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Kip Thorne: The science of Interstellar

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Re: Kip Thorne: The science of Interstellar

#11

Post by chton »

xxxyy wrote: post #6
chton wrote: post #2

Surely Kip Thorne himself has to realize that he's grasping at straws. A lot of the things he mentions are of the type "in this precise, extremely rare situation it is possible, if we ignore all the other side effects". For example, I'm sure his calculations will be correct regarding the planet orbiting a black hole close enough for relativistic effects. What it also means is that the planet would pass through the ex…

I believe it is possible to set the rules at the real physics level, take 2001: A Space Odyssey as an example. But not if you are forced by Hollywood producers to put all the little pieces that follow inner feelings of the masses. This is what I believe happened to Matrix movies, progressively keeping worse and worse grip on their own rules.

Absolutely, it is possible to claim accuracy, but then you have the hard task of making that actually true. 2001 was better because of that accuracy, but for many movies it's not a good way of doing it. Interstellar could have worked with complete scientific accuracy, or they could simply not have claimed that it was scientific. Either would have been fine.

I agree on the Matrix movies, but they had much more of a free pass already, because the core concepts are so flexible.

Re: Kip Thorne: The science of Interstellar

#12

Post by vacri »

chton wrote: post #2

Surely Kip Thorne himself has to realize that he's grasping at straws. A lot of the things he mentions are of the type "in this precise, extremely rare situation it is possible, if we ignore all the other side effects". For example, I'm sure his calculations will be correct regarding the planet orbiting a black hole close enough for relativistic effects. What it also means is that the planet would pass through the ex…

I liked Intersteller a lot as well, but its plot was horribly contrived in places and the science isn't as good as it was purported to be - even moreso if you include the behaviour of the scientists involved :). The science was certainly better than most other serious sci-fi films though. The real problem with the film is the needlessly long hour of character establishment.

(SPOILER) Rather interestingly, I've seen very little discussion about the christ story in the film - the 33-year-old man, who is also the 'father', who is also the 'ghost'; who disappears presumed dead, only to return; who has the only information that can save humanity (the 'quantum data') and also sacrificed himself to save humanity; and who was helped along by 12 others - one being the questionable [Dr] Man[n] who is weak of spirit. There's a few more other parallels, but the gist is there.

Re: Kip Thorne: The science of Interstellar

#13

Post by chton »

gglon wrote: post #8
chton wrote: post #5

Earlier quoted context omitted.

That's a possibility, but the special fuel they have would have to have been extremely expensive then. That would have been a fine explanation, and if they had mentioned it in the movie that would be one less point I could make. But here's another one: They set up this nice system with pings to know what planets might be suitable, but they can't detect when a ping is being repeated instead of actually sent by a perso…

But they could. That is exactly why they did know about nice atmosphere and water on the planet, but didn't know about the waves since the first wave that killed first astronaut happened during the landing. They also left one of the team member to do gravitation research and planned to spend as little time as possible on the planet.

Yes, they knew about the relativistic effects. And they could obviously send some data. But somehow they can't figure out that they've been getting a repeat of the same ping for the last 10 years? And even if they couldn't figure that out, how could the person on the planet possibly send a ping every year, if she only spent an hour and half on it according to her frame of reference?

Re: Kip Thorne: The science of Interstellar

#14

Post by vacri »

harshreality wrote: post #10
chton wrote: post #2

Surely Kip Thorne himself has to realize that he's grasping at straws. A lot of the things he mentions are of the type "in this precise, extremely rare situation it is possible, if we ignore all the other side effects". For example, I'm sure his calculations will be correct regarding the planet orbiting a black hole close enough for relativistic effects. What it also means is that the planet would pass through the ex…

I couldn't agree more. I don't understand why Kip Thorne is so desperate to declare that the movie doesn't violate known physics, when it clearly does, just not in the areas he's most concerned with. Planetary dynamics, propulsion systems... but as long as there aren't Na'vi or dragons on the planets, I suppose they consider it realistic enough. On second thought, Na'vi or dragons might be more realistic than some of…

The point of the time dilation is 'plot'. It's to age the daughter to a point where she's now a prominent scientist and can interpret the main character's weird sendings, while not being dismissed as a weird kid.

In terms of the literal events of the film, it's the last planet they should have visited, given the urgency they have to find a place for the people back home - a few months round trip to come back and check it is only a few months back home, but a couple of hours at the known 'time dilation' is decades back home. Doesn't make internal sense... except for 'plot'.

Re: Kip Thorne: The science of Interstellar

#15

Post by gglon »

chton wrote: post #13
gglon wrote: post #8

Earlier quoted context omitted.

But they could. That is exactly why they did know about nice atmosphere and water on the planet, but didn't know about the waves since the first wave that killed first astronaut happened during the landing. They also left one of the team member to do gravitation research and planned to spend as little time as possible on the planet.

Yes, they knew about the relativistic effects. And they could obviously send some data. But somehow they can't figure out that they've been getting a repeat of the same ping for the last 10 years? And even if they couldn't figure that out, how could the person on the planet possibly send a ping every year, if she only spent an hour and half on it according to her frame of reference?

I don't remember how many pings they received in the movie. I've understood that they had received just one ping from that planet.

Re: Kip Thorne: The science of Interstellar

#16

Post by harshreality »

vacri wrote: post #14
harshreality wrote: post #10

Earlier quoted context omitted.

