Chapter 4: Christoffel Symbols, Geodesic Equations and Killing Vectors Susan Larsen 29 October 2018

Similar documents
Radial geodesics in Schwarzschild spacetime

( ) R kj. = y k y j. y A ( ) z A. y a. z a. Derivatives of the second order electrostatic tensor with respect to the translation of ( ) δ yβ.

Friedmannien equations

Demonstration of the Coupled Evolution Rules 163 APPENDIX F: DEMONSTRATION OF THE COUPLED EVOLUTION RULES

This immediately suggests an inverse-square law for a "piece" of current along the line.

Geometry of the homogeneous and isotropic spaces

General Physics II. number of field lines/area. for whole surface: for continuous surface is a whole surface

EJL R Sβ. sum. General objective: Reduce the complexity of the analysis by exploiting symmetry. Garth J. Simpson

Algebra Based Physics. Gravitational Force. PSI Honors universal gravitation presentation Update Fall 2016.notebookNovember 10, 2016

Electric Potential. and Equipotentials

Physics 505 Fall 2005 Midterm Solutions. This midterm is a two hour open book, open notes exam. Do all three problems.

Electric Field F E. q Q R Q. ˆ 4 r r - - Electric field intensity depends on the medium! origin

U>, and is negative. Electric Potential Energy

EECE 260 Electrical Circuits Prof. Mark Fowler

Collection of Formulas

Partial Derivatives. Limits. For a single variable function f (x), the limit lim

FI 2201 Electromagnetism

set is not closed under matrix [ multiplication, ] and does not form a group.

Two dimensional polar coordinate system in airy stress functions

Section 17.2 Line Integrals

On the Eötvös effect

Space Curves. Recall the parametric equations of a curve in xy-plane and compare them with parametric equations of a curve in space.

Given P(1,-4,-3), convert to cylindrical and spherical values;

Lecture 11: Potential Gradient and Capacitor Review:

Topics for Review for Final Exam in Calculus 16A

13.5. Torsion of a curve Tangential and Normal Components of Acceleration

u(r, θ) = 1 + 3a r n=1

Class Summary. be functions and f( D) , we define the composition of f with g, denoted g f by

The Formulas of Vector Calculus John Cullinan

A New Approach to General Relativity

Math 209 Assignment 9 Solutions

dx was area under f ( x ) if ( ) 0

arxiv: v1 [hep-th] 6 Jul 2016

Homework # 3 Solution Key

1 Using Integration to Find Arc Lengths and Surface Areas

Lots of Calculations in General Relativity Susan Larsen Tuesday, February 03, Introduction Special relativity... 7

Optimization. x = 22 corresponds to local maximum by second derivative test

School of Electrical and Computer Engineering, Cornell University. ECE 303: Electromagnetic Fields and Waves. Fall 2007

MATHEMATICS IV 2 MARKS. 5 2 = e 3, 4

The Schwarzschild Solution

10 m, so the distance from the Sun to the Moon during a solar eclipse is. The mass of the Sun, Earth, and Moon are = =

Now we just need to shuffle indices around a bit. The second term is already of the form

PHZ 3113 Fall 2017 Homework #5, Due Friday, October 13

Homework 3 MAE 118C Problems 2, 5, 7, 10, 14, 15, 18, 23, 30, 31 from Chapter 5, Lamarsh & Baratta. The flux for a point source is:

Solutions to Midterm Physics 201

π,π is the angle FROM a! TO b

d 2 x 0a d d =0. Relative to an arbitrary (accelerating frame) specified by x a = x a (x 0b ), the latter becomes: d 2 x a d 2 + a dx b dx c

Physics 11b Lecture #11

School of Electrical and Computer Engineering, Cornell University. ECE 303: Electromagnetic Fields and Waves. Fall 2007

(6.5) Length and area in polar coordinates

Physics 604 Problem Set 1 Due Sept 16, 2010

The Precession of Mercury s Perihelion

Improper Integrals, and Differential Equations

Week 8. Topic 2 Properties of Logarithms

B.A. (PROGRAMME) 1 YEAR MATHEMATICS

GR Calculations in Specific Bases Using Mathematica

Anonymous Math 361: Homework 5. x i = 1 (1 u i )

10 Statistical Distributions Solutions

Electricity & Magnetism Lecture 6: Electric Potential

Physics 161 Fall 2011 Extra Credit 2 Investigating Black Holes - Solutions The Following is Worth 50 Points!!!

