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Author Topic:   Tired Light
Buzsaw
Inactive Member


Message 256 of 309 (193779)
03-23-2005 8:03 PM
Reply to: Message 249 by Sylas
03-23-2005 5:23 PM


Re: Clarification on forum conventions for long threads
Sylas is right, Lyndon. That 300 limit policy has been in effect for some time now. On some topics a new thread has been opened such as (Tired Light II) if the key participants agree that there's enough more significant stuff to cover on the topic. That's how I understand the policy. Admins can clarify, if needed. At any rate, though the math has been over my head, having you here has benefited us all, so as for all to see the pros and cons of this and to watch this most interesting match of the scientific minds from different perspectives from the benches.
I'm getting the impression as I read it all that you are introducing some logic into the foray so as to "bring cosmology down to earth" --logic, the stuff modern physics so despises, especially BBers, who've got to rely on this notion of expanding space or they're dead.
At any rate, I DO HOPE that you will stay logged in and bless us all with some more interesting science from a different perspective, be it on tired light or other stuff when you can fit it into your busy schedule. I would be interested in some comment from your perspective in the ongoing thread of the "fabric of space."
This thread has some more space yet. Get your share of it.

The immeasurable present is forever consuming the eternal future and extending the infinite past. buzsaw

This message is a reply to:
 Message 249 by Sylas, posted 03-23-2005 5:23 PM Sylas has not replied

Replies to this message:
 Message 259 by Eta_Carinae, posted 03-23-2005 9:15 PM Buzsaw has replied
 Message 261 by Funkaloyd, posted 03-23-2005 10:00 PM Buzsaw has replied

RAZD
Member (Idle past 1395 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 257 of 309 (193781)
03-23-2005 8:14 PM
Reply to: Message 249 by Sylas
03-23-2005 5:23 PM


Re: Clarification on forum conventions for long threads
to be fair, it is possible to start a new post based on the original OP if it is still a valid OP and there is interest in pursuing it.
This happened with {Age Correlations} and one on the exodus I believe (buz would know).
other than that, the maximum I have seen is just over 300 on any topic, regardless of interest, activity and honesty in debate.
{added by edit ... heh, high buz: ya beat me to it}
This message has been edited by RAZD, 03*23*2005 08:16 PM
{The The 300 message limit for topics topic. - Adminnemooseus}
This message has been edited by Adminnemooseus, 03-23-2005 08:36 PM

This message is a reply to:
 Message 249 by Sylas, posted 03-23-2005 5:23 PM Sylas has not replied

RAZD
Member (Idle past 1395 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 258 of 309 (193787)
03-23-2005 8:38 PM
Reply to: Message 247 by Sylas
03-23-2005 4:16 PM


Re: Do electrons in a thin plasma act in unison? Yes they do!
OT comment:
nice paper on pioneer anomalies. section XI was most informative: looks like things are hopping. could indeed be a fun new topic, but it needs a foil to keep the discussion going eh?

This message is a reply to:
 Message 247 by Sylas, posted 03-23-2005 4:16 PM Sylas has not replied

Eta_Carinae
Member (Idle past 4365 days)
Posts: 547
From: US
Joined: 11-15-2003


Message 259 of 309 (193792)
03-23-2005 9:15 PM
Reply to: Message 256 by Buzsaw
03-23-2005 8:03 PM


This is an example of why cranks are dangerous..
buzsaw writes:
Sylas is right, Lyndon. That 300 limit policy has been in effect for some time now. On some topics a new thread has been opened such as (Tired Light II) if the key participants agree that there's enough more significant stuff to cover on the topic. That's how I understand the policy. Admins can clarify, if needed. At any rate, though the math has been over my head, having you here has benefited us all, so as for all to see the pros and cons of this and to watch this most interesting match of the scientific minds from different perspectives from the benches.
I'm getting the impression as I read it all that you are introducing some logic into the foray so as to "bring cosmology down to earth" --logic, the stuff modern physics so despises, especially BBers, who've got to rely on this notion of expanding space or they're dead.
At any rate, I DO HOPE that you will stay logged in and bless us all with some more interesting science from a different perspective, be it on tired light or other stuff when you can fit it into your busy schedule. I would be interested in some comment from your perspective in the ongoing thread of the "fabric of space."
This thread has some more space yet. Get your share of it.
Some people, of course with no skill set to discern otherwise, believe that the cranks in society might be on to something.
buz, how is he introducing logic when by his analogy a computer monitor would be powered by electrons a metre apart in a vacuum. Ya think that would work??

