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Astrophysics: How would a fetus’ development change if mother was traveling at relativistic speeds?

I think he means if the room is 80F, then a glass of 15C water warming to 20C will take more time than a glass of 5C warming to 10C (same delta T of 5C, but at different heat differentials to the environment)

Is it true that if the model of solar system off by 1mm the solar system wouldn’t be exist?

Why isn’t Antarctica a more explored place? I know it is verrry cold but there are areas on earth populated with people living there that are insanely cold and people manage. Resources and whatnot are a challenge and I can see why it would be difficult to get people to sign on to explore the Antarctic but this continent is barely explored like at all! If I ask people usually respond with “there isn’t anything out there,” but I keep seeing amazing discoveries of ancient ruins and whatnot all over the world but nothing is ever found in Antarctica because I feel like no one bothers to look. If there isn’t anything out there why don’t we do any testing out there for the big weapons since it’s safer? I could just be ignorant but am I missing something?

The increased gravitational potential energy comes from the work done by the pressure exerted by the ice on the ball as the water volume expands during freezing. The pressure causes the ball to move upward, thus doing work on the ball and increasing its potential energy with respect to gravity. The work done is equal to the change in potential energy, so the increased potential energy comes from the work done by the pressure.

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The water sodium chloride system looks like this. Temperature on the vertical axis, concentrations of water and salt on the horizontal axis. It's called a phase diagram. https://www.researchgate.net/profile/Sayed-Badawy/publication/276999290/figure/fig3/AS:391864646684674@1470439220347/Phase-diagram-of-salt-water.png

Unless it were in a cooler?

Wait, so a glass of ice water will warm faster than a glass of water at 50 degrees? That doesn’t seem right. Are we using different metrics? Like, the glass of ice water will absorb much more heat to get to room temperature but certainly it will stay below room temp longer?

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If you want a very simple visualisation: imagine the soundwave as people, leaving an elevator into a big room. They will tend to spread out in a half circle. Like a soundwave does if it has to pass a narrow slit. The string vibrates the soundbox, and from there, sound goes in every direction.

This lower temperature system would "stay cool longer" because it is colder.

No, it will not. It will absorb environmental heat faster due the higher temperature differential to ambient. The larger temperature difference between the ice-water mixture and the ambient temperature will cause the mixture to absorb heat faster, thus speeding up the warming process.

From either ship's perspective, the Earth is approaching (at the same speed an observer on Earth measures the ships to be travelling at), and the other ship is approaching at a slightly faster speed (which you can calculate with the relativistic velocity addition formula).

But from the ship's perspective, the distance from it to the Earth at any given time is smaller than the distance from the Earth to the other ship. The other ship is approaching faster, but it has more ground to cover. These effects cancel, and the two ships arrive at the same time.

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The energy released from the crystalization goes towards increasing the potential energy of the top of the water.

Freezing water releases energy to the surroundings, usually in the form of heat (the water gets colder, while the surroundings get warmer). It's the same effect as a handwarmer.... when the pack crystalizes, the energy released is absorbed by your hands, which get warmer.

In your hypothetical, (if the ball actually does raise up) I'd expect the water to freeze at an infinitesimally lower temperature than typical at your conditions.

I'd more expect the water to rise around the ball, but certainly can't know until doing it haha.

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> From each's perspective they should arrive at Earth first

What would happen if the winner grabbed a trophy (or whatever) on their way by? Relativity can break simultaneity, but not cause & effect. Thus "local" simultaneity must still be preserved in all reference frames. It's only distant events that different reference frames will disagree on.

> From each's perspective [..] the other would appear to not be moving at all

This would only be true if they're moving in the same direction. But in that case, they can't both be heading towards Earth.

There is a 'theoretically': Tachyons would be able to cross event horizons.

Of course, we have no reason to believe that tachyons exist (and good reasons to believe why they don't), but if you're not careful, they may pop up in numerical simulations (that whole photon velocity being a null vector thing is a bit fragile if you do not take steps to enforce it algorithmically).

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First of all "seriously considering" just means " people are talking and writing about it" not anything concrete.

But even floating on Venus has advantages over gas giants. You have much higher gravity on gas giants. It is much harder to launch out of the atmosphere. The hydrogen helium mix is worse for bouyancy. The planets are much further away. And there is no altitude with decent pressure and temperature.

Bingo. If the string itself was the only thing propagating the sound then a guitar would just be a 2x4 with strings attached.