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    Testing OPERA with Nuclear flare: A simple race between anti-neutrinos and photons.
    By Hontas Farmer | November 25th 2011 10:12 AM | 40 comments | Print | E-mail | Track Comments

    If we can produce neutrinos at the same time as photons,then detect which arrives first the question of neutrino speed vs light speed would be settled.    CERN – OPERA measured neutrinos arriving faster than light would have, astronomers have measured neutrinos and light arriving at about the same time from supernovae.  How can we verify the CERN – Opera experiment,reproduce the supernova result, and settle this question once and for all?  We can do this by repurposing one of the most destructive things ever created by the hands of man, a atomic bomb.

    Complication is the mother of all experimental doubt and error, and the OPERA experiment is indeed complicated.  Any experiment which uses a setup largely similar to it will be dogged by the specter of error due to their complexities. 

    OPERA measured neutrinos arriving 60 nanoseconds before they would have if they moved at the speed of light and no faster.

    Supernova SN1987A produced a burst of neutrinos and light.  The neutrinos zipped from the core of the star to the surface without interacting with anything.  This made the neutrinos arrive four minutes faster.  The light would need to bounce around in the star just that long before exiting.  Essentially the light and neutrinos arrived simultaneously.  This is seen by some as a definitive test of vneutrino/vlight.  Others are not so sure.

    A simple race

    The simplest most direct test would be to keep observing supernovae and see if their neutrino pulses arrive way before their light.  The light and neutrinos travel through the same space, along the same path from source to observation.  In essence it is a straight forward race between two particles.  The problem is that some can doubt weather a given neutrino signal is from a particular supernova.  We need more control at the point of production, we need a manmade supernova, we need to use a fusion bomb (or six).   This would produce anti-neutrinos, but that should not affect their speed.  (Using nuclear devices in this way was first proposed by Fred Reines and Clyde Cowan of Los Alamos National Laboratory http://library.lanl.gov/cgi-bin/getfile?25-02.pdf)

    The proposal is technically simple, but politically complicated. 

    1. Step1: Remove the warheads from two minuteman ICBM’s.    
    2. Step2: Mount said warheads on a Delta IV rocket, withwhatever is required to arm them once the probe has escaped from earth orbit,and safely away.   
    3. Step3: The probe should launch individual warheads (usingthe MIRV technology developed for the minute man).  Once the probe is a safe distance away thewarhead will detonate.   
    4. Step4: The existing infrastructure of neutrino detectors canbe used in conjunction with simple telescopes and well known electronics to determinewhich is detected first.  There are threepossible results from step four.    

    • Vneutrino/Vlight>1 Neutrinos do travel faster than light.  
    • Vneutrino/Vlight=1 Neutrinos travel only as fast as light.  
    • Vneutrino/Vlight<1 Neutrinos travel at a lower speed than that of light.   

    This should be done multiple times to give the result some statistical significance.  Three to six times would be most practical because a minuteman three has three MIRVed warheads.

    I defy anyone to find a problem with the physical reasoning. 

    If the neutrinos are detected more than a few nano seconds before the light; then result A has been obtained.  (For the same reason that it takes light longer to exit the core of a star, neutrinos are less interactive than light.)  This would show without any ambiguity that OPERA was right, and neutrinos do travel faster than light.  If neutrinos are as fast as OPERA indicates they should arrive a matter of seconds, not just nanoseconds, before the light.  The distance from these explosions to the earth would be millions of miles.   It would be a very clear signal.

    If results B or C are obtained by this method then OPERA is wrong and we all have to live constrained by the speed of light.

    Why this will probably never be done, politics.

    This will never be done for one reason, politics.  The physics is very clear that this would work as a test of neutrino speed.  The problems come from non-scientific concerns.  Sill valid, just not scientific in nature. 

    The partial test ban treaty has, since the 1960’s, prohibited nuclear weapons testing in space.  That has been interpreted the use of any nuclear devices in space.  It could be argued that this would not be a test of the warheads.  We know they will work, never the less, we would need permission from the other signatories of that treaty.  One would think Russia would not mind having two fewer minutemen pointed at them, but you never know.

