(1) Wrong and (2) wrong.

First of all, the article on redshift in Wikipedia seems to be in error. How would we know what the "wavelength" is supposed to be? We don't expect to see a particular wavelength and then, upon seeing a longer one, say that light has been redshifted. This completely misses the way redshifts are actually measured, which has to do with the shift in spectral lines of various elements or elemental transitions that are visible when light is spread into a spectrum.

As to your denial of Tonyman's assertion that the universe is expanding and that we have measured it, I believe you have swept quite a bit of confirming evidence under the rug. Cepheid variable stars have confirmed that the above-mentioned spectral shifts are proportional to the distance to the object. We also know from terrestrial experiments that spectral shifts result from objects that are (significantly) moving relative to each other. Specifically, redshift implies objects moving away from each other. Now, why would more distant objects be moving away from us at greater speeds? If you have a more perfect explanation than "space is expanding," I'd like to hear it.

And then we have all of the Ia supernova data that is consistent with time dilation effects that can only be explained in an expanding universe.... Unless, again, you can provide some better explanation that conforms so well to the observations.

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Everyone is entitled to his own opinion, but not his own facts.

Here it is you cougar the mistaken one.

The interpretation of the SNe Ia data has created a bubble sadly lacking rational exuberance. Indeed it has caused an acceleration capable of wreaking such havoc that astronomers have ended up defaulting on physical laws: enter dark energy and nonbaryonic DM (new physics). That scarcely sounds like rational exuberance.

The limits of your understanding on the subject of SNe Ia light curves and redshift z is exemplified here. This is the origin of your misunderstanding of the data.



Your arguments are nothing but a paper tiger.


Case closed...NOT


Coldcreation, aka DVDjHex

I would respond to your little diatribe, but I can't find any substance to it.

__________________
Everyone is entitled to his own opinion, but not his own facts.

This is interesting. Indeed what is being measured is redshift z, not motion (in current terminology redshift is not a Doppler effect. It is thus not a measurment of real motion).

Clearly the interpretation of what causes redshift is of utmost importance. An erroneous interpretation throws off the entire model (i.e., it will render the model false).

In order to test the hypothesis that space is expanding (causing redshift) a certain number of predictions had to be made. As it turns out, recent observations (viz SNe Ia data) have contradicted (rendered untenable) the interpretation that space is expanding.

The SNe Ia observational results were not the anticipated circumstances to encourage a direct confrontation with realities, least of all with the realities of the Friedmann or inflationary world-views. In other words, with one erroneous interpretation, modern cosmology has surrounded itself with myth, evaded the past, and thus eluded the future.


The new force attributed to lambda (dark energy) is yet another instance of theoretical exceptionalism—so often the object of complaints by steady state theorists and others who attempts to penetrate the cosmology market. For the most part, the term dark—aside from possessing an intriguing dimension of belief—is really used as a means of systemic protectionism.






Coldcreation

Here we go again. You bring this up, even though you can't finish a single thread where you try to defend the idea.
Fortunately, the results were exactly the sort that standard cosmology was set up to measure. So, regardless of whether or not the majority of scientists expected the results, they already had a framework within the family of models that make up the standard theory in which to make the observations in to measurements of the parameters of the standard theory. Indeed, the SNIa results were about as direct a confrontation with reality as astronomy gets!
It would be an exception if not for the fact that it is a parameter that can be measured. It is hardly exceptional to admit of theoretical parameters that have actual empirical measurements.

removed double post

Hello KK, it's been a while.

Two points. I did not bring up the topic here. It was brought up in post #31. I merely attempt set the record straight.

You write that I "can't finish a single thread..."

Every post I make regarding the SNe Ia data finishes the thread, but somehow they just keep on going. I argue the SNe data rules out expansion. For me the case is closed, unless compelling evidence is found that SNe Ia are NOT good standard candles, or that independent studies confirm the existence of nonbaryonic DM and DE and thus do not contradict or render irrelevant Hubble's law (hint: we'll be waiting for indefinately, I am sure).

On this we are in agreement.






Coldcreation

Let's try to get this back to the original topic.

There are several things being measured whenever redshift is used cosmologically. One is the redshift relative to an expected spectrum. One is a measure of distance.

The Hubble Constant is something that, in the standard model, is merely the current value of the first derivative of a function that is part of distance determinations over time.

The observation of redshift and distances relatively near to our position measures the Hubble constant. By looking further away, we measure the second and third derivatives of the function.

So even if we don't believe in dark energy, we can believe in the Hubble "law" and in the measured second and third derivatives.

