Hard Light Productions Forums
Off-Topic Discussion => General Discussion => Topic started by: Herra Tohtori on September 23, 2011, 03:28:52 am
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Stop right there, neutrino scum! Nobody breaks the superluminal barrier on my watch! Pay the CERN a fine or serve your sentence! Your stolen time is now forfeit.
Nature (http://www.nature.com/news/2011/110922/full/news.2011.554.html)
Science (http://news.sciencemag.org/sciencenow/2011/09/neutrinos-travel-faster-than-lig.html)
BBC (http://www.bbc.co.uk/news/science-environment-15017484)
The experiment is called OPERA (Oscillation Project with Emulsion-tRacking Apparatus), and lies 1,400 metres underground in the Gran Sasso National Laboratory in Italy. It is designed to study a beam of neutrinos coming from CERN, Europe's premier high-energy physics laboratory located 730 kilometres away near Geneva, Switzerland. Neutrinos are fundamental particles that are electrically neutral, rarely interact with other matter, and have a vanishingly small mass. But they are all around us — the Sun produces so many neutrinos as a by-product of nuclear reactions that many billions pass through your eye every second.
The 1,800-tonne OPERA detector is a complex array of electronics and photographic emulsion plates, but the new result is simple — the neutrinos are arriving 60 nanoseconds faster than the speed of light allows. "We are shocked," says Antonio Ereditato, a physicist at the University of Bern in Switzerland and OPERA's spokesman.
Ok, this result puzzles me. Why would neutrinos go faster than light but still stay that close to the value of c? Why wouldn't they go faster? Why would the neutrinos travel at constant speed as opposed to different neutrinos going at different speeds?
How would neutrino oscillations affect neutrinos at superluminal speeds?
If neutrinos have mass, does it mean they never travel at subluminal speeds?
Are they tachyons?
Do they break causality? (short and easy answer - no)
How the hell do these guys reliably detect the transmitted neutrinos when they regularly travel through matter without so much as a single interaction? There's +700 km of stone between the two locations, what makes their instruments capable of reliably detecting the neutrino stream...?
Could this system be used in communication through the Earth (problem: Transmission station requires a particle accelerator and receiver apparatus likely also has huge mass just to ensure reception of a few neutrinos of the beam, and would likely be prone to noise from other neutrinos passing through).
Interesting questions, and I'm eagerly expecting the answers...
However, I suspect there is a systematic error of some kind in the experiment that they just haven't figured out yet. Specifically I would think the error is related to problems in ensuring simultaneity between two locations. How do they ensure that the time measurement between transmission and reception are accurate? Not knowing any details of the experimental set up, can't say anything about that.
Regardless, this is most intriguing and I hope that the light barrier proves not to be the unbreakable ideal it has been assumed to be.
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60 nanoseconds? That can't be right, it's an enormous amount of time in these scales. For now, I'd assume some error in the experiment itself. But if it's not an error, then what? Perhaps gravity is the cause (if there was something in the Earth core that would "compress" space much more than we assume, then perhaps this could influence neutrinos), or maybe FTL is really possible? For sure, this is very interesting.
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My first assumption would be a timing or computer sync issue, but they said they stated
"We wanted to find a mistake - trivial mistakes, more complicated mistakes, or nasty effects - and we didn't," he told BBC News.
so I assume that they have been accounted for, the only possibility that I can think of that dosn't involve breaking c is that the experiment was looking for something unrelated so there might be an error they cant detect. It would be interesting to see if someone can repeat the results in a dedicated experiment.
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The problem with neutrinos is that there aren't many other ways to do anything with them than the way OPERA works. These things were first "invented" as a way to explain missing mass in radioactive decay (IIRC) and not actually found until much later. They're almost completely intangible, weak nuclear force is, unfortunately, quite weak, so is (in these scales) gravity, with the added difficulty of it having infinite range and coming from every single thing in the universe. In short, measuring anything regarding neutrinos is extremally difficult compared to other particles.
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The margin for error on this test was stated at +- 10 nanoseconds. Do Nutrinsos have mass?
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The margin for error on this test was stated at +- 10 nanoseconds. Do Nutrinsos have mass?
Neutrinos have a very small, but nonzero mass
http://en.wikipedia.org/wiki/Neutrino
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60 nanoseconds? That can't be right, it's an enormous amount of time in these scales. For now, I'd assume some error in the experiment itself. But if it's not an error, then what? Perhaps gravity is the cause (if there was something in the Earth core that would "compress" space much more than we assume, then perhaps this could influence neutrinos), or maybe FTL is really possible? For sure, this is very interesting.
