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Author Topic:   Falsifying a young Universe. (re: Supernova 1987A)
Percy
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Posts: 22359
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.7


Message 60 of 948 (176285)
01-12-2005 3:14 PM
Reply to: Message 59 by simple
01-12-2005 2:55 PM


Re: a simple question
cosmo writes:
quote:
I don't think that anyone has mentioned the major fact recently ... the measurement of the distance to SN1987A does not involve the speed of light
Well, if we use 'light years' to measure the distance, I guess it is involved. Important, because the very same unit measurement is always tranformed into time measurements, which are then so often held up as overruling actual creation time - as in this very thread, where the whole thing is to try to say exactly that!
A light year is a measure of distance. It assumes the speed of light is 299,792,458 m/s, and it is the distance light travels at this speed in a year. Even if it turns out that the speed of light was different in the past, the length of the light year would not change because it is based on the speed of light as measured in modern times.
You are correct, though, that the equality of light years with the time that has passed since the light left a distant object like a star would no longer hold if light has not always traveled at the speed measured today.
There is no evidence that light has ever traveled at a speed different from that measured today.
--Percy

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 Message 59 by simple, posted 01-12-2005 2:55 PM simple has replied

Replies to this message:
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Percy
Member
Posts: 22359
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.7


Message 67 of 948 (176366)
01-12-2005 8:33 PM
Reply to: Message 66 by JonF
01-12-2005 7:55 PM


Re: a simple question
JonF writes:
The speed of light in a vacuum is constant. Light has been slowed to ridiculously slow speeds in physical media, which says nothing about the speed of light in a vacuum.
The apparent reduction in the speed of light in physical media such as glass and water is because the light is absorbed and retransmitted. This process takes place at different rates for different frequencies (and therefore different energies) of light, which also explains why different frequencies of light appear to have different speeds within the media. When traveling from its transmission by one atom to its reception by another, light always travels at the speed of light. Another way to think about the speed of light is that its the speed at which the effects of physical phenomena are transmitted throughout space.
One thought experiment makes this last fact especially apparent. Imagine you wanted instantaneous communications with the moon, instead of having to wait 1.3 seconds for radio communications. You construct a rigid steel rod from the earth to the moon. When you push your end of the rod on earth, the other end of the rod on the moon moves instaneously. Voila! Instant communication! Except that it's not. It takes the fact that the end of the rod on earth has been pushed 1.3 seconds to reach the moon. And probably longer, because our rigid rod isn't actually perfectly rigid.
--Percy

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Percy
Member
Posts: 22359
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.7


Message 85 of 948 (176487)
01-13-2005 8:38 AM
Reply to: Message 83 by simple
01-13-2005 2:25 AM


Re: into the mystic
cosmo writes:
You see, so far all this thread has offered, I think, as evidence, would be an explosion a great distance away, in which it is thought, that decay rates of certain things were the same as now. Big deal.
You were also offered much other evidence, for example, of the speed of light being measured to be the same at great distances from us, for example, Message 56 by Loudmouth.
It is difficult to think of a helpful response to "Big deal." Can you put into words why you think inconclusive the evidence showing that the speed of light, decay rates, and other physical constants, are the same everywhere and in every era that we look in the universe?
--Percy

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 Message 83 by simple, posted 01-13-2005 2:25 AM simple has replied

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 Message 95 by simple, posted 01-13-2005 4:05 PM Percy has replied

  
Percy
Member
Posts: 22359
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.7


Message 94 of 948 (176605)
01-13-2005 3:38 PM
Reply to: Message 91 by simple
01-13-2005 3:30 PM


Re: the creator factor
cosmo writes:
Also, we mix in some conjecture, and try to project into the distant past that it was always so. Some even try some future conjecture, once again leaving out any creator factor.
I think you must be missing something, because the supporting data is pretty abundant and complete. Could you be specific about what you think is being conjectured?
--Percy

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 Message 91 by simple, posted 01-13-2005 3:30 PM simple has replied

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Percy
Member
Posts: 22359
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.7


