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Oct 10, 2011, 9:07:11 AM10/10/11

to

The Friedmann equation is the most important

laws which describes the evolution of the Universe.

In order to understand its behaviour I have written an Excel

program which allows me to study this equation for different

parameters.

The document which describes the results can be found

here:

http://users.telenet.be/nicvroom/friedmann's%20equation.htm

The idea of the document is to calculate the path of a lightray

which starts at the BigBang and which reaches

the observer now using the Friedmann equation as described

in the book "Introducing Einstein's Relativity" by d''Inverno

for three paramaters: C, labda and k.

When you have this path you can also calculate the redshift

(z) which the observer observes depending what the

origin (as a function of distance) is of the light source.

What my results show is that the results are highly non linear

The question than pops up to what extend based on actual

observation you can use z as an indication for distance.

The same problems arise if you calculate H0 which is

measured near the observer.

The question is to what extend can you use the parameter

1/H0 in order to calculate the age of the Universe.

What my results also show that the relation v = z * c

is only true near the observer. For larger distances

this relation is non linear.

Space acceleration (Global and Local) is also discussed.

laws which describes the evolution of the Universe.

In order to understand its behaviour I have written an Excel

program which allows me to study this equation for different

parameters.

The document which describes the results can be found

here:

http://users.telenet.be/nicvroom/friedmann's%20equation.htm

The idea of the document is to calculate the path of a lightray

which starts at the BigBang and which reaches

the observer now using the Friedmann equation as described

in the book "Introducing Einstein's Relativity" by d''Inverno

for three paramaters: C, labda and k.

When you have this path you can also calculate the redshift

(z) which the observer observes depending what the

origin (as a function of distance) is of the light source.

What my results show is that the results are highly non linear

The question than pops up to what extend based on actual

observation you can use z as an indication for distance.

The same problems arise if you calculate H0 which is

measured near the observer.

The question is to what extend can you use the parameter

1/H0 in order to calculate the age of the Universe.

What my results also show that the relation v = z * c

is only true near the observer. For larger distances

this relation is non linear.

Space acceleration (Global and Local) is also discussed.

What the results also show is that the more

parameters are non zero in the Friedmann

equation the more difficult it becomes to calculate

the indivudual parameters.

The source of the program is available on request.

Nicolaas Vroom

http://users.pandora.be/nicvroom/

Oct 10, 2011, 10:26:07 AM10/10/11

to

On Oct 10, 9:07�am, Nicolaas Vroom <nicolaas.vr...@telenet.be> wrote:

> What my results show is that the results are highly non linear

> The question than pops up to what extend based on actual

> observation you can use z as an indication for distance.

> The same problems arise if you calculate H0 which is

> measured near the observer.

> The question is to what extend can you use the parameter

> 1/H0 in order to calculate the age of the Universe.

> What my results also show that the relation v = z * c

> is only true near the observer. For larger distances

> this relation is non linear.

> What my results show is that the results are highly non linear

> The question than pops up to what extend based on actual

> observation you can use z as an indication for distance.

> The same problems arise if you calculate H0 which is

> measured near the observer.

> The question is to what extend can you use the parameter

> 1/H0 in order to calculate the age of the Universe.

> What my results also show that the relation v = z * c

> is only true near the observer. For larger distances

> this relation is non linear.

> Nicolaas Vroomhttp://users.pandora.be/nicvroom/

Isn't this exactly what would be observed if the expansion of the

Universe was

due to the introduction of "new" space rather than the "stretching" of

existing

space?

Note: I am not saying that there is a larger Universe beyond our

horizon

that is "leaking" into ours. I am asking if an unrecognized process

may be

introducing new space between gravitationally bound structures larger

than

galaxies

Brad

Oct 11, 2011, 3:02:27 AM10/11/11

to

Nicolaas Vroom <nicolaa...@telenet.be> wrote in news:mt2.0-29733-

13182...@hydra.herts.ac.uk:

13182...@hydra.herts.ac.uk:

[...]

> What my results show is that the results are highly non linear

Yep.

> The question than pops up to what extend based on actual

> observation you can use z as an indication for distance.

It depends. Are we talking in 2011 with the cosmic distance ladder

firmly established and understood, or say 30 years ago when that wasn't

true?

In 2011 since we have the cosmological parameters well determined,

knowing the object's redshfit will give you its' distance.

> The same problems arise if you calculate H0 which is

> measured near the observer.

zuh?

The Hubble paramater is the textbook definition of something that's not

locally determined, as the Hubble flow is nonexistent for

gravitationally bound objects like everything from here until the edge

of the local group.

> The question is to what extend can you use the parameter

> 1/H0 in order to calculate the age of the Universe.

By itself? Rather minimally, as the Hubble constant alone does not

constrain the various other cosmological parameters that determine the

age of the universe.

> What my results also show that the relation v = z * c

> is only true near the observer. For larger distances

> this relation is non linear.

This is well known. Hubble's law only works out to about z=1.

> Space acceleration (Global and Local) is also discussed.

>

> What the results also show is that the more

> parameters are non zero in the Friedmann

> equation the more difficult it becomes to calculate

> the indivudual parameters.

