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Author Topic:   What Properties Might Light of Millennia Past Have that Today's Doesn't?
Percy
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Posts: 22691
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.8


(1)
Message 3 of 170 (601850)
01-24-2011 5:42 PM
Reply to: Message 1 by Noitartst
01-24-2011 4:53 PM


Noitartst writes:
Most of all, what comes to mind for me is the speed of light. Its speed has been observed to be slowing consistently since first observed in the 19th century...
I'd be very interested in hearing about these observations of the consistently slowing speed of light.
--Percy

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 Message 1 by Noitartst, posted 01-24-2011 4:53 PM Noitartst has not replied

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Percy
Member
Posts: 22691
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.8


(1)
Message 23 of 170 (674328)
09-27-2012 8:48 PM
Reply to: Message 21 by LimpSpider
09-27-2012 7:50 PM


LimpSpider writes:
It was the same value yesterday, and the day before, so it's not extrapolation to say that tomorrow should be the same.
So if it was 5 the day before yesterday and 6 yesterday and 7 today, extrapolation says it will be 8 tomorrow.
But if it was 5 the day before yesterday and 5 yesterday and 5 today, extrapolation says it will be 5 tomorrow.
Extrapolation in this context just means the use of simple math to project forward in time. This is just basic terminology. You might want to question whether you have the necessary background to be discussing this.
--Percy

This message is a reply to:
 Message 21 by LimpSpider, posted 09-27-2012 7:50 PM LimpSpider has replied

Replies to this message:
 Message 24 by LimpSpider, posted 09-27-2012 8:52 PM Percy has replied

  
Percy
Member
Posts: 22691
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.8


(2)
Message 25 of 170 (674338)
09-27-2012 9:13 PM
Reply to: Message 24 by LimpSpider
09-27-2012 8:52 PM


LimpSpider writes:
Percy, are you talking about time?
Are you kidding? This is what you said:
LimpSpider in Message 21 writes:
It was the same value yesterday, and the day before, so it's not extrapolation to say that tomorrow should be the same.
It wasn't me that started talking about time, it was you. Just what did you think you were referring to when you talked about yesterday and the day before and tomorrow if not time?
We appear to be using different definitions of extrapolation.
No. *I* appear to be using the definition of extrapolation. You appear to have no clue.
In this context that you have just mentioned, I have no objection.
In this context? Are you daft? It's your context. You said yesterday and the day before and tomorrow, and so did I. I did not change context on you. Is English your first language?
--Percy

This message is a reply to:
 Message 24 by LimpSpider, posted 09-27-2012 8:52 PM LimpSpider has not replied

  
Percy
Member
Posts: 22691
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.8


Message 28 of 170 (674468)
09-29-2012 9:09 AM
Reply to: Message 27 by LimpSpider
09-29-2012 7:08 AM


LimpSpider writes:
But from something we can observe, yeah? Have you seen the cosmological statement?
Here's a link to what you're referring to: Cosmology Statement
But I think you'd be drifting way off topic if you got into that. It doesn't even mention light. Why don't you propose a new topic over at Proposed New Topics if that's what you want to talk about.
--Percy

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 Message 27 by LimpSpider, posted 09-29-2012 7:08 AM LimpSpider has replied

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 Message 30 by LimpSpider, posted 09-29-2012 9:18 AM Percy has replied

  
Percy
Member
Posts: 22691
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.8


Message 32 of 170 (674474)
09-29-2012 9:29 AM
Reply to: Message 30 by LimpSpider
09-29-2012 9:18 AM


LimpSpider writes:
No, I don't really want to talk about that, not now.
Okay.
By the way, in response to your avatar I thought I'd mention that I am following my dream of an eventual reconciliation between science and religion as each side learns more about the other.
--Percy

This message is a reply to:
 Message 30 by LimpSpider, posted 09-29-2012 9:18 AM LimpSpider has replied

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Percy
Member
Posts: 22691
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.8


(1)
Message 50 of 170 (674546)
09-30-2012 9:28 AM
Reply to: Message 42 by LimpSpider
09-29-2012 9:07 PM


