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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.
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.
So basically what he's saying is we might as well dump the money into a black hole. Sounds like most government programs.
Taking guns away from the 99% gives the 1% 100% of the power.
I am so disappointed.
I like microcars
He's talking needing energies that would make Doctor Who's Tardis, powered by an exploding supernova, gasp in disbelief.
I'm all for breakthroughs, but geeze.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
It's all theory work. Money isn't the limiting factor there, it's just that very few people have the required intellect and level of education to advance the field. There's nothing to spend money on until some of them propose an experiment to test their latest theory. Even the particle physics people can ask for new accelerators, and cosmologists always have some new instrument on their wish-list.
The only hope for fundamentally new space travel tech right now is the quantum vacuum thruster, and that only because the experimental evidence so far has too many flaws to say anything more than 'something funny going on here.'
Why is Scientific American even running such an article?
What's next? Supposedly-serious newspapers "fact-checking" a comedy sketch?
FTFY.
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.
"physics very probably forbid warp drives and traversable wormholes."
I would imagine that the human understanding of physics 50 years ago would have forbid the creation of the kind of microelectronics/transmitters/battery technology that are commonplace in most of our pockets today. Admittedly the physics of FTL (or any interstellar travel method) are far more difficult than what we have done in the electronics field over the past few decades, but believing that our pre infantile understanding of the universe makes us in any way knowledgeable of what is and is not possible is hubris of the highest degree.
I can't be alone in not liking this film. It wasn't the science (there was obviously a lot of work done there) that bothered me, and besides which with Sci Fi you always get a 'gimme' or two (warp drive, transporters, technobabble etc) but I really didn't feel anything with the story. It didn't draw me in, it just dragged. This wasn't what I was expecting as I had been looking forward to this film since I saw the first teaser. 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?
"I have the attention span of a strobe lit goldfish, please get to the point quickly!"
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.
Well, think of it like this.. with limiting factors such as the speed of light, or planck length, those tend to be rather concrete 'limits' to technology. So unless our understanding of those limits is 'wrong', it's not like they can just be removed by some handwaving and dilithium crystals.
Your comparison to electronics 50 years ago was purely a lack of understanding of materials science. To create a transistor there's nothing in the fundamental physical laws that preclude its construction, thus requiring a workaround to construct.
its that other movie playing when you go see hunger games
... but have huge amounts of evidence that indicae they're not THAT wrong.
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 don't believe I've ever seen a modem break 56 Kbps over a phone line.
This kind of comment is deeply ignorant and anti-science. Relativity is a description of the geometry of the universe. If you would rather believe in your own personal fantasies instead of one of the most well-supported theories in science, congratulations, you are yet another variety of religious loon.
Look, it's pretty simple. Science is not magic, and there is shit that it says that is for real-real not for play-play. We don't know what the future will look like in 2050 or 2100, but we can be completely sure of three things:
1) There will be no violation of the Laws of Thermodynamics.
2) Nothing (for all important values of nothing) will travel faster than the speed of light.
3) Commercial fusion power will still be 20 years out.
The first two are immutable laws of physics, the final one was proven by a Dr. M. T. Budget. Humor aside, relativity and thermodynamics have been proven at both the largest and smallest scales that humans have been able to observe, and at every level in between. They are not perfect theories, but they do place very hard and very real constraints on what kind of rabbits you can pull out of a given hat. You will not go to intergalactic space today, nor tomorrow, nor while anything recognizable as human exists.
Those who advocate genocide deserve every protection afforded by law, and none afforded by common human decency.
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.
physicist have to eat. And raise families and live like civilized people who have actual lives. This of course is incomprehensible to some US TV viewers who suspect that Big Bang Theory is just slightly not a documentary. People are as amazed watching Tyson and Hawking hold their own on Colbert or Oliver a if they had just seen a talking squirrel. So it'll be an uphill slog for a while here. It takes money for faculty positions and the time to do the work. Einstein's work was pure theory until it was tested, but you never get to test it unless someone has the theory. So yes. Pay for it. Just as you pay coders to come up with new models for how things can work - also completely useless until they see the inside of a machine that actually does something with the code.
"Win treats sysadmins better than users. Mac treats users better than sysadmins. Linux treats everyone like sysadmins."
*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?
The worst physics didn't involve strong gravity fields or high velocities or accelerations. Just Newton's Third Law and an energy argument. The second-worst bit of science was biological, but also involved an energy argument.
Spoilers:
1) Matt Damon's spaceship just would have been gently pushed away when he opened the airlock. Maybe gently pushed to one side or another depending on the partial seal. It certainly would NOT have set the entire Endurance vehicle spinning like mad.
2) The blight was better adapted because it utilized nitrogen from the air instead of oxygen? Yeah I don't think so; what do you combine with N2 that yields energy instead of spending it?