Can anyone explain Interstellar Questions?

  • #1
1.Coop lands on coop station at saturn, but why he returned to saturn instead of earth?
2.how Murph is at coop station at saturn, but murph actually stays on earth, but how she present on coop station which is at saturn?
3. how coop send Morse code through wrist watch just by clicking back side of library books, & also what is the use of sending Morse code?
 

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  • #2
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The ending was rather confusing. I think humanity figured out how to escape the earth. Murph had solved Dr Brands problem and thus created an ark to escape to Saturn and the next stop would be to send people through the wormhole to a new world.

In the beginning of the movie, Murph tells her Dad that someone is communicating with her telling to stop her Dad from going. In the end, we find Coop trying to send that message by pushing out the books because he wished he never left her behind. Then he realizes he can save her so he sends the data on what it's like inside a black hole by morse code that she can then use to complete Dr Brands work.

There's a good book by Kip Thorne called The Science of Interstellar that goes into some of the science and speculative ideas that shaped the movie and why the director did what he did for the story to flow.
 
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  • #3
why the houses at coop station on saturn are in the shape of "O'Neill cylinder"?
 
  • #5
Drakkith
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1.Coop lands on coop station at saturn, but why he returned to saturn instead of earth?
2.how Murph is at coop station at saturn, but murph actually stays on earth, but how she present on coop station which is at saturn?
3. how coop send Morse code through wrist watch just by clicking back side of library books, & also what is the use of sending Morse code?

1. Because there's a space station at Saturn. The return trip to Earth would take something like 2 years. Better to pick him up and treat him at the space station.
2. Murph doesn't stay on Earth. She goes to Saturn. The end of the film is about 80-100 years after Coop first left Earth, and about 40-60 years after Murph gets the Morse code message from Coop while on Earth.
3. The film doesn't show it very well, but Coop is directly manipulating the watch's second hand. If I remember correctly, you can see a slight "blur" going from the watch up to Coop's hand, showing that he's manipulating it. He's using Morse code to send the data gathered on the black hole to her, allowing her to develop a quantum theory of gravity, which apparently is what is needed to save Earth. (Can't remember why exactly)
 
  • #6
DaveC426913
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...develop a quantum theory of gravity, which apparently is what is needed to save Earth. (Can't remember why exactly)
It allowed them to lift whole populations and industries into space where they could rebuild Humankind without the threat of the plague that consumed Earth. The NASA base on Earth was actually an entire space habitat ready to be lifted into orbit and populated - if they could solve the gravity problem.
 
  • #7
Drakkith
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It allowed them to lift whole populations and industries into space where they could rebuild Humankind without the threat of the plague that consumed Earth. The NASA base on Earth was actually an entire space habitat ready to be lifted into orbit and populated - if they could solve the gravity problem.

Ah yes, now I remember Coop looking at the place sideways.
 
  • #8
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1.Coop lands on coop station at saturn, but why he returned to saturn instead of earth?

The wormhole to the Gargantua system has a mouth near Saturn.

2.how Murph is at coop station at saturn, but murph actually stays on earth, but how she present on coop station which is at saturn?

By spaceship, and presumably one a lot faster than the rocket ship Cooper took.

3. how coop send Morse code through wrist watch just by clicking back side of library books, & also what is the use of sending Morse code?

Through a gravitational signal transmitted backwards in time.
 
  • #9
Drakkith
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Through a gravitational signal transmitted backwards in time.

I don't think that's what happened. From what I remember, Coop was in some sort of 5th dimension where he could move to different points in time. No signal was transmitted backwards in time because he was really present at that point in time.
 
  • #10
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I don't think that's what happened. From what I remember, Coop was in some sort of 5th dimension where he could move to different points in time. No signal was transmitted backwards in time because he was really present at that point in time.
That's not the idea. Just making the universe 5 dimensional doesn't let you to be able to travel to different times that easily. For doing that, you need to be in a manifold in which our universe is embedded in. Something like seeing a 2 dimensional surface in 3 dimensions. But I can't remember a theory suggesting our universe is embedded in a higher dimensional manifold. Although this can't be an objection to the film but is in contrast with their insistence on getting all the ideas in the film from physics. Or maybe there is such a theory and I've never heard of it!
EDIT:Isn't it Tegmark's multiverse?
 
