Red Shift Reliability. What verifies Red Shift method?

[mindopener9]

Hi, I'm new, again, to this message board. I was a member before under a different name, but anyway...<br />Question for experts, please. What independent verification method was/ or is used to verify the method of Red Shifts for determining distances and recessional velocities? Cepheid variables I'm already familiar with. What my question is meant to convey is, How do scientists really know that their Doppler Red (or Blue) Shifts really work exactly the way we are all told that they do?<br />I have been scouring the web for proof myself and have only come up with a lot of naysayers and crackpot theories that claim to have the "Right Answers" to explain it all that flies in the face of the Big Bang theory and a lot of other "accepted" cosmology. <br />I thought about photographic evidence, but decided that 160 years of astronomical photographs do not allow enough time to actually see objects getting smaller as they recede from us. So what other method IS used to verify the reliability of Doppler Red Shifts?<br />Just in case, I have a few other Big Questions regarding other subjects near and dear to "accepted" physicists hearts & minds.<br />I guess, since accelerating Cosmic Expansion and Dark Energy depend on a reliable interpretation of Red Shifts and "should" take into account any and all possible variables, mine isn't a stupid question. A lot of scientists are working on these questions and receive a lot of funding to study these topics, so, as a taxpayer, I'd like to know just how firm these foundations we should trust in really are. <div class="Discussion_UserSignature"> We must progress and expand, or we will stagnate and die. </div>

 

[kmarinas86]

Guilt by association.

 

[SpeedFreek]

Apart from the Cepheid variables, another clue is the time-dilation of Type Ia Supernovae at differing redshifts, where those supernovae are considered to be "standard candles".<br /><br />But let's not confuse Doppler shift with <i>cosmological</i> redshift. We have tested the Doppler shifting of light in the laboratory but that is not the issue here. Cosmological redshift has a different cause - the expansion of space, and it is that to which you are referring.<br /><br />With cosmological redshift, the light is travelling through space as it expands, which has the effect of "stretching" the light during a long distance journey. By long distance, we are talking about the distances between the galactic clusters, over billions of years.<br /><br />The theory predicts that if an object emits light of a given duration, and then the universe expands to double the size during that lights journey, the light will be received over double that original duration.<br /><br />This is what we see in Type Ia Supernovae. Over a range of redshifts, which also correspond to their apparent magnitude, their duration is as predicted by that time dilation. Both the redshift and the time-dilation are in accord with the expected results in an expanding universe. <div class="Discussion_UserSignature"> <p><font color="#ff0000">_______________________________________________<br /></font><font size="2"><em>SpeedFreek</em></font> </p> </div>

 

[qso1]

I have a book on astronomy which I'll have to dig up to find the table that was interesting to me. The further out one measures, the less reliable. As much as 50% uncertainty for measurement of the most distant objects. And this table was an assembly of the types of measurement techniques and reliability in percentage. A table made by scientists. By there own admission, they are saying that at best, the reliability of distance measurement degrades the further out you go and what technique is utilized (Examples include Cephied variables, type 1a supernovas IIRC).<br /><br />It should also be noted that astronomy is a science in which data is verified the world over by scientists from many nations. Ultimately, only you can decide for yourself as to whether you trust the data but you have asked a good question here because science is also about questioning. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[drwayne]

mindopener9,<br /><br />You have a Private Message waiting. Click on the binking envelope. <img src="/images/icons/smile.gif" /><br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[alkalin]

Cosmological red shift is a convenience to explain red shift in the distant universe, but is an invention that cannot be verified in any way in the lab. Doppler is a valid tool for the investigation of a variety of things such as star rotation speed, and whether nearby objects are moving toward us or in the other direction.<br /><br />When quasars have a very high red shift yet can be found in front of galaxies that are far less red shifted, the interpretation of distance has to be in question based on cosmological red shift. <br /><br />When the most distant galaxies can be found to be very large and have an old age when light left them, the distance and age has to be in question.<br /><br />When physicists predicted the CMB based on black body instead of the BB and were proven correct, there needs to be questioned also the way humans in institutions think. <br />

 

[mindopener9]