This message is a reply to:
 Message 256 by Buzsaw, posted 03-23-2005 8:03 PM Buzsaw has replied

Replies to this message:
 Message 262 by Buzsaw, posted 03-24-2005 12:36 AM Eta_Carinae has replied

Sylas
Member (Idle past 5250 days)
Posts: 766
From: Newcastle, Australia
Joined: 11-17-2002


Message 260 of 309 (193802)
03-23-2005 9:42 PM
Reply to: Message 255 by gnojek
03-23-2005 7:33 PM


Re: Malmquist Bias
gnojek writes:
lyndonashmore writes:
The paper is famous on forums because they are looking at supernovae Ia and ‘select’ or get rid of quite a large sample of supernovae. Why not include them all?
because Type 1A supernova are a result of a very specific phenomenon which occurs with a specific energy, thus giving observers sort of a standard candle. They all have the same light output and so you can calculate distance using the luminosity of the supernova
This is not really an answer to Lyndon's question. The paper in question is Timescale Stretch Parameterization of Type Ia Supernova B-band, at astro-ph/0104382, by various authors including Permutter. The selection was not simply based on picking Ia supernovae, though that was part of it of course.
What Lyndon is referring to is that the paper uses 42 supernova; and yet the Supernova Cosmology Project has identified over 75 high redshift type Ia supernovae. Furthermore, they actually focus on only 35 of those 42.
The reasons for the 7 exclusions are explained on page 4 of the paper, and the reason for the selection of 42 is that those are the ones for which a light curve analysis was available. The dataset is taken from that used in an early paper, Measurements Of Ω and Λ From 42 High-Redshift Supernovae, by Perlmutter et al, astro-ph/9812133 (1998). There is a fairly detailed discussion of the dataset in that paper (section 4), though I’d like to see a simpler and more concise statement somewhere. I will ask. They were limited to supernova actually found before reaching peak luminosity so as to obtain a good light curve; supernova which could be reliably assigned to type Ia, and supernova which were not distorted by reddening effects. (Reddening is not redshift; but a result of frequency dependent obscuring by dust clouds.)
Hubble saw all this redshift all over the place.
He very roughly showed that the redshift was proportional to distance.
(Distance that was measured by other means.)
He looked everywhere and saw just about every galaxy was redshifted.
He proposed that this might be due to the Doppler effect.
Last sentence there is not quite right. Hubble had very little to say about causes; he primarily noted the redshift distance relation. For various reasons (a problem with his standard candles) he got a far higher Hubble constant than was correct, and his value was inconsistent with Doppler shifts, as it would have had all galaxies starting out from a common start point only a couple of billion years ago. Hubble preferred the tired light idea, if anything.
Rest of the post I basically agree with. Don’t be put off by these comments! All contributions welcome. There is plenty of scope here for new threads. There is nothing wrong with starting new threads to consider specifically focussed topics arising from this thread.
Cheers -- Sylas
This message has been edited by Sylas, 03-23-2005 09:44 PM

This message is a reply to:
 Message 255 by gnojek, posted 03-23-2005 7:33 PM gnojek has replied

Replies to this message:
 Message 265 by gnojek, posted 03-24-2005 4:42 PM Sylas has not replied

Funkaloyd
Inactive Member


Message 261 of 309 (193811)
03-23-2005 10:00 PM
Reply to: Message 256 by Buzsaw
03-23-2005 8:03 PM


Re: Clarification on forum conventions for long threads
quote:
I'm getting the impression as I read it all that you are introducing some logic into the foray so as to "bring cosmology down to earth" --logic, the stuff modern physics so despises, especially BBers, who've got to rely on this notion of expanding space or they're dead.
It would be interesting to know whether Ashmore believes the supposedly crazy and illogical idea that space is made of nothing and yet is non-Euclidean (curved).

