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THEROLEOFORTHOGONALAND SYMPLECTICCLIFFORDALGEBRAS INQUANTUMTHEORY

MatejPavšič J.Stefan Institute,Ljubljana,Slovenia

Contents

- Introduction - Spaceswithorthogonalandsymplectic forms - Heisenbergequationsasequationofmotionforvectors - Pointparticlein`’ Descriptionoffields Orthogonalcase Symplectic case Discussion:Prospectsforquantumgravity - Conclusion Introduction

Persisting problem of quantum gravity and the unification of interactions. Aneedtoreformulatetheconceptualfoundationsofphysicsandtoemployamore evolvedmathematicalformalism.

InthistalkIwillconsiderCliffordalgebraswhichprovideverypromisingtools fordescriptionandgeneralizationofandphysics.

Orthogonal Clifford algebra

Theinner, symmetric ,productofbasisvectors 1 γ a givesthe orthogonal metric,. γ a γ· γ γ γ γb≡2 ( ab + ba ) = g ab gab 1 Theouter, antisymmetric ,productofbasisvectors γ γ a∧ γ γ γ γ b ≡2 ( ab − b a ) givesthebasis.

Symplectic Clifford algebra Theinner, antisymmetric ,productofbasisvectors q 1 a givesthe symplectic metric,.J ab qab∧q ≡2 ( q ab qqq− b a ) = J ab 1 Theouter, symmetric ,productofbasisvectors qab·q ≡ 2 (q ab qqq+ b a ) givesasymplectic bivector. Thegeneratorsofan orthogonalClifford algebracanbetransformedintoabasis inwhichtheybehaveas fermionic creationandannihilationoperators. Thegeneratorsofa symplectic Cliffordalgebrabehave as bosonic creationandannihilationoperators. Wewillshowhowbothkindsofoperatorscanbeunitedintoasingle structuresothattheyformabasisofa`superspace’. Wewillconsideranactionforapointparticleinsuchsuperspace.

Insteadoffinitedimensionalspaces,wecanconsiderinfinitedimensionalspaces. Thenwehavedescriptionofafieldtheoryintermsoffermionic andbosonic creationandannihilationoperators. Thelatteroperatorscanbeconsideredasbeingrelatedtothebasisvectors ofthecorrespondinginfinitedimensionalspace. Spaces with orthogonal an symplectic forms

I. Orthogonal case (,)ab= ( γ γabab γ γ , ) = a a (,) bagb bab = g a bg abg ab a= a γ

(γ γa , b ) g= g ab metric

Forabasiswecantakegeneratorsofthe Basisvectors orthogonalCliffordalgebra: 1 γ γ γ γ γ (,)γ γ =g = ( + ) =· = g abg ab2 ab ba a b ab Vectorsare Cliffordnumbers: 1 (,)a b= ( ab + ba ) = a ·b g 2

Innerproductofvectors a and b II. Symplectic case

ab a bab (,')(zzJ = zqza ,')q bJ = zqqz (,)' a b J = zJzab ' a z= z q a symplectic metric (qa , q b ) J = J ab

Symplectic basisvectors Forasymplectic basiswecantakegeneratorsofthe symplectic Cliffordalgebra: 1 (,)qq= J = ( qq −q q ) = q ∧ q = J a b J ab2 ab b a a b a b Vectorsarenowsymplectic Cliffordnumbers: 1 (,')zz= ( zzzz '− ') = z ∧ z ' J 2

Innerproductofsymplectic vectors z and z’ Explicit notation with coordinates and momenta za = ( x , p ) a ()x () p Symplectic vector z= zqa = xq + pq

a b a 1 b (,')zzJ= zqq (,)ab J z ' = z 2 (q abbaq− qq) z ' a b = z Jab z ' 0 ην  ν ν ν J = =(xp ' − px ') ην ab   −ην 0 