Quasars appearing to be in front of galaxies with vastly different redshifts is exactly the sort of discrepancy I was referring to in my own web search on the topic. With these kinds of anomalies present in red shift data, reliability does become an issue and should give pause, to those who would declare "Dark Energy exists, because we have to explain Cosmic Expansion's seeming Acceleration". It is very frustrating that these yardsticks science relies on aren't really standardized at all. I agree, with the distances involved, red shifts are the only way, right now that has agreement with BB theory and, indeed are the very reason BB theory even exists. My question still remains:<br />What if the majority are wrong? Just because it's easier to go along with the pack, does not mean the pack isn't leading you astray, right? <br />The whole question of Dark Energy and the Big Bang theory hangs on the reliability of this Red Shift at great distances to being , at least close, to what is reality. If not,<br />a lot of money and time is being wasted by some very intelligent scientists looking down the wrong alley or even multiple wrong alleys. I've had a lot of doubts for a long time now, about a lot of accepted physics that are all taken as "God's Rock Solid Law" by a lot of folks, who are quite comfortable to go along with the crowd.<br />Perhaps that explains why there are so many fringe science books being advertised all over the place, even in my Astronomy magazine, a publication that I respect, but nevertheless Mainstream.<br />Sure, a lot of these authors just want to make a name for themselves and a quick buck, (Expansion Theory), but a few intrigue me, just because they question the status quo of foundational physics, that so much current research depends upon being stable. I am getting too old (47) to start a career in science and go to university for 4 to 8 years, besides I have a mortgage to pay, so a full-time income is essential. <br />But is modern science fatally <div class="Discussion_UserSignature"> We must progress and expand, or we will stagnate and die. </div>

 

[SpeedFreek]

Yes I know cosmological redshift cannot be verified in a lab, which is why I pointed out that doppler can and <i>has</i> been verified in a lab.<br /><br />The original question only mentioned doppler shift, which has been verified and tested, but the OP was asking about "cosmic expansion" which is theorised to have nothing to do with doppler shift. So I talked about ways that we can test the validity of cosmological redshift and the time-dilation of SNe Ia over a range of redshifts is one such test.<br /><br />We cannot test cosmological redshift in the lab, but we can find different observations that seem to verify it as a valid model. It may not be the correct solution, but we have no other solution as valid as cosmological redshift as caused by the expansion of space.<br /><br />The time-dilation of Type Ia Supernovae over a range of distances would seem to verify the cosmological redshift, unless you can find another mechanism that can account for both of these observed effects.<br /><br />Also, the increase in angular diameter of galaxies above redshift z=1.6 also adds weight to the expansion model, and fits with both the cosmological redshift and the time dilation of the SNe Ia. So you need a different model that can account for <i>all three</i> of these observed effects.<br /><br />The Distance Scale of the Universe shows how it is all supposed to work!<br /><br />Remember that the overwhelming majority of our observations fit this model, but there <i>are</i> exceptions, observations that don't seem to fit, but they are only a very small fraction of the data. So either the model is correct and the anomalies are being misinterpreted somehow, or the anomalies are real and the model needs either an adjustment or to be abandoned for something better.<br /><br />But that "something better" still has to account for the large scale homogeneity, the abundance of light elements, the redshift-magnitude rela <div class="Discussion_UserSignature"> <p><font color="#ff0000">_______________________________________________<br /></font><font size="2"><em>SpeedFreek</em></font> </p> </div>

 

[mindopener9]

Thank you, SpeedFreak for helping to clarify the situation. It IS a very complicated system to fathom, but it seems to fit what we see, in most cases. I sometimes get caught up in the din of fringe physics advertising that grabs one's attention with fantastic claims and "proof" of their own "pet" theories, always different or in conflict with accepted science. I must remember that a lot of testing and people have gone to a lot of meticulous trouble to refine the techniques used to make them as reliable and valid as possible. I'll sleep a little easier, tonight, knowing that at least some of what I have learned so far, astronomically speaking, is still quite worthwhile, and that the consensus is on the right track to discovery..... <div class="Discussion_UserSignature"> We must progress and expand, or we will stagnate and die. </div>

