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Offline Tim Alphabeaver

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Re: Revisiting Bedford Level Experiment
« Reply #60 on: January 30, 2020, 02:47:47 PM »
The whole bumph depends on the assumption that earth is a sphere where R = 6370km
 so use of an imaginary equation K=R/r to quantify any observation falls into the category of pseudoscience .
The introduction of 'K' is clearly just to compare the actual meaningful value 'r' to the globe model's 'R' in order to make the results more human-readable.
You could say instead that when the light isn't refracted, r=infinity, and when it's refracted the same amount as the RE globe curves, it's r=6,371km.
No information is gained or lost here - it's just easier for a person to parse a value of K that's usually -10<K<10 rather than using r, which is [infinity]>r>~0
**I move away from the infinite flat plane to breathe in

Re: Revisiting Bedford Level Experiment
« Reply #61 on: January 30, 2020, 05:23:30 PM »
Did LIGO account for curvature as expected from the pear shaped earth or the oblate spheroid sphere ? That is what I am trying to find out . Which shape did Bob the builder account for ? Apparently neither since he used a ellipsoid model constructed on a mythical centre of the earth. 

An oblate spheroid is a surface of revolution obtained by rotating an ellipse about its minor axis, so it is a form of ellipsoid and indeed it is sometimes called an oblate ellipsoid. They mean the same thing in this case.

We know that WSG-84 is nothing but a mathematical construct in which earths centre of gravity is the starting reference point for the coordinate system .

Yes of course. It's the closest approximation we have for the true shape of the Earth which is also a simply defined mathematical shape. Its accuracy varies depending on where you are, but is perfectly acceptable for GPS etc. For many purposes, a simple sphere would do, but this is just a better approximation.

I mean read this quote from the conclusion on this link https://gisgeography.com/wgs84-world-geodetic-system/
 
It states "Never before have we’ve been able to estimate the ellipsoid with such precision." Ho ho - estimate with precision .

Every physical real world measurement is an approximation within acceptable tolerances, so yeah, estimate with precision. Parts for racing engines are made with high precision, but they're never exact, they are either within tolerance or not.

Where is that centre of gravity on the pear shape /oblate model . Read the links I posted and you will see that is a big problem . There is no centre of gravity .

LIGO constructed its arms plane and level according to normal plane surveying techniques . That's my view .

Well except that the people who built it are telling you they used WGS-84. You have the evidence, you quote from the source. Do you accept it?

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Offline stack

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Re: Revisiting Bedford Level Experiment
« Reply #62 on: January 30, 2020, 09:41:34 PM »
Did LIGO account for curvature as expected from the pear shaped earth or the oblate spheroid sphere ? That is what I am trying to find out . Which shape did Bob the builder account for ? Apparently neither since he used a ellipsoid model constructed on a mythical centre of the earth. 
 
We know that WSG-84 is nothing but a mathematical construct in which earths centre of gravity is the starting reference point for the coordinate system .


I mean read this quote from the conclusion on this link https://gisgeography.com/wgs84-world-geodetic-system/
 
It states "Never before have we’ve been able to estimate the ellipsoid with such precision." Ho ho - estimate with precision .

Where is that centre of gravity on the pear shape /oblate model . Read the links I posted and you will see that is a big problem . There is no centre of gravity .

LIGO constructed its arms plane and level according to normal plane surveying techniques . That's my view .

This may be your view but it is not the view of the Engineers that designed/built LIGO as spelled out in the paper:

"A straight line in space varies in ellipsoidal height by ~1.25 m over a 4 km baseline. At each of the fiducial points, the design ellipsoidal height of the beam tube centerline was calculated using the WGS-84 model with the latitude and longitude as inputs. These heights were used to perform preliminary alignment of the tube sections as the supports were installed during beam tube fabrication on the slab."

So you can basically say one of the following:

- They lied and didn't really survey and construct LIGO taking into consideration a curvature of the earth because there is none
- They took into account a supposed curvature of the earth when they didn't have to because there is none
Not much is known about the celestial bodies and their distances.

Re: Revisiting Bedford Level Experiment
« Reply #63 on: February 04, 2020, 10:35:21 PM »
I still don't get how FEs interpret refraction and how they model it. Rowbotham clearly ignored it, but he doesn't represent all FEs. As far as I can't see the current state of this discussion is that the current theory of refraction assumes a Globe Earth in it, even though those assumptions could be "theoretically" ignored. But still this doesn't rule out that the Bedford canal apparent flatness could be well due to refraction, and this fits nicely with the common idea of FEs to ignore visual proofs.
Quote from: Pete Svarrior
these waves of smug RE'ers are temporary. Every now and then they flood us for a year or two in response to some media attention, and eventually they peter out. In my view, it's a case of "if it ain't broke, don't fix it".