    Anti-Nuclear public sentiments, reinforced with some legitimate fear.  A certain segment of the public is afraid any time we use nuclear technology in space.  Notably in the generators of certain space probes such as the latest Mars rover set to launch very soon.   The proposed experiment would use actual nuclear bombs.  Devices designed to blowup and kill millions in the process.  It is not inconceivable that an accident could lead to detonation.  The warheads could arm on the Launchpad and the Delta IV could have a catastrophic failure. The results would be an almost unprecedented catastrophe.

    Getting the political support needed to make this happen would be almost impossible.  I just don’tsee congress and the president ever going along with this, let alone the international community.   There is too much fear around the word nuclear.    The chance of accidental detonation of an unarmed nuclear device is essentially zero. There is a better chance of being killed by lighting than by the described space mission.  Such facts never get in the way of anti-nuclear hysteria.

    Too long; Read This.

    The experiments done to date, or proposed for testing the OPERA result suffer from the same fundamental weakness.  They are physically complicated in many and various ways.  The simplest test would beusing a ready made supernova, a nuclear device.   When these detonate a pulse of neutrinos is released as well as a pulse of light.  We can detect which arrives first the anti-neutrinos or the light and that will give us a simple and definitive answer.  This will likely never be done due to politics, and mostly irrational fear.   So, keep watching the neutrino detectors and the skies for more supernovae.  They are the best most direct test of OPERA’s results.

    Comments

    Why are we always thinking on a large scale when we already have nano technology at our disposal?

    Hfarmer
    If you can think of a way to test this using nanotech more power to you. 
    Science advances as much by mistakes as by plans.
    "I defy anyone to find a problem with the physical reasoning." 

    Supernovae:        ~10 MeV
    CERN:                   ~30 GeV

    Nuclear flare :      ~10 MeV 
     
     


    Hfarmer
    I see no reasoning for why that should make a difference.  

    Here's my reasoning for thinking that should not make a difference. 
    We have been slamming protons and anti protons together at an energy of 1 TEV, just a little down the way from my house, for over a decade.  No superluminal events have been seen at FNAL or any other accelerator. 

    What ever the phenomenon is it cannot depend that much on the specific energy of the particles. If that result is authentic, the cause will prove to be a property of the particles that is not energy dependent.   Neutrinos will prove to be a very different particle from the other quarks and leptons. 

    Science advances as much by mistakes as by plans.
    Halliday
    Hontas:

    While your speculations may well be correct, they are only speculations, at this point (admittedly backed by a great deal of prior particle experience, of course [speaking collectively, and not individually, of course]).

    Just as "Complication is the mother of all experimental doubt and error", so are differences between experiments (and the necessary extrapolation process).  Derek simply pointed out one potential difference (one that has also been brought up in comparing the CERN/OPERA results with supernova results).  Another difference, that has also been brought up before, is electron-neutrinos vs. muon-neutrinos.  One could even question neutrino vs. anti-neutrino differences (such as in CP violation).

    Besides, if the superluminal neutrino results are not due to the neutrinons, so much, but the hadrons that preceded them (that are included in both the timing and distance aspects of the CERN/OPERA experiment), then your proposed experiment could show no effect, and still refute nothing.

    Additionally, if the superluminal neutrino results are due to some very short "jump", a longer baseline will only serve to hide the signal within greater uncertainties.

    Speaking of "jump"-type scenarios, why couldn't such "jumps" be energy dependent?  Couldn't they have some energy threshold (like the photoelectric effect)?  Now, that would be a highly non-linear energy dependence, but would it be impossible?

    While I expect the CERN/OPERA results are from a systematic error (especially once it was revealed that the time clock, on the OPERA side, has only a 50 ns resolution), I'm simply pointing out that if this "anomaly" is real that many otherwise reasonable assumptions and extrapolations simply may not apply.  This is why I called what you said "speculation".

