Re: The Flat Earth? - Conclusion

Madhudvisah dasa Swami (
Wed, 05 Jul 1995 21:52:57 GMT

Anthony Cox <> wrote:

> (Madhudvisah dasa Swami) wrote:

>>We've been through all this before. It's in the thread if you want
>>to read it. There's no point in going over it again. It has nothing
>>to do with religion at all. It's about relativity.

>I did read it, but I think you did not read what you wrote.
>You are the one who quoted religious texts as your sources.

Where? (Of course I might have put a few quotes from the Bhagavad-gita As
It Is here and there but the argument doesn't depend on them :-)

>Since you do not answer the questions I posed in any of your posts
>I can only assume you have no answer.

We have so many answers... But these days people are asking different

>Take care
>Tony (Jonathan Scott) wrote:

>In article <3s6f2t$>,
> on 20 Jun 1995 12:31:25 GMT,
> Gene Preston <> writes:
>>>The idea I have mentioned here, that relatively speaking, the earth may
>>>well be stationary and the universe rotating around it is valid and there
>>>is no way we can tell what is happening from our point of view. Everything
>>>can be interpreted in either way...
>>This is garbage and violates about every physical law I can think of.
>>What century are you from?
>>....gene preston

>I didn't see the rest of this thread (and given the list of newsgroups
>to which this is going, I'm not particularly disappointed) but this one
>point IS valid. Look up "Newton's Bucket" or "Mach's Principle", or if
>you are into General Relativity, the "Lens-Thirring Effect".

>If you assume that gravity is like electromagnetism, moving objects
>generate the gravitational analogue of a magnetic field, which turns
>out to correspond to rotation (in the same way that the ordinary
>gravitational field corresponds to acceleration). When anything
>moves in this field, it is deflected in the same way as a moving
>charge is deflected in a magnetic field.

>It turns out that if you claim that you are standing still and it is
>the universe which is rotating, the gravitational rotational field
>of the universe causes things to move in strange ways which
>correspond exactly to the Newtonian centrifugal and coriolis forces
>experienced in a rotating frame of reference.

>In this sense, all rotation and acceleration might effectively be
>relative to the universe, and this idea is known as Mach's Principle.
>(It is not clear whether General Relativity fully supports this idea,
>although Einstein very much hoped that it would).

>Of course, we CAN detect rotation locally, and we usually find that
>it matches up with rotation relative to the "fixed stars", so for
>practical purposes we can define what is rotating and what is not
>over a large area of space. However, if we were very close to a
>very large mass, or a very rapidly rotating mass, we would find that
>a locally non-rotating system would nevertheless be rotating
>relative to the fixed stars, and in such cases we could not use the
>simplifying assumption that rotation is absolute.

>Jonathan Scott
> or (Jonathan Scott) wrote:

>In article <3sc148$>,
> on 22 Jun 1995 15:10:00 GMT,
> Kevin Sterner <> writes:
>>In article <3sapbs$>, (David Smyth) writes:
>>> I just know the physicists are going to tell me what I just said is
>>> incorrect - and they are right according to General Relativity. The
>>> pendulum would rotate due to gravitational effects of the rest of the
>>> rotating universe if the earth was stationary. My apologies to
>>> the Swami (even if I still think he did fall out of a very tall tree).
>>Nope, it can't work that way. You were right the first time. If you were
>>at the center of a rotating sphere of matter, there would be no force
>>causing you to begin rotating.

>No-one said you would begin rotating. What happens is that you observe
>centrifugal forces and coriolis forces, which means that there is a
>force outwards from the center, and that things which move in your frame
>experience extra deflection forces depending on which way round they are

>Of course, one would normally attribute this to having a rotating frame
>of reference, but the point is that rotation is NOT absolute; it is a
>locally defined effect which can be simulated by gravitational forces in
>the same way that acceleration can be simulated, only usually much
>weaker (since gravitational sources typically move at much less than c).
>Since it isn't absolute, we can adopt viewpoints where one person's
>rotation is another's gravitational effect, and it seems plausible
>(from Mach's ideas) that what we normally define as rotation can be
>taken to be relative to some sort of average of the whole universe.