This message is a reply to:
 Message 256 by Buzsaw, posted 03-23-2005 8:03 PM Buzsaw has replied

Replies to this message:
 Message 263 by Buzsaw, posted 03-24-2005 12:47 AM Funkaloyd has not replied

Buzsaw
Inactive Member


Message 262 of 309 (193854)
03-24-2005 12:36 AM
Reply to: Message 259 by Eta_Carinae
03-23-2005 9:15 PM


Re: This is an example of why cranks are dangerous..
Some people, of course with no skill set to discern otherwise, believe that the cranks in society might be on to something.
buz, how is he introducing logic when by his analogy a computer monitor would be powered by electrons a metre apart in a vacuum. Ya think that would work??
I don't think so, Eta, but then I didn't understand the physics of the exchange of debate on that post which three of you responded to enough to make a judgement as to whether it was completely refuted. I doubt it made any less sense than the balloon expansion model you people use for expanding space though, with everything expanding but the space between the photons and electrons of atoms of the matter the dots on the balloon represent. You needn't explain that though, as I do understand Sylas's and Percy's arguments about that. it's just not logical enough for me to accept and of course, off topic here.
Having said that, I must say that I am highly impressed with the intelligence and acquired knowledge of you, Sylas, Percy, Razd and others as well as Lyndon having read it as it progressed along. You've all got to be commended for the keen minds and hard work needed to do a thread like this. For this reason, I cringe when any of you, including Lyndon imply that another is stupid, et al.
For me, the logic of tired light makes more sense than an expanding space, given the property of space which is logically as well as difinitively a vacuum, imo, incapable of expansion. Logically it would seem that if there's all these jillions of particles between us and the ultra-distant redshifted galaxy they've gotta do something to that light by the time it runs that gauntlet of billions of lightyears through them. No, I can't begin to do the physics math, et al and I'm not totally convinced about tired light, but logically, it appears to be the best yet. It wouldn't surprise me if you're all wrong on the physics and somebody will come up with something better.

The immeasurable present is forever consuming the eternal future and extending the infinite past. buzsaw

This message is a reply to:
 Message 259 by Eta_Carinae, posted 03-23-2005 9:15 PM Eta_Carinae has replied

Replies to this message:
 Message 264 by Eta_Carinae, posted 03-24-2005 1:44 AM Buzsaw has not replied

Buzsaw
Inactive Member


Message 263 of 309 (193858)
03-24-2005 12:47 AM
Reply to: Message 261 by Funkaloyd
03-23-2005 10:00 PM


Re: Clarification on forum conventions for long threads
It would be interesting to know whether Ashmore believes the supposedly crazy and illogical idea that space is made of nothing and yet is non-Euclidean (curved).
From what I gather, if space is nothing but geometry, given the definition of geometry, you've all got a Euclidean space, whether you want to admit it or not. You're all trying to make space do something a vacuum can't do. That's my 2cts worth of logic that, imo, will buy what it would take a hundred dollars worth of geometric math to buy.
{ AdminSylas notes: gentle reminder to all contributors; me, Eta, buz, Funkaloyd, Lyndon. This thread is for tired light; not geometry of space. Buz has answered the question; let's not debate it further in this thread. No responses to this message, please. Thanks. }
This message has been edited by AdminSylas, 03-24-2005 12:56 AM

The immeasurable present is forever consuming the eternal future and extending the infinite past. buzsaw

This message is a reply to:
 Message 261 by Funkaloyd, posted 03-23-2005 10:00 PM Funkaloyd has not replied