    David
    Hfarmer
    While your speculations may well be correct, they are only speculations, at this point (admittedly backed by a great deal of prior particle experience, of course [speaking collectively, and not individually, of course]).
    Your correct this scenario is at this point just a speculation, an idea thrown into the net to see what holes can be punched in it.  If there aren't any utterly fatal ones pointed out I might just see if I can get others interested in it.  I don't think there is a chance it'll ever happen though.  After all it's  much safer to keep the nukes it would take safely pointed at Russia where they belong. 

    I do have some hands on experience with experimental particle physics from my time at UIC.  I took a very hands on graduate course in it there.  I also took much theoretical physics there.  In particular one project we were involved in was measuring the velocity of cosmic rays that impacted on these detectors we built.  We had to deal with timing, and baselines (of only a few meters at the most) etc.  So I know just how sensitive this can be.  Me and the team I worked with measured some superluminal particle speeds time and again, no matter what we tried.  There are SOOOOO many places to make a mistake in something like this. 


    As for scenarios where particles jump through extra dimensions, or shorten the path between two points by some quirk of relativity (like a quantum worm hole or something) sure.  I just don't think I'll be getting ready to gate to P4x- 67a anytime soon. 
    Science advances as much by mistakes as by plans.
    Halliday
    Hontas:

    As for your comment that "I just don't think I'll be getting ready to gate to P4x- 67a anytime soon", I agree.  I'm not proposing "wormholes" or any other form of "shorten[ed] ... path between two points by some quirk of relativity".  I'm not even advocating "particles jump[ing] through extra dimensions".  I was simply pointing out other aspects of what could (conceivably) be going on (if the CERN/OPERA results are true and valid, of course) that would leave your proposed experiment incapable of being a refutation of the CERN/OPERA results.

    After all, don't we really want something that has the capability to, as you put it, "settle this question once and for all?"  Unfortunately, the issues Derek and I have brought forward strongly suggest that the only way your proposed experiment could do anything like this is in the remote chance that it actually detects superluminal velocities to a similar or higher accuracy as CERN/OPERA.  For if, in the far more likely case, it detects a null result consistent with the supernova experiment(s) it will have answered nothing that such experiments haven't already answered.

    Sorry, again.

    David

    Hontas:

    "No superluminal events have been seen at FNAL or any other accelerator."
    Even if that were true, it would be an argument that CERN/OPERA have got it wrong, not that the phenomenon is independent of energy. 

    How can you possibly say "No superluminal events have been seen at FNAL or any other accelerator."?   "Just a little down the way from your house" MINOS reported FTL neutrinos back in 2007. Of course the result was generally swept under the carpet1 as there was a 1 in 20 chance2 that they got the result by sheer bad luck. 

    A short baseline is another matter entirely, It would need absolute accuracy of about 0.08 ps per meter between the neutrino creation event and its detection in order to see a 25ppm excess velocity. I would love to know what technology they're using to get that.

    Besides all that, your nuke would create a burst of electron antineutrinos. The experiment with electron antineutrinos3 has already been done. It's been known since 1987 that they travel at c, not c plus 25ppm, at least over intergalactic distances. Even the energy range is about the same. 

    The CERN and MINOS neutrinos are muon neutrinos with 6 or 7 orders of magnitude more energy. If you're not bothered about duplicating the type of particle or the energy range then you might as well start firing tomatoes from an air gun to see if they happen to go superluminal.
     
    Odd isn't it, two similar experiments with the same particles and the same energy range, giving the same results? As Harry Hill would say "What are the chances of that happening?"

    1  Meaning Fermilab are doing another experiment.
    2  Meaning 100% certainty.


    p.s Sorry, David, I'd already posted when I saw yours.
    I am not fazed by the 50ns binning at OPERA by the way, it is not a normal distribution but a strictly rectangular one with a negligible further randomness due to timing jitter of the bin edges. This was carefully pointed out in the releases from CERN, it's not something that Sherlock Holmes has uncovered since :) 

    3   Corrected to "anti" some time after posting, in case anyone's bothered.



    Hfarmer
    The Minos experiment you mentioned reported results which were not statistically significant which is the same as no results at all.  That is why no one really paid them any never mind. 
    As for the flavor dependence of this supposed effect I have only one response.  Why?  Why should it depend on flavor?   If neutrinos do oscillate from one "flavor" to the other then really the idea of three separate neutrino's is a bad one.  

