In fact, I'd argue that every step towards a total understanding of our universe, no matter how small the step, is worth virtually any cost placed on it.
I agree with you 100%, but my application of this sentiment differs from yours. It's a shame when only a few dozen bits are discovered when the same effort could have lead to enormous gains in other fields. That's why I encourage scientists away from particle physics and into other areas like biophysics, nonlinear physics, fluid dynamics, bioengineering, neuroscience, machine intelligence and applied mathematics.
The only way the LHC makes sense is if you believe one bit of particle physics knowledge is worth millions of times more than one bit of neuroscience knowledge, since there might be a million to one ratio of understanding per effort spent. By your signature, it looks like you might still think that particle physics knowledge really is a million times more important than knowledge in any other field. Different strokes for different folks, I guess.
'Either would be a major advance in our exploration of nature, bringing us closer to understanding how the fundamental particles acquire their mass, and marking the beginning of a new chapter in particle physics.'
I can't help but point out that knowing if the Higgs exists will increase our information about the universe by a maximum of 1 bit. (Knowing its mass and decay modes probably would give us more like a dozen or two bits of information - more than 1 bit but still not much.)
Particle physics is great, and doing it carefully *does* increase our knowledge of the world, but only by the tiniest of margins. Imagine if all those thousands of super-bright minds had been focused on some other task for decades? What kind of magic tech would we have by now? The ratio of opportunity cost to benefit is sky high.
Physics is using math to predict what matter will do in certain circumstances. (I find that pretty mind-blowing - that you can *calculate* what will happen to *stuff* if the system is simple enough. Too bad the calculation approach didn't work out for me so well in the girlfriend department in high school - another story.)
Anyway, the math behind how positive and negative charges attract is the same as the math behind how masses attract: they're both "inverse square laws." Three times the distance, one-ninth the force, since 3 squared is nine.
That means that the motion of a charged water droplet around the needle will be the same type of motion as orbiting, which is why it looks just like gravity. The math is the same, so the motion is the same.
There's been some really promising work in the direction of OCR-like problems lately. Here's an algorithm that can efficiently learn a small dictionary of symbols (like letters) and decompose a signal into elements that fit within this "low-rank" dictionary plus sparse noise (bugs squashed on the text?) plus Gaussian noise: https://sites.google.com/site/godecomposition/.
It's not literally magical, but it's super-duper awesome (an no, I'm not an author of this one) and it should contribute to the minor revolution in signal processing (compressed sensing & low-rank matrix completion) that's been gaining momentum since about 2005. If our machines can learn features efficiently and robustly from natural images, many industries are in for a wild shake-up. More on this minor revolution is available at http://nuit-blanche.blogspot.com/.
These algorithms are part of the reason why self-driving cars are starting to work, and I have the excited feeling like we're on the cusp (read, next ten years or so) of a sea change in our ability to have machines able to understand and interact with the physical world with a dash of common sense.
You are largely correct. Most software has not sped up much since the 1970s, and it could even be argued that developers write such sloppy code these days that even our improved compilers can't compensate, especially in applications where performance is no longer critical.
These advances are not just academic games; they are actually worth doing. They could eventually lead to computers with sensory processing routines that have a mote of common sense to them, able to perform some real-world tasks we currently need humans for.
While I agree that by and large, most software is getting fat and lazy, there are a few problems where today's algorithms on 2002 hardware mop the floor with 2002 algorithms on today's hardware.
There's a lot of talk as to what you should do while an after the prof is speaking, but so far very little has been said about what to do *before* the professor speaks it. During my Physics undergrad, I would challenge myself to try to derive results and formulas before the prof finished. I was often wrong, and I usually had to have my notes at least nudged along at least a few times per lecture, but trying to derive on the fly is an awesome way to learn something. There's nothing quite like figuring out a problem by yourself to have it really gel with your overall understanding.
That's my advice: rather than just trying to learn, as much as possible *do your own thinking* in class and you'll be amazed at how little you have to work later to recall it.
Are you saying patent royalties are the only expense when it comes to new technology ?
No, but developing one SDR that works for all phones in 50 countries without worrying about patent infringement certainly sounds like a good way of getting a high ROI when investing in a new technology. Of course there's a lot of work and expense, but I think SDRs are still a great way to go, especially since the best ones now (unlike even 2 years ago) perform almost as well as hardware-defined radios.
I grant that it's always possible to do at least a little better when you know the frequencies you'll use at design time than if you have to have a software defined radio.
