New answers tagged

1

The network topology you want is a tree. Earth is the trunk. Branches split off at Alpha Centauri. Each branch may split into as many branches as it likes, but they cannot connect to other branches. What this means, practically, is that any world is allowed to send wormholes to any neighbouring solar systems that does not have any wormholes yet. But they are ...


2

The classic Traversable Wormhole FAQ goes into wormhole networks in some detail. Essentially, a wormhole network defines an "Empire time" of mutually spacelike-separated points which have, thanks to the wormholes, a shared simultaneity. Creating such a thing without violating the CPC would require some amount of planning; the FAQ suggests sending ...


0

Wormholes Pairs Take a Lot of Time to Set up Suppose you want to create a wormhole pair between here and Andromeda. The only way is to take two nearby regions of space (which are already entangled with each other by virtue of being next to each other ) and push them apart until one reaches Andromeda and the other reaches here. The bridge takes 2.5 million ...


2

The simplest solution is to assume that the 'laws of physics' including those pertaining to the creation of wormholes (WH) prevent anyone from using WH that violate the chronology protection conjecture (CPC). As as a result the CPC is no longer a conjecture but rather a fundamental principal of physics. You can even 'write' into the background of your story ...


3

We know of quite a few planets with long days (Mercury has a longer day than its orbital period), but I think that Venus is most similar to what you're looking for. As you probably know, Venus is known for extremely harsh conditions on the surface with respect to pressure and temperature. But it also has wind speeds that can be up to 85 m/s and circle the ...


0

It has been proven that, given that wormholes exist and they connect two regions of space instantly, you can hurt the Chronology already with a single wormhole. Check out this episode of Sean Carroll's Mindscape podcast where he explains a lot better than I could ever do: https://www.preposterousuniverse.com/podcast/2020/11/23/124-solo-how-time-travel-could-...


0

I am not sure there is a problem. No need to blow anything up. See EDIT at the end for a more formal explanation. Your assumption is that traversing a wormhole does not take as long as making the same trip by light speed. This is NOT a given. A wormhole between here and Alpha Centauri, for instance, could take 4.4 years to traverse, whether through a ...


2

Smudgy Brown. Bloodstains can last myriads of years; but that deep lustrous red of fresh blood doesn't hold up at all well: they end up a kind of dull rusty brown. We have plenty of bloodstained articles from Lincoln's deathbed, for example. Move back a few more centuries, and we see in the Royal Armory Museum in Sweden the blood soaked shirt of Gustav Adolf....


6

As others pointed out, the premise to your FTL engine arises from a misunderstanding of the article and under the hard-science constraints would not be feasible. You are correct in that the article is proposing that the permittivity and permeability of free space arise from virtual particles. However, it appear there is a misunderstanding of the meaning and ...


3

hard-science = NO Currently, we describe particles by their speed compared to the speed of light using the light-cone: Light that moves with the speed of light is light-like. The totality of events that create such particles lies on the surface of a cone of past and future, both crossing in the point of "now" (the spectator). Anything on the cone ...


-1

Non science answer coming, as I have zero knowledge in this area. Instead I will wave my wand and say 'a wizard did it!' by offering the following: maybe the humanoid can do something consciously to activate the extra eye ball features? Like say, if he holds his breath, and his blood pressure begins to rise beyond a certain point, it activates a cooling ...


3

There is a lot going on in your question. Also, as pointed out in the comments, the wavelength you choose matters a lot. If you look up the absorption spectrum of water, you will see that there is a blue green window where our eyes are optimized (visible spectrum ~ 400-750 nm), once you start going much beyond the red the absorption increases dramatically ...


2

Since it is hard-science then answer is no, it is unreal By current concept "speed of light" is not determined by any constants. It is a fundamental constant c of space-time by itself. Even light does not define this constant. It just happens so that light is traveling with this speed (because it is "massless"). It means that changing $\...


7

FRAME CHALLENGE: A mechanical clock that will continue to operate over time comparable to the duration of the human species is impossible to design with current knowledge (especially under a "hard science" tag). BUT: The clock you desire already exists, and predates humanity, though we only learned to read it with high accuracy within the past few ...


7

Mechanically impossible Every interaction between two parts incurs friction. Friction is a force that transfers kinetic energy into thermal energy aka heat. The transfer of kinetic energy into thermal energy is a net loss of kinetic energy and means you need to add kinetic energy to keep the system moving at the same speed. This is due to Newton's laws and ...


15

...Could work without human intervention for many tens, and even hundreds and thousands of years... Impossible (based on any science I'm aware of) Even Hillis' clock won't run without human intervention for anywhere near its lifespan. The orbital speed of the earth changes, and that affects timekeeping. [1] The rotational speed of the earth changes, and ...


8

The question has been already asked and answered here Found an article that used a simple analytical modelling to determine how high a mountain can be. Reference Based on simple physics, tallest a mountain will be on Earth is ~10 km. This is based on: Simple cone shape for the mountain. Vol ≈ $r^2 h$ Based on weight of the mountain: Weight W ≈ $\rho g r^2 ...


1

Depending on surface area exposed (think fine granules), if you oxidize it that fast, it may not just burn — it may explode. My “hazardous materials“ warning source: https://nj.gov/health/eoh/rtkweb/documents/fs/0528.pdf


2

Add Humidity, Salt Water and a little Acid Rain What we're talking about here isn't really oxygen dependent, we can speed the process up by other means. Salts and humidity will speed up the reaction rate, and the acid will help by deteriorating any protective oxide layers. This should have the desired effect without changing your oxygen concentration, which ...


13

I assume you are out in the air, and we are talking about copper clad roofs as below. https://en.wikipedia.org/wiki/Basic_copper_carbonate I was interested to read that verdegris (as I would call this roof) can be various insoluble copper salts - basic copper carbonate, copper acetate and copper chloride. So the Statue of Liberty probably has a lot of ...


31

You won't get it oxidising that fast even in 100% oxygen. I found a source which compares the oxidisation rate of copper at varying temperatures, humidities, and oxygen concentrations. From conclusion section: While oxygen pressure did not affect the oxidation rate of copper, the rate was increased with increasing water vapor pressure due to the increased ...


2

Equilibrium assumption. Once you have the heating power generated inside, $\dot E$, a reasonable way to calculate (or at least approximate) the surface temperature, is to simply assume that: all the power generated by the tidal heating, is radiated outwards and lost to space. Why assumption is reasonable. Note such assumption is indeed reasonable: assume the ...


3

Planets can have tails. But I am skeptical about a gas giant. Comets have 2 kinds of tails: a tail made of dust left in the wake of the comet, and a tail of ionized gas blown off by the solar wind. It turns out that Venus (and theoretically also Mars) sometimes have ionized tails caused by the solar wind. See this page on the ESA website. For Earth, which ...


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