    OPERA was originally set up to detect neutrinos changing flavor mid flight.  If they do this then there is no way to know that the muon neutrinos emitted and detected were muon neutrinos throught.

    You see we can play that kind of game in any number of ways. 

    No experiment would be perfect.  That is why we carry out several independent experiments, using different techniques to confirm things like this.   Right?

     
    Science advances as much by mistakes as by plans.
    Halliday
    Hontas:

    You are correct that "No experiment would be perfect."  No two experiments that try to measure the same phenomena will ever be exactly the same.  I don't even think anyone is expecting them to be.  In fact, I believe most would actually want them to be somewhat different, so we have independent measurements of the same phenomena.

    The problem Derek and I are trying to point out is that comparing one experiment that is designed to measure a different phenomenon than the experiment one wishes to confirm or refute will tell you and us little if anything useful—especially when we already have a third experiment that was designed to measure the same phenomenon as your proposed experiment, and one that came up empty, as far as "superluminal" phenomena were concerned.

    So, as Derek pointed out in his post, above, the expectation would be that your proposed experiment would simply see what an already accomplished experiment already did:  Nada.  (So, I'm sure you can see that the chances of your proposed experiment getting "off the ground" become even less likely than you already thought.)

    Sorry.

    David
    Hfarmer
    This experiment was designed to measure the speed of neutrinos VS the speed of photons directly.  They are emitted at one point at one time and if OPERA is right the neutrinos would win by a long shot.  It wouldn't even be close. 
    What experiment "came up empty".  The only relevant observation has been on supernovae. 

    With all due respect David plenty of astrophysicist and astroparticle physicist would disagre with every single assertion you have just made. 

    I swear the way some of you are setting this up unless an experiment is an exact duplication of OPERA then it can always be ignored. 

    Science advances as much by mistakes as by plans.
    "I swear the way some of you are setting this up unless an experiment is an exact duplication of OPERA then it can always be ignored."

    There is a world of difference between demanding an exact duplication of OPERA and pointing out that your experiment is totally different from OPERA and has already been done with negative results.
    Hfarmer
    That's not really the case. Not at all expalined here. 
    http://www.science20.com/comments/89409/Re_It_would_be_%C2%A0Either
    Science advances as much by mistakes as by plans.


    "not statistically significant which is the same as no results at all"

    They were 1.8 sigma. That is not statistically insignificant. It falls short of five or six sigma "proof", but is still only a one in twenty chance of being due to bad luck. Hence my footnote mentioning that Fermilab think it significant enough to be planning a repeat experiment next year. Please don't tell me you are unaware of this.

    "there is no way to know that the muon neutrinos emitted and detected were muon neutrinos throught"
    No-one says they have to be. Even if they oscillate their little flavours off, they are still born in one flavour. And it is more than likely that the FTL phenomenon is associated with their birth not their long flight. 

    "That is why we carry out several independent experiments, using different techniques to confirm things like this.  Right?"

    Wrong. Not "like this". Your "different techniques" don't reproduce the conditions where the putative phenomenon is reported to occur. There are so many natural and, no doubt, artificial, experiments confirming that electron antineutrinos are subluminal that there is not much point in doing another one. Once we know that the muon neutrino result is a real one, then we can start finding its dependency on the different parameters, flavour, energy, baseline and so on.

    You still haven't justified your claim that Fermilab measure short-baseline time differences to better than 80 femtoseconds per meter. Can I take it that they don't or am I hopelessly out of touch with technology?
    Halliday
    Derek:

    When I said "it was revealed that the time clock, on the OPERA side, has only a 50 ns resolution", I was referring to what "was carefully pointed out in the releases from CERN".  I most certainly was not referring to "something that Sherlock Holmes has uncovered since".  Yes, this is indeed what caused the "strictly rectangular" distribution.