1 Relations give 2 [qa , q b ] = J ab

1()()xx 1 ()( pp ) ν 2[qq ν , ]0,= 2 [ qq , ]0 = 1 (x )( p ) Heisenbergcommutation 2 [ νq ν , q ] =η relations Poisson bracket (symplectic case) ∂f ∂ g {f , g } ≡ J ab PB ∂za ∂ z b Byintroducingthesymplectic basisvectors, wecanrewritetheaboveexpressionas Symplectic metric

1 ∂fa ∂ g b ∂fab ∂ g [a q, b q ] = aJ b 0 −ην  2 ∂zz∂ ∂ z ∂ z J ab =   ην 0  c d Ifwetake fz=, gz =

0 ην  1 c d cd J ab =   [q , q ] = J −ην 0  2

ThesearetheHeisenbergcommutation c d relationsfor`operators’and.q q

a a a q arethus`quantized’phasespacecoordinates z . z arerealcoordinates Poisson bracket (orthogonal case) ∂f ∂ g {f , g } ≡ g ab PB ∂ λλ a ∂ b Byintroducingthebasisvectors wecanrewritetheaboveexpressionas Orthogonalmetric

1 ∂fa ∂ g b  ∂f a b ∂ g  γγ ,  = g η ν 0  2  ∂ λλ a∂b  ∂ λλ a ∂ b g ab = ν  0 η  c d Ifwetake f λ=λ , g =

ην 0  1cd 1 cd dc cd gab =   {γ γ γ γ , γγ } ≡ (+ ) = g 0 ην  2 2

Thesearetheanticommutation relationsfor c d `operators’and.γ γ

a a a γ arethus`quantized’.λ λ arerealanticommuting coordinates Representation of operators

I.OrthogonalCliffordalgebra η 0 1 ν  gab =   γ γ γγ γab·≡ ( ab + ba ) = g ab 2 0 ην  Inevendimensionswecanwrite:

γ γ γ a =( , ), = 0,1,2,3 WecanintroduceWittbasis: 1 γ γ θ = (+ i ) 2 1 γ γ θ = (− i ) 2 1 θθ θ θ θ θ θ η θ ·= ( += ),·0,·0 = = νν ν ν ν ν ν ν 2

γ ,γ , θ , θ canberepresented: 1)as4x4matrices, 2)intermsofGrassmann coordinates: ν ∂ θ ξ θ →2 , → 2 θ η θ = ν ∂ξ ξ ξ ν ξ ν + = 0 II.Symplectic Cliffordalgebra 1 qa∧≡ q b( qqqq ab − ba ) = J ab 0 ην  2 J ab =   −ην 0  Wecanwrite: ()x () p qa =( q , q ), = 0,1,2,3

1 q()x∧ q () p= (q ()() xp q − q ()() pxq ) =η ν ν ν 2 ν ()xx () () pp () q ν∧ qν = 0,q ∧ q = 0 Thentheoperatorscannot ()x () p canberepresented: becastintoHermitian form q , q 1)as4x4matrices, 2)intermsofcommutingcoordinates:

()x () p ∂ (x) ν (x ) q →2x , q → 2 q=η q ∂x ν xx ν ν − xx = 0 Heisenberg equations as equations of motion for basis vectors Letusnowconsidertheaction za = ( x , p ) I=1 dzJzτ (ɺa b + zKz a b ) H= 1 zKza b 2 ∫ ab ab 2 ab δ za ∂H zɺa= J ab ∂zb

a Letusconsidertrajectoriesascomponez (τ ) ntsofan infinitedimensionalvector: τq τ a()τ ∧ q b (') = J ab ()(') zzq= a(τ ) ≡ dz τ τ τ a () q () a(τ ) ∫ a =J ab δ τ τ( − ′ ) τ ɺa()τ a () ɺ zq τ a()τ = − zq a () andwritetheactionintheform τ τ 1 τ a()τ ba (') 1 () b (') H 1 a b ɺ = 2 τdz τ τ () Kzab () IzJ=2 τ ab()(') τ z + 2 zK ab ()(') z ∫ 1 τ a(τ ) b ( ') = z Ka( τ ) b ( ') z Theequationsofmotionare: 2 K= K δ τ τ( − ′ ) ∂H ab( τ ) ( ') ab τ τ τ τ zqɺa()τ =− zqqJ a ()ɺ = ab ()(') =− qKz a () b (') τ τ a()()()τ a a ∂zb(τ ') a( τ ) b ( ') a(τ ) a τ τ b(τ ')ɺ a ( ) b ( ') q≡ q (τ ) zq τ b(τ ')= qK a ( ) b ( ') z