>This means that we can choose to describe the universe taking any
>point as the center, but it's just somewhat more convenient to choose
>a point which doesn't have too much acceleration or rotation relative
>to other local landmarks, as that makes the calculations simpler for
>the things we can see around us.

>Jonathan Scott
> or

>>>>>> "Gene" == Gene Preston <> writes:
>In article <3s6f2t$> (Gene Preston) writes:

> >> The idea I have mentioned here, that relatively speaking, the
> >> earth may well be stationary and the universe rotating around
> >> it is valid and
> Gene> there
> >> is no way we can tell what is happening from our point of view.
> Gene> Everything
> >> can be interpreted in either way...
> >>

> Gene> This is garbage and violates about every physical law I can
> Gene> think of. What century are you from?

> Gene> ...gene preston

>I disagree. It is entirely straightforward to take a theory like
>general relativity and *express* it entirely in terms of a stationary
>Earth at the center of a revolving universe. In fact one does not
>need to modify the theory at all. A major part of GR is basically a recipe
>for expressing the laws of physics as deduced in one frame in another
>frame. In particular, we can write the laws of physics as they would
>appear in the coordinate system mentioned above.

>The *reason* modern physicists do not do this is that the resulting
>equations are inelegant (read "horrendous"). Since an extremely
>elegant coordinate-free description is available, Occam's razor leads
>us to the conventional representation.

>Tom Clune
>Work: JILA, Campus Box 440 Home: 4860 Meredith Way Apt. 103
> University of Colorado Boulder, CO 80303
> Boulder, CO 80309 (303) 545-6482 (machine)
> (303) 492-7851 (Office A-504)
> (303) 492-8769 (Lab)
> (303) 492-5235 (Fax)
>------------------------------------------------------------------------------ (Jonathan Scott) wrote:

>In article <>,
> on Sat, 24 Jun 1995 09:31:03 GMT,
> "Brian Portlock" <???@???> writes:
>>In article: <CLUNE.95Jun20092538@pasta.colorado> clune@pasta.colorado
>>(Thomas L. Clune) wrote:
>>> I disagree. It is entirely straightforward to take a theory like
>>> general relativity and *express* it entirely in terms of a stationary
>>> Earth at the center of a revolving universe.
>>This is total drivel! Any amateur astronomer with time on their hands and
>>a modest telescope (say 6"-10") can show that the planets do *not*
>>revolve around the earth simply by *looking* at them and observing their
>>phases. ...

>This isn't the point. Choosing a different viewpoint does not affect
>what happens in the universe, but may make it more or less difficult
>to describe what is going on.

>Relative to an observer on the Earth, really crazy things appear to
>happen to the planets and stars, for example due to the rotation of the
>Earth and the fact that we are in a gravitational field (and hence a
>non-inertial frame of reference) but we have learned to account for
>these by using mathematical techniques to transform our viewpoint to a
>frame in which the centre of mass of the solar system is approximately
>at rest and non-rotating relative to the fixed stars. We are hardly
>even aware that we do this normally.

>In a primitive Newtonian description of the universe, it seems that
>acceleration and rotation (strictly speaking, angular velocity) might be
>absolute, in which case there is some sort of universal frame of
>reference in which everything can naturally be described, so that is the
>one we should normally use. Our mental images of the solar system tend
>to be based on this idea of a Newtonian universe.

>Relativity theory shows us that although accelerations and rotations can
>be measured locally (for example using springs and gyroscopes), they do
>not necessarily match up exactly at different points in space, because
>of gravity. We can say that one set of measurements is "right" and the
>other is being affected by gravity, but in general there is no clear
>distinction as to which one we should take, especially when dealing with
>situations where the curvature of space is significant, such as on the
>cosmological scale.

