouthysen (unitary) transformation [144].
	hep.bu.edu /~brown/phd/node82.html (486 words)

	Unified Physics-Mathematics
		The wave function depends on the sum of the squares of E- and H-fields as is seen by examining the energy density function of the electromagnetic field.
		Dirac's equations were described in terms of two 'fields', the so-called Dirac fields, and were described as 'field equations of motion'.
		In SFT, the term 'spinor' is used for the motions of the E- and H-fields, and for the motions of the particles, such as the electron or proton.
	www.unifiedphysics.com /mathematics.htm (2291 words)

	Twistors and/or spinors - Advanced Physics Forums (Site not responding. Last check: 2007-10-10)
		Spinors are a kind of mathematical object used when working with fermions (particles of spin-1/2).
		A typical (Dirac) spinor has four components, which roughly correspond to a spin-up particle, a spin-down particle, a spin-up antiparticle and a spin-down antiparticle.
		Working with spinors is more difficult than working with scalars or vectors because you need an extra set of matrices that allow you to work with the four components of the spinor.
	www.advancedphysics.org /forum/showthread.php?t=479 (511 words)

	[No title]
		An n-dimensional spinor is an element of a specific projective representation of the rotation group SO(n, R), or more generally SO(p, q, R), where p + q = n for spinors in a space of nontrivial signature.
		The most common type of spinor is the Dirac spinor which is a member of the fundamental representation of the complexified Clifford algebra C(p, q), into which Spin(p, q) can be embedded.
		Type IIA and Type IIB superstring theory have a vector x spinor and spinor x vector which are the gauge fields for the local supersymmetry.
	www.geocities.com /jefferywinkler/beyondstandardmodel9.html (3356 words)

	Dirac
		Dirac demonstrates the “Dirac belt trick”, whereby two full twists in a belt are removed while keeping the ends fixed.
		For clarity, bending of the belt (as opposed to transverse twisting) is not included in the rotations shown in the inset.
		Also, the initial orientation of the belt is taken to lie on the border of the sphere of rotations, rather than at the centre; this just amounts to a convenient choice of reference frame, and makes no difference to any of the topology.
	gregegan.customer.netspace.net.au /APPLETS/21/21.html (313 words)

	[No title]
		Quantum theory as formulated before Dirac was inconsistent with special relativity.
		Dirac discovered a wave equation that is not only consistent with relativity but also explains particle spin, predicts the existence of antiparticles, and provides us with a deep insight into such symmetries of nature as spatial inversion (parity), charge conjugation and time reversal.
		Lorentz and Rotational Covariance of the Dirac equation
	newton.ex.ac.uk /handbook/00-01/modules/PHY4404.html (626 words)

	Isovector dipole excitations in the relativistic RPA
		In the present analysis we want to explore to what extent the random phase approximation in the relativistic mean field theory can answer the question of collectivity in the low-lying isovector dipole excitations.
		When considering isovector dipole modes, the contributions from Dirac states do not contribute significantly, in contrast to the large effect to the RRPA strength distributions in the isoscalar case, where contribution of scalar
		Pb is shown in the Fig.1, separately for calculations without and with Dirac states contributions due to exchange of scalar and vector mesons.
	www.phy.hr /~npaar/pygmy/node2.html (619 words)

	Sympathetic Vibratory Physics - John W. Keely's Sacred Science.
		A vector with two complex components, which undergoes a unitary unimodular transformation when the three-dimensional coordinate system is rotated; it can represent the spin state of a particle spin 1/2.
		More generally, a spinor of order (or rank) n is an object with 2n components which transform as products of components of n spinors of rank one.
		A quantity with four components which transform in such a way that if it is a solution of the Dirac equation in the original Lorentz frame it remains a solution of the Dirac equation in the transform frame; it is formed from two spinors (definition 1).
	www.svpvril.com /svpnotes/SPINOR_58611.html (112 words)

	Clifford Algebra
		A Dirac algebra spinor has twice as many degrees of freedom and can represent any of four cases for the particle, spin up or down electron and spin up or down positron.
		This will expand the Dirac spinor from just dealing with an electron or neutrino to covering both cases.
		With the Dirac algebra, there are 16 complex degrees of freedom (or 32 real degrees), so multiplying two elements of the algebra involves 1024 multiplications and about that many additions.
	www.cliffordalgebra.com (404 words)

	Dirac spinor Algebra (Site not responding. Last check: 2007-10-10)
		All linear terms will vanish upon the symmetric integration interval d from ; the term will not contribute to and hence is a Dirac form factor term.
		Using the Dirac matrix identity three times per term to write these in terms of and :
		In the last line use has been made of the Dirac equation and which renders the first column above as terms which as column 2 above are dropped since they contribute to.
	hep.bu.edu /~brown/phd/node89.html (131 words)

	[No title]
		This doesn't happen in the relativistic case because elements of D (spinors) are not left unchanged by the action of the Lorentz group.
		The momentum space Dirac equation is gamma^mu p_mu f(p) = m f(p), which in the electron's rest frame becomes gamma^0 f(m,0,0,0) = f(m,0,0,0), since then p = (m,0,0,0).
		The Dirac equation then gives c = a and d = b, and consequently the space of all possible f(m,0,0,0) is a 2-dimensional subspace of spinor space D. 4-component Dirac spinors are needed to implement parity transformations, and the Dirac equation serves to project out unnecessary degrees of freedom.
	www.math.niu.edu /~rusin/known-math/01_incoming/QFT (2052 words)

	rp56-02 (Site not responding. Last check: 2007-10-10)
		Almost all presentations of Dirac theory in first or second quantization in Physics (and Mathematics) textbooks make use of covariant Dirac spinor fields.
		There, a new concept of spinor field (as a sum of non homogeneous even multivectors fields) is used.
		The necessity of our definitions are shown by a carefull analysis of possible formulations of Dirac theory and the meaning of the set of Fierz identities associated with the `bilinear covariants' (on Minkowski spacetime) made with ASF or DHSF.
	www.ime.unicamp.br /rel_pesq/2002/rp56-02.html (268 words)