b(τ ) Thisequationholdsforany z ɺ a(τ ) τqb(τ ')= q K a ( ) b ( ') Equationsofmotion foroperators qa(τ )

Kab( τ ) ( ') = K ab δ τ τ( − ′ )

ɺ a Kab= K ba qb τ()τ = q () K ab ˆ 1 a b H= 2 qKqab Symplectic innerproduct ˆ b [qHa , ] = Kq ab isgivenby ɺ ˆ qa= [ q a , H ] Heisenbergequations ofmotion

Weseethatthebasisvectorsofphasespace satisfytheHeisenbergequationsofmotionfor `quantum’operators qa(τ ) ≡ q a (τ ) τ τ b(τ ') a ( ) b ( ') ɺ a(τ ) a zq τ b(τ ')= qK a ( ) b ( ') z z≡ z (τ )

b(τ ) Thisequationholdforany z ɺ a(τ ) τqb(τ ')= q K a ( ) b ( ') Equationsofmotion foroperators qa(τ ) K= K δ τ τ( − ′ ) ab( τ ) ( ') ab a(τ ) Thattheoperatorequationsholdforanyz means ɺ a thatcoordinatesandmomenta areundetermined.Kab= K ba qb τ()τ = q () K ab ˆ 1 a b H= 2 qKqab b Symplectic innerproduct [qH ,ˆ ] = Kqa az τ τ ab()τ = ( x (), p ())isgivenbycommutator ɺ ˆ qa= [ q a , H ] Heisenbergequations ofmotion

Weseethatthebasisvectorsofphasespace satisfytheHeisenbergequationsofmotionforClassicalsolution Anytrajectory `quantum’operators Point particle action in `superspace’

Weintroducethegeneralizedvectorspace whoseelementsare: A a a a a A z= ( z ,λ ), z= ( x , x ) , λλ λ = ( , ) Z= z q A qA= (qa ,γ a ), qa = (q , q ), γγ a = ( ,γ )

coordinates basiselements symplectic orthogonal part J ab 0  part 〈qAq B 〉= S G AB =   0 gab   0 ην  qa ∧ qb = J ab =   symplectic metric  −ην 0 

ην 0  γ a ·γ b =gab =   orthogonalmetric  0 ην  Letusconsideraparticlemoving insuchspace.Itsworldline isgivenby: zA= Z A (τ )

parameterontheworldline ) Exampleofapossibleaction Exampleofapossibleaction za = ( z , z ) 1A B 1 A B J abɺ0  A a. ɺ a I= τ d τ 〈ZqZAqB 〉 S = d ZGZ AB 2∫GAB =  , 2 ∫ z = (,) z λ a a bɺ a0 ɺ g a λλ λ = ( , ) I= dτ ( zJzɺ ɺ + λ  g λ )ab  ∫ ab ab J 0  = 0,1,2,3 G=ab , zA = (,) z a. λ a J= − J AB g  = g Since,ab ba Since,0 gab ab  ba thistermdiffers thistermdiffers fromzeroif fromzeroif J= − J areGrassmann1 aɺ b aarecommutingɺ b ab ba I=2 d τ (zJzab + λ g ab ) coordinates.∫ coordinates. gab= g ba

Inthisterm,za Inthisterm, λ a arecommuting areanticommuting coordinates. (Grassmann)coordinates.

