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Fine Structure Constant May Not Be So Constant
BuzzSkyline writes "According to a post at Physics Buzz, 'Just weeks after speeding neutrinos seem to have broken the speed of light, another universal law, the fine structure constant might be about to crumble.' Astronomical observations seem to indicate that the constant, which controls the strength of electromagnetic interactions, is different in distant parts of the universe. Among other things, the paper may explain why the laws of physics in our corner of the universe seem to be finely tuned to support life. The research (abstract) is so controversial that it took over a year to go from submission to publication in Physical Review Letters, rather than the weeks typical of most other papers appearing in the peer-reviewed journal."
So rename it the Fine Structure Variable then.
So how far do we have to go to get out of the Slow Zone?
When this news was published on another news for nerds site (Slashdot is quite slow these days), several commenters brought up Vernor Vinge's novel A Fire upon the Deep . In that far-future musing on the growth of civilizations and technological singularities, Vinge had the Milky Way galaxy divided into various zones which limited how complex technology could be. At the centre, even the simplest machines would fall apart. Further out, electronics and other 20th-century devices worked, but nanotechnology was less effective. Any race moving to the outskirts of the galaxy reached technological progress undreamed of elsewhere.
Vinge made it clear that the Zones were the artificial creation of an ancient advanced race, not the natural result of physics. This news is thought-provoking in that the constants for life and perhaps technology change naturally throughout the universe. It's not just science catching up with science-fiction, but rather science anticipating something generally unexpected., though didn't Poul Anderson write a story of changing laws of physics too?
'“The thing that troubles me about it is [in] the preprint, [t]hey had originally had a supplemental figure at the end that showed the original results for the individual quasars they measured,” Orzel said. He explained that in that figure, the Keck telescope in the Northern Hemisphere seemed to predominantly measure the variation of alpha in one direction while Chile’s VLT in the Southern Hemisphere measured it in going the other way. “It looks a lot like what they’re seeing is coming from a difference between the two telescopes.”'
..
Very much want to see independent confirmation of this result, if instrumentation error hasn't been controlled for
Many astronomical/physics models _ASSUME_ that the universe has the same fundamental laws across the entire universe. If this holds true, it will throw a lot of models into question, including dark energy and dark matter. Personally, I find it very possible that there will be variations across the universe, based on dependencies we don't know/see/understand. Just because I see snow everywhere I look in Antarctica doesn't mean I should expect to see snow everywhere I look in Africa.
"Murderer? Well, that's a harsh word. I prefer to think of myself as a Mortality Technician."
Quasars in the northern hemisphere seemed to have a slightly smaller value for alpha, while those in the northern hemisphere tended to have a slightly higher value.
Schrodinger's Quasars? Both larger/smaller in the Northern Hemisphere?
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
I was just going to say the same thing!
...well actually all i was going to say was "Zones of Thought, here we come!" but close enough for government work :)
Or i could just say that i wrote a long and insightful post, but it suffered from poor translation over multiple relay hops.
This Space Intentionally Left Blank
"may explain why the laws of physics in our corner of the universe seem to be finely tuned to support life"
http://en.wikipedia.org/wiki/Anthropomorphic_principle
The universe is not tuned for life. We are tuned for the universe.
the paper may explain why the laws of physics in our corner of the universe seem to be finely tuned to support life.
Ugh. Logical fallacy. Several of them, actually, depending on how you want to break it down. If the conditions weren't close enough to right, you wouldn't exist to observe the conditions. Therefore, anywhere a consciousness happens to exist is "finely tuned". The conditions could be wildly different from what we are familiar with and life there might be wildly different from what we think is possible, but it would still be "finely tuned" for that life.
In fact, the manipulative bit is the phrase "finely tuned" itself. It implicitly implies that someone is doing the tuning and shifts the balance of discussion into a default state of having a creator.
In one of the physics books I've been reading, it was seriously talking about tachyons and that they could exist in our universe. They even said they probably did exist in the early universe, and it was the instabilities caused by them that helped the universe form. Existence of tachyons would be a sign of a false vacuum. They tachyons form an instability and cause a change to a more stable energy state. This energy state expands at the speed of light till the entire universe (or at least everything inside the Hubble Limit) which would mean new physical constants and different laws of physics. That we are observing two different sets of physics might be a sign of such a energy state change, and luckily, that we are seeing two means that we are already at the newer state. However, if neutrinos actually are acting as tachyons, it might mean we are not done yet (although in a fairly stable spot).
I am not a theoetical physicist, I don't play one on TV and I didn't stay at a Holiday Express last night.