A scientific theory of the universe must explain these observations. The standard model does so fairly well.

Any discussion of the "current universe", if it is going to be scientific, must also address these observations. That is, any discussion of the "current universe" must at least explain why it doesn't behave in the way that everything that we do observe behaves.

I haven't seen every cat, yet I have a reasonable approach to cats based on the cats I have already seen.

It seems like this would be BIG news to all astronomers and cosmologists. What extraordinary evidence can you point to that overturns this finding that has been held for the past 70 years?

__________________
Everyone is entitled to his own opinion, but not his own facts.

Where have you been?

...Just a few of the numerous publications regarding the SNe data...


The SNe Ia redshift z and light curves data speaks for itself: that is extraordinary evidence.

The SNe Ia observations in the late 90's were interpreted as a relatively recent acceleration of the expansion, and formed the basis of the Lamdba-CDM model that is currently most popular.

What is it about the SNe Ia observations that you think means that redshift is not caused by recession velocity?

Whether the SNe Ia interpretation means the expansion is accelerating or not, how does this change the overall interpretation that redshifts where z > 0.1 represent cosmological expansion, and that redshifts around z = ~1.46 represent a recession velocity of c?

One of the tests designed to determine whether expansion was real or not was based on the deceleration parameter, on the Hubble law. Of the three possible solutions (called the Friedmann models) not one was able to withstand the confrontation with observations. Predictions failed, and for a variety of reasons. But the message was clear, and was reflected not just in the press of the times.

According to the Hubble law there is a very specific relation between redshift and distance. The SNe Ia appear 20 - 25% further than would be expected according to the so-called Law. We can now constat that the Hubble law is no law at all, that the principle test for expansion (to conform to the Friedmann models/the FLRW metric) failed.

And ultimately, something fake, man-made, artificial, had to be glued on the the late standard model, and in the process, created an altogether new standard model laced with dark bunk. Without the bunk, recession could be claimed valid. And with the bunk it even worse, since the bunk itself could not be explained in physical terms.

The new discovery is important. It definitively deprives modern cosmology the beauty, the symmetry it so desperately neded. It brings back all the problems inherent in its foundation (the ones that inflation was supposed to solve) except for one: the artificial fine-tuning problem. There simply is no fine-tuning anymore.

The most beautiful result of the standard Friedmann world models with a one-to-one relation between the density of the cosmos and its spatial curvature has evaporated. In short, the observations show that the only law upon which the big bang was founded is violated progressively as we look deeper into space, or further back in time.

CC

Frankly, speedfreek, this poster is simply a liar.

How in the world is accusing me of being a liar (of misleading or hiding the truth deliberately, of supplying false information purposely in order to deceive posters at ATM) going to advance this discussion?

It is as nonsensical as deserving of ridicule...

If you have to attack something do so to the facts, interpretations and/or opinions that I present rather than the person presenting them.

Thanks in advance.

Coldcreation

Is that 20 - 25% further away across the whole range of distances then? Or does the discrepancy get larger, the closer we look?

The deviation from linearity (predicted by the Hubble law, and inflation which predicted a flat universe) is larger at greater distance.

Indeed the Hubble law states that redshift z of the emitting object is proportional to its distance. It was classified as a law because it was thought to hold at all distances. As it turned out, the SNe Ia appear up to 25% further than would be expected according to that so-called law (it turns out too that it is not a law).

So the idea that expansion is real has been dealt a serious blow (a fatal blow in fact) since the 'law' upon which it was based, and the predictions based on the Friedmann models have simply not passed empirical tests.

Only when vast quantities of dark energy and dark matter are added to the mix does something resembling the old standard model emerge.

In effect, the SNe Ia data excluded the possibility that the universe is expanding according to the Hubble Law—unless, by some natural wonder or freakish spectacle, gravitational attraction is perfectly balanced with the repulsion. But then no one can explain why the universe has not always been stable and perfectly balanced, as Einstein imagined:




Coldcreation

Now excuse my confusion here.. you originally said the SNe Ia were 20-25% further away (fainter) than predicted. I asked over what range. Now you say the deviation is greater at larger distances - up to 25%. So are the closest SNe Ia 20% further away? Is the deviation rising from 20-25% or from 0-25%?

But does the data exclude the possibility that the universe is expanding at tall, or only exclude it expanding according to the Hubble Law - a law based on much closer (more local) observations? How much do the SNe Ia deviate within the distances that Hubble was looking at?

Do these observations preclude expansion, or simple require an adjustment to the model?