    The "problem" is not the distribution, the problem is that an off-by-one error (a very common error in computer programming) would be enough to convert a 60 ± 10 ns early arrival to 10 ± 10 ns (essentially nothing superluminal)—meaning that the 60 ± 10 ns early arrival becomes simply a systematic error.*

    David

    *  Of course, an off-by-one error could also mean we actually have 110
    ± 10 ns early arrival.  Something that would be even harder to ignore (not that we could ignore 60 ± 10 ns, if real).

    Ok, thanks. It was worth making that clear.

    However, nobody in their right mind would build a stopwatch in software when the master clock provides a timestamp for each event. Look what it would need:

    A start signal to zero the counter - prone to off-by-one errors
    An increment on every clock edge - a 50ns interrupt
    A stop signal top freeze the timer and read the result into a store (also prone to off-by-one errors)

    The alternative is simply to take the difference between the two timestamps (which eliminates the risk of start and stop routines creating off-by-one errors).

    As an electronics designer, I have to anticipate "sillies" like this all the time and often specify software requirements - including constraints on the implementation. Programmers do not always like it!However, if a programmer still wants to do things "their way", they have to have the matter reviewed and get the specification changed. I'm not that brilliant an engineer but I'm pretty sure I'd have anticipated this issue and specified the software so that it couldn't arise.

    Clearly something very unusual is happening but I'd be very disappointed in CERN if it were something so obvious to defensive designers like me. We will see.

    Hfarmer
    Clearly something very unusual is happening but I'd be very disappointed in CERN if it were something so obvious to defensive designers like me.
    I can feel where you are coming from.  However when I was studying particle physics at UIC I got a hands on feel for just how complex these experiments are.  There are literally thousands of miles of wires, and tons of electronics that have to hum the same tune for them to work.  
    Even with a much simpler experiment in which we detected cosmic rays using photo multipliers and two solid scintillating materials and one circuit board there were issues.  

    Let me take this opportunity to say that discussing these matters with you has been a pleasure in the spirit of science blogging.  Neither of us insulted the other.  We have made our points with logic and been very strident yet civil.  Unlike some other people.

    As to one of you other replies.  see this 
      
    Science advances as much by mistakes as by plans.
    Well yes, it's nice to keep things friendly. That said, your habit of  sending people on wild goose chases is a great deal more annoying than the odd insult from someone who, on their own admission, ranks quite high on the Asberger scale.  You will win an argument but only because your opponent has died of exhaustion. :)

    It never hurts to say "Oh yes, good point."

    Anyway, I've said my bit and, in the words of the illustrious aforementioned individual, "I'm out of here". 



    Halliday
    Derek:

    I would most certainly share your disappointment if this error turned out to be the case.  However, when one considers that the original intent—the impetus for building the OPERA experiment in the first place—was not to measure potential superluminal velocities in muon neutrino beams, but to measure neutrino oscillations, I find it all too plausible to consider that this particular "defensive design" may not have been foremost in their minds.  Really, this velocity measurement was more like an afterthought:  They basically said "hey, wait a minute, we've got an experiment here, that, if we re-analyze the data this other way, could provide us with velocity data."

    Now, would one hope that even for a neutrino oscillation experiment "defensive design" would have been well incorporated?  Certainly.  However, such "defensive design" probably had a different focus, than the present use of this experiment may now suggest.

    Is the phenomena simply the result of an off-by-one error?  I really don't know.  However, I must consider the possibility.  Mustn't I?

    David
    Oh, of course it needs to be considered, and it's a fair point about adapting the experiment. But I just don't think it likely for the reasons I gave including some human factors militating against it. 

    Not that human beings (if software engineers can be said to be human) are always rational. There is always an irreducible kernel of idiotic decisions that must be allowed for. "But, Mummy, you didn't tell me not to empty the dustbin over little Jonny's head!". We never grow out of it. I just think that an off-by-one error is quite a bit less likely than it sounds at first.  There again, someone a lot cleverer than me said "There are two things that are infinite: the universe and human stupidity. And I'm not sure about the universe."

    Leave it for now. All will be revealed soon.