Canonicalmomenta: ∂L p( z) = = 1 J zb , a∂zɺa 2 ab

(λ ) ∂L 1 a pa=ɺa = 2 g a bλ ∂λ I=1 d τ (zJzaɺ b + λ a g ɺ b ) 2 ∫ ab ab

0 ην  ην 0  J ab =   , gab =    −ην 0   0 ην  ɺ I=1 d ητ ( xɺ ν ν ν x ν − xɺ λη η λ λ η λ x +ɺ + ) 2 ∫ ν νν ν

ν ν x , x arecommuting [xx , ]= 0,[ xx , ] = 0 λ λ , areGrassmannian νλ { λλ λ ν , }0,{= , }0 =

Canonicalmomenta: ∂L ∂ L p()x == η 1 η xpν , ()x ==− 1 x ν ∂xɺ 2 ν ∂ xɺ 2 ν

(λ )∂L1 ν (λ ) ∂ L 1 ν p ==ɺ ν η λ 2 η λ ν , p == ɺ 2 ∂λ ∂λ Quantization ()x () x Operators xp, → xpˆ , ˆ λ λ λ λ ,p()→ ˆ , pˆ () Similarrelationshold where (x ) forbarredquantities.. [,]xˆ ν p ˆ ν = i δ , ν ()x () x [,]0,[xxˆˆ= pp ˆˆ ν , ]0 =

λ ˆ λ ()ˆ () δ λ δ ν{,λ ν ν piˆν }= ,{, pi ˆ } = λ λ ˆ ν ˆ () () {,}0,λ λ = {pˆ ν , p ˆ }0 = a Altogether,wehave z= ( z , z ) a( z) a( z ) a zp,a→ zpˆ , ˆ a λλ λ = ( , ) a λ (λ ) ˆ a ( ) λλ ,pa→ , pˆ a = 0,1,2,3 wheretheoperatorssatisfy

a( z ) a [zˆ , pˆb] = i δ b ˆa(λ ) a {λ , pˆb } = i δ b Anticommutators a( z ) a [zˆ , pˆb ] = i δ b ˆa(λ ) a δ{λ ,pˆb } = i b (z ) 1 b pa= 2 J ab z , (λ ) 1 a pa= 2 g ab λ 1 a b ab 2 [zˆ , z ˆ ] = iJ 1 ˆa ˆ b ab 2 {λ λ , } = i g

Butweseethattheaboveoperatorequationsarejust therelationsforthebasisvectorsoftheorthogonal andsymplectic Cliffordalgebra,providedthatwe identify: zˆa = ( q , iq ) γλ ˆa = ( ,i )

Wesethat`quantization’isinfactthereplacements a a ofthecoordinateswiththecorrespondiz , λ ng basisvectors. Theonlydifferenceisin thefactor i infrontof q 1 a b aɺ b I= d τ (zJzɺ + λ g λ ) 2 ∫ ab ab 1 a baɺ b =dτ 〈 z q q zɺ +λ γ λγ 〉 qa = ( q , q ), 2 ∫ ab ab S γ γγ a = ( , )

Basisvectors,enteringtheaction,are`quantumoperators’, apartfromthe i intherelations zˆa =( q ,i q ), γ γ λ ˆa = ( , i ) qa = ( q , q ), 1 a b aɺ b I= d τ (zJzɺ + λ g ) 2 ∫ ab ab γ γγ a = ( , ) =〈1 dτ za q q zɺ ba +λ γ γ λ ɺ b 〉 2 ∫ ab ab S λ λ ξ λ λλ ′a = (,), ′′ ′ ≡=−1 (i ) 1 a b a ɺ b 2 = λ dτ (zJzɺ + λ′ g ′ ′ ) 2 ∫ ab ab ′ 1 λ λ ξ λ ≡ =2 ( + i ) 0 η ν ɺ ɺν ν  ξ ξ η η ξ + g '=γ γ′ · ′ = ν ν ab a b   ην 0  Theaboveactionisnotcomplete.Anadditionaltermisneeded.