Hi LimpSpider,
This thread is about how light today might be different from light in the past, as a reading of Message 1 from Noitartst makes clear. For some reason he never participated in his own thread so we can not put too much of a finer point on what he wanted to discuss, but it is clear that he was talking about tired light because he said, "Most of all, what comes to mind for me is the speed of light. Its speed has been observed to be slowing consistently since first observed in the 19th century..."
Creationists are attracted to the tired light idea because it means that the universe is not necessarily as old as it seems. For example, light reaching Earth from a star 13 billion light years distant is assumed to have taken 13 billion light years to reach us because light travels one light year per year. But the time could have been much less if light in the past traveled a great deal faster than it does today.
People have been trying to get a handle on what you're trying to say, but now after 17 posts we're still not sure. Are you trying to say something about tired light? If so, what is it? If not, you should perhaps propose a new thread over at Proposed New Topics.
--Percy

This message is a reply to:
 Message 42 by LimpSpider, posted 09-29-2012 9:07 PM LimpSpider has replied

Replies to this message:
 Message 51 by JonF, posted 09-30-2012 9:51 AM Percy has replied
 Message 55 by LimpSpider, posted 09-30-2012 6:46 PM Percy has replied

  
Percy
Member
Posts: 22691
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.8


Message 53 of 170 (674553)
09-30-2012 12:48 PM
Reply to: Message 51 by JonF
09-30-2012 9:51 AM


Good point, I'll stop referring to decreasing c over time as tired light.
--Percy

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 Message 51 by JonF, posted 09-30-2012 9:51 AM JonF has not replied

  
Percy
Member
Posts: 22691
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.8


(1)
Message 58 of 170 (674598)
09-30-2012 7:15 PM
Reply to: Message 55 by LimpSpider
09-30-2012 6:46 PM


Hi LimpSpider,
Ignore my reference to tired light. I should have said decreasing c.
LimpSpider writes:
JonF, isn’t the energy directly related to the speed? As in E=mc^2?
That equation is the equivalency between mass and energy. It isn't the way to calculate the amount of energy in a quantum of light, which would be a function of wavelength. Here's the right equation:
E = hc / λ
E = energy
h = Planck's constant
c = speed of light
λ = wavelength
Therefore, if light from those clusters that are receding are losing energy (if they lose energy I think they would lose luminosity), we would not see it.
Luminosity or intensity is a measure of the number of photons arriving from a light source, and the number of photons arriving would not change. What changes in an expanding universe is the wavelength of light, and so the energy of a photon does decrease as it travels through an expanding universe.
In other words, we would still see light arriving from distant galaxies, but shifted toward the red end of the spectrum. The amount of red shift is a measure of how much universe the light has passed through, which tells us the distance of the object.
--Percy

This message is a reply to:
 Message 55 by LimpSpider, posted 09-30-2012 6:46 PM LimpSpider has replied

Replies to this message:
 Message 60 by LimpSpider, posted 09-30-2012 9:26 PM Percy has replied

  
Percy
Member
Posts: 22691
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.8


(1)
Message 61 of 170 (674602)
09-30-2012 9:52 PM
Reply to: Message 60 by LimpSpider
09-30-2012 9:26 PM


LimpSpider writes:
Ok, if light was faster in the past and slowed down, (it has to have been, it could not have been slower) would not the light disappear from view as the c was reduced? Would not it, in such a case, show blueshifts?
It's your theory, I have no idea what would happen as c lessened. Here's the equation again:
E = hc / λ
Is it part of your theory that as c decreased energy would have remained constant? If so then reducing c would have reduced wavelength, which *would* be a blueshift.
But c is a constant because it is a function of the fine structure constant, and significant changes in that constant would have widespread effects on the nature of our universe, effects that we have not observed. One of the effects would be that carbon based life forms could not exist, mainly because carbon could not be produced by stars, but since we're here the fine structure constant must have been pretty much the same when life first began as it is today.
If the speed of light was much greater in the past, either the frequencies were higher due to higher excitation energies of the sources or the received wavelengths are shortened by the Doppler effect.
Frequency is the inverse of wavelength. You've just used two ways of referring to the same thing to reach two different conclusions, and if you're keeping energy constant then you've got it backwards because increasing c means frequencies must be lower and wavelengths longer.
But whatever the actual details of your ideas, they're just pointless speculation because there's no evidence for any of them.
--Percy