I was thinking that mayhap gravity field is stronger at CERN location than on Gran Sasso, which would mean atomic clocks run faster on the recipient's end due to time dilatation (similar problem affected the GPS satellites when they were first put on orbit).
However, in an analysis of the required effect, the difference would need to be 60 nanoseconds in the time it takes for the neutrinos to get to their destination (assuming that the TRANSMIT TIME has been successfully synchronized in both locations and is accurate) - the total travel time for light would be 2,435,017.89 nanoseconds, and 2,434,957.89 for these neutrinos, or 2.435 milliseconds.
That means, for every 31,556,926 seconds that passes in a year at San Grasso, 31,557,703.596839672656537956644 seconds would pass at CERN. That's a time difference of a whopping 777.59684 seconds during a year - that's almost 13 minutes! There's no way that can be right! It would have been noticed a million times already, so I think that can be cast out of the possible reasons.
The second thing I was thinking was local variation of the fine structure constant that could vary the speed at which atomic clocks work at CERN and Gran Sasso, but again this would be something that definitely would have been noticed, and a variation of phi at such local concentration would be unprecedented (there have been speculation of FSC being a variable on cosmological scale rather than constant, but different on one location of a planet to another? No way.)
Those were the two "exotic" possibilities that came to mind first, bypassing all the myriads of systematic error resulting from the test rig itself.
Someone at Nature.com posted an interesting thing. Apparently, the speed of neutrinos is measured as 299,799,846 m/s (within rough margin of error) while speed of light is known as 299,792,458 m/s. That corresponds to velocity differential of about 7,388 m/s. Apparently at about sea level, orbital velocity around Earth would be about 7900 m/s which isn't exactly the same, but in the same ballpark of meaningful numbers.
Now that is probably just chance, but it got me thinking - maybe neutrinos travel straight, ignoring gravity (which would make them truly only affected by the weak interaction!), while the "light path" would be curved by gravity and therefore longer by a slight margin... :nervous:*
Which is a concept that sort of buggers everything we know about light moving along geodesic lines in space-time, and light traveling the shortest path between two spots in space... :shaking:
It would also suggest that gravity indeed is a quantum phenomenon with a gauge boson (we can call it a graviton, or Higgs' boson maybe) rather than space-time curvature being the actual cause for gravity (albeit a very useful model in macrogravity scale).
The neutrino mass speculation is based on the observation of neutrino oscillations - a habit of neutrinos that they can change into each other while traveling. A massless particle would not be capable of experiencing such changes as the time for a massless, light-speed particle would be locked and invariable in its own reference frame (life-time = 0, travelled distance = 0 from, say, photon's perspective).
Monkey wrenches
monkey wrenches everywhere
*Yes I know, Earth's gravity is weak and wouldn't curve a light beam all that much at 730 km distance at sea level - however it WOULD be slightly curved and a "straight" line between A and B would be technically a bit shorter. CBA to actually calculate how much shorter though. :p
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some ideas come to mind. propagation delays in semiconductors, floating point errors, gravitational variance, imprecise distance measurement, the list goes on and on. either something broke or they got to rewrite all the physics textbooks.
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the thing that grabs my attention about this though is it has the CERN "brand name" attached to it, this is not Austin County Community Collage, this is mother effing CERN, if it's some thing simple then I would have hoped they would have figured it out within three years, but they are human so they will make mistakes every once in a while. so the easiest (and most likely) answer is 'they ****ed up' but these are people you would not expect to **** up on this scale.
also, it has been noted that light can move faster through a medium, maybe neutrinos can too? maybe they interact more than we thought, but it usually is in a harder to detect way?
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the thing that grabs my attention about this though is it has the CERN "brand name" attached to it, this is not Austin County Community Collage, this is mother effing CERN, if it's some thing simple then I would have hoped they would have figured it out within three years, but they are human so they will make mistakes every once in a while. so the easiest (and most likely) answer is 'they ****ed up' but these are people you would not expect to **** up on this scale.
also, it has been noted that light can move faster through a medium, maybe neutrinos can too? maybe they interact more than we thought, but it usually is in a harder to detect way?
The media does have tendencies to blow things like this way out of proportion. Unless this gets verified and repeated I'm assuming it was some kind of glitch.
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Oh good, I finally found the publication thanks to the BBC news link! Thanks Herra!
http://static.arxiv.org/pdf/1109.4897.pdf
Guess I'll have to retract what I said in the other thread about them not posting the methods/data. Looking through it now, still not convinced but it does so far look like they've covered most of the obvious angles.