This is well known.

Go read how the WMAP people figured it out.

http://lambda.gsfc.nasa.gov/product/map/dr4/pub_papers/sevenyear/cosmolo

gy/wmap_7yr_cosmology.pdf

Oct 11, 2011, 6:11:27 PM10/11/11

to

Le 10/10/11 16:26, brad a �crit :

> Isn't this exactly what would be observed if the expansion of the

> Universe was

> due to the introduction of "new" space rather than the "stretching" of

> existing

> space?

> Isn't this exactly what would be observed if the expansion of the

> Universe was

> due to the introduction of "new" space rather than the "stretching" of

> existing

> space?

Hi brad

The concept of a "space expansion" is absurd. Space can't expand since

it has no space to expand.

:-)

Space already occupies all space there is.

In a similar vein space can't "stretch" or "compress" or "condense".

This terms apply to objects in space but NOT to space itself.

Then, the question if space expands into a pre-existing space

or stretches to have more space than before is also absurd.

All this comes from a lack of understanding of basic philosophical

knowledge.

The only expanding universe is the known universe. As our scopes peer

farther and farther we can discern objects near the supposed "bang"...

and they look surprisingly old and very similar to objects we see in our

own neighborhood.

The same thing applies to "inflation" of space faster than

light...

If space "expands" faster than light, movement is impossible and all

objects have negative enrgy.

If you want to go from point A to point B you can't do it: Unless you

are a strange neutrino you can't go faster than light, and since

the expansion is separating point B from point A faster than light speed

you will never reach point B, it will have receeded faster than you can

ever run.

Conclusion: movement in such a universe is impossible. You can't go from

point A to point B no matter the distance between them.

Another unresolved paradox is the "cutout" point.

At which point does the space expansion stop objects from

moving apart?

We know objects like me or you do NOT expand, nor do the solar system,

nor our galaxy. At some point, however space expansion does separate

objects.

It is a pity that apparently ALL objects in the observable Universe

are connected to each other.

There are "rivers" of galaxies that flow between super clusters,

connecting them by thin filaments. Those filaments connect the largest

structures in the cosmos.

Those filaments should have been

destroyed by space expansion but apparently they aren't.

Why?

Maybe (just maybe) because there isn't any expansion at all.

I know that according to present day astronomy there is overwhelming

evidence for space expansion.

I am convinced that this interpretation is wrong because the arguments

above.

jacob

Oct 13, 2011, 2:25:03 AM10/13/11

to

On Oct 11, 6:11�pm, jacob navia <ja...@spamsink.net> wrote:

> Hi brad

>

> The concept of a "space expansion" is absurd. Space can't expand since

> it has no space to expand.

> Space already occupies all space there is.

Wheeler suggested a "quantum foam" as the ultimate spacetime

configuration.

More than one theorist believes that spacetime must have a structure.

What would

be the result (if this were so) if I added 1 quanta of space to the

Universe?

>

> In a similar vein space can't "stretch" or "compress" or "condense".

> This terms apply to objects in space but NOT to space itself.

So, then; What is a gravitational field?

> Then, the question if space expands into a pre-existing space

> or stretches to have more space than before is also absurd.

>

> All this comes from a lack of understanding of basic philosophical

> knowledge.

Okay, we all have our limitations.

> The only expanding universe is the known universe. As our scopes peer

> farther and farther we can discern objects near the supposed "bang"...

> and they look surprisingly old and very similar to objects we see in our

> own neighborhood.

According to the standard Cosmological model the fit is very good.

Ancient

galaxies are deficient in heavy elements because they only contain

first

generation stars.

> The same thing applies to "inflation" of space faster than

> light...

>

> If space "expands" faster than light, movement is impossible and all

> objects have negative enrgy.

>

> If you want to go from point A to point B you can't do it: Unless you

> are a strange neutrino you can't go faster than light, and since

> the expansion is separating point B from point A faster than light speed

> you will never reach point B, it will have receeded faster than you can

> ever run.

>

> Conclusion: movement in such a universe is impossible. You can't go from

> point A to point B no matter the distance between them.

This is actually a good argument for my original post; That the

expansion is due

to new space quanta being added to the Universe!

> Another unresolved paradox is the "cutout" point.

> At which point does the space expansion stop objects from

> moving apart?

Sorry, now you've lost me. Doesn't expansion cause separation?

> We know objects like me or you do NOT expand, nor do the solar system,

> nor our galaxy. At some point, however space expansion does separate

> objects.

> It is a pity that apparently ALL objects in the observable Universe

> are connected to each other.

> There are "rivers" of galaxies that flow between super clusters,

> connecting them by thin filaments. Those filaments connect the largest

> structures in the cosmos.

Ever look at the foam atop a glass of beer? Basically bubbles! The

large scale

structure, that you refer to, looks like huge bubbles (the voids) with

matter (galaxies, et al.)

occupying the surfaces of those bubbles. In addition, the expansion is

associated

with the voids, not the matter. Seems coincidental...hmm?

>

> Those filaments should have been

> destroyed by space expansion but apparently they aren't.

