# Tag Info

3

Can anyone advise on the problems that could be faced OK, this may seem a little weird but your biggest problem is likely to be lawyers and governments. There are a gazillion laws in multiple national and international courts that you'll be colliding with. Some of these laws involved countries and organizations with competing legal claims over the rights ...

3

If want to go fully Schliemann and destroy what you are researching, just build a ginormous ring of dykes around the Doggerbank ahum, now Doggerland. The land will fall dry, destroying much of what you want to research. But, at least you can do it without all those pesky robots and diving gear... *Reclaiming land this way is not as easy as this answer makes ...

5

You can but you shouldn't. You will be destroying a lot of artifacts, many materials that can be preserved underwater will not take drying out well, underwater sites often have BETTER preservation than on land. Which is why modern archeologists often excavate underwater sites entirely underwater. your boxes will allow large areas to dry out before ...

3

A major challenge would be the pressure and weight of water. At 100 meters deep, it is 110 tons per square meter (or 11 kg per square cm). If your contraption sits at the ocean floor, there will be a lot of pressure to force the silt into the air-filled room. You would need to dig the edges deep down into the bedrock at the bottom of the sea to avoid this. ...

5

When building bridges, foundations are excavated by putting concrete walls, joining them and draining the water. This method could arguably be adapted for working in the sea, and probably will be less destructive than dropping a box of concrete over the area. A similar method was used to build the Hibernia platform, an offshore rig that is 80m tall... but ...

3

The only way the edge would spin with an angular velocity faster than the speed of light, is if the momentum from the centre (where I assume you're hypothetically applying the force) is transmitted instantaneously to the very edge. However, since there's no such thing as an instantaneous process in reality, there hypothetically needs to be some transmission (...

9

This question has actually been well studied throughout the years and is closely related to the Ehrenfest paradox. The answer is no-- it's impossible to spin a giant disk in a way such that its outer rim moves faster than the speed of light. First and foremost, it's a rather basic derivation from the postulates of special relativity to show that no object ...

8

Millisecond pulsars! Gravity waves! Imperial to metric conversions! 60 mile diameter disc. 188 mile circumference. 1000 rotations per second = 188 * 1000 miles / second = 188,000 miles/second Speed of light = 299 792 458 m / s = 186282 miles / second. The edge would be going faster than the speed of light; not allowed. Here is a fine and relevant ...

8

I was once where you are. I wondered if it was possible to create a rotating mirrored propeller capable of spinning fast enough to separate particle pairs in the quantum foam in a manner reminiscent of a Quantum Vacuum plasma thruster. The answer is no. The reason is material stress. Basically the maximum stress on a rotating solid disc (or arm) scales as ...

2

The ancient empire who lived there believed that water was the source of all life, and water is the after life. Their despots built huge tombs over the water in order to experience the best after life. The further from shore, the more impressive the tomb. Over generations, the despots built chains of tombs, connected by bridges. Each pillar the resting ...

10

I won't dare sticking my finger into the relativistic theory of rotating bodies, I will just go with the approximation of linear motion, which is valid for infinitesimal rotations. We know that, by relativity, the mass of an object moving at velocity v is increased according to Lorentz factor $\gamma=$$1 \over \sqrt{1-v^2/c^2}$. Therefore, the more the ...

1

Consider Venice... it was built in a (shallow) lagoon by driving wooden piles (tree trunks) into the mud of the lagoon and infilling with 'stuff' that have lasted many centuries. Those were done pre-industrial. Consider the sort of walkways people still build out into the shallow waters of lakes to boat docks... drive wooden piles into the mud of the lake ...

1

To add to the excellent answers already given: your "lake" is marshy and swampy and quite seasonally variable, to the point where barges are not economically viable for year round transport. Your roads and bridges are engineered to remain passible in flood stage, drought stage, and everything in between. As an alternative, you can hamper boats with ...

4

There are places in the real world where roots of rubber fig trees have been trained across rivers and woven together to grow sturdy footbridges. Wikipedia: [Living Root Bridges][1] I imagine to extend something like this to the island would be a lot easier if support pillars are allowable, but with enough time, and a plant whose roots do well underwater,...

2

The Lake Pontchartrain Causeway is 38 km long. Interstate and train bridges have also be built in a similar fashion. An Interstate highway and train tracks running over the same shallow lake. And another bridge ("only" seven miles) built in the same manner.

5

The lake is shallow -- almost a swamp. Three real-world examples of such lakes are the Tulare Lake basin, the Everglades, and the state of Iowa during flood years. Tulare Lake is named for the reed-like plants that grew in much of its area. If San Francisco Bay, the Baltic Sea, and the Persian Gulf were freshwater, they might also be similar lakes. In ...

74

These aren't long-span bridges, but causeways The current record for a single span is just under 2km long, and any single vehicular span over oh, 100 to 200m long is going to require modern truss or suspension bridge technology. However, it has been possible to span far longer distances over water for much longer periods than that, using only pre-Roman era ...

1

If you make your central island the old capital of a long gone empire, then your island sits at the centre of an important crossroad. The empire is long gone, but it influenced settlement patterns and the roads that radiate out from your island are important trade routes between major towns. This is reason enough to keep such routes open. Consider the ...

