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Let's Talk About Science! (Or possibly not!science, as it were.)
...after all, the universe may be ending soon.
That's right - the Large Hadron Collider officially started up again today! And I just happened to have wandered into researching it anyway and noticed when I checked Google News. Who wants to take bets on when it's going to break again? :D
You see, there's a theory that the LHC will never be properly operational, because the fact that at some point in the future it might function means the entire universe wants it to fail. Which is why it has so far spent most of its time broken.
No, really.
Holger Nielson and Hayao Ninomiya, two otherwise respected physicists, have published quite a few papers on this theory. Alas, I have not actually read those papers, because the combination of high-level physics and far-from-perfect English very quickly defeated me. Sean Carroll explains the Nielson-Ninomiya theory (and links to his original papers) in his discovermagazine blog in a way that laypeople might possibly be able to understand, at least a little bit, although it involves imaginary numbers applied to physical properties, which I have not yet figured out how to make comprehensible.
But a) this theory is awesome and science-fiction-y, and b) I think it might actually solve a plot hole in my pet form of fictional ftl travel, so I have attempted to understand it anyway.
1. Usually, when we discuss physical causality, we think of it in terms of "I pushed a ball, and because my push imparted energy to the ball, it rolled." But we can also think in terms of "I pushed the ball, and because it rolled, my push imparted energy to the ball." For the duration of this exercise, we are using the second way of thinking.
2. We can assume that it was my push that imparted the energy to the ball, instead of, oh, a freak split-second gust of wind, or a magic man in the sky, because one of the basic physical laws of the universe is that it is lazy: anything that happens, happens in the way that requires the least possible effort. (This is so basic that it's essentially Newton's First Law, but it is remarkably extensible beyond that. All systems seek the path of least resistance.)
3. This means that if you know starting and ending conditions (I pushed the ball, the ball rolled), you can deduce everything else that happened in a sequence (my push imparted energy to the ball), and by extension, everything that happened before and after two arbitrary known events (the ball existed, I exist, gravity exists, the sun coalesced and ignited, the ball rolled under the chair and a cat attacked it...) In other words, start thinking in terms of timelines rather than sequences of discrete events which occur semi-independently.
4. However, the Uncertainty Principle in quantum mechanics, and some other stuff, means that it is impossible to know exact starting and ending conditions. All you can do is calculate probabilities: given the relative probabilities of certain events happening, you can look at all the possible timelines that would create each of those probable events, and then say that the ones that are most likely to actually exist are the ones that require the least action.
5. You can actually calculate Action as a number: it is the sum, over every point in a timeline, of the difference between kinetic energy (energy of doing) and potential energy (energy of being). In other words, the greater the value of the Action, the more stuff has happened. The lower the value of the Action, the less stuff has happened. The most likely timelines are those with the lowest Action.
6. This is all the sort of thing that undergraduate students are expected to understand; the crazy bits come when Ninomiya and Neilson decided to pretend that the value of Action could be partly imaginary. Imaginary math is complex, and I don't actually understand how they apply it to real-world values, but a) physicists do use it all the time, and b) it doesn't really matter, because Ninomiya and Neilson are basically just playing "What if?" and leaving "Why" and "How" to other people.
7. Essentially, what this means for our current discussion is that Action, instead of being a number that is either greater or less, is a complex number that would have two parts: a real part, and an imaginary part. A timeline with what seems like a low value for real Action, because not a lot is happening, might, if you take into account what's happening with the imaginary part that we used to ignore, not actually be a very efficient timeline. And therefore, a timeline that *seems* like the laziest possible timeline might actually be extremely unlikely - and a timeline that seems, on the level of real numbers, almost infinitely improbable, may be the timeline that really exists.
8. We of course have no idea what this imaginary Action component might be, since we just made it up, so Ninomiya and Nielson picked some possible values for it, and played with the numbers until they got something that was both interesting, and described a universe that might be our universe.
9. It turns out that one of these interesting-and-possible solutions results in a universe where the imaginary component of Action only applies in timelines in which there are large numbers of Higgs bosons. In other words, any timeline in which there are large numbers of Higgs bosons (at any point in the timeline) is a timeline with a significant Imaginary action, and therefore, no matter how logical it seems on the surface, such timelines are extremely unlikely to exist.