> Why?

See my analogy above.

Brad

Oct 14, 2011, 2:14:36 PM10/14/11

to

"eric gisse" <jowr.pi...@gmail.com> schreef in bericht

news:mt2.0-26635...@hydra.herts.ac.uk...

news:mt2.0-26635...@hydra.herts.ac.uk...

>> The question than pops up to what extend based on actual

>> observation you can use z as an indication for distance.

>

> It depends. Are we talking in 2011 with the cosmic distance ladder

> firmly established and understood, or say 30 years ago when that wasn't

> true?

>

> In 2011 since we have the cosmological parameters well determined,

> knowing the object's redshfit will give you its' distance.

>> observation you can use z as an indication for distance.

>

> It depends. Are we talking in 2011 with the cosmic distance ladder

> firmly established and understood, or say 30 years ago when that wasn't

> true?

>

> In 2011 since we have the cosmological parameters well determined,

> knowing the object's redshfit will give you its' distance.

That is the whole point.

If you look at document (2011) : Table1

http://arxiv.org/PS_cache/arxiv/pdf/1109/1109.4717v1.pdf

Only for 2 SN the Tully Fisher relation is used to establish distance.

The distance involved 22 Mpc and that is very short.

For 2 SN the redshift, z is used to calulate distance.

This distance is roughly 100 Mpc and that is not what we want.

What you want is to establish the relation between z versus distance

and both should be measured indepently.

The document Hubble Constant (2010) page 33

http://arxiv.org/PS_cache/arxiv/pdf/1004/1004.1856v1.pdf

shows that there are only 6 high quality SN measurements

available to calculate Hubble constant.

Figure 10 (page 77) shows distances based on TF relation

for distances until 100 pc versus v. (using v=c*z you can

back calculate z, which is observed)

My point is that those distances are too short to demonstrate

the non linearities involved.

To be more specific: To calculate the parameters C, labda and k.

In general you cannot calculate distance as a function of

using v=c*z (1) and v=H*d because (1) is only valid for small

distances.

>> The question is to what extend can you use the parameter

>> 1/H0 in order to calculate the age of the Universe.

>

> By itself? Rather minimally, as the Hubble constant alone does not

> constrain the various other cosmological parameters that determine the

> age of the universe.

That is my whole point of the document in question.

For an assumed age of 14 billion years you get for almost

any combination of the cosmological parameters C, labda and k

a different value of H0.

Does that mean that only those combinations are valid that result in

a 1/H0 value of 14 billion years ?

>> What my results also show that the relation v = z * c

>> is only true near the observer. For larger distances

>> this relation is non linear.

>

> This is well known. Hubble's law only works out to about z=1.

What exactly do you mean with: works out.

Does this mean to calculate distances ?

Does this mean to calculate age of Universe ?

specific IMO this is not possible.

Nicolaas Vroom

http://users.pandora.be/nicvroom/

[Mod. note: please DO NOT link to the arXiv cache, but direct to the

article of interest -- mjh]

Oct 15, 2011, 2:49:26 AM10/15/11

to

In article <mt2.0-21457...@hydra.herts.ac.uk>, Nicolaas Vroom

measures the distance and z is easily observed.

> The document Hubble Constant (2010) page 33

> http://arxiv.org/PS_cache/arxiv/pdf/1004/1004.1856v1.pdf

> shows that there are only 6 high quality SN measurements

> available to calculate Hubble constant.

>

> Figure 10 (page 77) shows distances based on TF relation

> for distances until 100 pc versus v. (using v=c*z you can

> back calculate z, which is observed)

>

> My point is that those distances are too short to demonstrate

> the non linearities involved.

> To be more specific: To calculate the parameters C, labda and k.

The idea is this: the Hubble constant is calculated at a redshift which

is large enough so that the cosmological redshift dominates over

peculiar motion, but small enough so that the relationship is still

linear. Objects at larger redshift are used for the non-linearity. But

the non-linearity can be observed even if the Hubble constant is

completely unknown.

> That is my whole point of the document in question.

> For an assumed age of 14 billion years you get for almost

> any combination of the cosmological parameters C, labda and k

> a different value of H0.

> Does that mean that only those combinations are valid that result in

> a 1/H0 value of 14 billion years ?

Yes, IF you know both the age and the Hubble constant. In practice, it

is almost the other way around: we now know the Hubble constant and the

other parameters quite well and the age is calculated, not assumed nor

measured "directly".

<nicolaa...@telenet.be> writes:

> > In 2011 since we have the cosmological parameters well determined,

> > knowing the object's redshfit will give you its' distance.

>

> That is the whole point.

> If you look at document (2011) : Table1

> http://arxiv.org/PS_cache/arxiv/pdf/1109/1109.4717v1.pdf

> Only for 2 SN the Tully Fisher relation is used to establish distance.

> The distance involved 22 Mpc and that is very short.

> For 2 SN the redshift, z is used to calulate distance.

> This distance is roughly 100 Mpc and that is not what we want.

>

> What you want is to establish the relation between z versus distance

> and both should be measured indepently.