Math 124B February 02, 2012

Summer 2017 MATH Solution to Exercise 5

Stress, Cauchy s equation and the Navier-Stokes equations

Previously. Extensions to backstepping controller designs. Tracking using backstepping Suppose we consider the general system

Causal relation between regions I and IV of the Kruskal extension

Chapter 28 Sources of Magnetic Field

SPA7010U/SPA7010P: THE GALAXY. Solutions for Coursework 1. Questions distributed on: 25 January 2018.

University of. d Class. 3 st Lecture. 2 nd

Math 5440 Problem Set 3 Solutions

Exam 2, Mathematics 4701, Section ETY6 6:05 pm 7:40 pm, March 31, 2016, IH-1105 Instructor: Attila Máté 1

PROPER CURVATURE COLLINEATIONS IN SPECIAL NON STATIC AXIALLY SYMMETRIC SPACE-TIMES

Final Exam Solutions, MAC 3474 Calculus 3 Honors, Fall 2018

Math 5440 Problem Set 3 Solutions

HOMEWORK SOLUTIONS MATH 1910 Sections 7.9, 8.1 Fall 2016

The Concept of the Effective Mass Tensor in GR. Clocks and Rods

1 1D heat and wave equations on a finite interval

Vector d is a linear vector function of vector d when the following relationships hold:

2x (x 2 + y 2 + 1) 2 2y. (x 2 + y 2 + 1) 4. 4xy. (1, 1)(x 1) + (1, 1)(y + 1) (1, 1)(x 1)(y + 1) 81 x y y + 7.

Chapter 7. Kleene s Theorem. 7.1 Kleene s Theorem. The following theorem is the most important and fundamental result in the theory of FA s:

The Dirac distribution

1. The sphere P travels in a straight line with speed

Summary: Method of Separation of Variables

Uniformity of the Universe

Properties of Integrals, Indefinite Integrals. Goals: Definition of the Definite Integral Integral Calculations using Antiderivatives

Chapter 4 Contravariance, Covariance, and Spacetime Diagrams

( dg. ) 2 dt. + dt. dt j + dh. + dt. r(t) dt. Comparing this equation with the one listed above for the length of see that

STD: XI MATHEMATICS Total Marks: 90. I Choose the correct answer: ( 20 x 1 = 20 ) a) x = 1 b) x =2 c) x = 3 d) x = 0

Differential Equations 2 Homework 5 Solutions to the Assigned Exercises

Homework: Study 6.2 #1, 3, 5, 7, 11, 15, 55, 57

Fourier-Bessel Expansions with Arbitrary Radial Boundaries

ELECTRO - MAGNETIC INDUCTION

AQA Further Pure 2. Hyperbolic Functions. Section 2: The inverse hyperbolic functions

Kinematic Waves. These are waves which result from the conservation equation. t + I = 0. (2)

8 Separation of Variables in Other Coordinate Systems

International Journal of Scientific & Engineering Research, Volume 4, Issue 10, October ISSN

Answers to test yourself questions

A DARK GREY P O N T, with a Switch Tail, and a small Star on the Forehead. Any

Physics 3323, Fall 2016 Problem Set 7 due Oct 14, 2016

Higher Checklist (Unit 3) Higher Checklist (Unit 3) Vectors

440-2 Geometry/Topology: Differentiable Manifolds Northwestern University Solutions of Practice Problems for Final Exam

Transcription:

Content 4 Chistoffel Symbols, Geodesic Equtions nd illing Vectos... 4. Chistoffel symbols.... 4.. Definitions... 4.. Popeties... 4..3 The Chistoffel Symbols of digonl metic in Thee Dimensions... 4. Cylindicl coodintes.... 3 4.. The non-zeo Chistoffel symbols... 4 4.. The geodesic eqution fo cylindicl coodintes... 4 4.3 The plne in Ctesin coodintes... 5 4.3. Solve the geodesics equtions of the plne in Ctesin coodintes.... 5 4.4 The Hypebolic Plne... 6 4.4. Geodesics in the Hypebolic Plne... 6 4.5 The Flt Spce-time in two dimension... 8 4.5. The time-like geodesic X(T of the Flt Spce-time metic in two dimensions... 8 4.5. Ae these geodesics spce-like o time-like... 9 4.5.3 Is the wold-line XT Acosh(T time-like o spce-like:... 9 4.6 Thee-dimensionl flt spce-time.... 0 4.6. Null geodesics in thee-dimensionl flt spce-time.... 0 4.7 The wom-hole geomety... 4.7. Volume in the Womhole geomety... 4.7. Equtions fo geodesics in Womhole Geomety... 4.7.3 The tvel time though womhole... 3 4.8 Wp spce-time symmety:... 4 4.8. How much ship time, Δτ, elpses on tip between sttions tht tkes coodinte time t ΔT? 5 4.9 Clssiclly Anti-de Sitte Spcetime... 5 4.9. Clssiclly Anti-de Sitte Spce-time is confomlly elted to the Einstein cylinde... 5 4.9. The Pth of light y the null geodesics in the Clssic Anti de Sitte spce-time... 6 Refeence... 8

4 Chistoffel Symbols, Geodesic Equtions nd illing Vectos 4. Chistoffel symbols. 4.. Definitions The Chistoffel symbols of fist kind Γ bc ( g bc + b g c c g b The Chistoffel symbols of second kind Γ bc gd ( c g db + b g dc d g bc The connection between the Chistoffel symbols of the fist nd the second kind Γ bc g d Γ bcd Notice: The thid subscipt is ised 4.. b Popeties Γ bc ( g bc + b g c c g b ( bg c + g cb c g b Γ bc Γ ( g + g g b ( g Γ b ( g b + g b b g ( g b b g Γ bb Γ bb ( g bb + b g b b g b ( g bb Γ bc + Γ cb ( g bc + b g c c g b + ( g bc + c g b b g c g bc Γ bc gd ( c g db + b g dc d g bc gd ( b g dc + c g db d g cb Γ cb Γ 3 g d Γ d Γ bb g d Γ bbd Γ b Γ b 4 g d Γ bd 4..3 The Chistoffel Symbols of digonl metic in Thee Dimensions The line element ds g xx dx + g yy dy + g zz dz The metic tenso nd its invese g b {g xx g yy g zz } Symmetic in the fist two indices: Γ bc Γ bc Symmetic in the lst two indices: Γ bc Γ cb 3 Only sum ove d 4 Only sum ove d

g b g xx g yy { g zz } The Chistoffel symbols of fist kind Chistoffel symbols of the second kind Γ bc ( g bc + b g c c g b Γ bc g d Γ bcd z y Γ xyz Γ xzy Γ yzx 0 Γ x xy Γ xz Γ yz 0 Γ g Γ 5 g d Γ d Γ xxx x xg xx Γ xx g xx Γ xxx Γ yyy y yg yy Γ yy g yy Γ yyy Γ zzz z zg zz Γ zz g zz Γ zzz Γ b ( g b b g b bg Γ g bd Γ d Γ xxy y yg xx Γ xx g yy Γ xxy Γ xxz z zg xx Γ xx g zz Γ xxz Γ yyx x xg yy Γ yy g xx Γ yyx Γ yyz z zg yy Γ yy g zz Γ yyz Γ zzx x xg zz Γ zz g xx Γ zzx Γ zzy y yg zz Γ zz g yy Γ zzy Γ bb Γ bb b g bb Γ b b Γ b 6 g bd Γ bd Γ xyy Γ yxy y xg yy Γ xy y Γ yx g yy Γ xyy Γ xzz Γ zxz z z xg zz Γ xz Γ zx g zz Γ xzz Γ yxx Γ xyx x x yg xx Γ yx Γ xy g xx Γ yxx Γ yzz Γ zyz z z yg zz Γ yz Γ zy g zz Γ yzz Γ zxx Γ xzx x x zg xx Γ zx Γ xz g xx Γ zxx Γ zyy Γ yzy y zg yy Γ zy y Γ yz g yy Γ zyy 4. c Cylindicl coodintes. The line element: 5 Only sum ove d 6 Only sum ove d 3