  • #11
Drakkith
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I don't know where exactly they got their ideas from, but I remember them talking about the 5th dimension and about using it to move along the timeline.
 
  • #12
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I don't think that's what happened. From what I remember, Coop was in some sort of 5th dimension where he could move to different points in time. No signal was transmitted backwards in time because he was really present at that point in time.

Coop wasn't "in a 5th dimension." He was in a device that permitted him to perceive light from certain events in the past and transmit gravitational signals with amplitude in a 4th spatial dimension (along a path that would intersect approximately with the light-transmitting event). This is described in Chapter 30 of Kip Thorne's book.
 
  • #13
Drakkith
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Coop wasn't "in a 5th dimension." He was in a device that permitted him to perceive light from certain events in the past and transmit gravitational signals with amplitude in a 4th spatial dimension (along a path that would intersect approximately with the light-transmitting event). This is described in Chapter 30 of Kip Thorne's book.

Okay. But was this in the movie?
 
  • #14
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Okay. But was this in the movie?

Yes. In fact, aside from the depiction of Gargantua, I thought the depiction of the tesseract device and its operation was one of the more pleasant surprises.
 
  • #15
Drakkith
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Yes. In fact, aside from the depiction of Gargantua, I thought the depiction of the tesseract device and its operation was one of the more pleasant surprises.

I mean was the explanation you gave also the one given in the movie. I only saw it once and can't remember all the details.
 
  • #16
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I mean was the explanation you gave also the one given in the movie. I only saw it once and can't remember all the details.

There's no dialogue or obvious signage explaining what's depicted, as I recall.
 
  • #17
Drakkith
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There's no dialogue or obvious signage explaining what's depicted, as I recall.

Ah okay. No wonder what you said wasn't matching up with what I remembered. Although I think I remember Coop talking about someone constructing it for them. I assumed that he was *in* the 5th dimension, but I guess that's just silly!
 
  • #18
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Ah okay. No wonder what you said wasn't matching up with what I remembered. Although I think I remember Coop talking about someone constructing it for them. I assumed that he was *in* the 5th dimension, but I guess that's just silly!

The key point is that the depiction is consistent with what Kip Thorne described, and according to Thorne that is precisely what Nolan intended.
 
  • #19
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I have watched it.
Start with the bad things, there are a number of them, so i understand those who disliked the movie.

They could construct an artificial biosphere in space, werent building domed cities on Earth enough to save humanity?
My knowledge is limited, but IMHO manuevering in the gravity well of a black hole requires hell of delta-V, that would have been enough to evacuate millions of people from Earth.
Why couldnt they stretch that wormhole to Earth, simply connect it with another life support planet?
Ok fall inside the event horizont sounds really mystical, but making tons of experiments in a wormhole is the second best thing... but they havent even mentioned it.
Why were they so ready to believe that the ice planet without breathable atmosphere will be just fine for a colony? Then a Mars colony would have been also enough.
I think Anna's speech about love as a physical force... was a bit overforced.

On the other hand, it was a really well written film with good points and scenes, i have enjoyed it, i could suggest it anyone with a certain amount of suspension of disbelief. :)
 
  • #20
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They could construct an artificial biosphere in space, werent building domed cities on Earth enough to save humanity?

Several possibilities, ranging from "terrestrial agriculture is too far gone" to "man beats blight, starts farming in space to better hedge his bets."

My knowledge is limited, but IMHO manuevering in the gravity well of a black hole requires hell of delta-V, that would have been enough to evacuate millions of people from Earth.

Science of Interstellar proposes that Endurance used gravitational slingshots to plod around the Gargantua system. Thorne proposes a system of at least 5 intermediate mass black holes in the book. Cooper makes an off hand reference swing off a neutron start in the movie. Reconciling the two or coming up with more consistent explanations is left as an exercise to the viewer.

Why couldnt they stretch that wormhole to Earth, simply connect it with another life support planet?

Presumably because they lacked the know how and means to do so.

Ok fall inside the event horizont sounds really mystical, but making tons of experiments in a wormhole is the second best thing... but they havent even mentioned it..