10. It's so unlikely to exist that all kinds of bizarre coincidences are more likely than a universe with lots of Higgs bosons in it. In fact, when the alternative is the creation of Higgs bosons, million-to-one chances crop up nine times out of ten.
11. This means any project which is theoretically capable of generating Higgs bosons is going to have what appears to be terrible luck: electrical connections will fail at the worst possible moments, birds will happen to drop bits of bread in exactly the wrong place at exactly the wrong time, funding will be unexpectedly cut off, etc., etc, until the project is abandoned. Because nearly anything is probable, compared to the probability of a timeline existing in which Higgs bosons have been, or will ever be, generated.
12. The Large Hadron Collider, if it ever functions properly, will generate large numbers of Higgs bosons. Therefore, it will be plagued with what appears to be "bad luck" to the extent that it never properly functions.
Okay, this is theorizing *way* in advance of the data and out in left field, but it is (according to above real-physicist's-blog and a few others, and my own vague attempts at understanding it) not *completely* off the wall, and in fact it doesn't contradict anything currently known. And all revolutionary scientific theories theorize ahead of data. The way to tell if a pie-in-the-sky theory is worth considering or not is to see if it is *predictive*: 'we don't have any evidence yet, but if our theory is true, this particular piece of evidence will turn up soon."
The Nielson/Ninomiya papers predict only one verifiable result: that the Large Hadron Collider will be plagued with difficulties, delays and "bad luck," and never actually generate significant numbers of Higgs bosons. The theory was first published in 2007, a year before the collider was scheduled to begin operation, and when everything seemed to be going smoothly for it.
Since then, full operation has been pushed back repeatedly due to difficulties, delays, and "bad luck", and the time at which it will be ready to generate Higgs bosons is not known....
(Do I actually take this theory seriously? About as seriously as I take the theory that the moons of Mars are spaceships that arrived in the Solar System in the mid-19th century. I'm pretty sure even the authors don't take it too seriously, considering the experiment they proposed is to set up an *actual*, calculated million-to-one chance, and bet the operation of the LHC against it, and if that million-to-one chance does come up, well, you've simultaneously proved their theory and the existence of the Higgs boson, and you can shut down the LHC and save a lot of money...)
(But it *could* be real, and that sort of playing around is important in science and nobody does it enough anymore, and also it's dead fun.)
(Plus, I can define magic as being the high probability of the occurrence of apparently unlikely events, which by this theory would be quantified as the effect of "imaginary action". And that's *lovely*.)
(Also, I think it proves Niven's Law backwards. And possibly that the Hitchhiker's Guide to the Galaxy is nonfiction.)
That's right - the Large Hadron Collider officially started up again today! And I just happened to have wandered into researching it anyway and noticed when I checked Google News. Who wants to take bets on when it's going to break again? :D
You see, there's a theory that the LHC will never be properly operational, because the fact that at some point in the future it might function means the entire universe wants it to fail. Which is why it has so far spent most of its time broken.
No, really.
Holger Nielson and Hayao Ninomiya, two otherwise respected physicists, have published quite a few papers on this theory. Alas, I have not actually read those papers, because the combination of high-level physics and far-from-perfect English very quickly defeated me. Sean Carroll explains the Nielson-Ninomiya theory (and links to his original papers) in his discovermagazine blog in a way that laypeople might possibly be able to understand, at least a little bit, although it involves imaginary numbers applied to physical properties, which I have not yet figured out how to make comprehensible.
But a) this theory is awesome and science-fiction-y, and b) I think it might actually solve a plot hole in my pet form of fictional ftl travel, so I have attempted to understand it anyway.
1. Usually, when we discuss physical causality, we think of it in terms of "I pushed a ball, and because my push imparted energy to the ball, it rolled." But we can also think in terms of "I pushed the ball, and because it rolled, my push imparted energy to the ball." For the duration of this exercise, we are using the second way of thinking.