ds d + dφ + dz The metic tenso nd its invese: g b { } g b { } 4.. The non-zeo Chistoffel symbols The Chistoffel symbols of fist kind Chistoffel symbols of the second kind Γ bc ( g bc + b g c c g b Γ bc g d Γ bcd Γ φφ g φφ ( Γ φφ Γ φφ Γ φφ g φφ ( φ Γ φ g Γ φφ Γ φ φ g φφ Γ φφ 4.. The geodesic eqution fo cylindicl coodintes 7 The geodesics eqution: d x ds + Γ dx b dx c bc ds ds 0 x : d ds + Γ dx b dx c bc ds ds 0 d (dφ ds ds 0 x d φ: φ ds + Γ φ dx b dx c 0 bc ds ds d φ ds + Γ φ d dφ φ ds ds + Γ φ dφ d 0 φ ds ds d φ ds + d dφ 0 ds ds x z: z bc d z ds + Γ dx ds dx ds 0 d z ds 0 8 The Chistoffel symbols fom the geodesic equtions We hve Now we need x x : g bx x b ( + (φ + (z d ds ( x d ds ( φ d ( ds 7 In this cse we know the Chistoffel symbols nd wnt to find the geodesic equtions 8 In this cse we know the geodesic equtions nd wnt to find the Chistoffel symbols 4

0 φ x φ: φ d ds ( φ 0 d ds ( φ φ + φ 0 φ + φ + φ x z: z d ds ( z 0 d (z z ds Collecting the esults 0 φ 0 φ + φ + φ 0 z We cn now find the Chistoffel symbols fom the geodesic eqution: Γ φφ φ Γ φ Γ φ φ 4.3 The plne in Ctesin coodintes 4.3. d Solve the geodesics equtions of the plne in Ctesin coodintes. We use the Eule-Lgnge method. 0 d ds ( x x F g bx x b The line element ds dx + dy F x + y x x: x 0 x x x 0 x y: 0 y y y y 0 Collecting the esults x 0 y 0 The solution is obviously stight lines: x d x ds 0 5

x dx ds k 0 x k 0 S + k y d y ds 0 y dy ds c 0 y c 0 S + c y 0 x + 4.4 The Hypebolic Plne 4.4. e Geodesics in the Hypebolic Plne The line element: ds y (dx + dy y 0 To find the geodesics we need few integls which we cn solve:. illing vecto: Becuse the metic is independent of x illing vecto is ξ (ξ x, ξ y (,0 Accoding to (8.3 ξ u is conseved quntity long geodesic, whee u (u x, u y ( dx ds, dy ds ξ u ξ u g b ξ b u g x ξ x u g xx ξ x u x y u x dx ds y (I b. The line-element ds y (dx + dy y (( dx ds Substituting (I into (II y ((y + ( dy ds ( dy ds Combining (I nd (III y ( y + ( dy ds (II dy ds ±y y (III dx dy ± y y dx ± ydy y 6

x x 0 ± ydy 9 ± y y (x x 0 + y y 0 If y 0 the geodesics e the veticl lines x x 0 ±. If y > 0 the geodesics e semicicles centeed on the x-xis in (x 0, 0 with dius. x nd y s function of S: dy ds ds ±y y ± dy y y S S 0 ± exp(±(s S 0 dy y y 0 ± ln + y 0 (y exp(±(s S 0 y ( + y y + y y exp(±(s S 0 y exp(±(s S 0 + y y (y( + exp(±(s S 0 exp(±(s S 0 y 0 y exp(s S 0 ( + exp((s S 0 cosh(s S 0 y 3 exp( (S S 0 ( + exp( (S S 0 cosh(s S 0 y dx ds y ( cosh(s S 0 cosh (S S 0 9 (Spiegel, 990 (4.38 d 0 dy (Spiegel, 990 (4.4 ln y y y (+ y ex e x +e x e x (e x +e x e x +e x cosh x e x +e x e x e x (e x +e x e x +e x cosh x 7

x x 0 cosh (S S 0 ds 3 tnh(s S 0 tnh(s S 0 Rescling nd collecting the esults 4 y cosh(s x tnh(s y sinh(s 4.5 The Flt Spce-time in two dimension 4.5. f The time-like geodesic X(T of the Flt Spce-time metic in two dimensions To find X(T we need few integls which we cn solve:.the line element: ds X dt + dx dτ ds X dt dx X ( dt dτ ( dx dτ (I b. illing vectos: Becuse the metic is independent of T illing vecto is ξ (ξ T, ξ X (,0 ξ u is conseved quntity long geodesic, whee u (u T, u X ( dt ξ u dτ dτ ξ u g b ξ b u g TT ξ T u T + g XX ξ X u X X dτ + 0 dτ dt X dt dτ X dt dτ constnt (II Substituting (II into (I dx dτ If dx > 0: dτ Dividing (III by (II dx dτ X dt dτ X ( X 5 ± X X ( dx dτ X (dx dτ (III 3 (Spiegel, 990 (4.57 dx tnh x cosh (x 4 Checking: y ((dx ds + ( dy ds cosh (S (( d( ( cosh(s tnh(s + cosh (S tnh (S 5 > X tnh(s ds + ( d( cosh(s ds cosh S (( cosh (S + 8