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Light's top speed is in vacuum and all photons always travel through vacuum.
In transparent medium, photons interact with the matter they travel through and thus their apparent speed (or, the collective wavefront speed) measurably decreases while the wavefront itself still stays intact. In non-transparent mediums, the light is diffuded (the wavefront doesn't stay intact and light scatters about).
Light does not travel faster than c in medium, but particles can travel faster than the light's wavefront speed in medium, which causes Cherenkov radiation.
Like said though, I do expect it to be an error somewhere along the line, as it's the more likely explanation of the two options. However... it does pose interesting questions if it actually happens to be legit observation with no other explanation or mitigating factors.
Also, CERN is not in the habit of releasing sensationalist statements, they are very much in the frontline of hard and arduous science making. They do check things through before releasing their results.
So, what we'll need now is a dedicated test rig to specifically test neutrino speeds, preferably with longer range and with higher pulse yields.
In fact, I suggest construction of World Area Neutrino Telescope (or WANT for short). It would consist of several neutrino observatories built all over the globe and connected via simultaneity-calibrated network that keeps the instruments in the same time. This would enable us to observe neutrino pulses with a lot more information of them than before - mainly, directional analysis, as well as directly observing the speed at which a neutrino front passes through the Earth.
Screw making pitiful neutrino pulses in a particle accelerator - we can use the neutrino pulses from supernovae, with multiple observatories (minimum of four, but as much as possible would be better) we can already determine the direction of the pulse with fairly good accuracy as well as determine the time differential of the pulse hitting the instruments at different areas of Earth.
Who's with me? Shouldn't be too difficult. Just make big water tanks all over the world in the bedrock with high sensitivity flash detectors lining their inner walls. :p
Who knows, maybe with enough info and interferometric reconstruction of the data, we could even gauge the Sun's neutrino stream more accurately than before.
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Light's top speed is in vacuum and all photons always travel through vacuum.
In transparent medium, photons interact with the matter they travel through and thus their apparent speed (or, the collective wavefront speed) measurably decreases while the wavefront itself still stays intact. In non-transparent mediums, the light is diffuded (the wavefront doesn't stay intact and light scatters about).
Light does not travel faster than c in medium, but particles can travel faster than the light's wavefront speed in medium, which causes Cherenkov radiation.
Like said though, I do expect it to be an error somewhere along the line, as it's the more likely explanation of the two options. However... it does pose interesting questions if it actually happens to be legit observation with no other explanation or mitigating factors.
Also, CERN is not in the habit of releasing sensationalist statements, they are very much in the frontline of hard and arduous science making. They do check things through before releasing their results.
So, what we'll need now is a dedicated test rig to specifically test neutrino speeds, preferably with longer range and with higher pulse yields.
In fact, I suggest construction of World Area Neutrino Telescope (or WANT for short). It would consist of several neutrino observatories built all over the globe and connected via simultaneity-calibrated network that keeps the instruments in the same time. This would enable us to observe neutrino pulses with a lot more information of them than before - mainly, directional analysis, as well as directly observing the speed at which a neutrino front passes through the Earth.
Screw making pitiful neutrino pulses in a particle accelerator - we can use the neutrino pulses from supernovae, with multiple observatories (minimum of four, but as much as possible would be better) we can already determine the direction of the pulse with fairly good accuracy as well as determine the time differential of the pulse hitting the instruments at different areas of Earth.
Who's with me? Shouldn't be too difficult. Just make big water tanks all over the world in the bedrock with high sensitivity flash detectors lining their inner walls. :p
Who knows, maybe with enough info and interferometric reconstruction of the data, we could even gauge the Sun's neutrino stream more accurately than before.
I was thinking along similar lines, but unfortunately I dont have a couple of billion in my back pocket to fund it
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there might be something specific about this experiment, they were trying to figure out why neutrinos change type, maybe the specific type of neutrinos they were making or how they were making them did something, maybe it isn't a simple function of energy so even if it comes from a supernova it wouldn't show the same effect, maybe you need to have 'fresh' neutrinos that pass through relatively dense solid matter for this effect to happen.
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I recall reading yesterday that the group is hedging their results and practically begging others to attempt to replicate their results. It'll be crazy if it's not an experimental design failure and actually a true result.
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I guess it would have been noticed if the speed of light had suddenly changed by ~7000 m/s... :nervous:
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It would certainly have made the guy whose spends each day shooting the moon with a laser to find its distance go WTF. :lol:
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Rest assured CERN does **** things up. A couple of my colleagues have been working there, and based on their anecdotes, CERN has caused considerable repair bills to the nations funding it. Despite of that, they don't usually release preliminary results.
