Funniest snake oil theories

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#1,302
Obviously.
You can also conclude that you're not a 'real objectivist'.
Typical subjective behaviour is reverting to fancy words, as a last resort, btw.

I was raised from day one with rational arguementation, and arguementation in my parental home was War, whatever means allowed to reach the goal. Most outsiders found that highly aggressive and very intimidating.
For me it's just a mental exercise and a game.

From day one, outside the house, I was raised with a hammer.
Out on the streets, I turn intimidating and highly aggressive within the blink of an eye, If so required.
On the web, I'm just a playful joker, and shake a fist full of languages out of my sleeve, I don't get excited or intimidated by letters and dots.
Reason I'm King of the Congo on any live chatroom.

But if you fancy a psych war game on an audio forum, free-style, ready when you are.
 
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#1,303
Pano said:
That's great Jacco, but did you or your friends directly experience the curvature of the earth? If so, how?
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We used to all the time. If you were looking for an aid to navigation and you were near sea level you might not see it see it, go up to the bridge and look again.

Also, when in the city of Edmonton, at ground level you can't see the mountains. Go up a few floors in any downtown tower and voila!
 
#1,306
jan.didden said:
If you look at a mirage, you can only conclude that the earth is concave 😉

jan
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a mirage over land, is the reverse of what happens over water. the distortion/refraction is due to air temperature gradients (and thus pressure) over desert or hot land, its hot at the ground with a gradient with altitude. over water its cool at sea level and warmer above.

without the refraction, at eye level, the horizon is only ~5km away (just how much curving of the earth do we expect to see with a 5km radius?). With refraction and over water, the temperature gradients/pressure vary wildly with weather conditions and can increase it (with calm, cool conditions), to allow hundreds of km, as the light can literally follow the curvature of the earth. rumour has it it can get so extreme that it bends more than the curve of the earth. but as your gaze is cast up (or you climb a boat tower), the temperature in the air you are looking through rises and the curvature changes along with it. the light can almost literally blow in the wind with air currents/temperature.

so SY, i'm afraid I dont buy someone being able to accurately calculate it unassisted over water, as its so variable. its not unusual to see 20% variance with normal weather shifts, but it can be much more extreme than that and I dont know about you, my onboard barometer simply isnt that accurate. there are all sorts of calcs online, some claim accuracy to a high degree, but I dont buy it over water, the conditions are just too variable.

this is a separate thing again to the effect caused at the boundary of the atmosphere.

yes the curve is part of the effect, but over water its amplified.
 
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#1,307
i'm sure jacco will know more about this than me, I dont have my sea legs, but there is far from a consensus, particularly over water. about the only thing people seem to agree on is its rather hard to predict/calculate with any degree of accuracy
 
#1,312
jacco vermeulen said:
Navigation 101 :

1 Nautical Mile = 1852 meters = 1 Minute (equator longitude)

Take away your GPS, take away your radar, take away the sun, do look at your onboard barometer and your log, but please tell me where you are 3 weeks later.
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the claim was, accurately calculating the distance to the horizon over water, using visual cues. yes barometer at a minimum, but that still only tells you the local pressure. is there another way?
 
#1,315
mr_push_pull said:
Moon landing anyone?
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are you really confused? can you really be thinking i'm claiming the planet isnt curved? the pages I linked, specifically these. this site is referenced at numbers of universities and has very exhaustive content. I speak only of an illusion, which makes much direct observation pretty unreliable at best. It does not speak of anything more than an illusion, I dont claim it reaches any further than that. it also varies wildly in its effect depending on where you are, what time it is, what latitude, what temperature; so blanket statements dont hold true.

Variable gradients

Unfortunately, the refraction varies considerably from day to day, and from one place to another. It is particularly variable over water: because of the high heat capacity of water, the air is nearly always at a different temperature from that of the water, so there is a thermal boundary layer, in which the temperature gradient is far from uniform.

Worse yet, these temperature contrasts are particularly marked near shore, where the large diurnal temperature swings over the land can produce really large thermal effects over the water, if there is an offshore breeze. This is particularly bad news for anyone standing on the shore and wondering how far out to sea a ship or island might be visible.

It gets worse. While the dip of the horizon depends only on an average temperature gradient, and so can be found from just the temperatures at the sea surface and at the eye, the distance to the horizon depends on the reciprocal of the mean reciprocal of the temperature gradient. But the structure of thermal boundary layers guarantees that there will be large variations in the gradient, even in height intervals of a few meters. This means that on two different days with the same temperatures at the eye and the water surface (and, consequently, the same dip), the distance to the horizon can be very different.

In conditions that produce superior mirages, there are inversion layers in which the ray curvature exceeds that of the Earth. Then, in principle, you can see infinitely far — there really is no horizon.

Of course, we all know that visibility is limited by the clarity or haziness of the air. And the duct that (in principle) might allow you to see around the whole Earth doesn't really extend that far; it typically exists for some limited region, perhaps a few tens or a few hundreds of kilometers.

So the nice-looking formulae for calculating “the distance to the horizon” are really only rough approximations to the truth. You can consider them accurate to a few per cent, most of the time. But, occasionally, they will be wildly off, particularly if mirages are visible. Then it's common to see much farther than usual — a condition known as looming.
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^^ from vv
Distance to horizon

atmospheric glossary

atmospheric refraction phenomena

terrestrial and astronomical refractions

also at sea, the horizon is influenced by the wave crest, if you are at sea level, this is significant.

so you can see, this is not a simple observation with easily predictable results
 
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#1,316
qusp said:
irrelevant to what I posted
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OK maybe i was too quick, i've done enough reading tonight though and the above website is bloody hard on the eyes with wide walls of text.

thanks though, I do find this interesting and I do appreciate any links. i'll have a look in the morning

same with you jacco, I expected to get some good feedback from you, given your study and maritime/engineering etc. appreciated.

i'm far from claiming authority here, but there would seem significant barriers to proper observation without assistance
 
#1,317
As so many others here, you talk a lot, but listen/read little.

1 : A ship has a Compass.
2 : A ship has a Log.
3 : Travel due South.
4 : Shoot the sun on day 1 and on day 2
5 : You can calculate earth sphericity

Hint : 1 Nautical Mile = 1 Minute
 
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#1,318
jacco vermeulen said:
As so many others here, you talk a lot, but listen/read little.

1 : A ship has a Compas.
2 : A ship has a Log.
3 : Travel due South.
4 : Shoot the sun on day 1 and on day 2
5 : You can calculate earth sphericity

Hint : 1 Nautical Mile = 1 Minute
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hmm, no jacco, i'm sorry but that is a completely false characterisation, here, if anything i've read too much. what you speak of is not a direct observation of the earths curve, its a calculation of the earths curve, using observation/s over time (including prior experimental knowledge) and tools. I will not argue that, but that is not the same thing.
 
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