Eta_Carinae
Member (Idle past 4365 days)
Posts: 547
From: US
Joined: 11-15-2003


Message 264 of 309 (193886)
03-24-2005 1:44 AM
Reply to: Message 262 by Buzsaw
03-24-2005 12:36 AM


Re: This is an example of why cranks are dangerous..
buz,
tired light is a failure for about 10 times the material of this entire thread. Not just what has been mentioned here.
For one thing, every thing beyond a nearby distance would be blurry. All this absorig and reradiating of photons would not preserve the original direction of the photons. It would have to introduce a "blurriness" to everything distant.
You can take my word for it, or not, but tired light is considered one of the weakest challenges to BB Theory.

This message is a reply to:
 Message 262 by Buzsaw, posted 03-24-2005 12:36 AM Buzsaw has not replied

gnojek
Inactive Member


Message 265 of 309 (194129)
03-24-2005 4:42 PM
Reply to: Message 260 by Sylas
03-23-2005 9:42 PM


Re: Malmquist Bias
Ah! Thanks for the explanation. Yeah, I couldn't believe he was that dense. I guess I need to do more than skim and read through these things so quickly. Yeah, hmm, I wonder why they were so selective with their supernovae. I'll just read the paper (oh, and you explained it as well).
And, I understand what redshift is, but I guess you can't assume anything here.
Ah, I didn't realize that it wasn't Hubble that proposed the Doppler origins of redshift.
I also wanted to put a little smiley or something at the end.
I realize reading my post that the exclamation point makes me look angry or something. Eh, I'll figure it out. Oh, you have type the smiley name.
This message has been edited by gnojek, 03-24-2005 04:45 PM

This message is a reply to:
 Message 260 by Sylas, posted 03-23-2005 9:42 PM Sylas has not replied

Admin
Director
Posts: 12993
From: EvC Forum
Joined: 06-14-2002
Member Rating: 2.1


Message 266 of 309 (198146)
04-10-2005 8:53 PM


Any Final Assessments
I noticed this recently active thread while poking around today and recalled it as a very interesting and very techical discussion. I'm curious what members and lurkers think. Was anyone convinced one way or the other? Did anyone win the "debate"?

--Percy
EvC Forum Director

Replies to this message:
 Message 267 by peaceharris, posted 04-11-2005 6:08 AM Admin has not replied

peaceharris
Member (Idle past 5586 days)
Posts: 128
Joined: 03-28-2005


Message 267 of 309 (198233)
04-11-2005 6:08 AM
Reply to: Message 266 by Admin
04-10-2005 8:53 PM


Re: Any Final Assessments
Percy writes:
Was anyone convinced one way or the other?
I neither believe in 'tired light' nor 'space expansion'. Infact I don't even believe that redshifted spectra with z>1 exists. I would truly appreciate if someone could show me a spectrum where Hydrogen lines have been redshifted by z>1.
Director,
Are you the person who created this website? My hearty congratulations. There is someone else who posts using the name Percy. Are you both the same person? What must someone do to get promoted from junior member to normal member? What must a normal member do to get promoted to an administrator?

This message is a reply to:
 Message 266 by Admin, posted 04-10-2005 8:53 PM Admin has not replied

Replies to this message:
 Message 268 by Adminnemooseus, posted 04-11-2005 6:57 AM peaceharris has not replied
 Message 269 by Eta_Carinae, posted 04-11-2005 6:58 AM peaceharris has replied

Adminnemooseus
Administrator
Posts: 3974
Joined: 09-26-2002


Message 268 of 309 (198236)
04-11-2005 6:57 AM
Reply to: Message 267 by peaceharris
04-11-2005 6:08 AM


Re: Forum operation questions
Peaceharris - I've responded to your off-topic questions here.
Adminnemooseus

This message is a reply to:
 Message 267 by peaceharris, posted 04-11-2005 6:08 AM peaceharris has not replied

