Uncharted Territory

November 10, 2011

Still Debunking Fast Neutrinos

Filed under: Neutrinos, Physics, Relativity — Tim Joslin @ 1:59 pm

I mentioned in my previous post that “I submitted a paper with a more thorough explanation [of the apparent super-luminal neutrinos detected in the CERN-OPERA experiment] to ArXiv a week ago”. As I write, ArXiv are refusing to publish the paper, without giving reasons in sufficient detail for me to take any corrective action. With hindsight I should perhaps have made the title even less provocative, shortened the Abstract, put the Acknowledgements at the end, rather than on the front page and so on – in each case, “it seemed like a good idea at the time”, and I’m wondering now whether I’ve done something that screams “amateur”. As if that should disqualify me from publishing. But all these things are cosmetic and I was concentrating on the science itself. At the time I didn’t realise there was a significant moderation hurdle on ArXiv – I thought the key was to get an endorser. I was also keen to get my idea “out there”. I figured that if something needed changing they’d just ask me to do it. Anyway, more about my travails in trying to catch the attention of the “physics community” another time.

Here, I want to provide an up to date version of my “Explanation of Apparent Superluminal Velocity in the CERN-OPERA Experiment” (pdf) together with a few words of explanation. This version is significantly different from the one I included in a previous Uncharted Territory post. Postscript: This version has now been submitted to viXra.org, an alternative to arXiv that I came across yesterday.

To recap, my argument is that the neutrinos are travelling at the speed of light, but the speed of light varies slightly depending on direction, because of the motion of the Earth, which is travelling at an estimated 300km/s as measured against the cosmic microwave background (CMB) radiation, which, being the same in all directions, can be taken as providing a stationary reference. It is very difficult to measure the one-way speed of light directly, and the experiments that have been carried out have determined instead c, the “round-trip” light speed. The CERN-OPERA neutrino velocity measurement experiment has unintentionally measured the one-way light speed by comparing neutrino flight times with the expected flight time at c, determined by measuring the distance between CERN and OPERA and successfully transmitting the time at CERN to the OPERA neutrino detector.

The reason for the new version is that I was a bit slow on the uptake. It was only on 27th October, just as I was about to submit to ArXiv, that I belatedly realised that the GPS doesn’t somehow use the “one-way” light speed, but provides a timing based on the “round-trip” light speed. At first I’d thought the whole problem was caused by the procedure for calculating the delay in the optical fibre used to transmit the timing signal over the last 10km into the Gran Sasso mountain to the OPERA neutrino detector. Then, around 25th October, I’d realised that sending a timing signal down an optical fibre runs into the same problems as moving a clock to measure a signal transmission time. On 27th I realised that the GPS also does something similar. A timing signal is sent from the GPS satellite to CERN and to Gran Sasso.

Schematic of CERN-OPERA neutrino velocity measurement experiment

In each case (using the labelling A – CERN, B – Gran Sasso and C – the OPERA neutrino detector) – (i) transmitting a timing signal via GPS from A to B, (ii) moving a clock from B to C to measure a delay in signal transmission, and (iii) transmitting a timing signal via optical fibre cable from B to C – you simply can’t use the time which the transmission has noted it was sent at to measure the speed of light. It’s slippery, but if you really concentrate on the problem, you’ll realise, as did Henri Poincaré, the hero of my previous post, that in each case you have to assume the light speed transmission time.

The best analogy I can come up with is if I received a letter from my nephew – undated, sent 2nd class, with an illegible postmark, as is usual these days – saying I’d forgotten his birthday. I’d be unable to pin down exactly when his birthday was. I’d have to guess how long the letter had taken to reach me.

Similarly, in case (i) in the CERN-OPERA experiment, a “common-view” timing signal is transmitted from a GPS satellite to clocks at CERN (point A) and Gran Sasso (point B), for the express purpose of synchronising those clocks. This signal simply includes the message “the time here is t_SAT”, where t_SAT is whatever the time is on the satellite’s clock. Now, the crucial point (which I only appreciated on 27th October) is that if the message takes n seconds to reach one of the clocks then it’s also n seconds out of date. Unless you know n you can’t tell what the time actually is at the satellite when you receive the message. This is established in the experiment by subtracting the distance from the satellite to the clock and dividing by c, the “round-trip” speed of light, adding the result to the time at which the message was sent. In fact, our whole system of Coordinated Universal Time (UTC) depends on subtracting the assumed transmission time of signals, determined by dividing distance by c, the round-trip light speed. Procedure (i) thus synchronises time between A and B, assuming light travels at c in both directions.