This message is a reply to:
 Message 60 by LimpSpider, posted 09-30-2012 9:26 PM LimpSpider has replied

Replies to this message:
 Message 62 by LimpSpider, posted 09-30-2012 9:58 PM Percy has seen this message but not replied
 Message 63 by NoNukes, posted 09-30-2012 10:10 PM Percy has replied
 Message 80 by foreveryoung, posted 10-02-2012 1:27 AM Percy has seen this message but not replied

  
Percy
Member
Posts: 22691
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.8


Message 64 of 170 (674605)
09-30-2012 10:33 PM
Reply to: Message 63 by NoNukes
09-30-2012 10:10 PM


NoNukes writes:
I think this is begging the question. Frequency and wavelength are inversely related given that the propagation velocity is constant.
But if he's holding energy constant (which he didn't specify but I was trying to respond to his questions and so needed to assume something constant) then frequency and wavelength are still kind of locked together. If energy is not held constant then I think you're right.
AbE: After thinking about this a bit more I realized that holding the energy constant would also hold the frequency constant, so varying c while keeping energy constant would vary the wavelength.
--Percy
Edited by Percy, : AbE.

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 Message 67 by LimpSpider, posted 10-01-2012 1:15 AM Percy has replied

  
Percy
Member
Posts: 22691
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.8


Message 69 of 170 (674629)
10-01-2012 9:38 AM
Reply to: Message 67 by LimpSpider
10-01-2012 1:15 AM


LimpSpider writes:
Um, Percy, I gave you more information on the subject. Did you read it?
Are you referring to your Message 62? The one with the bare link? Have your read the Forum Guidelines:
  1. Bare links with no supporting discussion should be avoided. Make the argument in your own words and use links as supporting references.
Anyway, so what did you say in Message 62:
LimpSpider in Message 62 writes:
Technically, it's all just speculation. VSL has not been observed. Has it? (More details: A new cosmology: solution to the starlight travel time problem - creation.com)
You concede it's all just speculation and state that VSL (Variable Speed of Light) has not been observed. What is there to respond to?
Or were you maybe referring to the one sentence I didn't quote from the longest paragraph in your Message 60, the only one that continued your line of argument:
In either case, referenced against standard sources on Earth, such light would appear blueshifted.
Given that everything you were saying was speculation in the absence of information, why do you feel it was necessary to respond to this part of the speculation?
My Message 61 attempts to discuss the implications of yours ideas while pointing out that you're fairly non-specific, like not specifying whether you're keeping energy constant. I also pointed out the problems introduced by significant changes in c, which would require significant changes in the fine structure constant, making life in our universe impossible. Maybe you'd like to address that.
You have a tendency toward brevity. Next time you would like a response from anyone about something, specify which part of which message so people don't have to scramble around answering multiple messages because they don't know which the heck part of which message you're talking about.
--Percy

This message is a reply to:
 Message 67 by LimpSpider, posted 10-01-2012 1:15 AM LimpSpider has replied

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Percy
Member
Posts: 22691
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.8


Message 87 of 170 (674752)
10-02-2012 3:45 PM
Reply to: Message 86 by foreveryoung
10-02-2012 3:34 PM


foreveryoung writes:
I don't care how many times it has been repeated; it is merely your assertion and nothing more. All of the constants are derived from a deeper reality and they don't change alone but in tandem. This tandem change keeps all the ramifications that you insist would happen from happening.
You think you can change the fundamental constants in ways that would change just one aspect of our universe, such as c, without changing anything else. It would be best if Son Goku or Cavediver would comment, but I think what people are trying to tell you is that that can't happen. If that's correct then I see no reason why you should just accept this answer without understanding why it is true. But acquiring that understanding might represent a considerable investment in time, and unless you do that you have no excuse for rejecting the answer.
... so I will blow up and get banned.
Don't get so angry that you forget about Report Discussion Problems Here 3.0.
--Percy