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Rest assured CERN does **** things up. A couple of my colleagues have been working there, and based on their anecdotes, CERN has caused considerable repair bills to the nations funding it. Despite of that, they don't usually release preliminary results.
Do you refer to the helium incident (http://tvtropes.org/pmwiki/pmwiki.php/Main/LetUsNeverSpeakOfThisAgain) or some other stuff (http://tvtropes.org/pmwiki/pmwiki.php/Main/NoodleIncident)?
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I'm extremely annoyed at how badly the press has blown this out of proportion. It basically amounts to the research group saying "hey guys, our results don't make any sense. We can't figure out why, so we're opening this up to the wider community."
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Did you expect anything else from the press? It's the press, of course they'll blow it out of proportion.
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On a light-er (har har) note, Twitter has some hilarious comments on #mundaneneutrinosexplanations: http://twitter.com/?lang=en&logged_out=1#!/search/%23mundaneneutrinoexplanations
My favorite so far:
physicsdavid David Harris
Due to austerity measures the speed of light has been reduced #mundaneneutrinoexplanations
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Do you refer to the helium incident or some other stuff?
Few people know how extensive the damage of the helium incident was. But that's not all of it.
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I for one blame ponies.
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(http://28.media.tumblr.com/tumblr_lg6iplPpeh1qfewofo1_500.png)
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haven't certain particles been shown to teleport under certain conditions? perhaps this happens as a result of the neutrinos changing type.
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neutrons neutrinos changing type are soft particles.
[edit]by neutron I mean neutrino[/edit]
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meh, got my particles mixed up there.
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I got hard particles if you catch my refraction
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Ironically, neutrons do change type. Free neutrons' half-life is 881.5±1.5 seconds, and they decay into proton, electron, and electron's antineutrino.
Of course, neutrons in unstable nuclei also exhibit this behaviour, in which case it's called beta- decay. The half-life of neutrons in nuclei is longer, though, due to nuclear interactions.
...although you shouldn't be too quick to assume that a neutron is made of an electron and a proton. It doesn't work that way - a neutron is made of three quarks of up, down, down variety, while a proton consists of up, up, down quarks in the standard model of particle physics.
...and just to confuse things, a proton in unstable atomic nucleus can also decay into a neutron, a positron, and electron's neutrino. This is called beta+ decay.
Like before, you shouldn't think that a proton is made of a neutron and a positron. :p
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Edit: Misread something.
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Like before, you shouldn't think that a proton is made of a neutron and a positron.
Are you positive about that? /badpun
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Something a friend of mine said on this matter, in another forum:
consider the following:
1) Based on currently accepted theories, c is the universal speed limit.
2) Photons travel at c in a perfect vacuum.
3) Photons travel at less than c in any medium other than a perfect vacuum.
4) The observations did not occur in a perfect vacuum.
5) Photons interact with matter more frequently than Neutrinos.
6) More interaction leads to greater friction.
7) If the Neutrinos have sufficient energy, the lower friction they have compared to photons could result in the Neutrinos outrunning the photons.
8) Ignoring Photonic friction can lead to an inaccurate measure of c.
9) 7 and 8 combined can lead to the appearance that the Neutrinos have exceeded c when the sub-c photons have actually been sufficiently slowed down.
Just one possible explanation that maintains current understanding of the universe.
I can't *really* comment because I don't go looking up this kind of stuff for fun. :S
It's mostly beyond me.
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It's not a question of the neutrino's arriving before the photons - the experiment is 720 kms away from the source, so the photons are never going to make it - curvature of the earth and all that. It's a question of the neutrinos arriving before the photons possibly could, even at their vacuum speed.
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Could it be explained by photon having a very small mass and not actually travelling at c (meaning the true relativistic limit)? The mass of a neutrino would simply be even lower than that of a photon. No particle (maybe except hypothetical gravitons) would thus be massless. I wonder what would that mean for the Higgs mechanism?
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Not likely -- photons are electromagnetic oscillations and thus have no rest-mass associated with them. If they did have mass, then they would impart more momentum to whatever objects they impacted on, and we should be able to measure this.
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but it could be an indication of negative mass ;7
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but it could be an indication of negative mass ;7
Not negative. Imaginary. :nervous:
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could be both, right now we have no idea why this is happening, could be they mis-measured the detectors position by 60 feet, could be there is an alien time ship buried in the earth's lower crust in just the right place to effect the particles.
honestly, I have a feeling that the fact that they were passing through the earth immediately after being created might have something to do with it, if this doesn't just turn out to be a systematic error, [Eeyore]which it probably will :([/Eeyore].