	Bohm Compton Radius Vortex Sidharth Sarfatti
		A self consistent solution to Dirac equation in a Kerr Newman space-time with M^2 > a^2 + Q^2 is presented for the case when the Dirac particle is the source of the curvature and the electromagnetic field.
		The ordinary free particle solutions of the Dirac equation are completely delocalised; the curvature however, now causes the Dirac wave functions to be localised over a region comparable in dimension to the Compton wavelength of the particle.
		In Unruh's case of a wedge region or in the analogous case of conformal matter enclosed in a double cone, the hidden quantum symmetry passes to the one described by a Killing vector associated with the Lorentz or conformal- group.
	www.valdostamuseum.org /hamsmith/Sidharth.html (5379 words)

	Dirac Spinors and Degrees of Freedom
		Dirac equation for a non-zero mass projects two degrees of freedom out
		Weyl spinors, one L and one R, each with one degree of freedom, and have
		R to denote left and right-handed chirality spinors.
	www.physicsforums.com /showthread.php?t=127992 (3246 words)

	spinor - OneLook Dictionary Search
		Tip: Click on the first link on a line below to go directly to a page where "spinor" is defined.
		Spinor : Eric Weisstein's World of Mathematics [home, info]
		Phrases that include spinor: dirac spinor, majorana-weyl spinor, majorana spinor, spinor group, weyl-majorana spinor, more...
	www.onelook.com /?w=spinor (101 words)

	Fields and Particles Bookmarks
		Clifford Algebraic Spinor and the Dirac Wave Equations Eprints
		The Lorentz Dirac Equation and the Structures of Spacetime Eprint
		On the Universal Quantum-Gravitation Equation and Dirac Hypothesis Diss
	www.geocities.com /diahmed/bookmark2.html (2853 words)

	diraceq (Site not responding. Last check: 2007-10-10)
		In addition its development from a simple Newtonian formula for kinetic energy meant that it was relativistically incorrect.
		Paul Dirac solved both of these problems by replacing the wavefunction with a four component object
		This meant that there were four possible 'varieties ' for the electron.
	www.egglescliffe.org.uk /physics/equations/diraceq/diraceq.html (81 words)

	Dirac adjoint - Wikipedia, the free encyclopedia
		The Dirac adjoint is motivated by the need to form well-behaved, measurable quantities out of Dirac spinors.
		One source of trouble is that if λ is the spinor representation of a Lorentz transformation, so that
		Using the Dirac adjoint, the probability density for a spin-1/2 particle field can be written as
	en.wikipedia.org /wiki/Dirac_adjoint (149 words)

	Relativistic Theory of the Non-Symmetric Field
		This is recent work in much the same area as yours, and\nI\'m disappointed that you have not put in references.
		This has got to be essential for\na theory of everything, but, as Uncle Al states correctly, you\nare never going to get a Dirac spinor appearing as part of a\nKaluza-Klein-type theory as they stand.\n\nI note that you are relaxing Einstein\'s condition of symmetry of\nthe metric tensor.
		The\nRicci curvature tensor does not explicitly involve the metric\ntensor, and equating it to zero gives you equations which are not\ntotally dissimilar to the Dirac and/or Maxwell equations.
	www.physicsforums.com /showthread.php?t=78611 (1891 words)

	Spinor - Wikipedia, the free encyclopedia
		which implies that the single spinor representation is 4-dimensional and pseudoreal.
		For example, in 3+1 dimensions there are two non-equivalent Weyl complex (like in 2 dimensions) 2-component (like in 4 dimensions) spinors, which follows from the isomorphism
		^ Dirac, P., "The quantum theory of the electron", Proceedings of the Royal Society of London Series A, Retrieved from "http://en.wikipedia.org/wiki/Spinor"
	en.wikipedia.org /wiki/Spinor (4188 words)

	Approximations: Atomic Ref. Data Elect. Struct. Calculations
		The functions G(r) and F(r) are related to the Dirac spinor by
		where µ runs over the four components of the Dirac spinor.
		The inclusion of relativistic effects doubles the number of degrees of freedom in atomic calculations.
	physics.nist.gov /PhysRefData/DFTdata/approx.html (530 words)

	Free Motion of a Dirac Particle
		This is the four dimensional generalization of the spin vector operator.
		Helicity is the projection of the spin onto the direction of the momentum.
		This implies that a negative-energy solution with spin down is equivalent to a positive-energy solution with spin up.
	www.phys.ualberta.ca /~gingrich/phys512/latex2html/node48.html (202 words)

	Problem Set 3
		Consider a theory of a free Dirac field of mass
		Solve for the lower two components of the Dirac spinor
		Would knowing the exact solution to the Dirac equation in a background Coulomb field improve the accuracy of the predicted energy levels?
	courses.washington.edu /ph520/570/ps3 (652 words)

	wilson.h File Reference
		Go to the source code of this file.
		Number of floating-point numbers in half a Dirac spinor.
		Number of floating-point numbers in a Dirac spinor.
	qcdoc.phys.columbia.edu /doxygen/ref/wilson_8h.html (150 words)

Try your search on: Qwika (all wikis)