dx dt X X X X dt X X dx T T dx X X 6 7 ln ( + X X Isolting X ( + X X exp( (T T ( X exp( (T T X ( X (exp( (T T X X And we find the geodesics exp( (T T + ( X X exp( (T T exp( (T T + exp( (T T exp( (T T + exp(t T cosh(t T X(T 8 cosh(t T 4.5. Ae these geodesics spce-like o time-like ds X dt + dx ( X + ( dx dt dt ( X + ( X X X4 dt cosh 4 (T T dt < 0 So these geodesics e time-like dt 4.5.3 g Is the wold-line X(T A cosh(t time-like o spce-like: ds X dt + dx ( X + ( dx dt dt 6 dx x x 7 ( + X X x ln(+ (Spiegel, 990 (4.4 x > 0 if > X 8 Notice: If dx < 0: X(T dτ cosh(t T cosh(t T 9

( X d(a cosh T + ( dt dt A ( cosh T + sinh TdT A dt < 0 i.e. the wold-line is time-like. 4.6 Thee-dimensionl flt spce-time. 4.6. h Null geodesics in thee-dimensionl flt spce-time. The line element: ds dt + d + dφ To find the null-geodesics we need few integls which we cn solve:. illing vectos: Becuse the metic is independent of t illing vecto is ξ (ξ t, ξ, ξ φ (,0,0 Accoding to (8.3 ξ u is conseved quntity long geodesic, whee u (u t, u, u φ ( dt ds, d ds, dφ ds ξ u ξ u g b ξ b u g t ξ t u g tt ξ t u t + g t ξ t u + g φt ξ t u φ u t dt (I ds Becuse the metic is independent of φ illing vecto is ζ (ζ t, ζ, ζ φ (0,0, ζ u ζ u g b ζ b u g φ ζ φ u g tφ ζ φ u t + g φ ζ φ u + g φφ ζ φ u φ u φ dφ (II ds b. Consevtion of the fou-velocity fo light y u u 0 u u g b u b u g tt u t u t + g u u + g φφ u φ u φ ( dt ds + ( d ds + ( dφ ds 0 ( dt ds + ( d ds + ( dφ ds Inseting (I nd (II into (III 0 ( + ( d ds + ( ( d ds Combining (I nd (IV d ds d dt ( ( ( ( (IV ( ( ( (III 0

dt d ( d ( t t 0 d ( Notice we cn ewite this into hypeboloid. 9 ( ( (t t 0 (V Combining (I, (II nd (V dφ dt dφ dt φ φ 0 (t t 0 + ( t t 0 tn(φ φ 0 Combining (V nd (VI ( dt (t t 0 + ( 0 tn [ (t t 0 ] tn(φ φ 0 ± tn (φ φ 0 + Collecting the esults we find the null-geodesics: ( (V (VI (VII (t t 0 (V t t 0 tn(φ φ 0 ± tn (φ φ 0 + (VII Light ys moves on stight lines in cuved spce. Fom ou point of view the tip of the light cone (t, moves long hypebolic pth eq. (V. 4.7 The wom-hole geomety 4.7. i Volume in the Womhole geomety The thee-dimensionl volume on t constnt slice of the womhole geomety bounded by two sphees of coodinte dius R on ech side of the thot. The line-element ds dt + d + (b + (dθ + sin θ dφ (VI 9 (Spiegel, 990 (4.0 d 0 (Spiegel, 990 (4.5 dt t + tn t

