script, 1.1, 1.2

Question 1

cosmo assumptins?

Answer 1

1. isotropy (dir Independent,)
2. cosmo prnciple: our not preferred position

homogenous n isotropic universe

Question 2

fundamental assumptions?

Answer 2

observable properties are isotropic wrt mean motion of matter n energy

fundamental obs experience same universe,

Question 3

comoving cord?

Answer 3

spatial coordinates of fundamental observers

funda obs: stationary wrt to cosmic fluid (mean matter n energy)

Comoving distance factors out the expansion of the universe

dxi = 0

Question 4

ds and g00 for coming cord?

Answer 4

dxi = 0

ds2 = g00 cdt2 = -c2 dt2

g00 = -c^2

Question 5

scaling function a (t)?

Answer 5

scales spatial hyper surface by: gij dxi dxj = a(t)^2 dl^2

Question 6

cosmo redshift,

dt0 / dte = a0 / ae

shows?

Answer 6

dt0 time at obs
die t at emission

a0, ae scaling fun at abs and emission

eq: time intervals change wrt abs = change in scale of uni btw emission n obs

Question 7

eq of redshift?

explain?

Answer 7

1 + z = a0/ae

redshift of light promotional to change of scale of uni

Question 8

how do each parameter (radiation, density, cosmo cont, curvature) scale?
what do each parameter mean?

Answer 8

a

Question 9

what a_eq?

Answer 9

a

Question 10

find time of a_eq

Answer 10

a_eq= omega_ro / omega_po

a = ( )^ 1/2.. eq1.52 from Hubble eq

Question 11

how a scales with t in early rad dominated uni?

Answer 11

a ~ t^1/2

Question 12

how a scales with t in matter dominated uni?

Answer 12

a ~ t^2/3

Question 13

what’s Einstein de sitters limit

Answer 13

a ~ t^2/3

a scale with t in matter domination era

Question 14

de sitters limit?

Answer 14

a = exp (Ho t sqrt(omegą_lamda) )

says that combo cosnt is causing expo expansion