But I've always wondered how we know that the speed of light is the same regardless, that the gravitational constant is constant throughout space and time. Yes, I understand that you have to assume consistency until proven otherwise. Frankly, I am not convinved that the last two "discoveries" will pan out and that we've found non-constant constants. But it confirms to me that this is not a resolved question like so many others have claimed when I have asked the question.
All of it makes me wonder what the mechanism is that determines c or the gravitational constant, the electro weak force and a myriad of other variables that determine the way the universe exists. The only thing that is clear to me is that we understand so freaking little compared to the way the universe must truly be.
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
"The laws of physics in our corner of the universe seem to be finely tuned to support life."
Now don't run into too quick conclusions! We don't really know whether this corner supports life better than the rest of this vast space, do we?
The life is so complicated.
Astronomical observations seem to indicate that the constant, which controls the strength of electromagnetic interactions
This is just too glaringly bad to not bash, although there probably have been worse summaries. The constant does NOT CONTROL ANYTHING about the physical universe, as that is obviously the whole point of this research. It is simply a number which we have determined appropriately models the physics we are able to explore and understand to some degree.
Fear is the mind killer.
Getting really tired of hearing this. Nothing is finely tuned for life. As far as we know, it takes certain conditions for very complex life to form, but that simply means that complex life will only form in those conditions, and here we are. If there were no regions in this universe with the right conditions for complex life we would not be here.
Alpha is actually made up of several constants, as shown in the wikipedia article. So, the question is, if this is indeed the case that alpha isn't constant, which of these 'constants' is actually not a constant? e is the elementary charge. The charge on a proton (-e for an electron). Somehow I think this is unlikely not to be a constant as for all intents and purposes all protons are the same as any other proton, same with electrons. h is the Planck constant, which relates energy to frequency of electromagnetic waves, for example. I'd say that it's a relational constant to create different ways of saying the same thing, so I wouldn't think this is a variable. c is the speed of light in vacuum, 0 is the permittivity of free space, 0 is the magnetic constant or permeability of free space. All three are related by Maxwell's laws. My guess is that it might be one (or all, or some) of these that would be the most likely to not be a variable. Of course, as with the faster-than-light neutrinos, we'll just have to wait for the results to be checked before we can jump to any radical conclusions...
First off, the slashdot summary is somewhat misleading, because the result is not new. Their result was announced in August 2010: http://arxiv.org/abs/1008.3907 . What is new is that they finally managed to get it published in a peer-reviewed journal. You can't judge whether it's right or wrong simply based on whether it's been published in a peer-reviewed journal. Peer review doesn't judge whether a result is right, or whether it can be reproduced. Peer review just tries to judge whether there are obvious mistakes, and things like whether it properly cites the previous literature. The fact that the journal is a prestigious one also doesn't mean it's right; it just means that *if* it were right, it would be of a high level of scientific importance.
Second, it's not really correct to say that the result is controversial. It's not controversial. It's wrong, and the fact that it's wrong is uncontroversial. Just because there's an overwhelming consensus that a result is wrong, that doesn't mean it can't be published in a peer-reviewed journal. Below is a FAQ entry I wrote about this stuff.
Has the fine structure constant changed over cosmological timescales?
It has been claimed based on astronomical observations that the unitless fine-structure constant alpha=e^2/hbar*c actually varies over time, rather than being fixed.[Webb 2001] This claim is probably wrong, since later attempts to reproduce the observations failed.[Chand 2004] Rosenband et al.[Rosenband 2008] have done laboratory measurements that rule out a linear decrease of alpha with time large enough to be consistent with Webb's results.
Webb et al. have recently made even more extraordinary claims that the fine structure constant varies over the celestial sphere.[Webb 2010] Extraordinary claims require extraordinary proof, and Webb et al. have not supplied that; their results are at the margins of statistical significance compared to their random and systematic errors.
Even if their claims are correct, this is not evidence that c is changing, as is sometimes stated in the popular press. If an experiment is to test whether a fundamental constant is really constant, the constant must be unitless.[Duff 2002] If the fine-structure constant does vary, there is no empirical way to assign blame to c as opposed to hbar or e. John Baez has a nice web page discussing the unitless constants of nature.