Perhaps they did, and didn't discover the missing piece of the MacGuffin in the attempt.

Why were they so ready to believe that the ice planet without breathable atmosphere will be just fine for a colony? Then a Mars colony would have been also enough.

Several reasons non-exclusive reasons, including but not limited to:
1. Mann lied, so they had no idea. Nor would they without approaching the world in the first place (due to time dilation).
2. Planetary chauvenism. We have experience with this today with all the Marshot lunacy. Fortunately, by the end of the movie, Americans at least have expanded their horizons a bit.

I think Anna's speech about love as a physical force... was a bit overforced.

I thought it was beautifully shot down by Cooper, with the icing on the cake being that final shot of Anna stranded and alone over a grave while the rest of mankind enjoys luxury digs in massive space habitats.

On the other hand, it was a really well written film with good points and scenes, i have enjoyed it, i could suggest it anyone with a certain amount of suspension of disbelief. :)

For a more enjoyable experience, don't suspend disbelief. Take it as a challenge to square the film with what we know to be plausible. That's my take, at least.
 
  • #21
Drakkith
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For a more enjoyable experience, don't suspend disbelief.

How's that make it more enjoyable?
 
  • #22
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How's that make it more enjoyable?

Because it's an educational film. Hell, even working astrophysicists might learn a thing or two once Thorne and Double Negative deliver on their promised publications.
 
  • #23
Drakkith
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Because it's an educational film.

You and I have different ideas of what an educational film is! ;)
 
  • #24
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You and I have different ideas of what an educational film is! ;)

Have you seen what gets on The Science Channel these days? ;)

In all seriousness, though, how does Interstellar differ substantially from an episode of Cosmos or Through the Wormhole? Longer. No narrator. But plenty of material with very few (probably fewer) warts to pick apart. Certainly enough that Kip Thorne managed to pump out a few hundred pages worth of explanation for why nearly everything is as grounded as it gets.
 
  • #25
Drakkith
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Interstellar's primary goal is to entertain people with a story. To me and educational film/show's primary purpose is to entertain people with new knowledge. There will be overlap between the two of course.
 
  • #26
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Interstellar's primary goal is to entertain people with a story. To me and educational film/show's primary purpose is to entertain people with new knowledge. There will be overlap between the two of course.

I'm less concerned with intent than the result, and in this case the sausage makers did a great job.
 
  • #27
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Have you seen what gets on The Science Channel these days? ;)

In all seriousness, though, how does Interstellar differ substantially from an episode of Cosmos or Through the Wormhole? Longer. No narrator. But plenty of material with very few (probably fewer) warts to pick apart. Certainly enough that Kip Thorne managed to pump out a few hundred pages worth of explanation for why nearly everything is as grounded as it gets.
The answer is known accepted science for cosmos, not sure how much of through the wormhole is, Interstelar, very little in the movie, despite what Kipthorn wanted.
 
  • #28
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The answer is known accepted science for cosmos, not sure how much of through the wormhole is, Interstelar, very little in the movie, despite what Kipthorn wanted.

Kip Thorne disagrees.

Kip Thorne said:
But most important to me was our vision for a blockbuster movie grounded from the outset in real science...Nine years later, Interstellar is achieving all we envisioned.

After seeing the movie, reading the companion book, and discussing it here and elsewhere, I have to agree with him.
 
  • #29
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2. Planetary chauvenism. We have experience with this today with all the Marshot lunacy. Fortunately, by the end of the movie, Americans at least have expanded their horizons a bit.

Maybe we could discuss it in another topic, especially if there is no return to Earth, i see no advantage of a space tin can compared to a domed city, even if the planet has lower gravity.

Why did they land on the slow time planet anyway? Didnt they expect so strong tidal forces so close to the black hole? Even if they didnt, they could have seen those huge waves with a probe.
 
  • #30
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Maybe we could discuss it in another topic...

I think the mods would like to limit the growth of Interstellar-related threads, but I don't mind discussing it here.

Especially if there is no return to Earth, i see no advantage of a space tin can compared to a domed city, even if the planet has lower gravity.