2. We can assume that it was my push that imparted the energy to the ball, instead of, oh, a freak split-second gust of wind, or a magic man in the sky, because one of the basic physical laws of the universe is that it is lazy: anything that happens, happens in the way that requires the least possible effort. (This is so basic that it's essentially Newton's First Law, but it is remarkably extensible beyond that. All systems seek the path of least resistance.)
3. This means that if you know starting and ending conditions (I pushed the ball, the ball rolled), you can deduce everything else that happened in a sequence (my push imparted energy to the ball), and by extension, everything that happened before and after two arbitrary known events (the ball existed, I exist, gravity exists, the sun coalesced and ignited, the ball rolled under the chair and a cat attacked it...) In other words, start thinking in terms of timelines rather than sequences of discrete events which occur semi-independently.
4. However, the Uncertainty Principle in quantum mechanics, and some other stuff, means that it is impossible to know exact starting and ending conditions. All you can do is calculate probabilities: given the relative probabilities of certain events happening, you can look at all the possible timelines that would create each of those probable events, and then say that the ones that are most likely to actually exist are the ones that require the least action.
5. You can actually calculate Action as a number: it is the sum, over every point in a timeline, of the difference between kinetic energy (energy of doing) and potential energy (energy of being). In other words, the greater the value of the Action, the more stuff has happened. The lower the value of the Action, the less stuff has happened. The most likely timelines are those with the lowest Action.
6. This is all the sort of thing that undergraduate students are expected to understand; the crazy bits come when Ninomiya and Neilson decided to pretend that the value of Action could be partly imaginary. Imaginary math is complex, and I don't actually understand how they apply it to real-world values, but a) physicists do use it all the time, and b) it doesn't really matter, because Ninomiya and Neilson are basically just playing "What if?" and leaving "Why" and "How" to other people.
7. Essentially, what this means for our current discussion is that Action, instead of being a number that is either greater or less, is a complex number that would have two parts: a real part, and an imaginary part. A timeline with what seems like a low value for real Action, because not a lot is happening, might, if you take into account what's happening with the imaginary part that we used to ignore, not actually be a very efficient timeline. And therefore, a timeline that *seems* like the laziest possible timeline might actually be extremely unlikely - and a timeline that seems, on the level of real numbers, almost infinitely improbable, may be the timeline that really exists.
8. We of course have no idea what this imaginary Action component might be, since we just made it up, so Ninomiya and Nielson picked some possible values for it, and played with the numbers until they got something that was both interesting, and described a universe that might be our universe.
9. It turns out that one of these interesting-and-possible solutions results in a universe where the imaginary component of Action only applies in timelines in which there are large numbers of Higgs bosons. In other words, any timeline in which there are large numbers of Higgs bosons (at any point in the timeline) is a timeline with a significant Imaginary action, and therefore, no matter how logical it seems on the surface, such timelines are extremely unlikely to exist.
10. It's so unlikely to exist that all kinds of bizarre coincidences are more likely than a universe with lots of Higgs bosons in it. In fact, when the alternative is the creation of Higgs bosons, million-to-one chances crop up nine times out of ten.
11. This means any project which is theoretically capable of generating Higgs bosons is going to have what appears to be terrible luck: electrical connections will fail at the worst possible moments, birds will happen to drop bits of bread in exactly the wrong place at exactly the wrong time, funding will be unexpectedly cut off, etc., etc, until the project is abandoned. Because nearly anything is probable, compared to the probability of a timeline existing in which Higgs bosons have been, or will ever be, generated.
12. The Large Hadron Collider, if it ever functions properly, will generate large numbers of Higgs bosons. Therefore, it will be plagued with what appears to be "bad luck" to the extent that it never properly functions.
Okay, this is theorizing *way* in advance of the data and out in left field, but it is (according to above real-physicist's-blog and a few others, and my own vague attempts at understanding it) not *completely* off the wall, and in fact it doesn't contradict anything currently known. And all revolutionary scientific theories theorize ahead of data. The way to tell if a pie-in-the-sky theory is worth considering or not is to see if it is *predictive*: 'we don't have any evidence yet, but if our theory is true, this particular piece of evidence will turn up soon."