That said, Caroline Andrews of the lab I worked in (http://molnargroup.ece.cornell.edu/research.html) developed a software-defined radio using a passive mixer that works in the GHz range with only 1 dB worse noise for the same power as you would use with a fixed radio. She also showed how a software defined radio can do impedance matching through the passive mixer. Amazing, possibly game-changing stuff; if you really are a cellphone radio engineer, don't assume that software-defined radios will always suck hard enough not to be a threat.
By the way, on behalf of Slashdot, YOU'RE WELCOME FOR TEACHING YOU HOW TO DESIGN A PHONE!
Not necessarily. This lab from Cornell isn't going to patent their SDR, and it's a pretty sweet implementation: noise performance almost as good and chip area only slightly larger than a single-band ASIC:
Does it really matter where they're made? The companies that own the intellectual property are the ones making most of the profit. If a company in China charged enough to make a killing on manufacturing, the owners could look to another company to fill the orders instead. Need proof that this actually happens? Look at how Vietnam is stealing manufacturing jobs from China.
China gets a bad rap, and they might deserve it due to poor labor practices, environmental standards and safety policy. Complain about those issues - I'll likely join you. They don't however deserve to be vilified because they're bleeding us dry with their over-priced manufacturing costs - that betrays a fundamental misunderstanding of the free market. If anything, having a place where manufacturing can be done cheaply is actually a good thing.
Case in point: I'm considering starting to manufacture a niche electronics gizmo for neuroscientists. Using a Chinese company to manufacture most of the hardware (but keeping the final steps in-house to maintain secrecy and avoid the possibility of clones appearing) I should be able to get my first revenue after only a $6,000 investment. My gross profit margin will be 400% - the Chinese are working hard for their tiny 20% share of the pie, and I don't begrudge them their pittance, since neither half of this "partnership" would be viable without the other.
"A few hackers, in their spare time, with no documentation about the hardware, and without the software keys theoretically required to obtain full access to it, managed to do what the multinational corporation that designed the phone said was impossible to do. "
Point taken. However, you might be surprised at how little resourcefulness can be found in multinational corporations. The best talent doesn't always find its way there, and sometimes a small number of brilliant individuals can make progress staggeringly faster than a larger number of pretty-good engineers working 9-5 under corporate processes and restrictions.
Phase velocity is w / k. Group velocity is (dw)/(dk). If there's no dispersion, you scale k by a constant factor n slightly greater than 1. This slows both phase and group velocity by a factor of n, if w is proportional to k. If light is interacting with dark matter, you're right that it would interact with each particle extremely weakly, so there would have to be a whole lot of them. Also, probably the transitions would be of such high energy that you wouldn't get noticeable dispersion, so phase and group velocity would be equal.
I'm not in a position to comment on the likelihood of densities of dark matter. I'm not even sure how anyone could predict this with confidence, but you seem pretty sure of it. How do you set limits on the density of a particle with unknown properties you haven't observed yet (not facetious - genuinely interested)?
OPERA shows light travels little bit slower than the fastest objects we've measured. A little while ago we heard that in galaxies far, far away, either the electric charge is larger, Plank's constant is smaller or the speed of light is smaller (http://slashdot.org/comments.pl?sid=2507746). 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 disproved). Light from the 1987A supernova would not be delayed too much relative to the neutrinos because most of the journey was through regions of space with low dark matter density.
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!
My father works at a law firm, and they do remote incremental backups over ssh. I don't really expect that anyone is recording all ssh traffic for later cracking, but on the other hand it would be easy to do. Law firms have all sorts of documents, including a few really secret ones that could incriminate clients. Lawyer-client privilege exists for a reason.
In any case, if ssh fails in 20 years, law firms will be screwed. With documents like these, I have to think ssh isn't good enough, since a 10% chance (rough estimate) of losing all your data in 20 years is an unacceptable risk.
High energy physics almost always refers to energy levels far above standard nuclear reactions. Lightning discharge is plasma physics, but the process behind how charges build up is still mysterious. The experiments conducted at CERN will not lead to technological advances you and I will see in this lifetime - indeed siphoning off money and talent to these projects *harms* the advancement of small-scale but useful science. I'm a scientist working on small projects, that's why I'm bitter.
