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Kip Thorne: The science of Interstellar

blogs.scientificamerican.com

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Re: Kip Thorne: The science of Interstellar

#91

Post by patrickk »

tambourine_man wrote: post #48

spoilers I liked the film, and it bothers me a bit that they can launch from a planet with stronger gravity using tiny rockets, or that we would consider a planet orbiting the event horizon of a huge black hole as good candidate for our new home. But my biggest gripe is with the premisse of the film. We have a catastrophic ecological disaster, which is unconvincingly explained in a single sentence by Michael Caine, a…

Or the idea of abandoning Earth because it's too hostile to grow crops with some dust storms, yet the idea of colonising a distant, extremely harsh-for-human-life planet is a more realistic idea. Surely building massive "vertical farms" or other artificial environments here on Earth would be more cost effective and realistic.

Overall I think we may be thinking too deeply about the plot ;-)

Re: Kip Thorne: The science of Interstellar

#92

Post by debacle »

timdiggerm wrote: post #90
arikrak wrote: post #89

It sounds like he's just discussing certain aspects of the film, while ignoring much more glaring issues. It's not ice clouds that are the issue, it's the entire story. [Spoiler alert] Here's the whole plot of the movie, does any aspect of it make sense? Earth is dusty so the simplest solution is to transport all of humanity through a wormhole to another planet. The main characters go through a wormhole and walk arou…

>he ends up in a multi-dimensional space where he sends Morse code messages to his daughter in the past by moving her books and watch. How does he do that? Because the multi-dimensional space was set up by higher-dimensional creatures, who also created the wormhole, specifically so he could accomplish all this (right down to preventing him from going on the earlier missions by causing his craft to crash with a gravit…

That seems like a rather roundabout way to save the human race, no? A love-powered hyper-dimensional gateway used to transmit Morse code sounds like something straight out of h2g2.

Re: Kip Thorne: The science of Interstellar

#93

Post by seanflyon »

snowballsteve wrote: post #62
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…

The wormhole was perfect, except the travel bit bugged me. They use the 2d analog with paper. The second you pass through the hole in one location you emerge from the hole in the other location. In the third dimension, as they touch the sphere near Saturn they would be leaving the surface of the sphere on the other side. From their point of view they should be about to hit the 'ball' then all of a suddenly then are t…

Imagine in the 2D analog, if there was a small gap of air between the 2 points on the paper.

Re: Kip Thorne: The science of Interstellar

#94

Post by magicalist »

nsxwolf wrote: post #73

Why was the Ranger launched from Earth on a giant rocket, but was single stage to orbit on all the other Earth-like worlds? The only thing I've been able to think of was that they used some kind of exotic propulsion, like antimatter, therefore there was no sense wasting such a precious commodity to leave Earth if you had a rocket available. But nothing in the movie seemed to explain it.

There is the one-off about this being the last of its kind space vehicle, and the booster pack in orbit had been there for quite some time. You can somewhat fanwank that into meaning they had to use older, simpler technology to get the capsule itself into orbit, but then could take advantage of the pre-Blight technology already in orbit for the rest of the movie. That's about the same as your explanation, though.

Pretty weak, so it would be nice if they had at least given us a throwaway sentence or two to wave it away like they did with spaghettification, as the rocket orbital mechanics, at least, were distracting. I imagine the real reason was Nolan wanted to invoke a parallel to the Apollo missions in the liftoff from earth, but didn't want to waste time with the very hard problem of getting off other worlds once you get there.

Re: Kip Thorne: The science of Interstellar

#95

Post by delinka »

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…

"in this precise, extremely rare situation it is possible, if we ignore all the other side effects"

Isn't that storytelling? The impossibly ridiculous plot works only when all the pieces fall exactly as the author wants. Depending on your point of view, all the circumstances that brought intelligent beings into existence on our planet are themselves an extremely rare situation.

Re: Kip Thorne: The science of Interstellar

#96

Post by mcguire »

stillsut wrote: post #86

What was the deal with "the blight"? At one point, they mentioned it had to do with the ability to fix nitrogen? Also, wouldn't any pestilence as widespread as that be transported on the cargo ships with the people and their plants to the new planet?

