Gian Domenico Cassini, geocentrist. He objected to:

1. The universality of Newton's inverse square law of gravity.
2. the finite speed of light
3.Tycho's model of geocentricity

He used an interesting sytem of ovals instead of ellipses to explain planetary motion.

http://www-history.mcs.st-andrews.ac...s/Cassini.html

His son Jacques was apparently also a geocentrist
http://www-history.mcs.st-andrews.ac...i_Jacques.html

Just goes to show that even smart people can be amazingly wrong, not to mention stubborn. Cassini probably had non-scientific reasons for objecting to these three well demonstrated and observed phenomena and chose, wrongly, to reject them.

Fermi was once asked what Nobel winners had in common. His response, "Nothing, not even intelligence."

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"I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind." - William Thompson, 1st Baron Lord Kelvin

"If it was so, it might be, and if it were so, it would be, but as it isn't, it ain't. That's logic!" - Tweedledee

This isn't right. This isn't even wrong. - Wolfgang Pauli

Of course, dumb people are much more likely to be wrong, such as some geocentrists who remain geocentrists to this day.

Cassini pere was 62 years old when Newton's Principia was published. It's not too surprising that he resisted it. Newtonian gravity was controversial for some time because of the need for action at a distance, kind of the moral equivalent of not having a mechanism for continental drift.

Newton was also in competition with French philosopher Rene Descartes (of "cogito ergo sum" fame), who had his own theory about how the planets moved. It's not too surprising that a French astronomer would treat an English theory with skepticism.

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Everything I need to know I learned through Googling.

what i've read so far in this thread.. the prior 3 or 4
seams like Wise Astrology to me
now about the A. predictions that tomorrow {Sunday}
the BA will be accessable {up & running} i say nothing.

Geocentrists (with a G) might be dumb. But geocentrists (with a g) cannot be dumb, unless you want to call Albert dumb as well!

It's all about the preferred frame of reference. Many things are easier to deal with when using a geocentric reference frame. Other things are easier with heliocentric or other planet-centric frames, and I think even barycentricity is useful for some things.

Who's Albert?

That dude with the bad hair. Some start-up who wrote some equation or some other nonsense that cleared the way for this thing called the "Ahboomb". Oh yeah, also wrote a theory on a General Relativity. I never knew this general, sounds like a real jerk.

:wink: Tongue has been placed firmly in cheek.

That was the 1600's and one man's opinion. How does it have anything to do with the nature of current scientific knowledge (other than the historical aspect)?

In other words: So what?

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...And that, my liege, is how we know the Earth to be banana-shaped. --Sir Bedevere

Yul brings this up because Cassini was an astronomer who did quite a bit of good science, including discovering the gap in Saturn's rings which bears his name.

This is a common geocentrist/creationist tactic: make it seem as if famous scientists agree with them, when in fact the point made is quite the opposite. It's always long-dead scientists from a different age, when things were quite different than now. They never seem to be able to bring up a name that's modern, unless they actually talk about how Einstein believed in God. Of course, many scientists believe in God. However, very few believe in a literal Bible, which is what Yul is trying to support.

Incidentally, Yul, a short rejoinder which is cryptic and not particularly on-topic is not what I would call real participation in a thread you started. I am losing my patience with your tactics.

For someone who claims to be religious I see you have no problem taking names in vain. If you had asked Einstein if he believed a geocentric universe was valid he would probably have laughed you out of the room. You can't take the part of special relativity that states there are no preferred frames and then argue that a geocentric frame is the only one that is valid. What part of NO do you not understand?

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"I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind." - William Thompson, 1st Baron Lord Kelvin

"If it was so, it might be, and if it were so, it would be, but as it isn't, it ain't. That's logic!" - Tweedledee

This isn't right. This isn't even wrong. - Wolfgang Pauli

Geocentricity is the idea that the Earth is the center of the universe in an absolute sense.

geocentricity is the idea that the Earth is as much a center as anywhere else in a primus inter pares relativistic sense.

The latter currently cannot be refuted. The former, although immensely unpalatable to many may yet be correct, but cannot be confirmed without going outside of the universe or by obtaining MM fringes away from the Earth.

You're still tried to have your cake and eat it too. First among equals indeed. If the Earth is as much a center as any other place, you need to give a reason why it should be singled out. In the absence of a scientific reason for favoring the Earth frame (which there is not) you're reduced to an argument from faith. Believe that if you want to, but stop trying to argue that science proves it. If no frame is favored, the universe has no defineable center. Quod Erat Demonstratum. [-(

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"I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind." - William Thompson, 1st Baron Lord Kelvin

"If it was so, it might be, and if it were so, it would be, but as it isn't, it ain't. That's logic!" - Tweedledee

This isn't right. This isn't even wrong. - Wolfgang Pauli

I really think that the galaxy UGC 10214 (the Tadpole) is amazing. It too is as much a center as anything else so I think I like Tadpolecentricity .... oops ... I mean tadpolecentricity more than geocentricity.

Yul, "geocentricity" as you've defined it is meaningless. Pointing out that a specific reference frame is as valid as any other - and thus giving that reference frame its own special "icity" name is about as profound as any creature on Earth strutting around shouting "I've got DNA".

But thanks for clarifying the distinction between Geocentricity and geocentricity. That should help us avoid miscommunication.

If the universe is finite, it has a center. If as Birch holds it has a rotation rate of 10^-13 radians/year, it has a center. Geocentrists (with a G) hold the rotation rate to be 2pi radians/day. If the universe is infinite, then it is acentric or polycentric, then this includes geocentric!