The whole idea of standard candles is that the apparent magnitude
> > In 2011 since we have the cosmological parameters well determined,

> > knowing the object's redshfit will give you its' distance.

>

> That is the whole point.

> If you look at document (2011) : Table1

> http://arxiv.org/PS_cache/arxiv/pdf/1109/1109.4717v1.pdf

> Only for 2 SN the Tully Fisher relation is used to establish distance.

> The distance involved 22 Mpc and that is very short.

> For 2 SN the redshift, z is used to calulate distance.

> This distance is roughly 100 Mpc and that is not what we want.

>

> What you want is to establish the relation between z versus distance

> and both should be measured indepently.

measures the distance and z is easily observed.

> The document Hubble Constant (2010) page 33

> http://arxiv.org/PS_cache/arxiv/pdf/1004/1004.1856v1.pdf

> shows that there are only 6 high quality SN measurements

> available to calculate Hubble constant.

>

> Figure 10 (page 77) shows distances based on TF relation

> for distances until 100 pc versus v. (using v=c*z you can

> back calculate z, which is observed)

>

> My point is that those distances are too short to demonstrate

> the non linearities involved.

> To be more specific: To calculate the parameters C, labda and k.

is large enough so that the cosmological redshift dominates over

peculiar motion, but small enough so that the relationship is still

linear. Objects at larger redshift are used for the non-linearity. But

the non-linearity can be observed even if the Hubble constant is

completely unknown.

> That is my whole point of the document in question.

> For an assumed age of 14 billion years you get for almost

> any combination of the cosmological parameters C, labda and k

> a different value of H0.

> Does that mean that only those combinations are valid that result in

> a 1/H0 value of 14 billion years ?

is almost the other way around: we now know the Hubble constant and the

other parameters quite well and the age is calculated, not assumed nor

measured "directly".

Oct 15, 2011, 2:52:33 AM10/15/11

to

Nicolaas Vroom <nicolaa...@telenet.be> wrote in news:mt2.0-21457-

13186...@hydra.herts.ac.uk:

> "eric gisse" <jowr.pi...@gmail.com> schreef in bericht

> news:mt2.0-26635...@hydra.herts.ac.uk...

>> Nicolaas Vroom <nicolaa...@telenet.be> wrote in news:mt2.0-29733-

>> 13182...@hydra.herts.ac.uk:

>>

>>> The question than pops up to what extend based on actual

>>> observation you can use z as an indication for distance.

>>

>> It depends. Are we talking in 2011 with the cosmic distance ladder

>> firmly established and understood, or say 30 years ago when that

wasn't

>> true?

>>

>> In 2011 since we have the cosmological parameters well determined,

>> knowing the object's redshfit will give you its' distance.

>

> That is the whole point.

> If you look at document (2011) : Table1

> http://arxiv.org/PS_cache/arxiv/pdf/1109/1109.4717v1.pdf

> Only for 2 SN the Tully Fisher relation is used to establish distance.

> The distance involved 22 Mpc and that is very short.

> For 2 SN the redshift, z is used to calulate distance.

> This distance is roughly 100 Mpc and that is not what we want.

>

> What you want is to establish the relation between z versus distance

> and both should be measured indepently.

www.google.com "cosmic distance ladder"

I'll gladly discuss the subject but I'm not going to teach it.

>

> The document Hubble Constant (2010) page 33

> http://arxiv.org/PS_cache/arxiv/pdf/1004/1004.1856v1.pdf

Why do people keep posting links to the pdf?

Regardless, I've read this before. Its' a decent paper on the subject.

> shows that there are only 6 high quality SN measurements

> available to calculate Hubble constant.

And where does it say that? I wonder how you imagine we can get such a

small systematic error in H_0 with a sample size of six.

>

> Figure 10 (page 77) shows distances based on TF relation

> for distances until 100 pc versus v. (using v=c*z you can

> back calculate z, which is observed)

>

> My point is that those distances are too short to demonstrate

> the non linearities involved.

> To be more specific: To calculate the parameters C, labda and k.

>

> In general you cannot calculate distance as a function of

> using v=c*z (1) and v=H*d because (1) is only valid for small

> distances.

Welcome to the obvious problem of the past 40 years of cosmology.

The Hubble constant can be discerned through a few ways but currently

the best non-model dependent answer is only known to about 5% and that's

a factor of 3 better than we were able to say 15 years ago.

If you allow model dependent answers ala concordance cosmology via WMAP

and other observations (Komatsu, et. al. have written about this a time

or twenty) then the answer is known even better.

At the moment the answers match within their error margins so I'm not

abundantly concerned.

You just cited an 80 page paper, which I doubt you've fully much less

partially read, which discusses this in intricate detail.

>

>>> The question is to what extend can you use the parameter

>>> 1/H0 in order to calculate the age of the Universe.

>>

>> By itself? Rather minimally, as the Hubble constant alone does not

>> constrain the various other cosmological parameters that determine

the

>> age of the universe.

>

> That is my whole point of the document in question.

As far as I'm able to determine you are looking at an individual data

point in the vacuum while ignoring how it fits in with a far, far larger

body of work.

