from the but-what-about-the-hula-hoops? dept.
(*Spoiler alert: This post refers to key elements of the movie.)
If we can walk backwards and forwards in space, why not in time?
Scientists, especially theoretical physicists, like to play such games — controlling time with pencil and paper. Going forward in time, traveling to the future, is actually OK, according to the Theory of Relativity. All we need is a super-fast spaceship, traveling close to the speed of light. A technological, and not a conceptual obstacle.
Going back in time is more complicated. Much more. Remarkably, closed-time loops are not just the stuff of sci-fi stories. (Why a closed-time loop? Most people don't want to go back in time and be stuck there. A short visit to the past should suffice.) In 1949, the brilliant Austrian mathematician Kurt Gödel found a solution of Albert Einstein's equations of general relativity where it is possible, at least theoretically, to travel in a circle in time as we can in space, returning back to the starting point. The movie brilliantly plays with this notion, not least since 13.7's own Adam Frank worked as a scientific consultant.
In practice, Gödel's solution and any of its modern versions are a very, very long shot. There are issues with how to keep such spacetimes from collapsing upon themselves, not to mention weird time paradoxes like the Grandfather Paradox: If you travel back in time and kill your grandfather before he marries, would you exist? However, in a Marvel universe it is possible. When Dr. Strange discovers that he has this power, we see a disturbingly beautiful image of an apple being eaten and reassembled again and again, a small patch of space where a closed-time loop is possible.
(Score: 3, Interesting) by FatPhil on Tuesday December 06 2016, @10:09AM
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 0) by Anonymous Coward on Tuesday December 06 2016, @10:27AM
it's like a movie.
you can rewind it, play it at different speeds all you like, the different frames will always be the same.
if you want to call it "traveling" call it that, but it makes no sense.
closed time loops?
they are possible, they don't break causality (so stop talking about the stupid grandfather paradox), but because they don't break causality you can't tell you're in one.
(Score: 4, Informative) by GreatAuntAnesthesia on Tuesday December 06 2016, @10:59AM
I'm not going to comment on the physics of the new Dr Strange film because IANAP (other than to say that if less people got their scientific "education" from Marvel stories[1] then the internet would be a better place)
I just wanted to say that if you haven't watched the film yet, it's a great watch. Cumberbatch is really good as Strange: His mixture of arrogance, competence and charm is reminiscent of RDJ's Tony Stark, but it is in no way derivative. You do get the impression that that is the kind of personality (or one such personality) required to wield such vigilante power with a measure of responsibility. It's a sign of the post-Watchmen era that Marvel feels the need to answer the question "exactly what sort of person would it take to put on a costume and go beat up bad guys?"
The effects are stunning, and that's not normally something that factors into my film reviews. The characters are good, the story is decent (pretty standard superhero fare, but it all flows with no gaping plot holes that I could detect), there are plenty of amusing moments (especially with the cape) and like Guardians of the Galaxy, it doesn't require any other investment in the Marvel Cinematic Universe, but you can see how it does all knit together.
Go see it.
[1] In particular, there seem to be a lot of people out there whose understanding of evolutionary theory seems to be entirely based on the X-Men films.
(Score: 1, Informative) by Anonymous Coward on Tuesday December 06 2016, @11:14AM
Small addition: See it in 3D. It's one of the few films where 3D is worth it.
(Score: 1) by DeVilla on Friday December 09 2016, @05:06AM
I have to second this. This is the only film I've seen where 3D was well used and not just a stupid gimmick. I saw the iMAX 3D version and if motion sickness isn't a problem for you (my wife can't watch iMAX or 3D) it does genuinely add to the movie.
(Score: 2) by art guerrilla on Tuesday December 06 2016, @11:45AM
don't have anything against cucumber, but was not liking him as khan in into the darkness star trek movie... too restrained, too tight, not loose and free-wheeling like ricardo was... not sure what the community consensus was on that, but obviously ricardo montelban was absolutely pitch perfect for the original khan, and i found cucumberpatch lacking in many ways, NOT just that he wasn't ricardo montelban (who is?), but that he didn't have the germ of what khan would 'become' (a la the movie/teevee timeline), the khan we loved to hate...
(Score: 2, Interesting) by kurenai.tsubasa on Tuesday December 06 2016, @02:45PM
Everything that made Cumberbatch a brilliant Sherlock Holmes or Dr. Strange is what's working against him as Khan. Khan is exceedingly charismatic and passionate, which makes him all the better megalomanic. Also the plot of JJTrek into Fail is just weird. So the Federation goes out and grabs the Botany Bay because they want Khan, and Khan and the rest of the enhanced humans just allow this to happen? Why do they need Khan, specifically, anyway? His magic space blood? lol
(Score: 0) by Anonymous Coward on Tuesday December 06 2016, @12:10PM
laws in physics are post facto rationalizations.
does an equation let you travel back in time? means nothing until you discover how. Dark matter is a factor to fix equations, until it is detected. The em drive works? laws must be reinterpreted to allow it.
(Score: 0) by Anonymous Coward on Tuesday December 06 2016, @02:55PM
When it comes to time loops, I prefer the lesson of another Doctor:
(Score: 3, Interesting) by tangomargarine on Tuesday December 06 2016, @03:09PM
In 1949, the brilliant Austrian mathematician Kurt Gödel found a solution of Albert Einstein's equations of general relativity where it is possible, at least theoretically, to travel in a circle in time as we can in space
I was under the impression that when somebody comes up with a bizarre application of general relativity, it usually means that GR doesn't cover the area and you need quantum mechanics to get involved.
Not that I'm not a big sucker for a decent time travel story :)
"Is that really true?" "I just spent the last hour telling you to think for yourself! Didn't you hear anything I said?"
(Score: 0) by Anonymous Coward on Tuesday December 06 2016, @03:15PM
No, Gödel's solution is purely GR. However you need a rotating universe.
(Score: 2) by tangomargarine on Tuesday December 06 2016, @05:37PM
That was my point? How is this a "no" statement?
Some of these "solutions" involving GR solve a problem that only exists in GR; if you look at it in a quantum mechanical context the "problem" vanishes.
IANAPhysicist
"Is that really true?" "I just spent the last hour telling you to think for yourself! Didn't you hear anything I said?"