I have nothing against particle physics per se, but the big projects are so inefficient that their funding is inevitable. When a project requires 10,000 human-years to complete, you can bet they have their grant proposals pretty slick, and politicians love to fund big endeavors, especially when pork barrels come into play. Small-scale geeks working in real-world situations that could have an impact on real-world issues have to beg for scraps from the table of big science.
I would be happy to see funding moved from high energy particle physics towards fields that could potentially yield a benefit to humanity. Like, for example, almost any other scientific investigation.
Nothing against you or your friend personally, but we still don't know how charge is built up in clouds to cause lightning. Why is there so much funding to study CP violation/Higgs bosons, etc. when we still don't understand lightning?
No, your plans for galactic empires are pretty safe: the changes in alpha are only on the order of ten parts per million. At most, bond strengths would be different by about that amount in long-ago galaxies (note, probably by now alpha is more uniform everywhere).
Now, if my hypothesis is correct and if we could make an extremely concentrated dark matter beam that could slow down the speed of light tremendously for all objects in its path, it could seriously alter the chemistry of anything it hits. The target's colour would change, chemical bonds could break, etc. How's that for a weapon to keep your imperial galactic subjects in line?
To be clear, I'm not proposing my hypothesis has been sufficiently demonstrated yet to be convincing. It's not even a theory yet, and I don't have the time or training to make it one. Moreover, even if it's correct, dark matter interacts extremely weakly with anything else - that's why it's dark - so making a beam of the stuff would be so difficult it would hardly qualify even as science fiction. Still, it's fun to think about!
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!
Want to reduce scan times? Check out compressed sensing MRI [1]. You should be able to take way fewer scans than thought possible with 20th century math. Regularized reconstructions are the new hotness, but don't take the word of a Slashdot user who says "dude" and "new hotness"; read these fricking things.
[1] M. Lustig, D. Donoho, J. Santos, and J. Pauly, “Compressed sensing MRI,” IEEE Signal Processing Magazine, vol. 25, no. 2, pp. 72–82, 2008.
I've noticed a disturbing trend that as funding levels drop, agencies are receding more to their core areas of study and leaving interdisciplinary scientists high and dry. Furthermore, it seems that there's an inverse relationship between the fund-ability of a project and its efficiency: if a (say) particle physics project is so inefficient it requires 1000 scientists 10 years to get 1 bit of data (like the Top quark discovery) then they're guaranteed to have well-coordinated funding and lobbying effort, whereas projects that deliver results on only a shoestring budget might not have enough people working on them to get any funding at all.
I'm working at the interface between neuroscience and algorithm theory, and I've already made some very interesting discoveries using borrowed time/funding, but I have trouble shopping my ideas to either pure neuroscience/medical funding agencies (who don't understand the math) or to computer science funding agencies (who don't appreciate the biology). Both sides seem generally excited and encouraging, but neither is willing to fund my future research, since (despite a promising track record) I'm out of the expertise of anyone out there.
My question is, are we doomed to a future dominated by big science projects working in entrenched specialties on the least-efficient, longest-term, too-big-to-fail science investigations out there? If not, how do we promote efficient, small-scale, interdisciplinary project funding?
OPERA has just found that either neutrinos travel 0.03% faster than photons we've measured, or their equipment has an unknown systematic error. Assuming there's no equipment error, I would find it more palatable to assume that light around Earth travels a bit below c and that neutrinos travel closer to c. What we think of as vacuum could really be a medium with refractive index 1.0003, perhaps due to a uniform background of weakly-interacting particles (maybe even dark matter) that affect photons but not neutrinos.
I have a physics undergrad degree; if there's someone here with better qualifications, would you care to weigh in on the idea that c could be 0.03% faster than the speed of light we measure on Earth?
From TFA: “We should have a result in 4-6 months as the data is already taken. We just have to measure some of our delays more carefully,” - Jenny Thomas.
MINOS was already repeating their measurements, but CERN got the jump on them. It's anyone's guess too whether there was a back channel of information from OPERA to MINOS that might have tipped them off and encouraged them to start taking data early. With so many people involved, you almost have to assume that preliminary findings migrate across the Atlantic pretty quickly.
Slashdot Mirror
In fact, I'd argue that every step towards a total understanding of our universe, no matter how small the step, is worth virtually any cost placed on it.
I agree with you 100%, but my application of this sentiment differs from yours. It's a shame when only a few dozen bits are discovered when the same effort could have lead to enormous gains in other fields. That's why I encourage scientists away from particle physics and into other areas like biophysics, nonlinear physics, fluid dynamics, bioengineering, neuroscience, machine intelligence and applied mathematics.