Read the small words:

The hubble constant only makes sense in 2011 when you look at the big

picture. Look at the big picture. Stop screwing around with the small

picture.

> For an assumed age of 14 billion years you get for almost

> any combination of the cosmological parameters C, labda and k

> a different value of H0.

> Does that mean that only those combinations are valid that result in

> a 1/H0 value of 14 billion years ?

Read the literature, as my answer won't mean anything to you.

http://lambda.gsfc.nasa.gov/product/map/dr4/pub_papers/sevenyear/cosmolo

gy/wmap_7yr_cosmology.pdf

>

>>> What my results also show that the relation v = z * c

>>> is only true near the observer. For larger distances

>>> this relation is non linear.

>>

>> This is well known. Hubble's law only works out to about z=1.

> What exactly do you mean with: works out.

Hubble's law is an approximation. This is well known.

> Does this mean to calculate distances ?

> Does this mean to calculate age of Universe ?

> specific IMO this is not possible.

If you say so.

13186...@hydra.herts.ac.uk:

> "eric gisse" <jowr.pi...@gmail.com> schreef in bericht

> news:mt2.0-26635...@hydra.herts.ac.uk...

>> Nicolaas Vroom <nicolaa...@telenet.be> wrote in news:mt2.0-29733-

>> 13182...@hydra.herts.ac.uk:

>>

>>> The question than pops up to what extend based on actual

>>> observation you can use z as an indication for distance.

>>

>> It depends. Are we talking in 2011 with the cosmic distance ladder

>> firmly established and understood, or say 30 years ago when that

wasn't

>> true?

>>

>> In 2011 since we have the cosmological parameters well determined,

>> knowing the object's redshfit will give you its' distance.

>

> That is the whole point.

> If you look at document (2011) : Table1

> http://arxiv.org/PS_cache/arxiv/pdf/1109/1109.4717v1.pdf

> Only for 2 SN the Tully Fisher relation is used to establish distance.

> The distance involved 22 Mpc and that is very short.

> For 2 SN the redshift, z is used to calulate distance.

> This distance is roughly 100 Mpc and that is not what we want.

>

> What you want is to establish the relation between z versus distance

> and both should be measured indepently.

I'll gladly discuss the subject but I'm not going to teach it.

>

> The document Hubble Constant (2010) page 33

> http://arxiv.org/PS_cache/arxiv/pdf/1004/1004.1856v1.pdf

Regardless, I've read this before. Its' a decent paper on the subject.

> shows that there are only 6 high quality SN measurements

> available to calculate Hubble constant.

small systematic error in H_0 with a sample size of six.

>

> Figure 10 (page 77) shows distances based on TF relation

> for distances until 100 pc versus v. (using v=c*z you can

> back calculate z, which is observed)

>

> My point is that those distances are too short to demonstrate

> the non linearities involved.

> To be more specific: To calculate the parameters C, labda and k.

>

> In general you cannot calculate distance as a function of

> using v=c*z (1) and v=H*d because (1) is only valid for small

> distances.

The Hubble constant can be discerned through a few ways but currently

the best non-model dependent answer is only known to about 5% and that's

a factor of 3 better than we were able to say 15 years ago.

If you allow model dependent answers ala concordance cosmology via WMAP

and other observations (Komatsu, et. al. have written about this a time

or twenty) then the answer is known even better.

At the moment the answers match within their error margins so I'm not

abundantly concerned.

You just cited an 80 page paper, which I doubt you've fully much less

partially read, which discusses this in intricate detail.

>

>>> The question is to what extend can you use the parameter

>>> 1/H0 in order to calculate the age of the Universe.

>>

>> By itself? Rather minimally, as the Hubble constant alone does not

>> constrain the various other cosmological parameters that determine

the

>> age of the universe.

>

> That is my whole point of the document in question.

point in the vacuum while ignoring how it fits in with a far, far larger

body of work.

Read the small words:

The hubble constant only makes sense in 2011 when you look at the big

picture. Look at the big picture. Stop screwing around with the small

picture.

> For an assumed age of 14 billion years you get for almost

> any combination of the cosmological parameters C, labda and k

> a different value of H0.

> Does that mean that only those combinations are valid that result in

> a 1/H0 value of 14 billion years ?

http://lambda.gsfc.nasa.gov/product/map/dr4/pub_papers/sevenyear/cosmolo

gy/wmap_7yr_cosmology.pdf

>

>>> What my results also show that the relation v = z * c

>>> is only true near the observer. For larger distances

>>> this relation is non linear.

>>

>> This is well known. Hubble's law only works out to about z=1.

> What exactly do you mean with: works out.

> Does this mean to calculate distances ?

> Does this mean to calculate age of Universe ?

> specific IMO this is not possible.

Oct 24, 2011, 9:53:00 AM10/24/11

to

"Phillip Helbig---undress to reply" <hel...@astro.multiCLOTHESvax.de>

schreef in bericht news:mt2.0-23482...@hydra.herts.ac.uk...

>> My point is that those distances are too short to demonstrate

>> the non linearities involved.

>> To be more specific: To calculate the parameters C, labda and k.