(1)
Message 100 of 948 (176626)
01-13-2005 4:16 PM
Reply to: Message 95 by simple
01-13-2005 4:05 PM


Re: into the mystic
cosmo writes:
Well, my feeling is not that man's efforts so far are that inconcusive, as much as they are exclusive. What are we missing? Why do we have the creation time so far off? What went on we have not yet been able, or willing to understand? How could we be misinterpreting what we do have?
Instead of addressing each specific question, let me address just the gist of what you're asking, which seems to be, "How do we know we're right?"
The answer is that we don't know we're right. That's why theories are considered tentative and changeable rather than fixed and permanent.
It is not a valid rebuttal to say, "You could be wrong." We readily agree, as you would have to agree that *you* could be wrong. Such arguments weigh just as heavily on both sides of the debate and so cannot move either side's position forward.
But our position is supported by a wealth of evidence, and so a valid rebuttal of our position can only occur when you have counter-evidence or counter-arguments that undercut our position.
--Percy

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 Message 95 by simple, posted 01-13-2005 4:05 PM simple has replied

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 Message 102 by simple, posted 01-13-2005 4:41 PM Percy has replied

  
Percy
Member
Posts: 22359
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.7


Message 107 of 948 (176652)
01-13-2005 5:29 PM
Reply to: Message 102 by simple
01-13-2005 4:41 PM


Re: be all end all
cosmo writes:
My arguement is that we can't say because decay rates are the same in this thing, that it means it was a long time ago.
If that is what we'd said, then I'd agree with you. But we didn't simply declare that decay rates and the speed of light were the same in the past. We've actually measured them in the past. This has already been described for you in fair detail, so more briefly this time, when we observe a distance star or galaxy, the light arriving here left a long time ago. We are actually seeing the star or galaxy as it existed long ago. We analyze the radio emissions from these objects to determine things like speed of light and decay rates. And we find they were the same long ago and far away as there are here and now.
We have never observed any physical constant to be different anywhere or anytime in the universe. The evidence gathered to this point indicates the constancy of physical constants throughout time and space. While it is possible there are exceptions hiding out there, one doesn't rebut evidence in the hand simply by raising the possibility that there might be exceptions in the bush somewhere out there. Science already takes this possibility into account by declaring that all theories are tentative.
--Percy

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 Message 102 by simple, posted 01-13-2005 4:41 PM simple has replied

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 Message 110 by simple, posted 01-13-2005 7:37 PM Percy has replied

  
Percy
Member
Posts: 22359
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.7


(1)
Message 112 of 948 (176742)
01-13-2005 8:39 PM
Reply to: Message 110 by simple
01-13-2005 7:37 PM


Re: far away not so long ago
cosmo writes:
quote:
We are actually seeing the star or galaxy as it existed long ago. We analyze the radio emissions from these objects to determine things like speed of light and decay rates. And we find they were the same long ago and far away as there are here and now.
Are we really though? I know you think you are. Based on what?
You're giving the appearance of not having read what you not only responded to, but actually quoted. You ask "Based on what?" right after I've explained that "We analyze the radio emissions from these objects to determine things like speed of light and decay rates." We even made direct measurements of the speed of light at remote distances, such as Loudmouth described in Message 56.
There's nothing that obligates you to accept the evidence supporting these conclusions. You can continue to say "Big deal" and ask "Based on what" with no ill effects. But this approach is simple denial, and if you're interested in a discussion then you'll explain what it is about these measurements and analyses that leads you to reject them.
The other issue you haven't addressed is positive evidence for your point of view. As far as I know, there is no evidence that the speed of light has ever varied. This places you in the somewhat awkward position of rejecting a position with evidence while accepting a position with no evidence. You seem to have no better argument than "You could be wrong," which we freely admit, but it is scant comfort for you since it is just true of yourself.
--Percy

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 Message 110 by simple, posted 01-13-2005 7:37 PM simple has replied

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 Message 114 by simple, posted 01-13-2005 11:19 PM Percy has replied