In case (ii) a clock is transported from a master clock at Gran Sasso (point B in the paper, synchronised with CERN by GPS) into the mountain to the OPERA neutrino detector (at point C in the paper) in order to establish the transmission delays in an 8.3km optical fibre (actually this is only the longest fibre in the experiment, but the argument is the same for the others). The transmission time, t_tr in the paper, is the time light would have taken to travel the distance of the cable into the mountain, plus the delays caused by the cable and associated equipment, which I’ve called t_sig. It’s t_sig we want to find out. But again, the signal includes no information about the duration of transmission at light speed. Again, if it takes n seconds to arrive, it’s n seconds out of date when it reaches the clock at the neutrino detector.

Case (ii), though, is slightly different from (i) and highlights the subtleties inherent in the problem. Here, we have a clock at C which we believe shows the time at B, assuming events at B and C are simultaneous. We can therefore establish the delay, t_sig, in transmitting the signal from B to C. But, if events at B and C are not simultaneous, as Einstein suggested, because of the Earth’s motion, then the delay in (or early) arrival of the signal at C compared to light speed transmission from B is exactly matched by the delay in (or early) time at C compared to that at B. Once the clock is moved from B to C it is no longer synchronous with the clock left at B. This is analogous to the Sagnac Effect, whereby clocks have to be adjusted to allow for the rotation of the Earth, and clocks that are moved lose synchronicity. It is in itself an important result, and I intend to devote a post solely to this point (though I don’t always keep my promises). Returning to the CERN-OPERA neutrino velocity measurement experiment, the outcome is that we’re no better off physically moving a clock from B to C than we are transmitting the time from B to C. We always obtain the same delay, t_sig. It might be worth noting that, in the experiment, the same t_sig was obtained by a different procedure (the two-way fibre delay calibration procedure) that doesn’t depend on physically moving clocks.

In case (iii) we do actually transmit a timing signal from B to C along the fibre-optic cables, using the calculation of the delay obtained in procedure (ii). We don’t know how long the timing signal takes, because, again, if it takes n seconds to transmit, it is n seconds out of date, but we assume the delay compared to light speed transmission is t_sig. Thus, the expected time of flight over the entire neutrino flight path has been calibrated based on c, the round-trip light speed – the time of arrival of the timing signal at C against which neutrino flight times are compared is t_A + x_3/c + t_sig (where t_A is the time at A, CERN, when the neutrinos were created and x_3 is, as in the paper, the distance from A to C).

It has to be said that the CERN-OPERA team have done a good job. I’m convinced they are excellent experimenters. The problem is theoretical. It appears they succeeded in establishing a timing signal at point C, the OPERA neutrino detector, that very accurately represented the arrival time of neutrinos emitted from point A, CERN, based on a round-trip light-speed, c, neutrino velocity. The trouble is the neutrinos were only travelling one-way.

The method I’ve adopted in the paper to demonstrate the point is to show that the measurements to determine the expected neutrino flight time at light speed, that is those used in the calculation of the timing signal delay at C relative to A, would all be the same for an observer moving relative to the experiment, but the actual neutrino flight time would depend on the motion of that observer. This is the point of the Lorentz transformations in the paper.

The experimenters have assumed they are stationary relative to the neutrinos, but since the neutrinos arrived earlier than expected, this is clearly not the case. The paper therefore goes on to calculate the velocity of the experimenters relative to the neutrinos, or to be more precise the “frame of reference” of the neutrinos. Because of the details of the experiment this can only be done in the average case. We can only determine one component of our motion relative to the neutrinos, that is that along the Earth’s axis. The rest of our motion varies with the Earth’s rotation and orbit and I assume these motions cancel out to zero.

