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Physicist Kip Thorne On the Physics of "Interstellar"
A review of Interstellar at Scientific American that was not entirely flattering of the film's scientific aspects caught the eye of Cal Tech physicist Kip Thorne, who served as a consultant on the movie, and has actually written a book on the physics depicted. He and SciAm writer Lee Billings ended up having a conversation about how the film deals with time travel, black holes, and more. A slice:
I think the laws of physics very probably forbid warp drives and traversable wormholes. The research that has gone on over the past 25 years trying to determine whether its possible all point in negative directions, but it’s not a firmly closed door. So there are two issues here. One is that the laws of physics probably forbid it, but, gee, if they don’t, it would be great to have! The other is that the technology required to make a warp drive or a traversable wormhole is so far, far, far beyond the technology needed for a laser sail or a nuclear-pulse rocket that I would not be in favor of putting any significant resources into trying to develop it.
Now, you may have small amounts of money—tens or hundreds of thousands of dollars—spent on this, but nothing is wrong with that. Peer-review, at least in the United States and in Europe, is too strong for there to be any danger of millions or billions of dollars being spent on these things. The technology required for wormholes is so far removed from our current and plausible near-future capabilities that to throw lots of money at it would almost certainly be a total boondoggle.
Tidal forces. This is the biggy, If you are in orbit deep in a gravity well with a steep gradient then the orbital velocities of things 1m up/down from each other are significantly different. The material stength of any object extending over that 1m has to resist that force.
Those forces will rip materials to shreds.
Think of your hands being pulled up, while your feet are pulled down. The further into the gravity well you get the more up and the more down the two pulls get.
The only way to avoid the tidal forces are a straight in drop. But you can't do that as all around the well is a swirling gas field that will push you into an orbit.
Does that cover the government projects where they bail to private companies that are to big to fail?
Yes. They should have let them fail, but then they wouldn't have gotten the golden parachutes.
Taking guns away from the 99% gives the 1% 100% of the power.
Spoiler alert for the movie Interstellar
It seems he did not get the main idea of the movie. The whole movie rests on the idea that it is possible to manipulate gravity in the past. The traversable wormhole was created by some humans in the far future and allowed the main character to communicate with the past, causing himself to join a space program, which would lead him to the place to communicate with the past, and by this save human kind from some disaster and in the far future allow to develop the technology to create the wormhole and a black hole with strange properties. So, it also involves a form of bootstrapping. Which makes even less sense, if indead traversable wormholes could be made at all.
Yeah, the blog post seems a little insane to me. I get it when Neil deGrasse Tyson complains about things like, in some movie the Earth spins the wrong way, or if the constellations are wrong for the time that the movie takes place. He's nit-picking and he knows it. He's pointing out interesting scientific inconsistencies. It might possibly be educational, and he's showing off his knowledge and attention to detail, and whatever, that's fine.
But this guy is actually complaining that the movie depicts a stable wormhole that we can travel through. His problem with it is, scientifically, we have no reason to think that it's possible, though we don't strictly know. Did he think that either Christopher Nolan or the audience was not aware that we can't create wormholes?
Even in the movie, it's not depicted as something that's easy to create. But that's beside the point, really, since it's a science fiction movie that is just positing that such a thing is possible for the sake of building a plot around that supposition. It's like complaining about Jurassic Park on the grounds that, "It's unlikely that we'll ever be able to clone dinosaurs from ancient mosquitoes formed in amber." Or complaining about the movie E.T. because, "We've never been visited by extra-terrestrial life forms-- at least not so far, not as far as we know..."
No, 50 years ago the primary limitations blocking cell phones were in the engineering, not so much in the theoretical physics.
You will have to reach back a few hundred years before cell phones were a theoretical impossibility.
Which means, unless you expect to live another several hundred years, there is no way you will see warp drive in your lifetime.
I see so many people going on about who great this film was but I can't help but wonder what it was that I missed?
The film is about Love. Everything else is window dressing.
If you try and make the film to be about something else, you will be disappointed.
I like microcars
The mortgages themselves weren't the problem. The problem was the inflation of the mortgages into many times their original value, using financial derivatives and insurance. Because the derivatives were rated AAA, shadow banks didn't take out enough insurance. And insurance companies didn't really insure the derivatives, because they were rated so high they couldn't fail.
Then a few RMBSes failed, and market groupthink took over. Suddenly no one wanted these derivatives, not because they had no value, but because the market became paranoid and emotionally panicked. No private party wanted to roll over funding using the derivatives as collateral anymore. The private parties all wanted T-bills, because they were much much safer.
The government stepped in to take the instruments off the banks' balance sheets.
The government didn't make banks create financial derivatives. The government didn't rate those derivatives AAA. The government didn't fail to insure them adequately. In fact, the government became the insurer when the ostensible insurers (i.e., AIG) failed.
Righties like to quote Kenneth Rogoff. Here's a quote from him:
Why don't righties quote that passage from Rogoff? Why wasn't bailing out individuals politically feasible? Because of the ignorance of the Tea Party, that's why.
Actually the whole point is that we have several theoretical constructs that should allow travel from A to B at speeds greater than lightspeed. All rely on the fact that special relativity only imposes a local speed limit: i.e. you can't travel faster than light *through space*. Nothing in it forbids the existence of short cuts (wormholes) that connect distant parts of the universe with drastically shorter paths. Nor does it forbid things like an Alcubierre warp drive, where you don't move at all through the space you're in, but instead move an isolated bubble of flat space through the surrounding space at arbitrary speeds, while leaving the contents of that bubble of space in free fall (Relativity imposes no speed limit on space itself.)
Both constructs have their weak spots, but so far every time someone comes up with something showing them to be "impossible" somoeone else comes up with a modified construct that removes the impossibility. And of course there's the little issue that if Special Relativity is correct then any method of getting between A and B faster than light can also be used to send information into your own past, which would wreak havoc with our understanding of causality. But then the whole "time passes in only one direction" thing is a serious weak spot in our current understanding of the universe as well, so it may be that it's only us that would have an objection to causality loops, and not the universe itself.
Where every construct falls flat on it's face is that we have absolutely no idea how to actually create such a thing - we're mathematically modeling the things we might be able to do if we had nuclear reactors while still living in the stone age. But then that's what our species does, we tell ourselves stories of things that have never existed, and then try to figure out how to make them exist. We did it when our ancestors imagined how useful a killing-stone with a long, light handle would be, and we do it today on a million different fronts. Only difference is today we do our imaginings with a level of mathematical precision that guarantees that, if our starting assumptions are true, then the thing we imagine can in principle be built, even if we don't know how to do so at present.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
*Warming: (mild) spoilers follow*
They leave Earth with a Saturn V like rocket and they take 2 years to go to Saturn. That contrasts Cassini's and Pioneer 11's 6.5 years to get there and the 3 years for the two Voyager probes. Let's say that 2 years is within the bounds of what we could achieve with our technology if we really have to hurry up.
On the other side of the wormhole they do all sort of manouvres landing on (easy) and leaving planets (difficult) with only a small craft (the Ranger). One would expect you need at least a large rocket to lift off from a planet with 80% of Earth's gravity (the ice world).
It seems they burnt normal fuel in the Solar system and used some very energetic fuel later on. Anyway, who cares, it's only fiction :-)
By the way, does anybody know what kind of rocket would be required to leave Mars and fly back to Earth?