The only way the LHC makes sense is if you believe one bit of particle physics knowledge is worth millions of times more than one bit of neuroscience knowledge, since there might be a million to one ratio of understanding per effort spent. By your signature, it looks like you might still think that particle physics knowledge really is a million times more important than knowledge in any other field. Different strokes for different folks, I guess.
From TFS:
'Either would be a major advance in our exploration of nature, bringing us closer to understanding how the fundamental particles acquire their mass, and marking the beginning of a new chapter in particle physics.'
I can't help but point out that knowing if the Higgs exists will increase our information about the universe by a maximum of 1 bit. (Knowing its mass and decay modes probably would give us more like a dozen or two bits of information - more than 1 bit but still not much.)
Particle physics is great, and doing it carefully *does* increase our knowledge of the world, but only by the tiniest of margins. Imagine if all those thousands of super-bright minds had been focused on some other task for decades? What kind of magic tech would we have by now? The ratio of opportunity cost to benefit is sky high.
Let me chime in with a zoom-out perspective.
Physics is using math to predict what matter will do in certain circumstances. (I find that pretty mind-blowing - that you can *calculate* what will happen to *stuff* if the system is simple enough. Too bad the calculation approach didn't work out for me so well in the girlfriend department in high school - another story.)
Anyway, the math behind how positive and negative charges attract is the same as the math behind how masses attract: they're both "inverse square laws." Three times the distance, one-ninth the force, since 3 squared is nine.
That means that the motion of a charged water droplet around the needle will be the same type of motion as orbiting, which is why it looks just like gravity. The math is the same, so the motion is the same.
There's been some really promising work in the direction of OCR-like problems lately. Here's an algorithm that can efficiently learn a small dictionary of symbols (like letters) and decompose a signal into elements that fit within this "low-rank" dictionary plus sparse noise (bugs squashed on the text?) plus Gaussian noise: https://sites.google.com/site/godecomposition/.
It's not literally magical, but it's super-duper awesome (an no, I'm not an author of this one) and it should contribute to the minor revolution in signal processing (compressed sensing & low-rank matrix completion) that's been gaining momentum since about 2005. If our machines can learn features efficiently and robustly from natural images, many industries are in for a wild shake-up. More on this minor revolution is available at http://nuit-blanche.blogspot.com/.
These algorithms are part of the reason why self-driving cars are starting to work, and I have the excited feeling like we're on the cusp (read, next ten years or so) of a sea change in our ability to have machines able to understand and interact with the physical world with a dash of common sense.
Dear afabbro,
You are largely correct. Most software has not sped up much since the 1970s, and it could even be argued that developers write such sloppy code these days that even our improved compilers can't compensate, especially in applications where performance is no longer critical.
On the other hand, since about 2006 there have been some tremendous advances in algorithms. One optimization problem I work on, Basis Pursuit Denoising http://en.wikipedia.org/wiki/Basis_pursuit_denoising, has had on the order of a 10-fold increase in real-world speed on constant hardware every year for the past 5 years (see http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=5940245 for my contribution).
These advances are not just academic games; they are actually worth doing. They could eventually lead to computers with sensory processing routines that have a mote of common sense to them, able to perform some real-world tasks we currently need humans for.
While I agree that by and large, most software is getting fat and lazy, there are a few problems where today's algorithms on 2002 hardware mop the floor with 2002 algorithms on today's hardware.
Best,
LeDopore
There's a lot of talk as to what you should do while an after the prof is speaking, but so far very little has been said about what to do *before* the professor speaks it. During my Physics undergrad, I would challenge myself to try to derive results and formulas before the prof finished. I was often wrong, and I usually had to have my notes at least nudged along at least a few times per lecture, but trying to derive on the fly is an awesome way to learn something. There's nothing quite like figuring out a problem by yourself to have it really gel with your overall understanding.
That's my advice: rather than just trying to learn, as much as possible *do your own thinking* in class and you'll be amazed at how little you have to work later to recall it.
I'm with you on this one, Russ1642.
Are you saying patent royalties are the only expense when it comes to new technology ?
No, but developing one SDR that works for all phones in 50 countries without worrying about patent infringement certainly sounds like a good way of getting a high ROI when investing in a new technology. Of course there's a lot of work and expense, but I think SDRs are still a great way to go, especially since the best ones now (unlike even 2 years ago) perform almost as well as hardware-defined radios.