>

> The idea is this: (1) the Hubble constant is calculated at a redshift

> (3) But the non-linearity can be observed even if the Hubble

> constant is completely unknown.

I agree with (1)

The issues (2) and (3) are discussed in the following document 1

from 2003:

http://arxiv.org/PS_cache/astro-ph/pdf/0303/0303428v1.pdf

Fig 4 of that document demonstrates this non-linearity.

The same and even more data is shown the document 2 from 2011:

http://arxiv.org/PS_cache/arxiv/pdf/1104/1104.1443v1.pdf

at Fig 5 page 32.

Document 1 shows the relation between z and distance

when you assume z is linear scale.

Document 2 shows the relation between z and magtitude

Using the Friedmann equation I have tried to calculate

the parameters C, labda and k based on those two documents.

The results are at

http://users.telenet.be/nicvroom/friedmann's%20equation.htm#Q6

I have added a new question number 6.

The section shows two figures: 11 and 12.

Figure 11 shows the relation between z and magtitude.

The black line is the observed curve and is a copy of document 2.

Document 2 is the source document/data of also figure 12.

Figure 12 shows the relation between z and distance.

The black line is in good agreement with document 1.

Specific what Figure 12 shows is that the shape of the observed

curve is different as the shape of all calculated values for different

combinations of the parameters labda.

The parameter L has no direct influence on this shape.

What this means is that it is not possible to calculate the parameters

C, Labda and k based on the observations.

One possible explanation could be that for higher values of z

the ralation between magtitude and distance is different then

for low values of z

Nicolaas Vroom

http://users.telenet.be/nicvroom/

schreef in bericht news:mt2.0-23482...@hydra.herts.ac.uk...

> In article <mt2.0-21457...@hydra.herts.ac.uk>, Nicolaas Vroom

> <nicolaa...@telenet.be> writes:

>

>> What you want is to establish the relation between z versus distance

>> and both should be measured indepently.

>

> The whole idea of standard candles is that the apparent magnitude

> measures the distance and z is easily observed.

I agree
> <nicolaa...@telenet.be> writes:

>

>> What you want is to establish the relation between z versus distance

>> and both should be measured indepently.

>

> The whole idea of standard candles is that the apparent magnitude

> measures the distance and z is easily observed.

>> My point is that those distances are too short to demonstrate

>> the non linearities involved.

>> To be more specific: To calculate the parameters C, labda and k.

>

> which

> is large enough so that the cosmological redshift dominates over

> peculiar motion, but small enough so that the relationship is still

> linear. (2) Objects at larger redshift are used for the non-linearity.
> is large enough so that the cosmological redshift dominates over

> peculiar motion, but small enough so that the relationship is still

> (3) But the non-linearity can be observed even if the Hubble

> constant is completely unknown.

I agree with (1)

The issues (2) and (3) are discussed in the following document 1

from 2003:

http://arxiv.org/PS_cache/astro-ph/pdf/0303/0303428v1.pdf

Fig 4 of that document demonstrates this non-linearity.

The same and even more data is shown the document 2 from 2011:

http://arxiv.org/PS_cache/arxiv/pdf/1104/1104.1443v1.pdf

at Fig 5 page 32.

Document 1 shows the relation between z and distance

when you assume z is linear scale.

Document 2 shows the relation between z and magtitude

Using the Friedmann equation I have tried to calculate

the parameters C, labda and k based on those two documents.

The results are at

http://users.telenet.be/nicvroom/friedmann's%20equation.htm#Q6

I have added a new question number 6.

The section shows two figures: 11 and 12.

Figure 11 shows the relation between z and magtitude.

The black line is the observed curve and is a copy of document 2.

Document 2 is the source document/data of also figure 12.

Figure 12 shows the relation between z and distance.

The black line is in good agreement with document 1.

Specific what Figure 12 shows is that the shape of the observed

curve is different as the shape of all calculated values for different

combinations of the parameters labda.

The parameter L has no direct influence on this shape.

What this means is that it is not possible to calculate the parameters

C, Labda and k based on the observations.

One possible explanation could be that for higher values of z

the ralation between magtitude and distance is different then

for low values of z

Nicolaas Vroom

http://users.telenet.be/nicvroom/

Oct 25, 2011, 2:39:43 AM10/25/11

to

In article <mt2.0-18379...@hydra.herts.ac.uk>, Nicolaas Vroom

"issue" with it; it's standard textbook stuff.

Please check out this paper:

@ARTICLE {SRefsdalSdL67a,

AUTHOR = "Sjur Refsdal and Rolf Stabell and

F. G. de Lange",

TITLE = "Numerical calculations on relativistic

cosmological models",

JOURNAL = MRAS,

YEAR = "1967",

VOLUME = "71",

PAGES = "143"}

They use sigma and q instead of lambda and Omega, but the relationship

is simple (sigma = Omega/2 and lambda = sigma - q) and show how these

parameters can be used to calculate various observable quantities as a

function of redshift over a large redshift range into the very

non-linear regime. If one has good observational, it is easy to

determine the parameters via curve-fitting. All of the difficulties,

debate, discussion, problems and current work is involved in getting

good observational data, not interpreting them.