 

[siarad]

There's another redshift measurement, something like 'forest', this is where light travelling through cosmic clouds at different points in space shift all the lines indicating er, something. It was explained to me here a couple of years ago in response to my similar question about expansion which my aging brain has forgotten sorry <img src="/images/icons/frown.gif" />

 

[siarad]

OK found the similar reply by Saiph <b>here</b> <br />Also found <b>this</b> Googling

 

[Saiph]

Ha! I remember that post! Now I don't have to recreate it (I really dislike Uplink's search engine...ugh).<br /><br />So, the hydrogen forest lines are strong evidence that there is cosmological redshift, however there are <i>possible</i> exceptions. Namely the anamolous quasar redshifts pointed out by Halton Arp.<br /><br />Now, these are a small number, compared to the sample size, of exceptions. If he is right, and those quasars aren't redshifted due to the cosmological redshift, especially at such high values (normally suggesting very distant objects) it doesn't mean cosmological redshift is dead. It does mean that it has to be applied more carefully, and one must look for the exceptions.<br /><br />Unless the explaination for the anamolous redshifts can be generalized to answer the entirety of the redshift phenomena.<br /><br />Now, with this in mind, it may seem like a waste of time, money and talent to continue using the standard cosmological redshift paradigm. I am not of that opinion however. The data is gathered, and interpreted, and even if erroneous, it makes any subsequent work easier, and more fruitful with less effort.<br /><br />I.e. any effort there isn't completely wasted, and it does add support and strength to the standard cosmological redshift model if the new studies findings tie into other <i>independent</i> research in a coherent fashion. Note I said strengthen, not prove. <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>

 

[michaelmozina]

<blockquote><font class="small">In reply to:</font><hr /><p>The original question only mentioned doppler shift, which has been verified and tested, but the OP was asking about "cosmic expansion" which is theorised to have nothing to do with doppler shift. So I talked about ways that we can test the validity of cosmological redshift and the time-dilation of SNe Ia over a range of redshifts is one such test. <p><hr /></p></p></blockquote><br /><br />That is not a *controlled* scientific test. <br /><br />It's more like pointing to an *uncontrolled* observation of acceleration and claiming that 'dark energy did it', or 'dark faeries did it'. Slapping a math formula to a metaphysical construct, and then "testing" it on something that is billions of light years away is pretty suspect if your metaphysical construct is suspect to begin with. If I don't accept the concept of "expanding space" (whatever that is), then it really doesn't matter what type of math you attempt to apply to it. <br /><br />Besides, there is growing evidence that the SN1A data has ruled out more theories than it has verified, including ruling out the Lambda theory.<br /><br />http://arxiv.org/abs/astro-ph/0511628<br /> <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[SpeedFreek]

Yes, we know we cannot possibly test for cosmological expansion in the laboratory! It <i>is</i> not and <b>cannot</b> be a controlled scientific test! All we can do is see if we have any other different types of observations that seem to fit the model, and we do.<br /><br />As you say there are scientists who have found observations that don't seem to correlate, and even seem to "rule out all the cosmologies", as that paper says (or more correctly, asks).<br /><br />All we can do is pursue all avenues and look at the bigger picture. We shouldn't abandon mainstream cosmological models because one set of observations <i>might</i> rule out all previous models. Let's wait until we have more evidence against cosmological expansion than we have for it eh?<br /><br />I mean, if we have more evidence that supports it than evidence than conficts with it, should we just throw it out now? There are many scientists pursuing other avenues too. Who knows, one day we might find that someone like Halton Arp was actually right all along, but we should be careful of jumping to false conclusions.<br /><br />It took a long time for science to accept that the Earth was not the centre of the universe, and it took a long time for expansion to be accepted. As the evidence for these theories built up, it finally became futile for <i>(most)</i> people to argue against them. If the weight of new evidence builds up against expansion I am sure it will be indeed be rejected in the end. <div class="Discussion_UserSignature"> <p><font color="#ff0000">_______________________________________________<br /></font><font size="2"><em>SpeedFreek</em></font> </p> </div>