The volume V dl dl dl 3 R (b + d R R 4π (b + d R 4π [b + 3 3 ] R π sin θ dθ 0 R π dφ 0 4π ((Rb + 3 R3 (( Rb + 3 ( R3 4π 3 R (3b + R 4.7. j Equtions fo geodesics in Womhole Geomety We use the Eule-Lgnge method. 0 d ds ( x x F g bx x b The line element ds dt + d + (b + (dθ + sin θ dφ F t + + (b + θ + (b + sin θ φ x t: 0 t t t t 0 x : (θ + sin θ φ θ + sin θ φ x θ: θ (b + sin θ cos θ φ (b θ + θ d ds ( θ + (b θ + θ θ sin θ cos θ φ x φ: φ 0 φ (b + sin θ φ (b + θ 0 d ds ((b + sin θ φ sin θ φ + (b + sin θ cos θ θ φ + (b + sin θ φ

φ (b + φ cot θ θ φ Collecting the esults t 0 θ + sin θ φ θ sin θ cos θ φ (b + θ φ (b + φ cot θ θ φ k The non-zeo Chistoffel symbols e Γ θθ Γ φφ sin θ θ Γ φφ φ Γ φ θ sin θ cos θ Γ θ Γ φ φ (b + φ Γ θφ θ Γ θ φ Γ φθ (b + cot θ 4.7.3 l The tvel time though womhole Use the geodesic equtions to clculte the pope tvel time of n stonut tvelling though womhole thot long the coodinte dius fom R to R. The initil dil fou-velocity is u U, nd becuse of spheiclly symmety u θ u φ 0 The fou-velocity is u (u t, u, u θ, u φ ( dt dτ, d dτ, dθ dτ, dφ dτ ( + U, U, 0, 0 we will only look t u. We use the geodesic eqution θ + sin θ φ which we cn ewite d θ + sin θ φ 0 dτ d d dτ dτ (d dτ du dτ 0 which implies tht u U is constnt long the stonuts wold-line. So we cn solve u d dτ U dτ U d R Δτ U d R U [] R R U (R ( R R U So the tvel time though the womhole Δτ R is vey much like the usul time/speed clcultion: U distncetime*velocity except with the velocity eplced by the fou velocity. 4.7.3. Is the tjectoy time-like o spce-like? The line-element dτ dt d (b + (dθ + sin θ dφ u t is found fom the fct tht the u u is conseved quntity: u u u η ij u (u t + (u + (u θ + (u φ (u t + U u t + U, whee + U > 0 If we insted used the line-element dτ dt + d + (b + (dθ + sin θ dφ we would find dt ( +U < 0, which in this cse lso is time-like. You lwys hve to ceful whethe you choose positive o negtive signtue. 3

dt ( ( d dt (b + (( dθ dt + sin θ ( dφ dt 3 dt ( ( d dτ dτ dt (b + ((0 + sin θ (0 dt ( (U + U dt ( + U U + U dt ( + U > 0 i.e. the tjectoy is time-like. 4.8 m Wp spce-time symmety: The line-element ds dt + [dx V s (tf( s dt] + dy + dz dτ ds dt [dx V s (tf( s dt] dy dz ( V s (t f( s dt + V s (tf( s dxdt dx dy dz Notice: The line-element is dependent on the velocity of the spceship V s (t. If the velocity is zeo the line-element educes to flt Minkowsky spce-time. The metic + V s (t f( s V s (tf( s 0 0 g b { V s (tf( s 0 0 } 0 0 0 0 0 0 nd f( s is ny smooth positive function tht stisfies f(0 nd deceses wy Whee V s (t dx s (t dt fom the oigin to vnish fo s > R fo some R, s [(x x s (t + y + z ] A spceship tvels long cuve (t, x, y, z (t, x s (t, 0,0 With the fou-velocity u (u t, u x, u y, u z ( dt dτ, dx s(t, 0,0 dτ Mnipulting the metic we get dτ dt [dx V s (tf( s dt] dy dz ( [ dx dt V s(tf( s ] ( [ dx s(t V dt s (tf( s ] ( dy dt ( dz dt dt dt ( [ f( s ] V s (t dt > 0 Which mens the tjectoy is time-like nd t evey point long the cuve (t, x, y, z (t, x s (t, 0,0 the fou-velocity of the spceship lies inside the light cone if V s (t <, i.e. smlle thn the velocity of light. 3 Becuse ll the diffeentils with espect to θ nd φ e zeo, we cn use the chin ule in this simple mnne. 4