<nicolaa...@telenet.be> writes:

> > The idea is this: (1) the Hubble constant is calculated at a redshift

> > which

> > is large enough so that the cosmological redshift dominates over

> > peculiar motion, but small enough so that the relationship is still

> > linear. (2) Objects at larger redshift are used for the non-linearity.

> > (3) But the non-linearity can be observed even if the Hubble

> > constant is completely unknown.

>

> I agree with (1)

> The issues (2) and (3) are discussed in the following document 1

> from 2003:

> http://arxiv.org/PS_cache/astro-ph/pdf/0303/0303428v1.pdf

> Fig 4 of that document demonstrates this non-linearity.

This non-linearity has been known for almost 100 years. There is no
> > The idea is this: (1) the Hubble constant is calculated at a redshift

> > which

> > is large enough so that the cosmological redshift dominates over

> > peculiar motion, but small enough so that the relationship is still

> > linear. (2) Objects at larger redshift are used for the non-linearity.

> > (3) But the non-linearity can be observed even if the Hubble

> > constant is completely unknown.

>

> I agree with (1)

> The issues (2) and (3) are discussed in the following document 1

> from 2003:

> http://arxiv.org/PS_cache/astro-ph/pdf/0303/0303428v1.pdf

> Fig 4 of that document demonstrates this non-linearity.

"issue" with it; it's standard textbook stuff.

Please check out this paper:

@ARTICLE {SRefsdalSdL67a,

AUTHOR = "Sjur Refsdal and Rolf Stabell and

F. G. de Lange",

TITLE = "Numerical calculations on relativistic

cosmological models",

JOURNAL = MRAS,

YEAR = "1967",

VOLUME = "71",

PAGES = "143"}

They use sigma and q instead of lambda and Omega, but the relationship

is simple (sigma = Omega/2 and lambda = sigma - q) and show how these

parameters can be used to calculate various observable quantities as a

function of redshift over a large redshift range into the very

non-linear regime. If one has good observational, it is easy to

determine the parameters via curve-fitting. All of the difficulties,

debate, discussion, problems and current work is involved in getting

good observational data, not interpreting them.

Nov 12, 2011, 12:18:40 PM11/12/11

to

"Phillip Helbig---undress to reply" <hel...@astro.multiCLOTHESvax.de>

schreef in bericht news:mt2.0-15665...@hydra.herts.ac.uk...
>

> This non-linearity has been known for almost 100 years. There is no

> "issue" with it; it's standard textbook stuff.

>

> Please check out this paper:

>

> @ARTICLE {SRefsdalSdL67a,

> AUTHOR = "Sjur Refsdal and Rolf Stabell and

> F. G. de Lange",

> TITLE = "Numerical calculations on relativistic

> cosmological models",

> JOURNAL = MRAS,

> YEAR = "1967",

> VOLUME = "71",

> PAGES = "143"}

>

> They use sigma and q instead of lambda and Omega, but the relationship

> is simple (sigma = Omega/2 and lambda = sigma - q) and show how these

> parameters can be used to calculate various observable quantities as a

> function of redshift over a large redshift range into the very

> non-linear regime. If one has good observational, it is easy to

> determine the parameters via curve-fitting. All of the difficulties,

> debate, discussion, problems and current work is involved in getting

> good observational data, not interpreting them.

>

The above mentioned document is online available at:
> This non-linearity has been known for almost 100 years. There is no

> "issue" with it; it's standard textbook stuff.

>

> Please check out this paper:

>

> @ARTICLE {SRefsdalSdL67a,

> AUTHOR = "Sjur Refsdal and Rolf Stabell and

> F. G. de Lange",

> TITLE = "Numerical calculations on relativistic

> cosmological models",

> JOURNAL = MRAS,

> YEAR = "1967",

> VOLUME = "71",

> PAGES = "143"}

>

> They use sigma and q instead of lambda and Omega, but the relationship

> is simple (sigma = Omega/2 and lambda = sigma - q) and show how these

> parameters can be used to calculate various observable quantities as a

> function of redshift over a large redshift range into the very

> non-linear regime. If one has good observational, it is easy to

> determine the parameters via curve-fitting. All of the difficulties,

> debate, discussion, problems and current work is involved in getting

> good observational data, not interpreting them.

>

http://adsabs.harvard.edu/abs/1967MmRAS..71..143R

I have a problem with the parameter q.

The problem is that parameter is relative easy to calculate

using the Friedmann equation but difficult to calculate

using observations. Because the parameter is a function of:

distance, speed and acceleration.

Specific acceleration of a galaxy is difficult to observe.

See also:

http://users.telenet.be/nicvroom/friedmann's%20equation.htm#Q9

The most accurate observed function between magtitude

and z is available at:

http://arxiv.org/PS_cache/arxiv/pdf/1104/1104.1443v1.pdf

See figure 5 at page 32.

My simulations show the relation between x and z.

The issue is the relation between magtitude and x.

In order to calculate the magtitude i used the relation:

F = L / 4 pi d^2.