Sounds like Geocentric is the not-held-anymore-for-a-good-reason that the Earth is the true center of the universe and geocentrism is a meaningless term.

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Hwæt! We Gardena in geardagum,
þeodcyninga, þrym gefrunon,
hu ða æþelingas ellen fremedon.

Yul: "If the universe is finite, it has a center."

Nope. That statement is incorrect.

Hmmm, I don't think that would work, it would create uncertaity about the meaning of the word in a text.. And you are supposed to capitalize the first letter in the first word in a sentence, regardless of how the word is written elsewere... And then you have the problem with speaking the words, how would someone hearing the words know the difference?

The only possible meaning I see in what you say, is that you mean group or organisation when you write "Geocentricity", but that is not a normal form of a group name, and a group name would mean the same as the word in normal use..

So, I just does not understand how one can have different definations like this, that would only create problems, since most readers wouldn't know the difference... I would suggest one use a different word instead...

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Game over, you lose, we hope you enjoyed playing the exciting game of Thermodynamics...

I've posted this before:

The struggle, so violent in the early days of science, between the views of Ptolemy and Copernicus would then be quite meaningless. Either CS could be used with equal justification. The two sentences, 'the sun is at rest and the earth moves,' or 'the sun moves and the earth is at rest,' would simply mean two different conventions concerning two different CS. -- Einstein and Infeld, The Evolution of Physics, p.212 (p.248 in original 1938 ed.)
Special relativity does not state that there are no preferred reference frames--it is general relativity that does.

The argument is, that general relativity shows that geocentricity is valid. Thus, our physical arguments against it are not valid. They do not claim that general relativity insists that geocentricity is the only valid frame.

It is quite possible that general relativity is wrong and there is a preferred reference frame. Personally, I doubt that it is the geocentric frame, but I am reserving judgement until we find evidence of a preferred frame.

I think we have all agreed on these points.

1. A geocentristic frame of reference is allowed by general relativity and often used (IE when observing the night sky here on Earth) by astronomers.

2. A Geocentristic Universe, on the other hand...would not work. The forces involved to make the Universe revolve around Earth would have to be magical in nature to make it function. Imagine the upkeep.

I'm still wondering why people are pushin for a physically Earth-centered Universe. The egos of those people must be getting massive and dense enough to start hydrogen fusion.

I disagree strongly with the second one.

Except I do think that general relativity is close to magic.

"By the first years of the 20th century, astronomers using very clever statistical tools had found that the universe, as we recognized it, was indeed finite. We were sensibly near the center" (James Trefil, "Big Bang Physics from before the First Millisecond to the Present Universe" p61)

To take this thread back to the origin. In my initial reply I mentioned that while brilliant in one area, scientists have no monoply on intelligence in others. A couple of examples have come to mind

Fred Hoyle: Great astronomer, lousy biologist. Proposed the theroy that life on Earth was seeded by DNA from asteroids, and that this process continues. Now being used by cranks to explain where every new disease (e.g. SARS) comes from.

Phillip Lenard: One of the first Nobel prize winners in physics. Was a virulent anti-semite, became an ardent Nazi, and was busy denouncing quantum mechanics and relativity as "Jewish Physics" during the war. Wrote the only physics text the Nazi's approved with the wonderful title "Aryan Physics."

William Shockley: Co-inventor of the transistor and Nobel winner (together with Brittain and Bardeen). Founded the semiconductor industry. Now better known for his racial superiority theories. (On a side note, I met Bardeen during my student days at Illinois. A kinder man you'd never know. How he put up with Shockley I'll never know).

All of this is perhaps unfair to Cassini. He was a man of his time and disagreement with Kepler and Newton then was not necessarily thick skulled. Still, astronomy has validated their theories on orbital motion and, presumably, rejected his.

__________________
"I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind." - William Thompson, 1st Baron Lord Kelvin

"If it was so, it might be, and if it were so, it would be, but as it isn't, it ain't. That's logic!" - Tweedledee

This isn't right. This isn't even wrong. - Wolfgang Pauli

And by the end of the 20th century astronomers realized that they were wrong at the start of the century. that the universe was, indeed, infinite and had no center. I'd come up with quotes to support that, but it's Sunday morning, a nice day, and I'm enjoying my coffee too much to go digging through my old textbooks.

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"I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind." - William Thompson, 1st Baron Lord Kelvin

"If it was so, it might be, and if it were so, it would be, but as it isn't, it ain't. That's logic!" - Tweedledee

This isn't right. This isn't even wrong. - Wolfgang Pauli

Care to elaborate? My mind is not functioning at a very good capacity...S/N ratio too skewed...any humor meters have been turned off to save energy.

We're talking about an era when astronomers believed that the Milky Way Galaxy was the universe.

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Everything I need to know I learned through Googling.

Oh for criminy's sake, Yul, that quotation is grossly out of context. I believe Trefil was talking about Jacobus Kapteyn making star counts and mapping the "Universe" that way. What he didn't know is that the Milky Way is not the whole Universe, and that dust and gas blocks our view, so that from anywhere in the Milky Way you'd think you were near the center.

Posting something like this is really, really bad form.

Could you explain that? Thanks.

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"Most editorials are written by people that love to argue but got kicked off debate team for not making any sense." -Seanbaby

General relativity does not require magic in order to "work."

Or am I misunderstanding your question?
If the universe were a toroidal solid, it'd be finite, but its center would be "outside" the universe. In other words, its center would not exist. So, Yul's statement does not follow from first principles. It may be that the Universe does have a center, but just because it might be finite does not imply that it has a center.