    You've got to admit, you can't argue with Derek and David's arguments. The experiment tests different particles at different energies, it would prove nothing about what is measured at Gran Sasso.

    Hfarmer
    I just did.  
    What you did was basically make a result that you would want to be true impossible to argue with.  
    Science advances as much by mistakes as by plans.
    Halliday
    Hontas:

    This issue of, essentially, "mak[ing] a result that you [or someone] would want to be true impossible to argue with" is precisely the reason why a good proposed experiment must be capable of refuting the CERN/OPERA results, not just being capable of, possibly, confirming such.

    David
    Hfarmer
    It would be.  Either the light spike from the nuclear reaction would be seen first, or the neutrino spike from the nuclear reaction.    Astrophysicist and astroparticle physicist do this kind of thing every single day.  The only difference would be that everyone could be looking at the same time since they would know when to look.  
    Science advances as much by mistakes as by plans.
    That is precisely the point. Astrophysicists have already established that, over a very long baseline, moderate-energy electron antineutrinos keep to the speed limit.

    A meaningful race has got to be between high energy muon neutrinos and photons.
    Hfarmer
    Then your point is wrong.  Even before the latest result astrophysicist did have many unanswered questions about this. 
    http://arxiv.org/abs/1008.4726

    Most germane to this discussion a number of astrophysicist wonder if they even interpreted that neutrino spike as being for the supernova.  Or was it from some other source who's neutrino emission arrived coincidentally? 

    http://arxiv.org/abs/1109.5172

    OPERA-reassessing data on the energy dependence of the speed of neutrinos

    Giovanni Amelino-CameliaGiulia GubitosiNiccoló LoretFlavio MercatiGiacomo RosatiPaolo Lipari
    (Submitted on 23 Sep 2011 (v1), last revised 27 Sep 2011 (this version, v2))


    The following addresses your concern about the energy dependence. 
    The situation is not equally disastrous for scenarios where the departures from special relativity increase with energy, such as the DSR-compatible case of Eq. (6). These scenarios predict effects for lower-energy SN1987a neutrinos which are of course weaker than the ones they predict for GeV neutrinos. So in principle one could find agreement between a larger effect at GeV energies and a smaller effect for SN1987a neutrinos. But the behavior must be very steep and one of the striking findings of the analysis we reported in the previous section is that, if one empowers the analysis with all the data
    available between 3GeV and 200GeV it emerges that the data situation favors energy independence or at most a softly increasing dependence on energy,
    not a very steep energy dependence such as needed for matching the large difference in magnitude between the feature reported by OPERA and the
    SN1987a bound. 
    Their analysis agrees with my intuition that the effect would likely NOT be energy dependent.  
    And we should stress that looking at the prudent characterization of the bound obtainable from SN1987a neutrinos given, e.g., in Refs. [30, 31] one can very significantly underestimate how steep the dependence on energy would have to be in order to find agreement between the feature reported by OPERA and the SN1987a bound. The bound in Refs. [30, 31]
    very prudently took as reference the overall differences in times of arrival of SN1987a neutrinos and photons, but for a scenario with energy-dependent speed of neutrinos a much more severe constraint is obtained on the basis of the fact that SN1987a neutrinos of different energies reached the same detectors within a few seconds.
    I need say nothing more. 


    Science advances as much by mistakes as by plans.
    Need you not?

    A threshold seems very plausible.

    And according to Paolo Ciafaloni's latest blog, the imaginary rest mass would be ~ 200i MeV, slap bang in magnitude between the supernova and CERN/OPERA.
    Hfarmer
    Yes.  These are the scientific reasons why I think such an experiment could settle some questions.  
    Suppose it shows neutrinos are simply faster than light?  It would mean that earlier observations on Sn1987A were not right, and theories that have neutrinos doing anything more exotic than exceeding c were wrong as well.  

    Too bad we live in a world where some would rather keep those weapons pointed at Russia, for no reason, not even ideological differences. 

     




    Science advances as much by mistakes as by plans.
    Hola Hontas
    I liked your proposal, it is very simple to understand, but
    its performance is almost imposibel, politically speaking.