  
Percy
Member
Posts: 22359
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.7


Message 116 of 948 (176908)
01-14-2005 8:30 AM
Reply to: Message 114 by simple
01-13-2005 11:19 PM


Re: far away not so long ago
cosmo writes:
quote:
But this approach is simple denial, and if you're interested in a discussion then you'll explain what it is about these measurements and analyses that leads you to reject them.
My look at loudmouth's link, and anything you or others have said here all seems to say the same thing. That is, that light is constant in speed, and is really coming from far away, where it started out. I wonder what it is you think I am in denial about? Do you think I doubt this, and think light as we know it has changed speed? I have simply said there were others factors so far missed that were at play. I haven't got into what in this thread.
Then I suggest you get into it. Tell us what factors are being missed.
I realize this thread is focused, and probably not a place to delve into ideas not related to 1987.
If we're missing certain factors, aren't we missing them for Supernova 1987A? Aren't these factors therefore relevant to this thread? Please, tell us, what factors are being missed?
--Percy

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 Message 114 by simple, posted 01-13-2005 11:19 PM simple has not replied

  
Percy
Member
Posts: 22359
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.7


(1)
Message 200 of 948 (179340)
01-21-2005 12:53 PM
Reply to: Message 199 by Loudmouth
01-21-2005 12:10 PM


Re: chose your ruler
Loudmouth writes:
quote:
What evidence do we have stars are made of neutrinos, or whatever?
Neutrino stars are inferred from the size and mass of the star.
I sure hope you guys mean neutron stars. Neutrinos are elusive particles that do not interact much with matter.
--Percy

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 Message 206 by cmanteuf, posted 01-21-2005 4:33 PM Percy has replied

  
Percy
Member
Posts: 22359
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.7


Message 204 of 948 (179395)
01-21-2005 4:25 PM
Reply to: Message 202 by simple
01-21-2005 3:57 PM


Re: chose your ruler
cosmo writes:
quote:
So tell me how faster speeds of light fit the evidence
Less time involved. Why? - tell me how it doesn't.
The question was about how faster speeds of light are consistent with the evidence we have. You relied, "Less time involved." You are correct that traveling the same distance over a lesser time yields a higher speed. No one disputes this. What you lack is evidence.
Please understand that it isn't that you are wrong. Take as an example a theory that says all crows are black. Let's say you find every crow you can, and every single one is black. After you've examined many, many crows you can have great confidence in the theory of black crows. Someone could say to you, "Sure, you've seen lots of black crows, but there could still be white crows out there." And you would have to concede that he is correct. But the possibility that you could be wrong is not the same thing as being wrong. Until a white crow turns up, the theory of black crows is still a solid theory.
In the same way, observational and theoretical evidence for the speed of light being a constant is unequivocal and unambiguous at this time. That doesn't mean that evidence or theory might not turn up that the speed of light is not a constant, but it hasn't as of yet. And so this is a very solid theory, because the possibility of contrary evidence, which is true of all theories, is not the same as actual contrary evidence. You can remind us all you like that someday we may find light traveling at different speeds than c, but until you actually find evidence it is a possibility not seriously considered, especially for the dramatic differences in c required for a young universe.
--Percy
Small grammatical improvement. --Percy
This message has been edited by Percy, 01-21-2005 16:36 AM

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Percy
Member
Posts: 22359
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.7


Message 219 of 948 (179441)
01-21-2005 7:11 PM
Reply to: Message 206 by cmanteuf
01-21-2005 4:33 PM


