Top Banner
ON HORIZONTAL AND COMPLETE LIFTS FROM A MANIFOLD WITH f λ (7,1)-STRUCTURE TO ITS COTANGENT BUNDLE LOVEJOY S. DAS, RAM NIVAS, AND VIRENDRA NATH PATHAK Received 1 August 2003 The horizontal and complete lifts from a manifold M n to its cotangent bundles T (M n ) were studied by Yano and Ishihara, Yano and Patterson, Nivas and Gupta, Dambrowski, and many others. The purpose of this paper is to use certain methods by which f λ (7, 1)- structure in M n can be extended to T (M n ). In particular, we have studied horizontal and complete lifts of f λ (7,1)-structure from a manifold to its cotangent bundle. 1. Introduction Let M be a dierentiable manifold of class c and of dimension n and let C TM denote the cotangent bundle of M. Then C TM is also a dierentiable manifold of class c and dimension 2n. The following are notations and conventions that will be used in this paper. (1) r s (M) denotes the set of tensor fields of class c and of type (r , s) on M. Similarly, r s (C TM ) denotes the set of such tensor fields in C TM . (2) The map Π is the projection map of C TM onto M. (3) Vector fields in M are denoted by X , Y , Z , ... and Lie dierentiation by L X . The Lie product of vector fields X and Y is denoted by [X , Y ]. (4) Suxes a, b, c, ... ,h, i, j , ... take the values 1 to n and i = i + n. Suxes A, B, C, ... take the values 1 to 2n. If A is a point in M, then Π 1 (A) is fiber over A. Any point p Π 1 (A) is denoted by the ordered pair (A, p A ), where p is 1-form in M and p A is the value of p at A. Let U be a coordinate neighborhood in M such that A U . Then U induces a coordinate neighborhood Π 1 (U ) in C TM and p Π 1 (U ). 2. Complete lift of f λ (7,1)- structure Let f (= 0) be a tensor field of type (1, 1) and class c on M such that f 7 + λ 2 f = 0, (2.1) Copyright © 2005 Hindawi Publishing Corporation International Journal of Mathematics and Mathematical Sciences 2005:8 (2005) 1291–1297 DOI: 10.1155/IJMMS.2005.1291
8

On horizontal and complete lifts from a manifold …downloads.hindawi.com/journals/ijmms/2005/812037.pdf1292 Horizontal and complete lifts of f λ(7,1)-structure where λis any complex

May 31, 2020

Download

Documents

dariahiddleston
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Page 1: On horizontal and complete lifts from a manifold …downloads.hindawi.com/journals/ijmms/2005/812037.pdf1292 Horizontal and complete lifts of f λ(7,1)-structure where λis any complex

ON HORIZONTAL AND COMPLETE LIFTS FROMA MANIFOLD WITH fλ(7,1)-STRUCTURE TO ITSCOTANGENT BUNDLE

LOVEJOY S. DAS, RAM NIVAS, AND VIRENDRA NATH PATHAK

Received 1 August 2003

The horizontal and complete lifts from a manifold Mn to its cotangent bundles∗T(Mn)

were studied by Yano and Ishihara, Yano and Patterson, Nivas and Gupta, Dambrowski,and many others. The purpose of this paper is to use certain methods by which fλ(7,1)-

structure in Mn can be extended to∗T(Mn). In particular, we have studied horizontal and

complete lifts of fλ(7,1)-structure from a manifold to its cotangent bundle.

1. Introduction

Let M be a differentiable manifold of class c∞ and of dimension n and let CTM denotethe cotangent bundle of M. Then CTM is also a differentiable manifold of class c∞ anddimension 2n.

The following are notations and conventions that will be used in this paper.(1) �r

s (M) denotes the set of tensor fields of class c∞ and of type (r,s) on M. Similarly,�rs (CTM) denotes the set of such tensor fields in CTM.

(2) The map Π is the projection map of CTM onto M.(3) Vector fields in M are denoted by X ,Y ,Z, . . . and Lie differentiation by LX . The Lie

product of vector fields X and Y is denoted by [X ,Y].(4) Suffixes a,b,c, . . . ,h, i, j, . . . take the values 1 to n and i = i + n. Suffixes A,B,C, . . .

take the values 1 to 2n.If A is a point in M, then Π−1(A) is fiber over A. Any point p ∈ Π−1(A) is denoted

by the ordered pair (A, pA), where p is 1-form in M and pA is the value of p at A. LetU be a coordinate neighborhood in M such that A ∈ U . Then U induces a coordinateneighborhood Π−1(U) in CTM and p ∈Π−1(U).