When you do that there is a mismatch between simulation

and observation for the larger z values.

See also:

http://users.telenet.be/nicvroom/friedmann's%20equation.htm#Q7

In order to try to get a better fit I tried: F = L / 4 pi d^3

The result is a better match for higher values of z.

Physical this means that galaxies further away are weaker as

expected.

I also tried: F = L / 4 pi d^2*(1+d).

This gives the best match for Labda = 0.05 and k=0

I also tried different ages for the Universe (28 and 42)

In fact that has no influence. See question 8

That raises the question if it is very difficult to calculate

the age of the Universe based observations of

the parameters z and m (or d)

Nicolaas Vroom

http://users.telenet.be/nicvroom/

Nov 14, 2011, 4:37:50 PM11/14/11

to

In article <mt2.0-18809...@hydra.herts.ac.uk>, Nicolaas Vroom

directly. If once assumes that the Friedmann-Lemaitre equation holds,

then it doesn't matter which parameters one uses since the conversions

are clear. If not, then you still have essentially measurements of

redshift, brightness and angular size---you still haven't measured

anything of interest "directly" but need a(nother) framework in which to

interpret the observations.

In other words, since q is Omega/2 - lambda, it doesn't matter if I

measure q or measure Omega and lambda and calculate q. In particular,

one can't say that the former is worse since one can't "directly"

measure q; one can't "directly" measure Omega and lambda either.

> Specific acceleration of a galaxy is difficult to observe.

See above.

> The most accurate observed function between magtitude

> and z is available at:

> http://arxiv.org/PS_cache/arxiv/pdf/1104/1104.1443v1.pdf

> See figure 5 at page 32.

> My simulations show the relation between x and z.

> The issue is the relation between magtitude and x.

> In order to calculate the magtitude i used the relation:

> F = L / 4 pi d^2.

What is d? It has to be the luminosity distance. Also, the equation

applies only for bolometric luminosity---not much use in practice. Look

into the K-correction, and also evolutionary corrections if the

luminosity of your objects changes with time.

> In order to try to get a better fit I tried: F = L / 4 pi d^3

> The result is a better match for higher values of z.

A wrong equation coincidentally cancels another known effect.

> Physical this means that galaxies further away are weaker as

> expected.

> I also tried: F = L / 4 pi d^2*(1+d).

> This gives the best match for Labda = 0.05 and k=0

Ditto.

> I also tried different ages for the Universe (28 and 42)

> In fact that has no influence. See question 8

> That raises the question if it is very difficult to calculate

> the age of the Universe based observations of

> the parameters z and m (or d)

No, it is trivial and has been known since the 1920s. Again, the

problem is getting good observations and interpreting them directly.

The theoretical background is textbook stuff.

<nicolaa...@telenet.be> writes:

> The above mentioned document is online available at:

> http://adsabs.harvard.edu/abs/1967MmRAS..71..143R

> I have a problem with the parameter q.

> The problem is that parameter is relative easy to calculate

> using the Friedmann equation but difficult to calculate

> using observations. Because the parameter is a function of:

> distance, speed and acceleration.

No-one measures q "directly". For that matter, no-one measures velocity
> The above mentioned document is online available at:

> http://adsabs.harvard.edu/abs/1967MmRAS..71..143R

> I have a problem with the parameter q.

> The problem is that parameter is relative easy to calculate

> using the Friedmann equation but difficult to calculate

> using observations. Because the parameter is a function of:

> distance, speed and acceleration.

directly. If once assumes that the Friedmann-Lemaitre equation holds,

then it doesn't matter which parameters one uses since the conversions

are clear. If not, then you still have essentially measurements of

redshift, brightness and angular size---you still haven't measured

anything of interest "directly" but need a(nother) framework in which to

interpret the observations.

In other words, since q is Omega/2 - lambda, it doesn't matter if I

measure q or measure Omega and lambda and calculate q. In particular,

one can't say that the former is worse since one can't "directly"

measure q; one can't "directly" measure Omega and lambda either.

> Specific acceleration of a galaxy is difficult to observe.

> The most accurate observed function between magtitude

> and z is available at:

> http://arxiv.org/PS_cache/arxiv/pdf/1104/1104.1443v1.pdf

> See figure 5 at page 32.

> My simulations show the relation between x and z.

> The issue is the relation between magtitude and x.

> In order to calculate the magtitude i used the relation:

> F = L / 4 pi d^2.

applies only for bolometric luminosity---not much use in practice. Look

into the K-correction, and also evolutionary corrections if the

luminosity of your objects changes with time.

> In order to try to get a better fit I tried: F = L / 4 pi d^3

> The result is a better match for higher values of z.

> Physical this means that galaxies further away are weaker as

> expected.

> I also tried: F = L / 4 pi d^2*(1+d).

> This gives the best match for Labda = 0.05 and k=0

> I also tried different ages for the Universe (28 and 42)

> In fact that has no influence. See question 8

> That raises the question if it is very difficult to calculate

> the age of the Universe based observations of

> the parameters z and m (or d)

problem is getting good observations and interpreting them directly.

The theoretical background is textbook stuff.

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