I grant that it's always possible to do at least a little better when you know the frequencies you'll use at design time than if you have to have a software defined radio.
That said, Caroline Andrews of the lab I worked in (http://molnargroup.ece.cornell.edu/research.html) developed a software-defined radio using a passive mixer that works in the GHz range with only 1 dB worse noise for the same power as you would use with a fixed radio. She also showed how a software defined radio can do impedance matching through the passive mixer. Amazing, possibly game-changing stuff; if you really are a cellphone radio engineer, don't assume that software-defined radios will always suck hard enough not to be a threat.
By the way, on behalf of Slashdot, YOU'RE WELCOME FOR TEACHING YOU HOW TO DESIGN A PHONE!
Not necessarily. This lab from Cornell isn't going to patent their SDR, and it's a pretty sweet implementation: noise performance almost as good and chip area only slightly larger than a single-band ASIC:
http://molnargroup.ece.cornell.edu/research.html
Full disclosure: I worked with these guys, and the radio group is pure genius.
Does it really matter where they're made? The companies that own the intellectual property are the ones making most of the profit. If a company in China charged enough to make a killing on manufacturing, the owners could look to another company to fill the orders instead. Need proof that this actually happens? Look at how Vietnam is stealing manufacturing jobs from China.
China gets a bad rap, and they might deserve it due to poor labor practices, environmental standards and safety policy. Complain about those issues - I'll likely join you. They don't however deserve to be vilified because they're bleeding us dry with their over-priced manufacturing costs - that betrays a fundamental misunderstanding of the free market. If anything, having a place where manufacturing can be done cheaply is actually a good thing.
Case in point: I'm considering starting to manufacture a niche electronics gizmo for neuroscientists. Using a Chinese company to manufacture most of the hardware (but keeping the final steps in-house to maintain secrecy and avoid the possibility of clones appearing) I should be able to get my first revenue after only a $6,000 investment. My gross profit margin will be 400% - the Chinese are working hard for their tiny 20% share of the pie, and I don't begrudge them their pittance, since neither half of this "partnership" would be viable without the other.
"A few hackers, in their spare time, with no documentation about the hardware, and without the software keys theoretically required to obtain full access to it, managed to do what the multinational corporation that designed the phone said was impossible to do. "
Point taken. However, you might be surprised at how little resourcefulness can be found in multinational corporations. The best talent doesn't always find its way there, and sometimes a small number of brilliant individuals can make progress staggeringly faster than a larger number of pretty-good engineers working 9-5 under corporate processes and restrictions.
Your post is full of awesome!
Phase velocity is w / k. Group velocity is (dw)/(dk). If there's no dispersion, you scale k by a constant factor n slightly greater than 1. This slows both phase and group velocity by a factor of n, if w is proportional to k. If light is interacting with dark matter, you're right that it would interact with each particle extremely weakly, so there would have to be a whole lot of them. Also, probably the transitions would be of such high energy that you wouldn't get noticeable dispersion, so phase and group velocity would be equal.
I'm not in a position to comment on the likelihood of densities of dark matter. I'm not even sure how anyone could predict this with confidence, but you seem pretty sure of it. How do you set limits on the density of a particle with unknown properties you haven't observed yet (not facetious - genuinely interested)?
(Near re-post of http://slashdot.org/comments.pl?sid=2507746&cid=37936976)
OPERA shows light travels little bit slower than the fastest objects we've measured. A little while ago we heard that in galaxies far, far away, either the electric charge is larger, Plank's constant is smaller or the speed of light is smaller (http://slashdot.org/comments.pl?sid=2507746). 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 disproved). Light from the 1987A supernova would not be delayed too much relative to the neutrinos because most of the journey was through regions of space with low dark matter density.
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
Thanks for the great answers. Take care!
My father works at a law firm, and they do remote incremental backups over ssh. I don't really expect that anyone is recording all ssh traffic for later cracking, but on the other hand it would be easy to do. Law firms have all sorts of documents, including a few really secret ones that could incriminate clients. Lawyer-client privilege exists for a reason.
In any case, if ssh fails in 20 years, law firms will be screwed. With documents like these, I have to think ssh isn't good enough, since a 10% chance (rough estimate) of losing all your data in 20 years is an unacceptable risk.