2. Complete lift of fλ(7,1)- structure

Let f ( �= 0) be a tensor field of type (1,1) and class c∞ on M such that

f 7 + λ2 f = 0, (2.1)

Copyright © 2005 Hindawi Publishing CorporationInternational Journal of Mathematics and Mathematical Sciences 2005:8 (2005) 1291–1297DOI: 10.1155/IJMMS.2005.1291

Page 2: On horizontal and complete lifts from a manifold …downloads.hindawi.com/journals/ijmms/2005/812037.pdf1292 Horizontal and complete lifts of f λ(7,1)-structure where λis any complex

1292 Horizontal and complete lifts of fλ(7,1)-structure

where λ is any complex number not equal to zero. We call the manifold M satisfying(2.1) as fλ(7,1)-structure manifold. Let f hi be components of f at A in the coordinateneighborhood U of M. Then the complete lift f c of f is also a tensor field of type (1,1)in CTM whose components f̃ AB in Π−1(U) are given by [2]

f̃ hi = f hi ; f hi = 0, (2.2)

f̃ hi = Pa

(∂ f ah∂xi

∂ f ai∂xh

); f̃ hi = f ih , (2.3)

where (x1,x2, . . . ,xn) are coordinates of A relative to U and pA has a component (p1, p2,. . . ,pn).

Thus we can write

f C =(f̃ AB)= f hi 0

pa(∂i f

ah − ∂h f

ai

)f ih

, (2.4)

where ∂i = ∂/∂xi.If we put

∂i fah − ∂h f

ai = 2∂

[i f ah], (2.5)

then we can write (2.4) in the form

f C = ( f AB )= f hi 0

2pa∂[i f ah]

f ih

. (2.6)

Thus we have

(f C)2 =

f hi 0

2pa∂[i f ah]

f ih

f ij 0

2pt∂[j f ti]

fji

, (2.7)

or

(f C)2 =

f hi f ij 0

2pa f lj ∂[i f ah]

+ 2pt f ih∂[j f ti]

fji f ih

. (2.8)

If we put

2pa f lj ∂[i f ah]

+ 2pt f ih∂[j f ti]= Lhj , (2.9)

then (2.8) takes the form

(f C)2 =

(f hi f ij 0

Lhj fji f ih

). (2.10)

Page 3: On horizontal and complete lifts from a manifold …downloads.hindawi.com/journals/ijmms/2005/812037.pdf1292 Horizontal and complete lifts of f λ(7,1)-structure where λis any complex

Lovejoy S. Das et al. 1293

Thus we have

(f C)4 =

f hi f ij 0

Lhj fji f ih

f

jk f kl 0

Ljl f lk fkj

, (2.11)

or

(f C)4 =

f hi f ij f

jk f kl 0

fjk f kl Lh j + f

ji f ihLjl f lk f

kj f

ji f ih

. (2.12)

Putting again

fjk f kl Lh j + f

ji f ihLjl = Phl, (2.13)

then we can put (2.12) in the form

(f C)4 =

f hi f ij f

jk f kl 0

Phl f lk fkj f

ji f ih

. (2.14)

Thus,

(f C)6 =

f hi f ij f

jk f kl 0

Phl f lk fkj f

ji f ih

f lm f mn 0

Lln f nm f ml

, (2.15)

(f C)6 =

f hi f ij f

jk f kl f lm f mn 0

Phl f lm f mn +Lln flk f

kj f

ji f ih f nm f ml f lk f

kj f

ji f ih

. (2.16)

Putting again

Phl flm f mn +Lln f

lk f

kj f

ji f ih =Qhn, (2.17)

then (2.16) takes the form

(f C)6 =

f hi f ij f

jk f kl f lm f mn 0

Qhn f nm f ml f lk fkj f

ji f ih

. (2.18)

Page 4: On horizontal and complete lifts from a manifold …downloads.hindawi.com/journals/ijmms/2005/812037.pdf1292 Horizontal and complete lifts of f λ(7,1)-structure where λis any complex

1294 Horizontal and complete lifts of fλ(7,1)-structure

Thus,

(f C)7 =

f hi f ij f

jk f kl f lm f mn 0

Qhn f nm f ml f lk fkj f

ji f ih

f np 0

2pr∂[p f rn

]fpn

, (2.19)