The Nielson/Ninomiya papers predict only one verifiable result: that the Large Hadron Collider will be plagued with difficulties, delays and "bad luck," and never actually generate significant numbers of Higgs bosons. The theory was first published in 2007, a year before the collider was scheduled to begin operation, and when everything seemed to be going smoothly for it.
Since then, full operation has been pushed back repeatedly due to difficulties, delays, and "bad luck", and the time at which it will be ready to generate Higgs bosons is not known....
(Do I actually take this theory seriously? About as seriously as I take the theory that the moons of Mars are spaceships that arrived in the Solar System in the mid-19th century. I'm pretty sure even the authors don't take it too seriously, considering the experiment they proposed is to set up an *actual*, calculated million-to-one chance, and bet the operation of the LHC against it, and if that million-to-one chance does come up, well, you've simultaneously proved their theory and the existence of the Higgs boson, and you can shut down the LHC and save a lot of money...)
(But it *could* be real, and that sort of playing around is important in science and nobody does it enough anymore, and also it's dead fun.)
(Plus, I can define magic as being the high probability of the occurrence of apparently unlikely events, which by this theory would be quantified as the effect of "imaginary action". And that's *lovely*.)
(Also, I think it proves Niven's Law backwards. And possibly that the Hitchhiker's Guide to the Galaxy is nonfiction.)
This post needs more video illustration.
http://www.hulu.com/watch/105298/the-colbert-report-big-bang-theory
Re: This post needs more video illustration.
http://www.hulu.com/watch/105295/the-colbert-report-sign-off-future-stephen
Re: This post needs more video illustration.
Stephen Fry, QI, and a physicist explain Higgs bosons and time travel (incidentally, also the episode that demonstrates what happens when a British physicist meets his antimatter counterpart.)
Or for the less high-brow version HIGNIFY on what broke the LHC!
Also, you neglected to link to the Colbert bit with the hot British physicist (no antimatter counterpart, alas.)
...they all really gloss over the actual science involved, though. The time-travel description is kind of a red herring. Hence the text version. :P
(Did you know that the guy who did A Glorious Dawn Awaits has a new track out? Featuring the autotune stylings of Neil deGrasse Tyson?)
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(I'm scared of posting it on science, because there is a fairly high risk in that case that a Real Physicist might read it, and attempt to explain to me what I've got wrong, which would be both futile and depressing. :P)
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Also, "Imaginary math is complex" is an intentional pun, yes?
I do hope this theory is wrong, though, because I have a friend who went to the LHC and I'd like her to get her PhD at some point. :(
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And yes, the pun was intentional. :D
I'm sure they'll discover other things while in the process of not discovering the Higgs boson!
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That said, steps 9-12 rock my socks off. I'm not sure I actually believe it (I'd want a much longer timeline to take as evidence), but damn is it cool. I can see why some people call the Higgs the "god particle" now.
I've read at least one set of books in which magic is the ability to manipulate probability.
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The example used in the original work: you cannot hit a billiard ball through a time portal such that it will knock itself off course and miss the time portal, because if you try, a billiard ball will come through the time portal and mess up your aim just enough that instead of knocking the billiard ball away from the time portal, it will just mess up your aim a little bit.
...they have done the math. They have proven that, in a universe where time travel happens via closed timelike curves, not only would this work, there is no possible set of initial conditions for which it would not work, and you can use the same "principle of least action" to determine the most likely angle at which the ball will emerge from the time portal.
...and then somebody went and said, "Wait, if you can predict the angle at which it emerges, that basically means you can *send yourself information from the future*, and someone - not an SF writer, a real scientist - has actually written a hypothetical computer program that performs mathematical calculations by setting up a situation where a paradox will happen if the correct answer does not appear from the future.
Physics is *deeply awesome*.
And yet, 90% of the SF stories I've encountered that use something like that in time travel physics either refuse to explain or develop it, or end up going somewhere ludicrously anthropomorphic with it, attributing intention, when the awesome part is that you don't *need* anything more elaborate than apparently silly coincidences happening, because it seems that the universe believes in the law of narrative causality.
And magic has been blamed on probability manipulation at least as far back as the Scarlet Witch's debut in X-Men in 1964 (and probably earlier!)
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