4.8. How much ship time, Δτ, elpses on tip between sttions tht tkes coodinte time t ΔT? The metic dτ dt [dx V s (tf( s dt] dy dz ( dτ dt [ dx dt V s(tf( s ] ( dy dt ( dz dt The ship moves on cuve in the (x, y-plne with the coodintes (t, x s (t, 0,0 ( dτ dt [ dx s(t V dt s (tf( s ] [V s (t V s (tf( s ] V s (t [ f( s ] dτ V s (t [ f( s ] dt If we ssume the spceship hs constnt velocity V s (t V s (0 Δτ V s (0 [ f( s ] ΔT In detil Δτ fo s 0 ΔT { Δτ V s (0 > Δτ fo s > R The light cone: The line-element is depending on the velocity of light. This hs the peculi effect. 0 dt + [dx V s (tf( s dt] ( + [ dx dt V s(tf( s ] dt dx dt ± + V s (tf( s Now, s you cn see thee e es whee dx is lge the thn one. This mens tht fom ou point of dt view, thee e es whee the spceship seems to move with velocity lge thn the speed of light. Thee is no contdiction hee though, becuse loclly the velocity of the spceship V s (t is smlle thn the speed of light. 4.9 n Clssiclly Anti-de Sitte Spcetime 4.9. Clssiclly Anti-de Sitte Spce-time is confomlly elted to the Einstein cylinde The line element ds cosh ( dt + d + sinh ( dθ + sinh ( sin θ dφ We use the tnsfomtion cosh( cos ψ sinh ( cos ψ tn ψ d(cosh( d ( cos ψ sinh( d sin ψ cos ψ dψ d sin ψ sinh ( cos 4 ψ dψ cos ψ dψ ds cos ψ dt + cos ψ dψ + tn ψ dθ + tn ψ sin θ dφ cos ψ ( dt + dψ + sin ψ dθ + sin ψ sin θ dφ Which is confomlly elted to the Einstein cylinde ds dt + ( 0 (dθ + sin θ (dφ + sin φ dψ 5

4.9. The Pth of light y the null geodesics in the Clssic Anti de Sitte spce-time To find the null-geodesics we need some integls which we cn solve:. illing vectos: Becuse the metic is independent of t illing vecto is ξ (ξ t, ξ, ξ θ, ξ φ (,0,0,0 ξ u is conseved quntity long geodesic, whee u (u t, u, u θ, u φ ( dt ds, d ds, dθ ds, dφ ds ξ u ξ u g b ξ b u g t ξ t u g tt ξ t u t + g t ξ t u + g θt ξ t u θ + g φt ξ t u φ cosh ( t t cosh ( Becuse the metic is independent of φ illing vecto is ζ (ζ t, ζ, ζ θ, ζ φ (0,0,0, ζ u ζ u g b ζ b u g φ ζ φ u g tφ ζ φ u t + g φ ζ φ u + +g θφ ζ φ u θ + g φφ ζ φ u φ sinh ( sin θ u φ φ sinh ( sin θ (II b. Consevtion of the fou-velocity fo light y u u 0 u u g b u b u g tt u t u t + g u u + g θθ u θ u θ + g φφ u φ u φ cosh ( t + + sinh ( θ + sinh ( sin θ φ 0 cosh ( t + + sinh ( θ + sinh ( sin θ φ (III c. The geodesic equtions. We use the Eule-Lgnge method. 0 d ds ( x x F g bx x b cosh ( t + + sinh ( θ + sinh ( sin θ φ x t: 0 t cosh ( t t d ds ( cosh ( t sinh( t t 0 cosh ( t + sinh( t (IV x : sinh( t + cosh( θ + cosh( sin θ φ (I 6

d ds ( 0 + sinh( t cosh( θ cosh( sin θ φ (V x θ: θ sinh ( cos θ φ θ sinh ( θ d ds ( cosh( θ + sinh θ ( θ 0 cosh( θ + sinh ( θ sinh ( cos θ φ (VI x φ: φ 0 φ sinh ( sin θ φ d ds ( φ cosh( sin θ φ + sinh ( cos θ φ + sinh ( sin θ φ 0 cosh( sin θ φ + sinh ( cos θ φ + sinh ( sin θ φ (VII Collecting the esults t cosh ( φ sinh ( sin θ (II 0 cosh ( t + + sinh ( θ + sinh ( sin θ φ (III 0 cosh ( t + sinh( t (IV 0 + sinh( t cosh( θ cosh( sin θ φ (V 0 cosh( θ + sinh ( θ sinh ( cos θ φ (VI 0 cosh( sin θ φ + sinh ( cos θ φ + sinh ( sin θ φ (VII The coodintes t nd : We need t sinh( cosh( cosh 4 ( (I Substituting (I nd (I into (IV 0 cosh sinh( cosh( ( ( cosh 4 ( + sinh( ( cosh ( 0 cosh( + cosh( (VIII Dividing (I with (VIII dt t t dt t 0 d cosh 3 ( cosh 3 ( d 0 (I 7