I= 1 dZGZτ Aɺ B J 0  2 ∫ AB G = ab AB 0 g  ɺ B ɺ B B C replacewithcovariantderivative ab  ZA→Z + C Z I=1 dZGτ A( Zɺ B + AZ BC ) GeneralizedBarsaction 2 ∫ AB C (invariantunderdependentτ rotationsof)Z A Inparticular,thistermgives: Masscomesfrom βα λ p p+ p extradimensions

A Lagrangemultipliers(containedin)A C Uponquantization,theclassicalconstraint λ p = 0 becomesthe:

ˆ λ pˆ Ψ = 0 where.λ γˆ =

Ψ canberepresented α 1) asacolumn ψ 2)asafunction ψ ξ (x , )

λ γˆ = canberepresented 1)asmatrices ∂ 2)as ξ + ∂ξ Wealsohavewhichcanbereprese γλ ˆ = i nted 1)asmatrices ∂ 2)as i(ξ − ) ∂ξ 1 1 θ η θ ·≡ {,} = , From γ γ θ =( + i ) ν ν ν 2 2 1 θ θθ θ ·= 0, · = 0 γ γ θ (i ) ν ν =2 − wecanbuildup bytakinga `vacuum’

= ∏θ whichsatisfies θ = 0 = 0,1,2,3 andactingonitby`creation’operators.θ Soweobtaina`Fock space’basisforspinors: ɶ θ θ θ θ ϑ Aɶ =(1 , νρ νρσ ν , , , ) A = 1,2,...,16

intermsofwhichanystatecanbeexpanded:

Aɶ Ψ = ψ ϑ ɶ ∑ A

Withoperatorsdefinedabove,wecancθ θ , onstructthe spinors astheelementsofaminimalleftof.Cℓ(8) =1 ( − i ) λ λ ξ 2 Takingallpossiblevacua,suchas λ λ ξ =1 ( + i ) =θ θ θ θ ...... ,r = 0,1,2,3,4 2 12rr+ 12 r + n weobtaintheFock spacebasisforthewholeCl (8). Description of fields Orthogonalcase

Ψ = ψ i( x ) h ℝ3 ℝ 1,3 i(x ) i=1,2; x ∈ or x ∈ particularcase h· h = ρ ix( ) jx ( ') i(x ) j ( x ') metric δ δρ i( x ) j ( x ') = ij (x − x ')

Newbasis: 1 h()x=2 ( h 1() x + ih 2() x ) Wittbasis 1 h*(x )=2 ( h 1( x ) − ih 2( x ) ) δρ ≡(x − x ') (x ) *( x ) (x )*( x ') h(x )· h *( x ')= ρ ( xx )*( ') Ψ = ψψ h(x ) + h *(x ) ρρ (xx )*( ')= *( xx ) ( ') hh(xx )· ( ')= h *( x ) · h *( x ') = 0 Fermionic commutation Scalarproduct: relations (x ) *( xx ') *( ) ( x ') 〈ΨΨ〉=Sψ ψ ψ ρ ( xx )*( ') + *( xx ) ( ')

(x ) ψ h(x ) →| Ψ〉 Bothvectorsbringthesame *(x ) informationaboutthestate ψψ h*(x ) → 〈 |

〈ΨΨ〉=| ψ ψ ψ ψ ρ ψ *(x )hh · ( xx ') = *( ) ( x ') = dxxx * ()() *(xx ) ( ') *( xx )( ') ∫ Vacuum h = 0 = ∏ h*(x ) *(x ) x (x ) Thesecondpartofdisappears Ψ=ψ h (x ) Ψ (x ) *( x ) Ψ = ψψ h(x ) + h *( x )

Letusconsideramoregeneralcase:

()x ()(') x x Ψ=+( ψψ ψ 0h ()x + h ()(') x h x + ... ) Thisstateistheinfinitedimensionalspaceanalog ofthe asanelementofaleftidealof Cliffordalgebra

Reversedstate:

‡ ‡† ‡ * *()x *()(') x x ()Ψ=Ψ= ψ (ψ ψ 0 + h *()x + h *()*(') x h x + ...) Then (Ψ ) ‡ Ψ= ‡ Ψ ‡ Ψ ‡ *(x ) ( x ') ‡ *( xx ) ( ') ψ ψ δ = ψ ψ h*(x ) h ( x ') +=... 2 (x ) ( x ') + ...

