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Re: Astronomy and "controlled scientific tests"

Posted: Fri May 25, 2007 7:19 am
by makc
Nereid wrote:In view of how large this gulf* seems to be, it may be worth spending some little more time on it.
You have forgot to include footnote ;)

Re: Astronomy and "controlled scientific tests"

Posted: Fri May 25, 2007 7:21 am
by makc
Michael Mozina wrote:Care to show me what useful things I might do with dark matter or dark energy or inflation?
You can explain the measurements in terms of accepted theories.

Re: Astronomy and "controlled scientific tests"

Posted: Fri May 25, 2007 2:11 pm
by Nereid
makc wrote:
Nereid wrote:In view of how large this gulf* seems to be, it may be worth spending some little more time on it.
You have forgot to include footnote ;)
Thanks (it's nice to learn that at least one person has read my post that thoroughly!).

I've edited it, to add the footnote (= "or how comprehensive the misunderstanding of the nature of modern astronomy seems to be.")

Re: Astronomy and "controlled scientific tests"

Posted: Fri May 25, 2007 2:20 pm
by Nereid
Michael Mozina wrote:
Nereid wrote:You have already been presented with rather a large number of just such tests ..
No Nereid. You don't seem to be able to distinguish between a "scientific test" with control mechanisms, and a pure observation with no control mechanisms, followed by a giant leap of faith into the realm of metaphysics.

If you could shut off your dark matter machine like they shut off the nuclear power plant to end neutrino emissions, then you could call your telescope observations "tests". What you have are pure observations and your own personal "interpretations" of those observations. What you don't have are any *control mechanisms* so they are not "tests", they are just "observations" and "interpretations".
We've been over this, and over it, and over, and over ...

For me, you have established the basis for your views on the nature of modern astronomy (I can't speak for others reading this thread).

That your view is very different from the scientific basis on which modern astronomy rests is also, I feel, clear (to me, at least).

Further, in the terms you have presented it, it seems a weak basis indeed for doing any astronomy. It may even be either so internally inconsistent that no astronomy, as a science, can be done (Sun-ward of ~the orbit of Mercury, and beyond the present positions of the still functioning Pioneers and Voyagers), or so weak that progress slows to a standstill.

In any case, I think it's time to move on.

Re: Astronomy and "controlled scientific tests"

Posted: Fri May 25, 2007 2:34 pm
by Nereid
Michael Mozina wrote:
Nereid wrote: You can?!?!?!?!?

How?
It's really very simple actually. My computer is plugged into a battery backup unit. The battery itself is rated in amps/hour, and the more amps per hour, and the larger the battery, the longer it can run.

When I unplug the battery backup unit from the 110V AC wall socket, my computer is completely powered by the battery, and it's power is measured in amps per hour. If I unplug the computer from the battery backup unit, my monitor immediately goes dark, and my computer shuts down. If I push the buttons on the computer with it unplugged, nothing happens. Miraculously, when I plug it back into my battery backup unit and push buttons, my monitor lights up and viola, I'm back here in cyberspace chatting with you again. Not once have I been able to chat with you with the power turned off on the computer.

The sentence that my astonished comment, and question, refers to is: "I can see that electrons are powering my computer right now."

I don't doubt that you can, and did, do the things you described.

However, none of those things seems to answer my question, or relate to your own statement. For starters, there is no mention of 'electrons' in your actions, let alone to you 'seeing' them do anything ...
Care to show me what useful things I might do with dark matter or dark energy or inflation?
This is a rather new twist ... a criterion, in the MM view of astronomy, for something to be considered scientifically valid is its demonstrable utility to at least one individual of the species, Homo sapiens.

Of course, at one level, this is very easy to answer in the affirmative ... I could make a case that at least part of at least some journalists' incomes are derived from dark matter, dark energy, and/or inflation.

But, somehow, I don't think that's what you have in mind ...

Oh, and I doubt if you're serious in claiming that such a 'utility test' is a valid criterion for judging whether something in astronomy is scientific or not ...

Posted: Fri May 25, 2007 2:48 pm
by Nereid
Earlier in this thread there was some discussion of General Relativity, and of Newton's universal law of gravitation.

Phenomenologically*, the two are very similar - you can get a very nice match between centuries of observations of the planets and predictions from each, for example, with just a tiny subset showing differences that are bigger than the error bars on the observations (the 'advance of the perihelion of Mercury' is one such subset).

Yet they are radically different theories!

Newton's is about a force; Einstein's is about geometry.

So, which is it? Is 'gravity' a force? or geometry?

The scientific approach (one such approach) to answering such a question is to ask "which best matches the relevant, good observational and experimental results?", and to conclude that 'gravity is whatever the theory that matches better says it is'. In this case, given that GR has passed every test, to date, with flying colours (and the Newtonian law failed, in all tests which can distinguish between the two), we can say 'gravity is geometry'.

*Which is just a fancy way of saying "in terms of what we actually observe"

Astronomy and controlled Scientific tests.

Posted: Thu May 31, 2007 10:56 pm
by rodly
There seems to be a lull in this thread, yet not all has been said I'm sure.

I am posting this in this thread because the question and queries that deal with at least four of the items in the first post, and also with the last post by(at the time I composed this)

Unfortunately, the question and the queries and explanations of the questions is long and perhaps tedious, nor are my beliefs tied to it all. It is a question about a conception that I have found no reference to anywhere that I have looked. Whether or not I have exhausted all sources is immaterial from a statistical point of view.

I am placing this question and accompanying baggage without references to any other works simply because I have not found any (and this may be the way it should be). Besides, Copernicus put forth a concept, without a perfect theory of how it could be so. Yet he was right.

