Our sun

Crashfrog makes reference to this thread in his reply: And this just concerns decay rates. When we look deep into the past by millions and billions years by peering far out into space with large telescopes both terrestrial and space-based, we find that processes we observe here on earth were precisely the same long ago.As for tiny data sets, if we just look at geologic ages here on earth, nothing could be further from the truth. Here's just one table of radiometric dating of Greenland rocks from Brent Dalrymple's book The Age of the Earth: Here's another table for the moon (two pages): These datings alone represent a massive amount of data, and yet are only a tiny part of the entire dataset for ages far older than 6000 years..--Percy

1. I don't quite agree with the BA ... it pays not to extend your conclusion too much beyond your data without justification. In the case of dating, even without astronomical data we have an incredible amount of justification that I'd be glad to discuss in the proper forum if you wish. In the case of the shrinking sun argument proposed in the OP, there was no justification for the extrapolation.2. Since we are looking back in time when we look at faraway astronomical objects, and these objects would not have behaved as they did if radioactive decay rates were different, we do have a measurement span that is comparable to the age of the Earth.3. The age of the Earth and its components is measured by many different techniques, many involving radioactivity and many not involving radiactivity. The radioactivity methods use isotopes that decay in different ways. All in all, we have dozens if not hundreds of different and independent ways of measuring the age of the Earth and its parts, and they all agree (a strong indication that they are correct); the Earth is not a few thousand or even a few hundred thousand or even a few hundred million years old. It's about 4.5 billion years old. Well, it depends on what you mean by "remains the same". We have strong evidence that there were no processes operating in the past that are not operating now and vice versa, and we also have strong evidence that the rate of radioactive decay has remained the same. So in that sense, yeah, things are the same. Of course, there have been tremendous changes in the surface of the Earth and the organisms that inhabit it. The Sun burns about 4 million tons of its fuel each second. We better get ready ... we only have about 5 billion years until the fuel runs out! The Sun has noticably changed size, and that has had some effect on life on Earth, over the last 4.5 billion years. We have some evidence of that.

Well, to be fair, all the radioisotope ages are based on "extrapolating" decay rates that we have only known about for about 100 years and have only measured over periods much smaller than that; so if nothing else is considered (in the typical creationist manner) all that data could be thought of as the result of extrapolating over a range about 10⁹ or so larger than the range of our measurements. I'd be suspicious of such an extrapolation without some pretty strong justification.Of course, there are several other factors to be considered, and the justification is so strong that we tend to not even consider it an extrapolation.

I should have been more clear. Yes, do not extrapolate too far beyond your data without clear grounds for doing so, or without being clear about how you are doing it, and not without trying other methods of extrapolation to make sure your answer makes sense.The E. Coli post is an excellent example of this.

So is the sun in fact shrinking or not? I've heard multiple time frames on a cyclical rate of growth and shrinking... I am curious therefore if it does grow again, how?

Yet if the premises used in all the dating are incorrect, then all of the data is incorrect...is it not?

Well, yes, but ...(I like the word you used, "premises", better than the more-often-encountered "assumptions". IMHO it's a more acurrate description.)Many dating methods give an indication when one or more of the premises is not valid; the most popular dating method (concordia-discordia) can often give a valid date even when the samples have been modified after solidification. The only ways to fool all these methods all the time is a miracle or continuously repeated random happenstance that is so unlikely that it's more likely that you would win the grand prize in the lottery 100 times in a row.The only premise that is never checked internally is the premise that radioactive decay rates have remained constant. However, this premise has been checked six ways from Sunday, theoretically and experimentally, over the last hundred-odd years, by physicists who could care less about dating. No evidence has ever been found of any noticable change in decay rates under conditions that are compatible with the existence of the Earth, and any change in decay rates (now or in the past) would have far-reaching implications and effects that we would notice (e.g. melting the Earth).The "creation scientists" are running a shell game con. They point out, rightly, that any method can give the wrong answer under particular circumstances. (They usually pick K-Ar dating, which is more susceptible to error than many other methods, and which is not used much today because of that). Then they switch the shell and claim that this invalidates all dating.However, in order for our age determinations to be wrong, all methods must always be wrong under all circumstances. The only way anybody's ever come up with to have this happen is a massive change in all decay rates, this change being coordinated in just such a manner as to fool all the different methods by exactly the same amount, and must happen in some currently unknown (that is, impossible as far as we know) manner that avoids the heat and radiation problems. The only ways this could happen are a miracle (which "creation scientists" avoid because then it's not science) or if everything we think we know about nuclear phsics is 100% wrong. And we can be pretty darned sure that we know a lot about nuclear physics.In summary, yeah, if the premises are invalid then the dates are wrong. But the premises are not invalid all the time, or even most of the time. Anybody who tells you they have evidence that the premises are always invalid is selling snake oil.