(f C)7 =

f hi f ij f

jk f kl f lm f mn f np 0

Qhn f np + 2pr∂[p f rn

]f nm f ml f lk f

kj f

ji f ih f

pn f nm f ml f lk f

kj f

ji f ih

. (2.20)

In view of (2.1), we have

f hi f ij fjk f kl f lm f mn f np =−λ2 f hp , (2.21)

and also putting

Qhn fnp + 2pr∂

[p f rn

]f nm f ml f lk f

kj f

ji f ih =−λ2ps∂

[p f sh

], (2.22)

then (2.20) can be given by

(f C)7 =

−λ2 f np 0

−λ2ps∂[p f sh

] −λ2 fph

. (2.23)

In view of (2.6) and (2.23), it follows that

(f C)7

+ λ2( f C)= 0. (2.24)

Hence the complete lift f C of f admits an fλ(7,1)-structure in the cotangent bundleCTM.

Thus we have the following theorem.

Theorem 2.1. In order that the complete lift of f C of a (1,1) tensor field f admittingfλ(7,1)-structure in M may have the similar structure in the cotangent bundle CTM, it isnecessary and sufficient that

Qhn fnp + 2pr∂

[p f rn

]f nm f ml f lk f

kj f

ji f ih =−λ2ps∂

[p f sh

]. (2.25)

3. Horizontal lift of fλ(7,1)-structure

Let f , g be two tensor fields of type (1,1) on the manifold M. If f H denotes the horizontallift of f , we have

f HgH + gH f H = ( f g + g f )H. (3.1)

Taking f and g identical, we get

(f H)2 = ( f 2)H. (3.2)

Page 5: On horizontal and complete lifts from a manifold …downloads.hindawi.com/journals/ijmms/2005/812037.pdf1292 Horizontal and complete lifts of f λ(7,1)-structure where λis any complex

Lovejoy S. Das et al. 1295

Multiplying both sides by f H and making use of the same (3.2), we get

(f H)3 = ( f 3)H (3.3)

and so on. Thus it follows that

(f H)4 = ( f 4)H ,

(f H)5 = ( f 5)H , (3.4)

and so on. Thus,

(f H)7 = ( f 7)H. (3.5)

Since f gives on M the fλ(7,1)-structure, we have

f 7 + λ2 f = 0. (3.6)

Taking horizontal lift, we obtain

(f 7)H + λ2( f H)= 0. (3.7)

In view of (3.5) and (3.7), we can write

(f H)7

+ λ2( f H)= 0. (3.8)

Thus the horizontal lift f H of f also admits a fλ(7,1)-structure. Hence we have thefollowing theorem.

Theorem 3.1. Let f be a tensor field of type (1,1) admitting fλ(7,1)-structure in M. Thenthe horizontal lift f H of f also admits the similar structure in the cotangent bundle CTM.

4. Nijenhuis tensor of complete lift of f 7

The Nijenhuis tensor of a (1,1) tensor field f on M is given by

Nf , f (X ,Y)= [ f X , f Y]− f [ f X ,Y]− f [X , f Y] + f 2[X ,Y]. (4.1)

Also for the complete lift of f 7, we have

N(f 7)C,

(f 7)C(XC,YC

)= [( f 7)CXC,(f 7)CYC

]− ( f 7)C[( f 7)CXC,YC

]− ( f 7)C[XC,

(f 7)CYC

]+(f 7)C( f 7)C[XC,YC

].

(4.2)

In view of (2.1), the above (4.2) takes the form

N(f 7)C,

(f 7)C(XC,YC

)=[(− λ2 f

)CXC,

(− λ2 f)CYC]− (− λ2 f

)C[(− λ2 f)CXC,YC

]− (− λ2 f

)C[XC,

(− λ2 f)CYC]

+(− λ2 f

)C(− λ2 f)C[

XC,YC],

(4.3)

Page 6: On horizontal and complete lifts from a manifold …downloads.hindawi.com/journals/ijmms/2005/812037.pdf1292 Horizontal and complete lifts of f λ(7,1)-structure where λis any complex

1296 Horizontal and complete lifts of fλ(7,1)-structure

or

N(f 7)C,

(f 7)C(XC,YC

)= λ4

{ [( f )CXC, ( f )CYC

]− ( f )C[( f )CXC,YC

]−( f )C

[XC, ( f )CYC

]+ ( f )C( f )C

[XC,YC

]}. (4.4)