Eta_Carinae
Member (Idle past 4365 days)
Posts: 547
From: US
Joined: 11-15-2003


Message 269 of 309 (198237)
04-11-2005 6:58 AM
Reply to: Message 267 by peaceharris
04-11-2005 6:08 AM


peace
how are you able to make any judgments on the scientific material when your supernovae questions show that you don't have a science background or knowledge in these areas?
Spectrum at z=3 of a Lyman Break galaxy with strong [OIII] emission
Error 404: File Not Found | University of Alabama College of Arts & Sciences
Here are a whole bunch of high z quasars
http://www.journals.uchicago.edu/...3/200511/200511.fg2.html
DO YOU see that big peak on the left of all the quasar spectra?
That is the Lyman Alpha emission line. Divide it's wavelength by (1+z) and you'll see you get 1216 Angstroms.
Notice how the largeest peak also has a peak almost on top of it at slightly higher wavelength? That is N V emission at a rest wavelength of 1240A.
The next biggest peak is CIV emission at a rest wavelength of 1549 A.
The large peak on the far right is CIII emission at a rest wavelength of 1909 A.
How many more do you need????
How can you straightfaced make the claim such spectra do not exist?
In fact I'll make the claim you don't know enough science to know one way or the other.
You seem to be the classic example of someone who has a conclusion already etched in the mind and you then go out, with little knowledge I might add, and try to squeeze the evidence to fit your conclusion.
I saw how you did this with your radioactive dating "paper". Now you are doing it to astrophysics.
This message has been edited by Eta_Carinae, 04-11-2005 05:59 AM
This message has been edited by Eta_Carinae, 04-11-2005 05:59 AM

This message is a reply to:
 Message 267 by peaceharris, posted 04-11-2005 6:08 AM peaceharris has replied

Replies to this message:
 Message 270 by peaceharris, posted 04-11-2005 11:03 AM Eta_Carinae has replied

peaceharris
Member (Idle past 5586 days)
Posts: 128
Joined: 03-28-2005


Message 270 of 309 (198265)
04-11-2005 11:03 AM
Reply to: Message 269 by Eta_Carinae
04-11-2005 6:58 AM


Re: peace
In message 267, I wrote:
I would truly appreciate if someone could show me a spectrum where Hydrogen lines have been redshifted by z>1.
Notice that I used the plural 'lines'
It is easy to make a claim for a single Hydrogen line.
This Lyman alpha line isn't backed up other redshifted Hydrogen lines.
Objects which have hydrogen usually emit many hydrogen lines.
eta writes:
DO YOU see that big peak on the left of all the quasar spectra?
That is the Lyman Alpha emission line. Divide it's wavelength by (1+z) and you'll see you get 1216 Angstroms.
Notice how the largeest peak also has a peak almost on top of it at slightly higher wavelength? That is N V emission at a rest wavelength of 1240A.
The next biggest peak is CIV emission at a rest wavelength of 1549 A.
The large peak on the far right is CIII emission at a rest wavelength of 1909 A.
I wasn't asking for N and C lines. I was being kind to you by requesting H lines, since Hydrogen is the most abundant element in the universe.
eta writes:
How many more do you need????
I want 1 sample spectrum where I can see the Balmer or Lyman series redshifted with z>1.
Anyone can make the claim that an emission line seen at 5700A is actually a redshifted 1216A line. It is also easy to claim that the 5700A line is a slightly blue-shifted Na-I line.
But if you cannot back it up with other H lines, you need to explain why objects near us (such as the sun) show many H lines, but objects far away show only a single H line.
Please try again.

This message is a reply to:
 Message 269 by Eta_Carinae, posted 04-11-2005 6:58 AM Eta_Carinae has replied

Replies to this message:
 Message 271 by Percy, posted 04-11-2005 12:13 PM peaceharris has replied
 Message 273 by Eta_Carinae, posted 04-11-2005 1:25 PM peaceharris has not replied

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