As odd as it seems, no. Aside from the fact that there is no reason to believe that all or any of the premises are incorrect even if they somehow were there are still reasons for thinking that the answers are still correct.Weird eh?Here's the other thing that you have to consider. The premises behind the dating methods are different. There are different decay rates, different decay methods and different measuring methods.Now, if they all agree you have to give due consideration to the possibility that they are right. And this has to be given separately from any of the details of how the answers were arrived at.If you think the answers are wrong you not only have to worry about any assumptions or meansurements or calculations you also have to at least suggest how the answers could agree so well. These answers agree with each other and with know historical dates. Pretty hard to fathom that is.So if the premises are incorrect the answers may well be but because it isn't one premise that everything is based on it isn't knocked down that easily. If the decay rates are not constant you not only have to explain all the measurements made (over 100,000 s of years) to show that they are, you also have to explain how concordant the dates are. There has to be some reason why all the different rates with different mechanisms are all different in the same way.No such explanation has been suggested. That is just one reason why it sounds like it isn't a very useful suggestion.

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Common sense isn't

The Sun is not shrinking steadily. I'm not positive, but it seem likely that it's in the growing portion of the 80-ish year cycle (which troughed in the mid-1980s).From The Legend of the Shrinking Sun - A Case Study Comparing Professional Science
and "Creation Science" in Action (dated 1986), which is well worth reading in its entirety:

quote:

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The discrepancy between these results and the report by Eddy and Boornazian called for a second look at the solar meridian transit data. John H. Parkinson, Leslie V. Morrison and F. Richard Stephenson performed such a re-evaluation and concluded that the trends in the Greenwich data reported by Eddy and Boornazian "are the result of instrumental and observational defects rather than real changes.9 In their judgment, based on the combined data sets of the Mercury transit and total solar eclipse observations, no secular change over the past 250 years was detectable, but a cyclic change with an 80-year periodicity was indicated. In an extensive article published in the Astrophysical journal, R. L. Gilliland confirmed the presence of a 76-year periodic variation in the sun's diameter, but suggested that the data do allow for a very small long term shrinkage at the rate of 0.1 are second per century during the past 265 years.10

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During the past two years, additional papers have been published which reinforce the conclusion that secular changes in solar diameter cannot be confirmed by available data, but numerous oscillatory phenomena have been verified. Parkinson, for example, in a 1983 paper, states that solar eclipse and Mercury transit measurements "confirm that there is no evidence for any secular changes in the solar diameter, with a reduced upper limit. However, there is increased sup- port for an (approximately) 80-year cyclic variation."11 And, according to Sofia et alia, "Solar radius changes are not secular (monotonic and uniform)."12 In 1984, Claus Frohlich and John Eddy reported the results of recent measurements of solar diameter.13 Of particular {sic - apparently some text is missing - jrf} What began as an interesting puzzle in the arena of solar astronomy has been transformed into a "proof 'for recent creation. relevance to the present discussion is the result that during the period from 1967-80 the sun exhibited an increase in diameter at the mean rate of 0.03 are second per year, equivalent to a linear rate of eight feet per hour. Since 1980 the solar diameter has remained nearly constant, with a weak suggestion of decreasing. This behavior is remarkably consistent with the 76-year periodic behavior found by Parkinson and Gilliland, for which a broad maximum would be expected in the mid-1980's.

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Note that several different studies found a cyclic variation with a period around 80 years. I bet the "80 days" you found is a typo.Note also how long it's been since the idea of a steadily shringing Sun was debunked.

Well, if ALL of the premises are always wrong in exactly the right way, then the conclusions are not correct. But I think we're both right.It's difficult to explain in this medium exactly how interconnected the geology and physics and chemistry and paleontology and Lord knows what are, and how what appears to be a few assumptions is really a vast web of interconnected results and conclusions based on a vast array of observations. We tend to avoid absolute statements, always levaing some wiggle room, but the premises are seldom wrong.