>We can of course use Newtonian laws to ask "what would everything look
>like if I was rotating?". It is well known that a rotating observer
>sees fictitious forces (centrifugal and coriolis forces) that make
>things move in odd ways, which turn out to be perfectly logical when
>seen by a non-rotating observer.

>In relativistic gravity theory, we don't even have to distinguish
>explicitly between rotating and non-rotating frames of reference, as if
>we happen to choose a frame is rotating, these forces arise naturally as
>consequences of the motion of the gravitational sources. (However,
>rotation effects caused by anything less than the whole universe are
>really tiny in practice, since both the source of the potential and the
>object in its field would have to be travelling at near the speed of
>light for the acceleration caused by the rotation to be similar in
>magnitude to the ordinary gravitational acceleration).

>The conclusion is that although some viewpoints make the universe look
>simpler than others, neither acceleration nor rotation is really
>absolute, and our usual way of looking at the solar system and nearby
>stars is just a convenient approximation to the local average motion
>which makes everything approximately Newtonian, and hence easier to
>describe. Describing the universe from the point of view of the Earth,
>or even worse from the point of view of a location on the rotating
>surface of the Earth, is rather complicated, but astronomers have to do
>it all the time in order to know where to point their telescopes.

>Jonathan Scott
> (Tim Thompson) wrote:

>In article <3sltgk$>,
>(Sandra Russell) writes:

>>In <3slsmm$>
>>(Madhudvisah dasa Swami) writes:

>[Swami ...]
>>>You have explained all the observations with the model of fixed stars and
>>>a rotating earth. In your model the rotation of the earth causes the sun,
>>>the planets, the moon and the stars to rise and set every 24 hours. My
>>>point is it could well be [and we have no way of telling] that the earth
>>>is fixed and the whole universe is rotating around it every 24 hours...

>[Steve Harris using the "nom de plume" Sandra Russell ?? ...]
>>Yeah, but if the Earth doesn't rotate, how come the plane of swing of a
>>Foucault pendulum at the pole does? And how come this pendulum plane
>>"rotation" period at a pole matches the rotation of the stars, and not
>>that of the moon or sun? Coincidence?

> If I may interject momentarily from the audience, the Swami
>is referring to "Mach's Principle". This is the solution proposed by Ernst
>Mach to Isaac Newton's "spinning bucket" problem, which eventually made its
>way into general relativity, expressed by way of the principle of

> The point is that the Swami's effect is postulated. Newton's "spinning
>bucket" problem supposes an observer sitting on the edge of a spinning
>bucket of water. The surface of the water will be curved, even though the
>bucket and the water are spinning at the same rate, and therefore at rest
>with respect to eact other. The non-spinning bucket water has a flat
>surface, and the water and bucket are at rest with respect to each other in
>this case as well. Newton considered the problem: what if the bucket remains
>still and the universe rotates around it? Will the water surface be curved,
>as is the case if the bucket spins, or flat, since the bucket is not spinning,
>the universe is?

> Newton had no answer that I am aware of, but Ernst Mach *postulated* that
>the water surface would be curved, that the two situations *must* be entirely
>equivalent in every observable way. If one accepts Mach's postulate, than all
>of the pendulum questions are easily and obviously answered. Einstein borrowed
>this notion for his principle of equivalence, that being at rest in a
>constant gravitational field is observably equivalent to accelerating at a
>constant rate (observed locally).

> My point is that the matter is not so obvious, and really contains some very
>profound philosophy. However, it should also be pointed out that this has
>nothing I can think of to do with whether or not the Earth is flat (I have
>personally observed the fact that it is not flat anyway).

>Timothy J. Thompson,

>California Institute of Technology, Jet Propulsion Laboratory ...
>Earth & Space Sciences Division, Terrestrial Science Element ...
>ASTER Project Atmospheric Corrections Science Team ...
>Vice President, Mount Wilson Observatory Association ...
>Board of Directors, Los Angeles Astronomical Society.

Thank you. Hare Krishna!

Madhudvisah dasa Swami

All glories to His Divine Grace A.C. Bhaktivedanta Swami Prabhupada!