This message is a reply to:
 Message 86 by foreveryoung, posted 10-02-2012 3:34 PM foreveryoung has not replied

  
Percy
Member
Posts: 22691
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.8


(1)
(1)
Message 95 of 170 (674804)
10-03-2012 8:42 AM
Reply to: Message 91 by foreveryoung
10-03-2012 12:25 AM


foreveryoung writes:
The fact of the matter is that such changes in the constants have indeed produced visible effects on our universe. Those changes are 1.an enormous amount of radioactive decay in a very short time.
There is no evidence that accelerated radioactive decay has ever occurred during the history of the Earth, and the light from stars emitted during the supposed flood tells us that there was no accelerated radioactive decay at that time, those stars obviously obeying the same laws of physics we observe here.
2. Starlight that has reached us from a distance that in an amount of time that would be impossible to replicate today.
Do you mean that we're unable to replicate the passage of light through billions of light years of space as part of an experiment? If so then I guess you're correct, but you're going to have to explain why you think that's relevant.
3. Accelerated plate tectonics that occurred in much shorter time than would be possible with today's rates.
There is no evidence of accelerated plated tectonics.
Arguing for events for which you can offer no evidence, which indeed seem to be ruled out by the evidence, isn't very persuasive.
--Percy
Edited by Percy, : Grammar.

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 Message 91 by foreveryoung, posted 10-03-2012 12:25 AM foreveryoung has replied

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 Message 97 by foreveryoung, posted 10-03-2012 11:34 PM Percy has seen this message but not replied
 Message 99 by foreveryoung, posted 10-03-2012 11:38 PM Percy has replied

  
Percy
Member
Posts: 22691
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.8


(2)
(1)
Message 106 of 170 (674923)
10-04-2012 9:14 AM
Reply to: Message 99 by foreveryoung
10-03-2012 11:38 PM


foreveryoung writes:
percy writes:
There is no evidence that accelerated radioactive decay has ever occurred during the history of the Earth,
Yes there is. The earth is orders of magnitude younger than 4.56 billions years old, therefore there has been accelerated radioactive decay.
The topic isn't the age of the Earth, but you've made it part of your argument in favor of changing physical constants, so we're going to have to discuss it a bit.
Your chain of argument is that we know that physical constants had different values in the past because of accelerated radioactive decay, and we know that accelerated radioactive decay must have happened because the Earth is young.
So, remembering that the actual topic is the properties of light, do you have any evidence for a young Earth that would support your claim of accelerated radioactive decay that would in turn support your claim of changing physical constants?
--Percy

This message is a reply to:
 Message 99 by foreveryoung, posted 10-03-2012 11:38 PM foreveryoung has not replied

  
Percy
Member
Posts: 22691
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.8


Message 125 of 170 (675178)
10-07-2012 2:10 PM
Reply to: Message 123 by zaius137
10-07-2012 1:34 PM


Re: The constants do change.
Hi Zaius,
I'm having a hard time following you. The conversation has gone like this:
ZaiusIt depends on which constants are affected and to what degree. That would be the difference between the decay of uranium for instance verses that of say heavy water.
NoNukesHeavy water is not radioactive. Deuterium is stable as is Oxygen 16. What comparison are you trying to make between water and uranium? After all, it would be extremely difficult for hydrogen to emit an alpha particle.
ZaiusI guess to say that Tritium releases beta particles and can combine to form a heavy water means little to you. The point was contrasting beta decay with some of the decays unstable Uranium isotopes produce.
You appear to be claiming that your comparison of the decay of uranium (which does decay) versus the decay of heavy water (which doesn't decay) was actually an argument about the formation of heavy water through the decay of tritium. What does one have to do with the other, and why do you think the beta decay of tritium into helium has anything to do with the formation of heavy water? And how does all this tie into changing constants?
--Percy

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 Message 123 by zaius137, posted 10-07-2012 1:34 PM zaius137 has not replied

Replies to this message:
 Message 126 by NoNukes, posted 10-07-2012 2:28 PM Percy has replied

  
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