In hard science fiction, "science" is physics. Maybe chemistry, maybe. But biology is all squishy and such and doesn't carry the mathematical gravitas needed to be taken seriously.

Re: Kip Thorne: The science of Interstellar

#97

Post by mcguire »

m_mueller wrote: post #80
koepked wrote: post #56

Earlier quoted context omitted.

Even with a ship capable of overcoming the gravity wells present in the movie, it would likely still make sense to launch from Earth with boosters/staging to increase the amount of fuel/energy available to the ship for the rest of the journey.

Yes, that's a valid argument I think. On the other hand, I'd imagine if our technological level is such that we have SSTO ships (with SSTO even for more massive gravity wells than Earth's), we'd probably not use rockets but have another SSTO tanker fueling up the ship in orbit. You could maybe argue that ressource constraints in their dire situation have forged a situation where they put everything they had into thos…

A rocket-scientist (ok, aerospace engineer by training) friend was recently surprised that he hadn't realized this:

"If the radius of our planet were larger, there could be a point at which an Earth escaping rocket could not be built. Let us assume that building a rocket at 96% propellant (4% rocket), currently the limit for just the Shuttle External Tank, is the practical limit for launch vehicle engineering. Let us also choose hydrogen-oxygen, the most energetic chemical propellant known and currently capable of use in a human rated rocket engine. By plugging these numbers into the rocket equation, we can transform the calculated escape velocity into its equivalent planetary radius. That radius would be about 9680 kilometers (Earth is 6670 km). If our planet was 50% larger in diameter, we would not be able to venture into space, at least using rockets for transport."[1]

[1] http://www.nasa.gov/mission_pages/station/expeditions/expedi...

Re: Kip Thorne: The science of Interstellar

#98

Post by hansjorg »

Tycho wrote: post #30

Does he explain the glaring paradox of the time travel storyline? Someone said it is permissible as a 'closed timelike curve' but smells like BS to me.

One resolution I've seen mentioned is that if Brand succeeded with Plan B then maybe "they" are the ancestors of the Edmunds-planet. That would resolve the paradox at least.

Re: Kip Thorne: The science of Interstellar

#99

Post by magicalist »

debacle wrote: post #92
timdiggerm wrote: post #90

Earlier quoted context omitted.

>he ends up in a multi-dimensional space where he sends Morse code messages to his daughter in the past by moving her books and watch. How does he do that? Because the multi-dimensional space was set up by higher-dimensional creatures, who also created the wormhole, specifically so he could accomplish all this (right down to preventing him from going on the earlier missions by causing his craft to crash with a gravit…

That seems like a rather roundabout way to save the human race, no? A love-powered hyper-dimensional gateway used to transmit Morse code sounds like something straight out of h2g2.

(spoilers, obviously) It's a predestination paradox -- so, as with all predestination paradoxes in fiction, the story is a little too in love with the use of it -- but the movie sets the ground rule that the only way to communicate backwards is to manipulate gravity, therefore that's how they're going to have to accomplish it.

As for the love-powered part, everyone's a little too hung up on that set of dialog. There's nothing in the plot that relies on it. Sufficiently advanced magic gravity technology is more than enough. Is any advancement of the plot motivated by more than the fact that he wants to see his daughter again? Sure, if they had listened to Brand's feelings they wouldn't have ended up with crazy guy and would have ended up on a (seemingly) habitable planet, but the human race also would have died on earth and lived on entirely from the test tube embryos.

The whole tesseract section doesn't entirely fit with the tone of the rest of the movie but it's not powered by love.

Re: Kip Thorne: The science of Interstellar

#100

Post by debacle »

magicalist wrote: post #99
debacle wrote: post #92

Earlier quoted context omitted.

That seems like a rather roundabout way to save the human race, no? A love-powered hyper-dimensional gateway used to transmit Morse code sounds like something straight out of h2g2.

(spoilers, obviously) It's a predestination paradox -- so, as with all predestination paradoxes in fiction, the story is a little too in love with the use of it -- but the movie sets the ground rule that the only way to communicate backwards is to manipulate gravity, therefore that's how they're going to have to accomplish it. As for the love-powered part, everyone's a little too hung up on that set of dialog. There'…

Why not prevent the whole mess by just sending a clear message in Morse to almost anyone at NASA from the future using gravitational waves?
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