2δ(xx )( ')− h ( x ') h *( x ) Thisactingon vacuumgives0 Vacuum h = 0 = ∏ h*(x ) *(x ) x (x ) Thesecondpartofdisappears Ψ=ψ h (x ) Ψ (x ) *( x ) Ψ = ψψ h(x ) + h *( x )

Letusconsideramoregeneralcase:

()x ()(') x x Ψ=+( ψψ ψ 0h ()x + h ()(') x h x + ... ) Thisstateistheinfinitedimensionalspaceanalog ofthespinor asanelementofaleftidealof Cliffordalgebra

Weobtainanonvanishingformiswetakethe reversedstate ‡ ‡ *(x ) ( x ') 〈 ΨΨ〉S =ψ ψ δ ( x ) ( x ') + ... ‡ ‡‡ ‡ * *()x *()(') x x ()Ψ=Ψ= ψ (ψ ψ 0 + h *()x + h *()*(') x h x + ...) scalarpart Then (Ψ ) ‡ Ψ= ‡ Ψ ‡ Ψ ‡ *(x ) ( x ') ‡ *( xx ) ( ') ψ ψ δ = ψ ψ h*(x ) h ( x ') +=... 2 (x ) ( x ') + ...

2δ(xx )( ')− h ( x ') h *( x ) Thisactingon vacuumgives0 Symplectic case

3 * ɺ x ∈ℝ Schroedinger field I= ∫ τ d φ τ d x i (, φτ x ) (, x ) − H  x ∈ℝ1,3 ∂L * Stueckelberg field ɺ = Π = iφ ∂φ I τ= dτ dx φ φ Πφ ɺ −H  = d d x 1 ( Π ɺ −Π−ɺ ) H  ∫  ∫  2 

φφ ix()= ( () x ,Π () x ) , i = 1,2

ɺix( ) jx ( ') 0 δ(x )( x ')  IdJ= φτ φ (i( x ) j ( x ') − H ) J = ∫ i( x ) j ( x ')   −δ(x )( x ') 0  Symplectic vector: ix() 1() x 2() x δδ ≡(x − x ') Φ = φφ kix()=k 1() x + φ k 2() x (x )( x ') ≡φ ()xk + Π () x k φ()xΠ () x Symplectic innerproduct: Bosonic commutationrelations kix()∧ k j(x ') = J ijx ()(') x

basisvectors metric Symplectic case

3 * ɺ x ∈ℝ Schroedinger orscalarfield I= ∫ τ d φ τ d x i (, φτ x ) (, x ) − H  x ∈ℝ1,3 ∂L * Stueckelberg field ɺ = Π = iφ ∂φ I τ= dτ dx φ φ Πφ ɺ −H  = d d x 1 ( Π ɺ −Π−ɺ ) H  ∫  ∫  2 

φφ ix()= ( () x ,Π () x ) , i = 1,2

ɺix( ) jx ( ') 0 δ(x )( x ')  IdJ= φτ φ (i( x ) j ( x ') − H ) J = ∫ i( x ) j ( x ')   −δ(x )( x ') 0  Symplectic vector: ix() 1() x 2() x H φ= φ ix( ) K jx ( ') δδ ≡(x − x ') Φ = φφ kix()=k 1() x + φ k 2() x i( x ) j ( x ') (x )( x ') ≡φ ()xk + Π () x k φ()xΠ () x 1 r  Ki( x ) j ( x ') = −∂ ∂r + V( x )  δ ( xxg − ') ij , Symplectic innerproduct: 2m  0 1  kix()∧ k j(x ') = J ijx ()(') x gij =   1 0  2 r basisvectors metric (m + ∂ ∂r )δ (x − x ') 0  Ki( x ) j (x ') =   , 0δ (x− x ' )  Poissonbracket ∂f ∂ g 0 − δ ix() ix () ixjx () (' ) i( x ) j ( x ') (x )( x ')  {}f φ(φ ),( g ) = ix() J jx (' ) J = PB ∂φ ∂ φ   δ(x )( x ') 0  Inparticular: f φ=φ kx( ''), g = lx ( ''')