The main question is:

Could there be a multiplying effect of the gravity of a body of mass?

By way of explaining what I mean by multiplying effect I imagine the following:

Two bodies of equal mass (called A1, A2), far removed from all other but negligible gravitional effects of other bodies, revolve around their common centre of gravity (or if you will, locked into each other's gravity well at similar positions). The two bodies have used the entirity of their mass to establish this “equilibrium”.

Since these two bodies have used all the gravity that their mass supplies to establish themselves, how would they attract a third body(B) of any size, let alone the one I'm going to conceptualize, without their mass being able to increase its' “attraction abilities” in some manner?

Is the answer to the last question 'The third body(B), travelling on its' way to eternity(or whereever), enters the gravity well(s) of: a) A1 b)A2 c)combined A1,A2 d)none?

(Sorry, I forgot to mention that some of the questions might be multiple choice.)

If either of the first two answers satifies the question to your satifaction skip to the quote at the bottom.

Why would there be a gravity well if both A1 and A2 used up their “attraction abilities” on each other?

If there is a third gravity well (combined A1,A2) that has the power of the sum (or some part of the sum) of the masses of A1 and A2, does this not mean that both A1 and A2 masses have multiplied their gravitational ability? Or have they lost their grip on each other? (or have I lost mine?)

Does anyone have a suggestion that would cause them to choose the answer “d” in the multiple choice question?

Backing up the scenario a bit, I imagine body(B) with a mass equal to either A1 or A2 travelling on a course that will take it through the midpoint of the A1,A2 duality perpendicular to the plane of the orbits of the twain. It is travelling in such a manner that it will pass through the orbital plane and always be equidistant from A1 and A2.

Is there some manner in which body(B) could pass through without disturbing A1 or A2?

If the answer is no, then is the gravity well of B the sole disturbing factor?

Is there some manner in which body(B) could pass through without its manner being changed?

If it is changed then how did the masses of A1 and A2 change it?

That is the last question for now, and if anyone needs to know how this might pertain to the first four items of the original post I will respond later.

Due to the nature of some of the responses that have been posted to this forum in this and other threads I'm including the following quote:
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Fallibilism is the philosophical doctrine that absolute certainty about knowledge is impossible; or at least that all claims to knowledge could, in principle, be mistaken. As a formal doctrine, it is most strongly associated with Charles Sanders Peirce, who used it in his attack on foundationalism, but it is already present in the views of early philosophers, Xenophanes, Socrates and Plato. Another proponent of fallibilism is Karl Popper, who builds his theory of knowledge, critical rationalism, on fallibilistic presuppositions. In recent times, the concept has also been employed by Willard Van Orman Quine to attack the possibility of analytic statements.

Unlike scepticism, fallibilism does not imply the need to abandon our knowledge - we needn't have logically conclusive justifications for what we know. Rather, it is an admission that because empirical knowledge can be revised by further observation, any of the things we take as knowledge might possibly turn out to be false. Some fallibilists make an exception for things that are axiomatically true (such as mathematical and logical knowledge). Others remain fallibilists about these as well, on the basis that, even if these axiomatic systems are in a sense infallible, we are still capable of error when working with these systems. Moreover, according to Gödel's incompleteness theorems, to find a complete and consistent set of axioms for all of mathematics is impossible, That is, even mathematics has its own paradox like the Barber paradox. The theory that it was impossible to know a truth with certainty was the basis of the educational movement lead by people like John Dewey and was called the pragmatist movement.

The critical rationalist Hans Albert demonstrated the impossibility to prove any certain truth even in the fields of logic and mathematics. See his Munchhausen-Trilemma illustrating the hopeless situation to justify all your means to justify any certain truth. Even if fallibilism is inevitable Albert does not fall victim to relativism or scepticism.

Posted: Sun Jun 03, 2007 10:18 pm
by Maddad
On gravity being a force or geometry

I have been reluctant to return to this board. I do not need the fighting, and yet that is what is going to happen if I return. Ok. First, the 92-year-old geometric description of gravity does explain the extra 43 arc seconds per century precession of the perihelion of Mercury's orbit. Force does not.

Force also does not explain our sun bending starlight 88 years ago, but geometry does. Geometry also explains why that starlight redshifts coming out of an intense gravitational field, but force does not. Today we frequently use gravitational lensing in astronomy to get better images of distant objects. Force has no explanation. Forty-seven years ago, Robert Pound and Glen Rebka explained two parts in ten trillion redshifted gamma rays in a 74-foot tall tower with a geometric explanation of gravity; force was unequal to the task. In the same decade, Princeton University scientists explained redshifted sunlight with geometry which force could not address. Eighty-three years ago astronomer Adams detected the redshift from white dwarf Sirius B light which force could not explain but geometry could. More recently, neutron stars have shown even greater geometric redshifts which force says they should not have.

Global Positioning Systems (GPS) are a bit closer to home. Calculating time in Earth’s gravitational field using only force makes these devices gain forty-five microseconds a day, which force does not predict. Geometry from their speed relative to the units on the ground causes them to lose seven microseconds a day. We should adjust those clocks thirty-eight microseconds a day if we reject force as the explanation. Since GPS units must know when they are within twenty or thirty nanoseconds to know where they are within five or ten meters, a 38,000 nanosecond error a day gives the wrong GPS location within about two minutes. Calculating by force instead of geometry, they are wrong by ten kilometers a day.

Posted: Mon Jun 11, 2007 9:11 am
by makc
Maddad wrote:I have been reluctant to return to this board. I do not need the fighting, and yet that is what is going to happen if I return.
the fighting is what drives this board mostly. Otherwise it is way too quiet.