    You talk a lot of the supernova of 1987, but says nothing of the gamma ray busts (GRBs),
    their origin, at least the long would be the collapse of stars (extragalactic supernovas). A
    GRB is detected here on Earth through its gamma rays and its afterglob X-rays,
    ultraviolet, light, and even radio waves, but no neutrinos, the results of ICE CUBE and other
    experiments are negatives.
    Where are the neutrinos?. Do not forget that GRBs are detected at a rate of at least one per day

    Navia

    Hfarmer
    That's a very good question and I'm glad you asked it. 
    The radiations, light, neutrinos, etc from a supernova or a nuclear bomb would spread out in all directions in a spherical wave.   As the spherical wave spreads out every time you increase the distance by one, the the flux through the sphere will decrease.  The longer the distance the greater the decrease in the flux.   This is the same reason that forces like gravity drop off as the inverse square.   

    From SN1987A we only detected a total of 30 neutrinos spread across the 4 detectors which were then functioning world wide.  That is from a supernova within the galaxy thousands of light years away.  


    The GRB's are occurring millions and millions of light years away.  

    So the neutrino flux through our detectors would naturally be much less from the GRB's than for galactic supernovae.  The neutrino flux would decrease with distance from 30 to... 1 or less.   It's possible that the GRB neutrinos look just like the background noise (Which would include a cosmic neutrino background much like the cosmic microwave background.) 



    Science advances as much by mistakes as by plans.
    The longer the distance the greater the decrease in the flux. This is the same reason that forces like gravity drop off as the inverse square.

    This is also valid to the electromagnetic radiation. However, we can see electromagnetic radiacion from GRBs and no neutrinos

    Navia

    Hfarmer
    _This is also valid to the electromagnetic radiation. However, we can see electromagnetic radiacion from GRBs and no neutrinos

    The reason for that is because neutrinos don't interact with matter as strongly as light does.  

    If the neutrino flux through our detectors from GRB's is 1/100,000 th of what it is for a much closer supernova then the probability of detecting one from a GRB is also smaller.    Instead of detecting a total of 30 neutrino events as from a nearby supernova, we may detect 1 from a distant GRB.  The problem with that is such a signal would get lost in the noise of neutrinos from many other sources. 
    Science advances as much by mistakes as by plans.
    Dear Hontas

    The first signal of superluminal nutrinos were observed by MINUS collaboratio in 2007, using neutrinos from Fermilab;

    Navia

    The SN1987a has already given us a direct footrace enough.

    The fatal error is that the neutrinos are going through rock. And compared with c ( in vacuo )

    You will respond, 'Why should that matter?'

    Exactly. Apparently it does. Why?

    Hfarmer
    The SN1987a has already given us a direct footrace enough.
    There is a bit of doubt in the astronomical community about that.  Some have raised the issue of just how do we know that those particular neutrinos were associated with that supernova and no other possible coincident event?  We could rule that out based on probability alone, but there would still be questions.   In a HUGE universe even a small chance that the signal was a coincidence can be a concern.

    The fatal error is that the neutrinos are going through rock. And compared with c ( in vacuo )

    My initial instinct was along those lines.  That what this experiment showed was some variety of anomalous dispersion.  That is an effect which makes light seem to move faster than c.  Very few others believe this though. 

    You will respond, 'Why should that matter?'

    This is in fact why a "race" between a burst of photons and a burst of neutrinos would be useful and illuminating.   We would know if all neutrinos do this, or just muon neutrinos.  We would know if the effect was flavor and/or energy dependent.   We would know if the dense rock of the Earth caused an effect we did not and cannot anticipate.   Right now all we have are theoretical arguments about these things.









    Science advances as much by mistakes as by plans.
    'a bit of doubt'

    There is a bit of doubt about Einstein's version of relativity, realized in the scalar-tensor interpretation.