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What would be the implications or issues if the speed of neutrinos were actually the new maximum speed?
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What would be the implications or issues if the speed of neutrinos were actually the new maximum speed?
Relativity was wrong
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Relativity was wrong
It wouldn't just need a footnote? "Except for neutrinos, which go about 60ms faster?"
Or you replace all instances of c with whatever letter they decide on for speed of neutrinos?
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It would require an explanation for why the speed of electromagnetic radiation is always constant despite not traveling at the maximum speed. If the maximum possible speed were indeed faster then you'd expect to be able to see variability in light's speed depending on the relative motion with respect to the source, but we have never observed that.
It'd be a really awkward situation if this ends up getting verified.
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More like a really INTERESTING situation, amirite?
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The barkeep says 'We don't serve faster-than-light particles in here'. A neutrino walks into a bar.
-- Too many people on slashdot.
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Light is how we define time. So travelling faster then light allows us to travel faster then time. Or something.
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Light is how we define time. So travelling faster then light allows us to travel faster then time. Or something.
No, light is how we define distance.
Time is defined through the oscillations of the ground energy state of Caesium-133 atom (one second is exactly the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom, as quoted from Wikipedia).
Now that we know the duration of a second, we can measure how far a photon goes in one second, and that is defined as exactly 299,792,458 seconds.
Therefore one metre is defined as the distance that a photon travels in 1/299792458 seconds, which corresponds to 30.663319 periods of ground state oscillation of Ce-133 atom.
Now, special relativity assumes that the speed of light is invariable (same for every observer) and therefore should be the speed of causality in the universe.
If there are faster than light particles, then clearly light's speed can't be invariable to them as they would observe photons moving backwards compared to our observation of them.
Weird things start happening in special relativity with superluminal objects, and that's an understatement of the century. Lorentz transformations obviously fail when c=0, but mathematically you can get them working when c>0, you just need to use imaginary numbers for that because you need to take square roots out of negative numbers; what implications this would have for such particles in reality are something I don't really even want to think of.
Regardless, faster than light particles would be very problematic for the base assumptions of special relativity, as it would mean time is not as relative as we have thought.
Considering all the previous observations that have directly supported relativity, it's at this moment unlikely that this neutrino anomaly will prove to be anything but a glitch in the matrix. prove to be anything but a glitch in the matrix.
Now, personally I would gladly welcome any observation that breaches the iron grip of relativity on all known physics, because that would perhaps mean barriers such as light speed are not as unbreakable as have been assumed. And I really want us to get away from Earth at one point... preferably before it's rendered unsuitable for human occupation, either by our own actions or something outside our control such as comet or asteroid impact. Or, at the latest, the Sun's expansion.
Need to get that FTL working, you know... :p
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what exactly happens when a neutrino hits another particle? does it kinda phase on though? or does it do some kinda teleport magic? im kinda curious if space actually exists within a particle (assuming these particles have dimension). could it be possible that space does not exist where ever a particle may be? if you assume that it does not, and considering that what we perceive is solid rock is mostly empty space, with an occasional particle in it, so when the neutrino actually hits some other particle, i'm curious if this doesn't result in the neutrino instantly moving from once side of that particle to the other, without actually moving through space. so as this particle moves along, each time it hits something it might jump a very short distance to cross the particle. then these (tiny) distances add up to reduce the length of travel and shave a few nanoseconds off the particles journey at velocity c. i thought about this way back when i used to smoke a lot of weed, but wrote it off as a stupid idea. a product of alaskan dope and a documentry on string theory.
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Light is how we define time. So travelling faster then light allows us to travel faster then time. Or something.
This gave me an idea for a physicists clock
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There's no such thing as "collision" in quantum mechanics, so the question isn't really relevant.
In the standard model, particles are typically dimensionless (although their wave function of probable existence in points of space can have variable spread based on the properties of the particle, making the particle have an apparent "size").
Also, you have to remember that in quantum level there is no such thing as "solid". Every interaction happens via gauge bosons. For example, in macroscopic world a football doesn't phase through your foot because the surfaces meet each other; on quantum level this means a LOT of electromagnetic interactions that simply don't apply to single particles in quite the same way.
So, no, dimensionless particles do not "collide" or "phase through" each other. However when they get close enough to each other, they can interact with each other, and usually do. An example would be of two deuterium nuclei approaching each other. As they approach each other they experience a repulsive force through electromagnetic interaction - that is, their electric charges repel each other through virtual photons (I am not making this up).