t t 0 4 [ sinh( cosh ( ] 0 + d cosh( 0 5 [ sinh( cosh ( + tn (e ] 0 sinh( cosh ( + tn (e ( sinh( 0 cosh ( 0 + tn (e 0 sinh( cosh ( + tn (e 3 0 0 4 Intepeting this mens, tht no mtte how f the light tvels in this spcetime fom 0 to this hppens within limited time 6. As n execise we will look t the othe coodintes s well. The coodintes nd θ : We need cosh( sinh( cos θ sin θ φ ( sinh 4 ( sin + θ sinh ( sin 4 θ θ cosh( sinh( cos θ sin θ ( sinh 4 ( sin cosh( + θ sinh ( sin 4 θ θ (II Mnipulte eq. (VII nd substitute (II nd (II 0 cosh( sin θ φ + sinh ( cos θ φ + sinh ( sin θ φ θ 7 [ cosh( cos θ sinh + ( sin θ cosh ( sinh( cosh( tn θ sinh ( + sin θ cosh ( tn θ sinh( cos θ sin θ θ ] Dividing (IX with (VIII: θ dθ d tn θ sinh ( + cosh( sin θ tn θ tnh( This illusttes how difficult it is to solve the geodesic equtions in GR. (IX Refeence Choquet-Buht, Y. (05. Intoduction to Genel Reltivity, Blck Holes nd Cosmology. Oxfod: Oxfod Univesity Pess. Htle, J. B. (003. An Intoduction to Einstein's Genel Reltivity. Sn Fncisco: Peson Eduction. Htle, J. B. (003. Gvity - An intoduction to Einstein's Genel Reltivity. Addison Wesley. y, D. C. (988. Tenso Clculus. McGw-Hill. McMhon, D. (006. Reltivity Demystified. McGw-Hill. 4 d sinh( + (n cosh n ( (n cosh n ( (n d cosh n ( (4.588 (Spiegel, 990 5 d cosh( tn (e (4.567 (Spiegel, 990 6 Notice: We hven t used eq. (III so this esult lso vlid fo n object with mss. cosh( sinh( 7 cosh( sin θ + sinh ( sin θ sinh ( cos θ + sinh ( sin θ sinh ( sin θ [ ( cosh( + sinh 4 ( sin θ cos θ sin θ θ ] sinh ( sin 4 θ 8

Spiegel, M. R. (990. SCHAUM'S OUTLINE SERIES: Mthemticl Hndbook of FORMULAS nd TABLES. McGw-Hill Publishing Compny. (McMhon, 006, s. 7-73, (d'inveno, 99, p. 83, (y, 988, s. 68-70, 74-75 b (McMhon, 006, s. 34, (y, 988, s. 68-70, 74-75 c (McMhon, 006, s. 83 d (Htle, Gvity - An intoduction to Einstein's Genel Reltivity, 003, p. 83 e (Htle, An Intoduction to Einstein's Genel Reltivity, 003, s. 84 f (Htle, Gvity - An intoduction to Einstein's Genel Reltivity, 003, p. 84 g (Htle, Gvity - An intoduction to Einstein's Genel Reltivity, 003, p. 43 h (Htle, Gvity - An intoduction to Einstein's Genel Reltivity, 003, p. 84 i (Htle, Gvity - An intoduction to Einstein's Genel Reltivity, 003, p. 66 j (Htle, Gvity - An intoduction to Einstein's Genel Reltivity, 003, p. 7 k (Htle, Gvity - An intoduction to Einstein's Genel Reltivity, 003, p. 74 l (Htle, Gvity - An intoduction to Einstein's Genel Reltivity, 003, p. 75 m (Htle, Gvity - An intoduction to Einstein's Genel Reltivity, 003, pp. 44, 66 n (Choquet-Buht, 05, s. 97 9