I first happened upon this marvel of engineering on this recent CNN Travel video story. Digging around the internet, I then found this late April story on CNN.
London's new see-through Sky Pool is first of its kind:
The Sky Pool is a 82-foot (25-meter) transparent swimming pool stretched between the 10th stories of two residential skyscrapers in southwest London's Nine Elms neighborhood -- and it's only open to the apartment complex's lucky residents[*].
[...] The pool was put through extensive strength testing at the Reynolds factory [in Colorado] before making its journey to the UK by road and sea. It was then lifted into place by a 750-tonne mobile crane, supported by a 50-tonne crane.
[...] "After a series of technical drawings and behavioral analyses, the dimensions of the pool were decided," says the Embassy Gardens website."
With sides 200 millimeters [(7.9 inches)] thick and 3.2 meters [(10.5 feet)] deep, and with a bottom 300 millimeters [(11.8 inches)] thick, the 50-tonne acrylic pool will span the 14 meters [46 feet] between the buildings, with steps and filtrations systems sitting either end, and five modes of lighting to add to the feeling of magic."
[...] "Once you swim off, you can look right down. It will be like flying," says Brian Eckersley, director of Eckersley O'Callaghan.
[*] a two-bedroom unit starts at just over £1 million (~$1.4 million).
Entry on Wikipedia.
(Score: 2) by DannyB on Tuesday June 08 2021, @01:59PM (7 children)
Dyson-swarm. A bunch of smaller fish tanks.
A Dyson Sphere only has 1G at the equator. As you move more North/South-ward, gravity decreases. The ocean at those latitudes, not to mention the atmosphere, would float into the center of the sphere where you may not have intended it to go.
The Centauri traded Earth jump gate technology in exchange for our superior hair mousse formulas.
(Score: 2) by mhajicek on Tuesday June 08 2021, @02:26PM (4 children)
Gravity would slightly increase, not decrease, as you move away from the equator. You weigh slightly more at the poles.
The spacelike surfaces of time foliations can have a cusp at the surface of discontinuity. - P. Hajicek
(Score: 3, Informative) by DannyB on Tuesday June 08 2021, @04:45PM (3 children)
On a Dyson sphere, you are on the inside. Gravity is due to the spin of the sphere. At higher (and lower) latitudes the "pull" of the "gravity" (due to spin) is at an increasing angle from "straight down" where you are standing, and at lower and lower force as you near the poles. At a pole the force is zero and at 90 degrees from "down" (eg where you are standing).
The Centauri traded Earth jump gate technology in exchange for our superior hair mousse formulas.
(Score: 2) by mhajicek on Wednesday June 09 2021, @05:12AM (2 children)
Dyson spheres are built around stars, which have gravity. Yes, you could spin it, to bring effective gravity to or below zero at the equator, but then it would be unbalanced and require even stronger materials. Gravity at the poles would still be full force in either case.
The spacelike surfaces of time foliations can have a cusp at the surface of discontinuity. - P. Hajicek
(Score: 0) by Anonymous Coward on Wednesday June 09 2021, @07:50PM (1 child)
Gravity from the star yes, but that would pull you into the "sky" of the Dyson sphere. Even with the massive structure of the sphere itself the gravity inside would be zero because the rest of the sphere not directly under your feet would exert an equal force. So centrifugal fake gravity is all you could use unless we figure out some better science.
(Score: 2) by mhajicek on Wednesday June 09 2021, @09:57PM
You are assuming the observer to be on the inside, which makes no sense. You could only stand on the inside if it's spinning faster than needed to cancel it's weight, and then only near the equator. That would make most of the sphere useless. Spinning it would also require far stronger materials, making it even less practical. Make it stationary, and you only need moderately magical materials, and you can use the whole outside of the sphere.
The spacelike surfaces of time foliations can have a cusp at the surface of discontinuity. - P. Hajicek
(Score: 3, Insightful) by PinkyGigglebrain on Tuesday June 08 2021, @05:45PM (1 child)
Assuming it is rotating to create centripetal force to simulate gravity.. Which would not be necessary for the sphere to perform it's primary purpose of collecting all possible energy from the star it encloses. At best it would only need enough spin to stabilize it's position around it's enclosed star, which wouldn't be anywhere the speed needed to simulate a 1G field.
If a mega structure was needed for habitation then a ring would be all that would be needed, much simpler to build, less material needed and you wouldn't have to worry about the structural issues of having the Dyson sphere's "North" and "South" regions "hanging" over the parent star with zero outward momentum to keep them from trying to fall into the star while the equatorial zones were trying to fly away from the star at 10m/s due to the spin.
As Larry Niven pointed out in his novel "Ring World" a ring with a radius of 1AU (~93 million miles) and a width of 1million miles would provide nearly 3 million times the habitable area of the Earth on it's inner surface. So it would probably be a long time before anyone complained about over crowding.
"Beware those who would deny you Knowledge, For in their hearts they dream themselves your Master."
(Score: 0) by Anonymous Coward on Tuesday June 08 2021, @06:07PM
> As Larry Niven pointed out in his novel "Ring World"
A little more probable is Arthur Clarke's ring around the earth, with elevators up to it -- in this 2001 sequel:
https://en.wikipedia.org/wiki/3001:_The_Final_Odyssey [wikipedia.org]
Well worth reading if you enjoyed the earlier books in the series.