If their initial velocity is high enough, they can get close enough to each other that the so-called strong interaction becomes more powerful than the Coulomb force. Strong interaction or strong nuclear force is transmitted via particles called gluons and it is by far the most powerful force of nature in the scale of atomic nucleus. When the strong interaction starts to pull the particles together, they fuse to form one combined particle - in this case it would be an alpha particle, or Helium-4 nucleus consisting of two protons and two neutrons, held together by the strong nuclear force.
In the context you speak of, particles never collide with each other; only their spheres of influence get close enough to each other that noticeable interactions are transmitted through them, and interesting things consequently happen.
Of course, there is the Pauli exclusion rule that posits that no two fermions can occupy the same quantum state at same space and time. In case you wonder what fermions are, they are particles that follow the Fermi-Dirac statistics; the other type of particles known are the bosons which deliver the interactions between particles. Neutrinos are, at the moment, classified as fermions, and more specifically leptons.
Neutrinos are a curious breed of particles because the only known way for them to interact with anything is through so called weak interaction, and more specifically since neutrinos have neutral electric charge, the interaction is transmitted by the so-called Z-boson (Z-bosons are have neutral electric charge, while W+ and W- -bosons have electric charge).
The probability of a neutrino interacting with a more typical particle such as electron (or proton or neutron for that matter) is rather unlikely, so you need a lot of neutrinos passing through your detector (which is not a problem at all since those things are everywhere) and a BIG detector with good way to observe the very weak flashes of light caused by neutrino interactions with matter.
You also need a way to exclude other possible sources of flashes of light such as cosmic radiation, so the best place for neutrino detector is deep underground.
Deathfun... be welcome to try and invent new and better ways to measure time, but beware of redundant definitions sneaking up on you. :p
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IIRC, you can measure time using distance units (physicists sometimes do that). This simplifies a lot of calculations, and if you take a unit in which c=1, Lorentz transformation (and relativistic calculations in general) suddenly becomes really simple. In one book I read (I can't recall the title), the author even proven that you could measuring energy (and of course, mass) with that very same unit. Perhaps physicists working on relativity also do that (outside of that book, I never really heard about that though, so it's possible that it's impractical).
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IIRC, you can measure time using distance units (physicists sometimes do that). This simplifies a lot of calculations, and if you take a unit in which c=1, Lorentz transformation (and relativistic calculations in general) suddenly becomes really simple. In one book I read (I can't recall the title), the author even proven that you could measuring energy (and of course, mass) with that very same unit. Perhaps physicists working on relativity also do that (outside of that book, I never really heard about that though, so it's possible that it's impractical).
That only works if you have a calibrated measuring stick whose length is known...
...and you measure length based on how long a photon travels in an unit of time, so you need a definition for unit of time first to calibrate your measuring equipment.
This doesn't change what is being measured, but you really rather need to take great care to avoid redundant definitions and circular logic.
And I think the book you mention was referring to the use of natural units, which are a way to simplify a lot of equations in, say, special relativity - just substitute c with 1. Same stuff is often done in quantum physics with Planck constant, and there's also a special unit of mass called atomic mass unit (amu, or dalton) that is used in chemistry, defined as one twelwth of the mass of carbon-12 atom in its ground state, and it's approximately the mass of proton or neutron (though not quite), just so that chemists and nuclear physicists could use "1" for the approximate mass of protons and neutrons when dealing with isotope masses.
Heck, particle physicists started using electronvolt as an unit of energy simply because it was a handy way of describing the energy that an electron would get in a particle accelerator when it traveled through one volt electric potential difference; 1000 volt potential would give one electron the energy of 1 keV, etc.
For more information on natural units and what natural constants are used to define them, consult the book of knowledge (http://en.wikipedia.org/wiki/Natural_units).
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I'm pretty sure that this one book specifically brought every value that matters in physics to one unit. Could have been "Hyperspace" by Michio Kaku, but I'm not sure. I'm sure that spacetime can be measured using one unit (heck, I can even quote):
For example, in special relativity space and time are so closely related that it can be useful to not specify whether a variable represents a distance or a time.
I can't find in which book it was, but I think that energy was brought to the same unit by exploiting how it warps spacetime. The author did that mostly to show how neatly equations start to look when such simplifcation is made.
EDIT: I was simply thinking of this: http://en.wikipedia.org/wiki/Natural_units#.22Natural_units.22_.28particle_physics.29
Still didn't checked the book, but I'm sure that for demonstration purposes it used either seconds or meters as a "base" unit instead of eV, but it was mentioned both there and in wiki that any unit will do.