6

I'm offering this more as storytelling advice than bridge-realism advice, but you can always just leave the origin of these massive bridges a mystery. Tell your players that nobody in the world knows who built the bridges or why. Let them have their theories but never confirm anything either way. Our real world, especially in the time period you mention, was ...

1

Simple answer: objects on the map are not to scale. It's rather an artist impression of the world than an navigator's map. Lord of the rings featured such maps. You can hand-wave these details away in this manner and not have to add intricate details to the history of that world that may entangle you in a web of side-effects of the new explanations.

10

There is a good reason to keep the city on an island in the lake. The reason may be irrational but still good. "This is were the kings or government have been for centuries, it would put their legitimacy into question to move elsewhere" or "this is where the main temple has been since the founding of the state, the god would be angry if we move it." Consider ...

16

A deposit of pumice, a light-weight volcanic rock, near the bridges could help the construction a lot. It's not necessary the volcano exists anymore, the rock could have formed thousands of years ago. Pumice floats on water for a time, making it easy to move even large rocks into place. It will slowly sink when water seeps into its pores, and it could be ...

4

There are potential projects that aim the same thing. Getting to the orbit without rockets by using today's technology. Obviously none of them are using a giant ice mountain. This may provide some insight to these methods: https://en.wikipedia.org/wiki/Non-rocket_spacelaunch

51

Have a look at Rama's Bridge here. It is 48k long and runs between the southern tip of Tamil Naidu and one of the northern islands of Sri Lanka Investigations suggest that a chain of atolls was connected and brought above the water by manual labour. The entire length was above water until the 15th century. Given the right geomorphology and backstory I see ...

7

Starfish Prime's answer touches on this, but all the answers so far seem to be missing the most significant problem with this question. The question assumes that it is possible to "escape Earth's gravity". This is a very common misconception, based on the observation that people in the space station float around as if there is no gravity. The "as if" is ...

10

It being a lake makes the problem somewhat easier from my opinion - any structure in the water would erode much slower then it would in the river or the sea, due to the slower currents. I've looked at the list of longest bridges and dams of the ancient world, and to my surprise, there were actually structures of 2 kilometers in length in both categories. (...

15

Consider an ancient civilization. In the middle Ages, some of the biggest architectures (aqueducts and bridges) were Roman-built, like the Alcantara Bridge. So, in the past history of your world, a big and organized empire left some magnificent relics of its past power, like these bridges. Maybe they were built with the aid of some magic, or just following ...

25

Those bridges are built by connecting together floating rafts or pontoons. They are easy to build and maintain: just chop trees and craft the trunks in the proper shape. Assemble them together, place some anchors along the path. A similar technology was used in Japan to build wooden bridges which could withstand typhoons: during a flood the wooden parts ...

10

This lake on which your bridges are built on may have only recently become a lake. What I mean by this is that what if several decades/centuries ago, this lake was only a canyon/crater (and has only fairly recently flooded) and these long bridges, as well as the islands, are the only parts of the canyon which were above sea level? These long bridges could ...

79

You've already accepted an answer, but aside from the structural issues (and the sheer mindboggling amount of energy it would take to pump all that water up that high), there's another misunderstanding: allow a train running on a train track going up the cone to escape earth's orbit? Getting into orbit isn't simply a matter of getting up really high. ...

13

L.Dutch has already explained why it won't work, I want to add that if you try to do this in any reasonably short amount of time, you will create a huge turmoil. The amount of energy needed to pump thousands of thousands of cubic kilometers of water 3 km uphill (and that's just in the beginning) is staggering mindboggling. A good part of this energy (+ the ...

110

The maximum height a mountain can have on Earth is a tad more than what Mount Everest is high. This is due to the fact that when you increase the height of the structure, you are also increasing the load. After a certain point you will be adding too much weight for what the material can sustain, and the entire structure will crumble on itself. The potential ...

3

The square/cube law is working in your favor, in this case. If you get the initial freezing done for free (assemble in Antarctica), and you go well below the melting point of ice in that initial freeze, you now have a ginormous heat dump (size cubed) with a just-enormous area to receive heat (size squared) you can use passive heat- (well, in your case cold-)...

2

There is no need for the island to be made entirely out of a single material Filling it with air pockets(caves) should help with many problems. There are caves even inside icebergs, so this is not that strange. Those air pockets will help with the floating part (letting the island have more heavier-than-water things), and those caves can serve as habitats ...

3

You can but it is not a permanent structure, it is also a huge waste of money Pykrete dramatically slows melting but it does not stop it, and nothing you can do will stop it entirely just due to osmotic imbalance, so you bases starts shrinking from day one. That said you can probably get several years of use out of it, if you keep it in cold waters and ...

1

Not possible Crete is around 8500 square kilometres so the surface area is going to be a lot bigger than that for an iceberg considered 90% will be underwater. The cooling needs is mind blowing so suddenly you need to generate the energy to cool it and a way of getting rid of the waste heat from both the island and the multiple massive nuclear reactors ...

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