I couldn't agree more. I don't understand why Kip Thorne is so desperate to declare that the movie doesn't violate known physics, when it clearly does, just not in the areas he's most concerned with. Planetary dynamics, propulsion systems... but as long as there aren't Na'vi or dragons on the planets, I suppose they consider it realistic enough. On second thought, Na'vi or dragons might be more realistic than some of…

The point of the time dilation is 'plot'. It's to age the daughter to a point where she's now a prominent scientist and can interpret the main character's weird sendings, while not being dismissed as a weird kid. In terms of the literal events of the film, it's the last planet they should have visited, given the urgency they have to find a place for the people back home - a few months round trip to come back and chec…

I understand that time dilation was necessary for the plot. They should have found another way to age the crew, though, that didn't violate common sense.

The crew knew about the time dilation before deciding to try that first planet. They should have realized the data they were getting was only about an hour old. Didn't they say something about not getting any communication from the scientist, just automated transmission of probe data? Only an hour's worth of data and no communication from the scientist should have easily put that planet in the last resort category.

Re: Kip Thorne: The science of Interstellar

#17

Post by ThePhysicist »

Accuracy aside, from a scientific point of view Interstellar was one of the most interesting movies in a long time, and it really made me think about Physics a lot again.

It's really cool to see how much you can actually learn about the universe of Interstellar by making use of some Physics knowledge and the information given to you in the movie.

An example: The first planet they visit orbits Gargantua (the supermassive black hole mentioned in the movie - https://en.wikipedia.org/wiki/Supermassive_black_hole) at a distance very close to its Schwarzschild radius (or event horizon). In the movie, they say that the time dilation there is such that one hour passed at the surface of the planet corresponds to 7 years (!) on Earth. Interestingly, with that information alone we are already able to calculate how close the planet is to the Schwarzschild radius of the black hole by using a really simple formula: https://en.wikipedia.org/wiki/Schwarzschild_radius (here we have to assume that the black hole is not rotating very fast).

Making some assumptions about the mass of the black hole then allows us to see how large the actual Schwarzschild radius is in fact, and if the time dilation shown in the movie is possible (it is). Similarly, if we use the information they give us about the gravity constant on the planet (about 1.3 times Earth gravity if I remember correctly) as well as an estimate of the height of the tidal waves they find there (maybe 200 meters?), we could even estimate the rotation period of the planet.

There are many more examples of clues like this in the movie, which offer great 'Fermi problems' (https://en.wikipedia.org/wiki/Fermi_problem) and allow us to learn many things about the universe presented to us in Interstellar.

Of course I also have to mention the absolutely stunning rendering of the black hole, which incorporated the gravitational lensing effects (https://en.wikipedia.org/wiki/Gravitational_lens) that make the accretion disk of the black hole appear like a halo surrounding it. Also, the rendering of the wormhole as a four-dimensional "hole" embedded in three-dimensional space was absolutely gorgeous.

Amazing movie, amazing science, amazing universe.

Re: Kip Thorne: The science of Interstellar

#18

Post by harshreality »

dijxtra wrote: post #9
chton wrote: post #5

Earlier quoted context omitted.

That's a possibility, but the special fuel they have would have to have been extremely expensive then. That would have been a fine explanation, and if they had mentioned it in the movie that would be one less point I could make. But here's another one: They set up this nice system with pings to know what planets might be suitable, but they can't detect when a ping is being repeated instead of actually sent by a perso…

The biggest issue I see is the fact that gravitational time dilation is considerable on the surface of the Miller's planet, but not so much in the relatively close proximity of the planet, where the mothership is. I just don't get that part.

The explanation Kip Thorne offers in his book is that the lander ends up slingshotting around two things, like black holes and neutron stars, that happen to be in the right places to drop the lander into the gravity well and then accelerate it back into a stable orbit close to the planet. Of course, that kind of maneuver twice, on both the descent into Gargantua's gravity well and the return trip, is totally implausible... the idea that there are so many high gravitation objects orbiting Gargantua near the planet's orbit that you can pull it off on no particular schedule... but it might not be physically impossible.

Wouldn't that be yet another reason to avoid that planet like the plague? Even if they set up a colony there, at any time the planet could run into an orbiting black hole or neutron star, or get slingshotted by one of them into an unfavorable orbit or into Gargantua itself.

Re: Kip Thorne: The science of Interstellar

#19

Post by hessenwolf »

vacri wrote: post #12
chton wrote: post #2

Surely Kip Thorne himself has to realize that he's grasping at straws. A lot of the things he mentions are of the type "in this precise, extremely rare situation it is possible, if we ignore all the other side effects". For example, I'm sure his calculations will be correct regarding the planet orbiting a black hole close enough for relativistic effects. What it also means is that the planet would pass through the ex…

I liked Intersteller a lot as well, but its plot was horribly contrived in places and the science isn't as good as it was purported to be - even moreso if you include the behaviour of the scientists involved :). The science was certainly better than most other serious sci-fi films though. The real problem with the film is the needlessly long hour of character establishment. (SPOILER) Rather interestingly, I've seen v…

My wife, ordinarily interested in more economic, financial, and fashion-related literature, has been gorging on tesseracts since the movie. She'll adore this. Thank you for the brownie points.

Re: Kip Thorne: The science of Interstellar

#20

Post by dr_zoidberg »

ThePhysicist wrote: post #17

Accuracy aside, from a scientific point of view Interstellar was one of the most interesting movies in a long time, and it really made me think about Physics a lot again. It's really cool to see how much you can actually learn about the universe of Interstellar by making use of some Physics knowledge and the information given to you in the movie. An example: The first planet they visit orbits Gargantua (the supermass…

I haven't checked the numbers in any way, but is it safe to assume that the black hole is not rotating "very fast"? In the news covering the render software and papers that will be/have been published, it was mentioned that they were surprised to see the effect the rotation of the black hole has on the accretion disk -- that it bends and twists space and light, so insted of a flat, Saturn-ring-lik disk, you end up with the thing you see in screen.
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