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...it's at this moment unlikely that this neutrino anomaly will prove to be anything but a glitch in the matrix. prove to be anything but a glitch in the matrix.
/me sees what you did thar... ;)
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^ Nice.
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One of my physics prof's just published a critique of the super-luminal neutrino observation, which can be found here on arXiv (http://arxiv.org/abs/1110.0736). Might be an interesting read for the physics-inclined viewers around here. :)
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Whoops... (http://blogs.discovermagazine.com/badastronomy/2011/10/15/followup-ftl-neutrinos-explained-not-so-fast-folks/)
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One of my physics prof's just published a critique of the super-luminal neutrino observation, which can be found here on arXiv (http://arxiv.org/abs/1110.0736). Might be an interesting read for the physics-inclined viewers around here. :)
Good read. There's a typo in one of the headings, though. Neutrino is spelt as nwutrino. :P
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Whoops... (http://blogs.discovermagazine.com/badastronomy/2011/10/15/followup-ftl-neutrinos-explained-not-so-fast-folks/)
Boy would that be embarrassing if neglecting to account for special relativistic effects from the GPS satellites ends up being the explanation for this. :<
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Whoops... (http://blogs.discovermagazine.com/badastronomy/2011/10/15/followup-ftl-neutrinos-explained-not-so-fast-folks/)
note that he's not sure, it could be that's already been accounted for when they said they "accounted for all relativistic effects" and even our link friend says so.
jury's out until the guys that did this note it.
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http://www.bbc.co.uk/news/science-environment-15791236
Tests re-run and results confirmed, the Neutrinos appear to be breaking the speed the light.
This could get interesting.
<2012>"The Neutrinos.... they're speeding!'</2012>
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Ah! so you are following this too?
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an interesting development lets hope these are the moments that allow future generations to achieve some form of FTL.
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Ah! so you are following this too?
I find it interesting, I'm not certain how significant it is in the larger scheme of things, the implications might actually be echoing louder than the impact it actually has on physics, but only time will answer that, but it is a serious shot across the bow of Relativity as it stands. And it's always exciting when a basic scientific precept gets a bit of an airing, it does it some good :)
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Well that could mean many things however we are quite still far from the idea of FTL, aren't we?
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Well, not whilst this is only operating at a neutrino level, I would have thought. Whether such a trick could be applied to larger objects is both unknown and, on first glance, probably unlikely. What we are seeing here, most likely, is a quantum level effect, and quantum, like biology, doesn't scale up to macro sizes very well. Make an exact duplicate of a pigeon, only ten times bigger, and it will break its legs every time it lands. I think you'll come across a similar type of problem with this.
Edit: At the end of the day, it depends how fundamental the flaw is in the original theories I suppose (assuming this neutrino event stands up to peer-review), but I still consider relativity to be a pretty sound theory, it's probably a case of a slight alteration than a complete re-write, and it all depends on what alteration it involves as to what impact it has.
Edit 2 : I suppose the next question Physicists will be asking themselves is 'does the neutrino actually occupy real-space for the entire journey, or is there some kind distant relative to electron state-jumping going on here?' Since moving the neutrino out of the 'Newtonian universe' would allow it to do this without actually breaking any relativity laws whatsoever.
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Edit 2 : I suppose the next question Physicists will be asking themselves is 'does the neutrino actually occupy real-space for the entire journey, or is there some kind distant relative to electron state-jumping going on here?' Since moving the neutrino out of the 'Newtonian universe' would allow it to do this without actually breaking any relativity laws whatsoever.
Is this sort of like a subspace idea here where the neutrino / electron enters a different dimension, or is it the neutrino / electron itself that changes its properties?
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I think it would be more a case of ignoring certain properties of space time, in the same way as an electron appears to jump states without traversing 'time' in any detectable way. I really am a layman with regards to this, but I remember Richard Feynman putting forward a thought-proposition that seemed intriuging. He basically said that it is not beyond the realms of possibility in quantum physics that every single electron in the universe is the same electron just jittering back and forth through all of time and space. It wasn't really put forward as a plausible theory as such, more a demonstration of the kind of wierd possibilities that have to be included when dealing with stuff at a quantum level.
Edit: As a thought, what this might have implications for in the future is possibly more along the lines of FTL computing rather than travel. If these sort of quantum effects could be utilised to carry data, the possibiilties are quite formidable.
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Here's to hope that this isn't a measurement error.
I'm starting to accept the possibility that they might have discovered a new phenomenon. Which would be good news, especially from the side of experimental physics.
However, I still do detect some amount of sceptism about this.