{ φφ kx( ''), lx ( ''')} =J kxlx ( '') ( ''')= k kx ( '') ∧ k l(x ''') PB ≡ 1 kk (x '') , k l( x ''')  2  

ThePoissonbracketoftwoclassicalfields isequaltothesymplectic metric.

Ontheotherhand,thesymplectic metric isequaltothewedgeproductofbasisvectors.

Infact,thebasisvectorsarequantumoperators,and satisfythequantumcanonicalcommutationrelations: 1 [kxkx (), (')]=δ ( xx − ') ˆ 2 φ Π φ()x= kφ (), x or ˆ ˆ ˆ 1 δ [(),φ xΠ (')] x = ixx ( − ') Π()x = iq2 Π () x Discussion: Prospects for quantum gravity

`Matter’configuration

i asystemofpointparticles X M Acompactnotation X foraconfiguration a(system)ofbranes X ξ( ) etc.

Basisvectors hM

Metric hM ·hN =ηMN

InWittbasiswehaveannihilationandcreationoperators: + − hM, h M + | Ψ〉=(wavepacket profile)( ∏ hM ) | 0 〉 M Expectationvalue

〈ΨhM Ψ〉≡〈1 h M 〉 Inducedmetric

〈hM 〉〈· h M 〉= g MN Iexpectthatingeneralwewillobtainaninducedmetric withnonvanishingcurvature.

Sincespacetime isasubspaceofaconfigurationspace, wewillalsoobtainthemetricofspacetime.

Curvedspacetime metricoriginatesfromquantumconfigurations ofmany`particle’systems. Conclusion

Anactionforaphysicalsystemcanbewritteninthephasespaceform, anditcontainseitherthesymplectic ortheorthogonalform(orboth).

Thecorrespondingbasisvectorssatisfyeitherthefermionic anticommutation relationsorthebosonic commutationrelations, andsatisfytheHeisenbergequationsofmotion.

Quantumoperatorsarejustthebasisvectorsofthephasespaceaction.

Thefactthatbasisvectorsontheonehandarequantumoperators, andontheotherhandtheygivemetric,canbeexploitedinthe developmentofquantumgravity.

AccordingtoFeynmanitisnecessarytoknowseveral differentrepresentationsofthesamephysics.

Wehavepointedouthow`quantization’canbeseen fromyetanotherperspective. Theideathatbasisvectorsarequantumoperatorscanbefoundinabook M.Pavšič: TheLandscapeofTheoreticalPhysics:AGlobalview; FromPointParticlestotheBraneWorldandBeyond,inSearchof aUnifyingPrinciple (Kluwer Academic,2001) wheretheorthogonalandsymplectic casesarediscussed. Verypromisingisthedescriptionofgravityintermsofthe Cliffordalgebra equivalent ofthetetradfieldwhichsimplifiescalculationssignificantly.

Someotherrelatedpublications: Class.Quant.Grav.20,26972714(2003);grqc/0111092 KaluzaKleintheorywithoutextradimensions:CurvedCliffordspace, Phys.Lett.B614,8595(2005);hepth/0412255 SpingaugetheoryofgravityinCliffordspace:ARealizationof KaluzaKleintheoryin 4 dimensionalspacetime,Int.J.Mod.Phys.A21,59055956(2006);grqc/0507053 Beyondtherelativisticpointparticle:Areciprocallyinvariant system, Phys.Lett.B680,526532(2009) Ontherelativityinconfigurationsspace:Arenewedphysicsinsight, 0912.3669[grqc] Spaceinversionofspinors revisited:Apossibleexplanationof chiral behaviorinweakinteractions,Phys.Lett.B692,212217(2010)