Aspect ratio (image): Difference between revisions

From formulasearchengine
Jump to navigation Jump to search
en>Dutchmonkey9000
→‎Previous and currently used aspect ratios: Bolding for better legibility
→‎Previous and currently used aspect ratios: Removed uncited "planned futuristic aspect ratio". Corrected 16mm listing. Removed a redundancy with the 2.76:1 ratio listing, and the 2.76:1 listing.
 
(One intermediate revision by one other user not shown)
Line 1: Line 1:
The '''Schrödinger group''' is the [[symmetry group]] of the free particle [[Schrödinger equation]].
Sabine is what you can call her but she never truly liked that title. Interviewing has been my working day occupation for a whilst and it's some thing I really enjoy. Maine is her beginning location but her husband wants them to move. The thing he adores most is gardening and he'll be beginning some thing else along with it. I've been working on my web site for some time now. Check it out right here: [http://www.news10.com/story/26808621/forskolin-review-does-all-natural-forskolin-really-work-read-my-honest-forskolin-review http://www.news10.com]/story/26808621/forskolin-review-does-all-natural-forskolin-really-work-read-my-honest-forskolin-review
 
==Schrödinger algebra==
 
The Schrödinger algebra is the [[Lie algebra]] of the Schrödinger group.
 
It contains [[Galilean transformation|Galilei algebra]] with central extension.
 
:<math>[J_i,J_j]=i \epsilon_{ijk} J_k,\,\!</math>
:<math>[J_i,P_j]=i \epsilon_{ijk} P_k,\,\!</math>
:<math>[J_i,K_j]=i \epsilon_{ijk} K_k,\,\!</math>
:<math>[P_i,P_j]=0, [K_i,K_j]=0, [K_i,P_j]=i \delta_{ij} M,\,\!</math>
:<math>[H,J_i]=0, [H,P_i]=0, [H,K_i]=i P_i.\,\!</math>
 
Where ''J_i'', ''P_i'', ''K_i'', ''H'' are generators of rotations ([[angular momentum operator]]), spatial translations ([[momentum operator]]), Galilean boosts and time translation ([[Hamiltonian mechanics#Mathematical formalism|Hamiltonian]]) correspondingly. [[Central extension (mathematics)|Central extension]] ''M'' has interpretation as non-relativistic [[mass]] and corresponds to the symmetry of [[Schrödinger equation]] under phase transformation (and to the conservation of probability).
 
There are two more generators which we will denote by ''D'' and ''C''. They have the following commutation relations:
 
:<math>[H,C]=i D, [C,D]=-2i C, [H,D]=2i H,\,\!</math>
:<math>[P_i,D]=i P_i, [K_i,D]=-iK_i,\,\!</math>
:<math>[P_i,C]=-iK_i,[K_i,C]=0,\,\!</math>
:<math>[J_i,C]=[J_i,D]=0.\,\!</math>
 
The generators ''H'', ''C'' and ''D'' form the sl(2,R) algebra.
 
==The role of the Schrödinger group in mathematical physics==
 
Though the Schrödinger group is defined as symmetry group of the free particle [[Schrödinger equation]], it is realised in some interacting non-relativistic systems (for example cold atoms at criticality).
 
The Schrödinger group in d spatial dimensions can be embedded into relativistic [[conformal group]] in d+1 dimensions SO(2,d+2). This embedding is connected with the fact that one can get the [[Schrödinger equation]] from the massless [[Klein-Gordon equation]] through [[Kaluza-Klein theory|Kaluza-Klein compactification]] along null-like dimensions and Bargmann lift of [[Newton-Cartan theory]].
 
== References ==
 
* C. R. Hagen, Scale and Conformal Transformations in Galilean-Covariant Field Theory, Phys. Rev. D 5, 377–388 (1972)
* Arjun Bagchi, Rajesh Gopakumar, Galilean Conformal Algebras and AdS/CFT, JHEP 0907:037,2009
* D.T.Son, Toward an AdS/cold atoms correspondence: A geometric realization of the Schrödinger symmetry, Phys. Rev. D 78, 046003 (2008)
 
==See also==
 
*[[Schrödinger equation]]
*[[Galilean transformation]]
*[[Poincaré group]]
 
{{DEFAULTSORT:Schrodinger group}}
[[Category:Theoretical physics]]
[[Category:Quantum mechanics]]
[[Category:Lie groups]]

Latest revision as of 01:14, 18 December 2014

Sabine is what you can call her but she never truly liked that title. Interviewing has been my working day occupation for a whilst and it's some thing I really enjoy. Maine is her beginning location but her husband wants them to move. The thing he adores most is gardening and he'll be beginning some thing else along with it. I've been working on my web site for some time now. Check it out right here: http://www.news10.com/story/26808621/forskolin-review-does-all-natural-forskolin-really-work-read-my-honest-forskolin-review