High energy physics almost always refers to energy levels far above standard nuclear reactions. Lightning discharge is plasma physics, but the process behind how charges build up is still mysterious. The experiments conducted at CERN will not lead to technological advances you and I will see in this lifetime - indeed siphoning off money and talent to these projects *harms* the advancement of small-scale but useful science. I'm a scientist working on small projects, that's why I'm bitter.
I have nothing against particle physics per se, but the big projects are so inefficient that their funding is inevitable. When a project requires 10,000 human-years to complete, you can bet they have their grant proposals pretty slick, and politicians love to fund big endeavors, especially when pork barrels come into play. Small-scale geeks working in real-world situations that could have an impact on real-world issues have to beg for scraps from the table of big science.
I would be happy to see funding moved from high energy particle physics towards fields that could potentially yield a benefit to humanity. Like, for example, almost any other scientific investigation.
Nothing against you or your friend personally, but we still don't know how charge is built up in clouds to cause lightning. Why is there so much funding to study CP violation/Higgs bosons, etc. when we still don't understand lightning?
No, your plans for galactic empires are pretty safe: the changes in alpha are only on the order of ten parts per million. At most, bond strengths would be different by about that amount in long-ago galaxies (note, probably by now alpha is more uniform everywhere).
Now, if my hypothesis is correct and if we could make an extremely concentrated dark matter beam that could slow down the speed of light tremendously for all objects in its path, it could seriously alter the chemistry of anything it hits. The target's colour would change, chemical bonds could break, etc. How's that for a weapon to keep your imperial galactic subjects in line?
To be clear, I'm not proposing my hypothesis has been sufficiently demonstrated yet to be convincing. It's not even a theory yet, and I don't have the time or training to make it one. Moreover, even if it's correct, dark matter interacts extremely weakly with anything else - that's why it's dark - so making a beam of the stuff would be so difficult it would hardly qualify even as science fiction. Still, it's fun to think about!
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
Hey dude,
Want to reduce scan times? Check out compressed sensing MRI [1]. You should be able to take way fewer scans than thought possible with 20th century math. Regularized reconstructions are the new hotness, but don't take the word of a Slashdot user who says "dude" and "new hotness"; read these fricking things.
[1] M. Lustig, D. Donoho, J. Santos, and J. Pauly, “Compressed sensing MRI,” IEEE Signal Processing Magazine, vol. 25, no. 2, pp. 72–82, 2008.
I've noticed a disturbing trend that as funding levels drop, agencies are receding more to their core areas of study and leaving interdisciplinary scientists high and dry. Furthermore, it seems that there's an inverse relationship between the fund-ability of a project and its efficiency: if a (say) particle physics project is so inefficient it requires 1000 scientists 10 years to get 1 bit of data (like the Top quark discovery) then they're guaranteed to have well-coordinated funding and lobbying effort, whereas projects that deliver results on only a shoestring budget might not have enough people working on them to get any funding at all.
I'm working at the interface between neuroscience and algorithm theory, and I've already made some very interesting discoveries using borrowed time/funding, but I have trouble shopping my ideas to either pure neuroscience/medical funding agencies (who don't understand the math) or to computer science funding agencies (who don't appreciate the biology). Both sides seem generally excited and encouraging, but neither is willing to fund my future research, since (despite a promising track record) I'm out of the expertise of anyone out there.
My question is, are we doomed to a future dominated by big science projects working in entrenched specialties on the least-efficient, longest-term, too-big-to-fail science investigations out there? If not, how do we promote efficient, small-scale, interdisciplinary project funding?
OPERA has just found that either neutrinos travel 0.03% faster than photons we've measured, or their equipment has an unknown systematic error. Assuming there's no equipment error, I would find it more palatable to assume that light around Earth travels a bit below c and that neutrinos travel closer to c. What we think of as vacuum could really be a medium with refractive index 1.0003, perhaps due to a uniform background of weakly-interacting particles (maybe even dark matter) that affect photons but not neutrinos.
I have a physics undergrad degree; if there's someone here with better qualifications, would you care to weigh in on the idea that c could be 0.03% faster than the speed of light we measure on Earth?
From TFA: “We should have a result in 4-6 months as the data is already taken. We just have to measure some of our delays more carefully,” - Jenny Thomas.
MINOS was already repeating their measurements, but CERN got the jump on them. It's anyone's guess too whether there was a back channel of information from OPERA to MINOS that might have tipped them off and encouraged them to start taking data early. With so many people involved, you almost have to assume that preliminary findings migrate across the Atlantic pretty quickly.