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However, I still do detect some amount of sceptism about this.
This is science. And a rather revolutionary discovery. I would be rather disappointed if there wasn't a LOT of skepticism.
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I think it would be more a case of ignoring certain properties of space time, in the same way as an electron appears to jump states without traversing 'time' in any detectable way. I really am a layman with regards to this, but I remember Richard Feynman putting forward a thought-proposition that seemed intriuging. He basically said that it is not beyond the realms of possibility in quantum physics that every single electron in the universe is the same electron just jittering back and forth through all of time and space. It wasn't really put forward as a plausible theory as such, more a demonstration of the kind of wierd possibilities that have to be included when dealing with stuff at a quantum level.
That would be more like infinite improbability wouldn't it? Because you cannot be certain at any exact moment where that one electron is.
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this is big because it disproves the whole 'causality' connection to the speed of light. in other words it does not break the most basic premises of what we know as reality and time to move faster than the speed of light.
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well flipside, I believe it was once aknowledged that the transport of even information at FTL speeds was as seemingly unfeasable as transporting matter at FTL speeds! That means we are quite far off!
However if one is achieved, then I believe the other would be regarded as a much more credible possibility.
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The best explanation for a hard limit on speed is still derived from Conways Game of Live imho... where c = 1 square per turn.
Considering that we can already model computer circuitry in Conways game there is currently no know reason why we wouldn't, in theory, be able to model AI and ultimately brain activity (using billions over billions over billions over billions of squares ;) ) ... and heh, those poor sods seriously would have little chance to ever guess what system their universe is based on as it would literally be impossible to verify the nature of the system while yourself being a) within the system and b) complex enough to ponder the quesiton ;)
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well flipside, I believe it was once aknowledged that the transport of even information at FTL speeds was as seemingly unfeasable as transporting matter at FTL speeds! That means we are quite far off!
However if one is achieved, then I believe the other would be regarded as a much more credible possibility.
Well, thing is, there are some breakthroughs with stuff like Quantum computing that are already making use of things like entanglement etc. Obviously, the usefulness of this neutrino effect, if it is confirmed, is still unknown, but I think it would be far more likely to move information around at FTL speeds than matter. After all, you can encode information using something like amplitude or frequency of signal within something that already exists and has the neccessary properties (that's, pretty much, how digital stuff works). That may be impossible in this case, but I think it's a far more likely outcome for usage. A simple stream of 'neutrino/no neutrino' could be encoded as a binary signal once some kind of synchronization had been figured out. It uses the same theory as current tech, but just uses neutrinos instead of electrons.
I'll once again re-iterate that I don't know if such a system would be possible, heck, we don't even know for certain if this effect is real yet or how or why it comes into being if it is, let alone investigated possible applications, but we shall have to wait and see.
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:bump:
New news on the alleged FTL neutrinos. Looks very likely that experimental error is to blame after all. More tests expected in May.
The two problems the team has identified would have opposing effects on the apparent speed.
On the one hand, the team said there is a problem in the "oscillator" that provides a ticking clock to the experiment in the intervals between the synchronisations of GPS equipment.
This is used to provide start and stop times for the measurement as well as precise distance information.
That problem would increase the measured time of the neutrinos' flight, in turn reducing the surprising faster-than-light effect.
But the team also said they found a problem in the optical fibre connection between the GPS signal and the experiment's main clock.
In contrast, the team said that effect would increase the neutrinos' apparent speed.
....
Given that the opposing effects only seem to muddy the waters further on whether neutrinos can exceed the "universal speed limit", only more experiments will put the matter to rest.
For its part, the Opera team said in a statement: "While continuing our investigations, in order to unambiguously quantify the effect on the observed result, the collaboration is looking forward to performing a new measurement of the neutrino velocity as soon as a new bunched beam will be available in 2012."
http://www.bbc.co.uk/news/science-environment-17139635
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Damn! It was so exciting...
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http://www.bbc.co.uk/news/science-environment-17364682
Excitement over, looks like that under the new conditions, they stick to the speed limit.
Ah well, it was fun while it lasted :)
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That would be more like infinite improbability wouldn't it?
Is it bad that the first thing I thought about after reading those words was this...
(http://images.wikia.com/hitchhikers/images/9/9f/Heartofgold_exterior1.jpg)
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No, no at all because that was the exact thing he was (quite obviously) referencing. :wtf:
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No, no at all because that was the exact thing he was (quite obviously) referencing. :wtf:
(http://www.fmi.ca/uploads/1/DAMN_IT_JIM__cropped_250_pix.jpg) I'm a medical science student not a physicist.