Energy. Settling the freefall environment opens up far more efficient modes of living than you get on the surface of a large. You can distribute climate, biomes, people and infrastructure across as many nodes as you choose to build. You can access freefall and move mountain sized rocks great distances for a fraction of the cost required to make orbit from the surface of a planet. If you want gravity, you can spin a rock and settle the interior--and getting to space is as easy as climbing a hill or drilling a hole.

Basically, if you spend so much energy trying to get off the surface of one rock, why would you want to expend even more dropping back down if you could avoid it? The answer? Planetary chauvinism. It may be best to avoid planets, but that doesn't mean the people with budget authority will tumble towards the most optimal path. After all, NASA and the general public are still fond of this whole Marshot business.

Why did they land on the slow time planet anyway? Didnt they expect so strong tidal forces so close to the black hole? Even if they didnt, they could have seen those huge waves with a probe.

They landed because they got reports saying the planet was viable. The massive Lorentz factor on Miller's planet is precisely the reason why they 1) couldn't observe the waves from a distance and 2) probe comprehensively before attempting manned landing. The Endurance crew makes a big ado about being on the clock--relative to Earth--and needing to minimize time deciding whether Miller's Planet was a go or no go. Since 1 hour on Miller's planet is 7 years to a distant observer, those waves might as well have been standing still from afar. And since Cooper wanted to be in and out within 10 years Endurance time, time constraints might not have given crew enough leeway to do a comprehensive oceanographic and geophysical survey from orbit. Unfortunately, a perfect storm of ostensibly reasonable decisions and confounding unknowns resulted in disaster--the loss of a crew member and 23 years in total.
 
  • #31
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"Since 1 hour on Miller's planet is 7 years to a distant observer, those waves might as well have been standing still from afar."

In the vicinity of a black hole, very strong tidal forces can be expected, Jupiter isnt a black hole, but it generates very strong tidal effects on Io.

2. https://www.physicsforums.com/threads/survival-on-mars.765443/
My topic about Mars colonization, maybe we can continue there the planetary thing.
My last answer here (i think not entirely OFF, as it was also a question in the movie, whether we should search for a quite Earth like planet, or build space stations) : spin up the colony to mimic gravity also requires lots of propellant, aerobreak can help landing on Mars, once you landed a proper colony seed, you can access lots of useful materials even on foot (thanks to gravity, thick layer of dirt is enough for radiation protection for example), and have a whole planet to expand the colony, a railway enough to transport between them.
I admit the return to Earth part is harder, but in the movie, they didnt want to return.
 
  • #32
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"Since 1 hour on Miller's planet is 7 years to a distant observer, those waves might as well have been standing still from afar."

In the vicinity of a black hole, very strong tidal forces can be expected, Jupiter isnt a black hole, but it generates very strong tidal effects on Io.

Tidal force depends on the gradient of the field. Kip Thorne worked out Gargantua's characteristics based on the plot's necessities, one of which was that Miller's planet has to be exceptionally close without being torn apart by tidal forces. Hence, a black hole at least 100 million times more massive than the sun and circumference comparable to the that of Earth's orbit around the sun.

2. https://www.physicsforums.com/threads/survival-on-mars.765443/
My topic about Mars colonization, maybe we can continue there the planetary thing.

I'll check it out.

My last answer here (i think not entirely OFF, as it was also a question in the movie, whether we should search for a quite Earth like planet, or build space stations) : spin up the colony to mimic gravity also requires lots of propellant

Solar system's full of comets. Saturn especially has a lot of ice-water in her rings.

aerobreak can help landing on Mars

For certain interplanetary trajectories. Not terribly helpful for Mars orbital paths. And also you still have the problem of getting people and stuff off Mars. These are problems you don't have with the enormous amount of weakly gravitating rubble falling all over the place in our solar system.

once you landed a proper colony seed, you can access lots of useful materials even on foot (thanks to gravity, thick layer of dirt is enough for radiation protection for example), and have a whole planet to expand the colony, a railway enough to transport between them.

You have lots of materials in asteroids, on lightly gravitating moons and planetoids, in comets, and in Saturn's rings. And you have the whole of empty space in which to expand.

I admit the return to Earth part is harder, but in the movie, they didnt want to return.

But they might want to get to other destinations in space.
 
  • #33
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Continuing discussion of planetary chauvinism and Marshots here.
 

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