J.K. Webb et al., 2000, "Further Evidence for Cosmological Evolution of the Fine Structure Constant," http://arxiv.org/abs/astro-ph/0012539v3
J.K. Webb et al., 2010, "Evidence for spatial variation of the fine structure constant," http://arxiv.org/abs/1008.3907
H. Chand et al., 2004, Astron. Astrophys. 417: 853, http://arxiv.org/abs/astro-ph/0401094
Srianand et al., 2004, Phys.Rev.Lett.92:121302, http://arxiv.org/abs/astro-ph/0402177
Duff, 2002, "Comment on time-variation of fundamental constants," http://arxiv.org/abs/hep-th/0208093
Baez, http://math.ucr.edu/home/baez/constants.html
Rosenband et al., 2008, 319 (5871): 1808-1812, http://www.sciencemag.org/content/319/5871/1808.abstract
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http://arxiv.org/abs/1008.3907 Looks pretty much like it, for anyone interested. And as always, extraordinary claims will require extraordinary proof, so we'll have to wait a bit.
We previously reported Keck telescope observations suggesting a smaller value of the fine structure constant α at high redshift. New Very Large Telescope (VLT) data, probing a different direction in the Universe, shows an inverse evolution;
Not to say they definitely *don't* have something, but given that this represents a 180 of their previous report, I'm not going to jump up and down just yet.
So ... they look at one spot on the sky with Keck and discover that the fine structure constant used to be smaller than it is today. Then they look at a different spot on the sky with VLT, and find that the fine structure constant used to be bigger than it is today. So, instead of thinking "Hmm ... the results from these two different observations are contradictory. Perhaps the entire effect is a systematic," they publish a paper in PRL claiming a dipole! Fucking brilliant!
PRL is really getting to be a total joke. Please call me when they look at the same spot with two different telescopes, and different spots with the same telescope. Using the same spectral lines.
Suddenly "A Fire Upon the Deep" seems a little bit less like science fiction.
still no sig
Maybe one day we'll be able to travel to the far reaches of the universe to a location where the laws of physics allow life to suck less.
Sometimes the light at the end of the tunnel is the headlight of an oncoming train.
you can't say. Those all are things that have units, so you can always define them as "1" in the proper set of units. (The speed of light, for example, is always one light-second per second.)
You can still say, because even if you define your units so that the constant is 1 unit, if the constant changes, so does the size of the unit. You can then compare this size with the "previous" size, and get a meaningful ratio. It will be unitless, but still correctly represent that the constant has changed.
Just because we define a constant as X units doesn't mean our definition of the unit automagically changes if the "constant" does. For example, right now the meter is defined in terms of the speed of light. However, if the speed of light changed tomorrow, and you measured it using instruments calibrated today, then your measured m/s would be different.
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Really? Cosmonaut?
It's Confidant
Prepare for downcount.
http://www.youtube.com/watch?v=38UVs8onKKw
Maybe the two anomalies mentioned are just bugs in the software running the matrix...
Sometimes the light at the end of the tunnel is the headlight of an oncoming train.
The article suggests that the change is over time not space.
The real significance is that it would be the first law of physics, aside from entropy that has an arrow of time on it. (And most assume entropy is somehow an artifact of other laws of physics.) Maybe we can reverse this function, so instead of the fine structure constant being a function of time, time is a function of the value of the fine structure constant and its weakening increases the universes entropy.
INAP, but it seems like maybe a decrease in the fine structure constant would increase the tendency of particles to emit and absorb electrons, and therefore make the universe more chaotic over time.
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From TFA:
He explained that in that figure, the Keck telescope in the Northern Hemisphere seemed to predominantly measure the variation of alpha in one direction while Chile’s VLT in the Southern Hemisphere measured it in going the other way. “It looks a lot like what they’re seeing is coming from a difference between the two telescopes.”
Until these findings can be verified by multiple instruments per hemisphere, this looks more like a desperate attempt to save face than present credible data.
So, a few weeks ago we heard that light travels a little bit slower than the fastest objects we've measured. This week we hear that in galaxies far, far away, either the electric charge is larger, Plank's constant is smaller or the speed of light is smaller. If it's the speed of light that's smaller, the required slow-down is of the same order of magnitude as the factor by which photons are slower than neutrinos as observed by OPERA.
Here's my take. There's a field of undetected particles (dark matter?) that refract light a tiny bit, and this field was denser in the early universe. This field would not affect the apparent speed of light as an observer moves through it, just as (ignoring dispersion) light traveling through moving glass doesn't pick up the glass' motion vector (i.e. this wouldn't manifest itself as the Luminiferous aether, which is experimentally disproven).
There: three mysteries (dark matter, OPERA neutrinos and the fine structure "constant") all tied together with a bow on top. If you know more physics than I (honours undergrad) and you think I've missed something, please tear into this hypothesis, either here or on my blog: http://many-ideas.blogspot.com/2011/11/ftl-neutrinos-and-fine-structure.html. I look forward to hearing from you!