    Actually, my concern about the bomb-test is that it would seem so conclusive, that people would simply stop trying to falsify the CERN results and write them off as one of those unexplained and insignificant anomalies and be left untested. 'Probably a distance/time error. Pass the peas...thank-you.' The world economy is in trouble and if science budgets are going to suffer (as they always do) trivial things like neutrinos through matter will get the last consideration.

    The fact is that very few people are talking about the rock factor. Everyone knows neutrinos don't see matter well enough to bother with it as a timing factor. A few people have considered it and a few papers (eg. considering a neutrino 'negative refractive index' that answers to FTL causality and SN1987a concerns) have been written, but little discussed. I see little evidence that people believe it or don't. It's not a topic.

    What I'm seeing is a whole lot of discussion about Glashow's conceptually flawed 'can't be real because Cerenkov loss' which is problematic: if the phenomenon is real then it falsifies our notions of Cerenkov-loss for FTL neutrinos, and not the other way around.

    Hfarmer
    Actually, my concern about the bomb-test is that it would seem so conclusive, that people would simply stop trying to falsify the CERN results and write them off as one of those unexplained and insignificant anomalies and be left untested. 


    Well to the general public it would certainly look like an impressive test.  


    I am not sure how bright a 300 kt thermonuclear bomb would be at a greater distance than the moon from us.  It would be very noticeable. It would involve negotiations to allow an exception to several nuclear testing treaties.  It would involve a international effort by many industrialized nations to properly conduct both the launch, the explosion, and the observations.  This would be a HUGE deal and for the untrained mind it could seem very decisive. 


    Should we let that danger stop us?    It would simply need to be explained that such an experiment would test one big objection to the Neutrino result the only way we can do it with some control.  


    What I'm seeing is a whole lot of discussion about Glashow's conceptually flawed 'can't be real because Cerenkov loss' which is problematic: if the phenomenon is real then it falsifies our notions of Cerenkov-loss for FTL neutrinos, and not the other way around.


    Yes I have seen that problem too.  Theorist can only do two things with something like this result.  Either try to interpret it in the framework of an accepted theory, or propose a new theory. 
    Science advances as much by mistakes as by plans.
    Hontas Farmer said: There is too much fear around the word nuclear. The chance of accidental detonation of an unarmed nuclear device is essentially zero. There is a better chance of being killed by lighting than by the described space mission. Such facts never get in the way of anti-nuclear hysteria.

    Your naivete of launch system failure modes leads you into exposing your own political prejudices here.

    In all extant civilian space launch systems, numerous credible single-failure scenarios (many in fact experimentally confirmed!) are deemed to pose an acceptable level of risk solely due to the presence of an RSS (range safety system). This means a system to designed to deliberately destroy (i.e. blow up) the vehicle in order to prevent it from crashing to earth and causing loss of life or damage to property, either at the launch site or downrange. In such cases, the anticipated dispersion of highly toxic fissionable core materials over a large area is not "hysteria" but a grave concern.

    Of course punching hippies is so much fun, but perhaps next time perhaps you will slow down long enough to educate yourself before indulging.

    Hfarmer
    You don't seem to know how hard it is to arm a nuclear bomb.  

    Unless that explosion goes off in a certain way their cannot be a nuclear detonation.    This is especially true of modern implosion type nuclear weapons.    A series of explosions and explosive lenses is set off in such a way that a collapsing spherical shock wave has to be created to compress the uranium fuel to critical density.  If this is not done precisely then there can be no nuclear detonation.   For this reason alone accidental detonation due to launch system failure is physically unlikely.    That is in addition to all the safety systems. 
    Your naivete of launch system failure modes leads you into exposing your own political prejudices here.
    So you say to someone who remembers the Space Shuttle Challenger disaster all too well. 

    There is a difference between a nuclear bomb going off, and the rocket carrying it exploding.  For example when challenger exploded it killed 7 people who were many miles up.  If a nuclear bomb had been aboard there is zero chance it would have detonated in a nuclear way.  The more likely scenario is radiological contamination in the case of an accident. 

    This is not about politics it's about science. 




    Science advances as much by mistakes as by plans.
    MikeCrow
    A number of Plutonium RTG's have already been launched.
    Never is a long time.