We also know that [3]

( f )CXC = ( f X)C + v(�X f

), (4.5)

where v f has components

v f =(Oa

Pa fi

). (4.6)

In view of (4.5), (4.4) takes the form

N(f 7)C,

(f 7)CXC,YC

= λ4

[( f X)C, ( f Y)C

]+[v(�X f

), ( f Y)C

]+[( f X)C,v

(�Y f

)]+[v(�X f

),v(�Y f

)]− ( f )C[( f X)C,YC

]− ( f )C[v(�X f

),YC

]−( f )C

[XC, ( f Y)C

]− ( f )C[XC,v

(�Y f

)C]+ ( f )C( f )C

[XC,YC

] .

(4.7)

We now suppose that

�X f =�Y f = 0. (4.8)

Then from (4.7), we have

N(f 7)C,

(f 7)C(XC,YC

)= λ4

{ [( f X)C, ( f Y)C

]− ( f )C[( f X)C,YC

]−( f )C

[XC, ( f Y)C

]+ ( f )C( f )C

[XC,YC

]}. (4.9)

Further, if f acts as an identity operator on M [2], that is,

f X = X ∀X ∈�10(M), (4.10)

then we have from (4.9)

N(f 7)C,

(f 7)C(XC,YC

)= λ8{[XC,YC]− [XC,YC

]− [XC,YC]

+[XC,YC

]}= 0.(4.11)

Hence we have the following theorem.

Theorem 4.1. The Nijenhuis tensor of the complete lift of f 7 vanishes if the Lie derivativesof the tensor field f with respect to X and Y are both zero and f acts as an identity operatoron M.

Page 7: On horizontal and complete lifts from a manifold …downloads.hindawi.com/journals/ijmms/2005/812037.pdf1292 Horizontal and complete lifts of f λ(7,1)-structure where λis any complex

Lovejoy S. Das et al. 1297

References

[1] R. Dombrowski, On the geometry of the tangent bundle, J. reine angew. Math. 210 (1962), 73–88.

[2] V. C. Gupta and R. Nivas, On problems relating to horizontal and complete lifts of φµ structure,Nepali Math Sciences Reports, Nepal, 1985.

[3] K. Yano and S. Ishihara, Tangent and Cotangent Bundles: Differential Geometry, Marcel Dekker,New York, 1973.

[4] K. Yano and E. M. Patterson, Horizontal lifts from a manifold to its cotangent bundle, J. Math.Soc. Japan 19 (1967), 185–198.

Lovejoy S. Das: Department of Mathematics, Kent State University Tuscarawas, New Philadelphia,OH 44663, USA

E-mail address: [email protected]

Ram Nivas: Lucknow University, Lucknow, UP 226007, IndiaE-mail address: [email protected]

Virendra Nath Pathak: Lucknow University, Lucknow, UP 226007, India

Page 8: On horizontal and complete lifts from a manifold …downloads.hindawi.com/journals/ijmms/2005/812037.pdf1292 Horizontal and complete lifts of f λ(7,1)-structure where λis any complex

Submit your manuscripts athttp://www.hindawi.com

Hindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

MathematicsJournal of

Hindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

Mathematical Problems in Engineering

Hindawi Publishing Corporationhttp://www.hindawi.com

Differential EquationsInternational Journal of

Volume 2014

Applied MathematicsJournal of

Hindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

Probability and StatisticsHindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

Journal of

Hindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

Mathematical PhysicsAdvances in

Complex AnalysisJournal of

Hindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

OptimizationJournal of

Hindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

CombinatoricsHindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

International Journal of

Hindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

Operations ResearchAdvances in

Journal of

Hindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

Function Spaces

Abstract and Applied AnalysisHindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

International Journal of Mathematics and Mathematical Sciences

Hindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

The Scientific World JournalHindawi Publishing Corporation http://www.hindawi.com Volume 2014

Hindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

Algebra

Discrete Dynamics in Nature and Society

Hindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

Hindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

Decision SciencesAdvances in

Discrete MathematicsJournal of

Hindawi Publishing Corporationhttp://www.hindawi.com

Volume 2014 Hindawi Publishing Corporationhttp://www.hindawi.com Volume 2014

Stochastic AnalysisInternational Journal of