Best,
LeDopore
Expected time to finish is 1 hour and 60 minutes.
"The research (abstract) is so controversial that it took over a year to go from submission to publication in Physical Review Letters, rather than the weeks typical of most other papers appearing in the peer-reviewed journal." This is not that unusual...
"...the paper may explain why the laws of physics in our corner of the universe seem to be finely tuned to support life."
Why is the summary parroting this crap? Physics aren't "tuned to support life", life is tuned to the physical constraints of the universe.
I think that we threw out the theory of ether to soon. ;-)
Facts take all of the premium out of arm waving - T. Reynolds
Of course there could be systematic error, but the source must be pretty subtle. The authors have done a pretty large study (in two "two be published" papers).
The implied fine structure constant is derived from relationships among various spectral lines not some large overall effect. The paper mentions that there are 6 quasars which have observations at both telescopes, and they used these data to do some reasonably sophisticated statistical checks.
The best fit to the systematic error corrections between the VLT and Keck appears to statistically insignificant, and the authors also comment that the trend is "different in magnitude and sign for each quasar pair, implying that these effects are likely to average out for an ensemble of observations".
As far as they've seen, search for internal systematics gives a null result, and the fit to a spatial dipole is at 4.2 standard deviations. Each of the two data sets has an internal consistency and the directions of the dipoles (in say galactic coordinates, not local coordinates) from each independently and the combine set agrees.
The authors finish with:
"Qualitatively, our results could violate the equivalence principle and infer a very large or innite universe, within
which our `local' Hubble volume represents a tiny fraction, with correspondingly small variations in the physical constants."
That's their application to the Nobel Committee.
The result is so important that it will need substantially more experimental evidence. I think that this deserves a dedicated spacecraft mission, the way the COBE/WMAP/Planck spacecraft drove the cosmic background analysis.
The universe isn't fine-tuned for life. It is fine-tuned for me.
Let's go where pi is 3.3333...; it sounds much more comforting.
Table-ized A.I.
Neil: "The women in this galaxy are absolutely gorgeous! I cannot believe my eyes! It's one giant leap for Earth men!"
Buzz: "Uh, careful there, Neil; I just found out the hard way that they have wankers."
Table-ized A.I.
Seems like what i have been told was the basis for Lovecraft's writing, except with the extension that visitors from distant stars would bring their "physics" with them.
comment first, facts later. http://chem.tufts.edu/AnswersInScience/RelativityofWrong.htm
Love it :D
Ask anyone that publishes and you will find that it rarely takes just weeks to get a paper published. 4-5 months if you are lucky.
Actually, I got modded "troll", which gave me a pretty good LOL.
The question for me is whether the change in alpha is just based on direction (i.e. the telescopes could be the cause) or if the change is also dependent on distance? If one telescope is seeing bigger changes for objects further away, then the problem is unlikely to just be caused by a systemic error in the telescope.
Sometimes boldness is in fashion. Sometimes only the brave will be bold.
The AC is basically right. Here are a couple of careful discussions of this topic: http://arxiv.org/abs/hep-th/0208093 , http://math.ucr.edu/home/baez/constants.html
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Okay, it seems like the second one is just saying that there are constants whose numerical value is calculable, and constants where the numerical value is arbitrary because of unit choices.
I'm not sure I buy the argument in the first one that because something has units you can't tell when it changes. Yeah, you can say by definition c = 1 light second/second, and that this will be the case whether the speed of light increases or decreases. I maintain though that if tomorrow the speed of light increased by 10%, then when you went to measure it, you would measure it at 1.1 light second/second. You might change the value of your units and unit-conversions (e.g. light-seconds to meters) to account for this so that it is still 1, but this would only happen as a consequence of having observed a changing speed of light.
I mean it basically seems to be saying that if I have a meter stick which is the "standard", and you have a meter stick that's twice as long, and in the middle of the night you sneak in to the building where the meter stick is kept, that the next day nobody would be able to tell the difference.
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I mean it basically seems to be saying that if I have a meter stick which is the "standard", and you have a meter stick that's twice as long, and in the middle of the night you sneak in to the building where the meter stick is kept, that the next day nobody would be able to tell the difference.
Sort of. More to the point, suppose that the fine structure constant changes overnight. Then the meter stick is going to shrink or expand because its size is determined by electromagnetic interactions, and the fine structure constant is a way of parametrizing the strength of those interactions.
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That's an interesting point. Thanks.
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