Re: chose your ruler
cmanteuf writes:
I recall reading, approximately a decade ago, about some people who theorized that "neutrino stars" could be the source of the supermassive gravitional fields at the center of galaxies[1]. I assume since I haven't heard much since then about this that there was a flaw in this theory, some observations that could not be properly explained. In other words, the normal progress of science, removing ideas that don't fit the observed evidence. But Google confirms that some people were serious about such things for a time.
I think the Google hits you found for "neutrino stars" may not be referring to actual stars composed of neutrinos, which wouldn't be expected, but are stars which have gone through a stage that produces many neutrinos. There wasn't much explanatory out there, but I did find this at http://www.phys.hawaii.edu/~jgl/nuosc_story.html:
"Neutrinos also play important roles in astrophysical events such as supernovae, which occurs when an old massive star collapses after running out of nuclear fuel. During the collapse the star literally becomes a neutrino star in that neutrinos totally dominate in numbers of particles for a few seconds, and carry off most of the energy from the implosion, more energy than radiated during the entire life of the star."
But maybe there's more to it than that. Anyone know?
--Percy

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Percy
Member
Posts: 22359
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.7


Message 227 of 948 (179714)
01-22-2005 4:47 PM
Reply to: Message 226 by RAZD
01-22-2005 4:32 PM


Re: The Math of the Matter?
RAZD writes:
Sorry, I read that 3 times and still do not know what you are saying.
I believe Cosmo is saying he doesn't want to discuss it anymore, but that he's not conceding because he believes those who know more than him, such as Russell Humprheys (author of Starlight and Time), would be able to provide the necessary evidence and arguments.
--Percy

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Percy
Member
Posts: 22359
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.7


Message 378 of 948 (781864)
04-08-2016 11:56 AM
Reply to: Message 377 by 1.61803
04-08-2016 9:42 AM


Re: time is space and space is time is space is time is ..
I don't think Einstein ever said this. It seems unlikely given that Einstein introduced the concept of spacetime, itself raising questions about simultaneity. I can't find it in Bartlett's or The Expanded Quotable Einstein. Did Albert Einstein say the only reason for time is so that everything doesn't happen at once? mentions a possible source.
--Percy

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 Message 377 by 1.61803, posted 04-08-2016 9:42 AM 1.61803 has replied

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Percy
Member
Posts: 22359
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.7


Message 648 of 948 (823467)
11-10-2017 2:01 PM
Reply to: Message 647 by Stile
11-10-2017 12:43 PM


Re: The Win-Win situation for Science
If I could quibble a bit with your wording:
Stile writes:
Science has been accepting that stars are far away...
It's just about the word "accepting." We have hard evidence for how far away stars are, with the error ranges growing with increasing distance. There's also something called the cosmic distance ladder. It starts with the distances to close stars established through the parallax of Earth's orbit (e.g., Alpha Centauri) as a basis for establishing the distance to more distant stars, and moves outward from there using a variety of techniques.
I'd have the same quibble with the word "accepting" in the other half of your sentence:
...much longer than science has been accepting that software runs on your computer.
I think we have pretty solid evidence that software runs on computers. Unless he's in some facet of the computer industry, my guess is that Starman accepts that software runs on his computer because that's what everyone else thinks, not because he has any personal experience with the details behind writing/compiling/loading software.
Starman wasn't investing any time understanding people's posts. There was no discussion. He was mostly just tossing off one and two sentence content-free responses.
--Percy

This message is a reply to:
 Message 647 by Stile, posted 11-10-2017 12:43 PM Stile has replied

Replies to this message:
 Message 650 by Stile, posted 11-10-2017 2:14 PM Percy has replied
 Message 666 by creation, posted 01-14-2018 11:19 PM Percy has replied

  
Percy
Member
Posts: 22359
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.7


(1)
Message 651 of 948 (823483)
11-10-2017 4:58 PM
Reply to: Message 650 by Stile
11-10-2017 2:14 PM


Re: The Win-Win situation for Science
Stile writes:
Oh, for sure.
I'm not actually trying to appeal to starman.
More like... using starman's posts as a jumping-off point and then attempting to form some sort of description that would appeal to "someone similar to starman, but looking to learn."
I think there's value in replying to starman's posts.
I don't think there's any value in replying to starman
Yeah, that sums it up pretty well. That's a good approach with some people. You know you're not going to convince them, or even get them to engage, but it sure is fun lining up all the ducks of an argument for the benefit of others.
--Percy

This message is a reply to:
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