This is where it gets really interesting. I can’t get the result to tally exactly with the Earth’s motion against the CMB. That leaves me wondering whether the problem is due to experimental error or real – in which case satellites such as WMAP have not measured our motion correctly against the CMB. If the problem is real, and we have measured something other than our motion against the CMB, then things could get very interesting indeed.

Advertisements

4 Comments »

  1. Before 23 years, I had proved mathematically that relative velocity may be more than light velocity. CERN proved experimentally that velocity of Neutrinos may be more than light, if this news will be confirmed then that will be new beginning of physics.
    Please read paper “What is matter & dark matter is made up of?” on my web site http://www.maheshkhati.com. This paper may help to find solution to problems like what is dark matter? & about true relativity. I strongly oppose special theory of relativity

    Comment by Mahesh Khati — November 10, 2011 @ 8:47 pm

  2. Hi Tim,

    I feel with you, because I am in somewhat the same position. I’m not a scientist, but a retired technician from 1941 with extensive experiense in analogue and digital HW engineering ass well as SW engineering, holding 8 patents, the last one granted in 1998.
    I prepared two articles, one showing where OPERA’s analysis went wrong and the other a proposal to do it right.
    It is my intention to publish these in arxiv, but I have difficulties finding a reviewer/editor/statistician who can help making the articles fit for publication.
    I agree with you that the exact redaction of a paper or the status of the author should not overrule the arguments presented.
    On the other hand, jargon plays a role and ego’s exist. An endorser with a scientific background would certainly help, but you must be able to convince her or him first.
    I must confess that I miss the background to follow your arguments.
    Maybe you can follow mine.

    In an experiment there is always a stimulus and a response.
    Using a response for which there is no corresponding stimulus is invalid, because there was no experiment.
    Using a stimulus for which there is no corresponding response is invalid as well, for the same reason.
    The latter is the case in the current analysis of the OPERA Collaboration.

    Only a part of the PEW contains start time information of the proton (stimulus) that later resulted in a neutrino detection (response).
    The remaining parts or the PEW contain start time information of protons for which there was not a neutrino detection.
    The current analysis allows the remaining parts to determine the shape of the PDF; it cannot be ruled out that this results in bias, because of the irrelevant start time information in the PEWs.

    A number of physicists pointed out that these remaining parts are required for constructing the PDF to enable the maximum likelihood analysis and they dismissed the idea that this was invalid.
    This seems the mainstream view and I am wondering what to think about that.
    It explains why the analysis is taken for granted.
    See also http://sites.google.com/site/bertmorrien/

    I wish you luck with your paper.

    Bert

    Comment by Bert Morrien — November 13, 2011 @ 10:12 pm

  3. […] #split {}#single {}#splitalign {margin-left: auto; margin-right: auto;}#singlealign {margin-left: auto; margin-right: auto;}#splittitlebox {text-align: center;}#singletitlebox {text-align: center;}.linkboxtext {line-height: 1.4em;}.linkboxcontainer {padding: 7px 7px 7px 7px;background-color:#eeeeee;border-color:#000000;border-width:0px; border-style:solid;}.linkboxdisplay {padding: 7px 7px 7px 7px;}.linkboxdisplay td {text-align: center;}.linkboxdisplay a:link {text-decoration: none;}.linkboxdisplay a:hover {text-decoration: underline;} function opensingledropdown() { document.getElementById('singletablelinks').style.display = ''; document.getElementById('singlemouse').style.display = 'none'; } function closesingledropdown() { document.getElementById('singletablelinks').style.display = 'none'; document.getElementById('singlemouse').style.display = ''; } Breaking the speed limit of the universe?I’m Shocked! Shocked To Find That There Are Neutrinos Going On HereStill Debunking Fast Neutrinos […]

    Pingback by Why is the universe black? What is dark matter? How can a black hole vacuum light? | Ultra Light Vacuum — November 24, 2011 @ 8:02 pm

  4. Hi Tim

    I found your work very interesting!
    I even had some ideas similar to yours …
    (see http://www.atomlig.com.br/poli/WitteEffect-IG.pdf)
    Only to the Earth speed I not using the CMB, but the results of Miller and Witte experiments: (http://www.orgonelab.org/EtherDrift/CahillDeWitte2006.pdf).

    “The most thorough interferometer experiment was by Miller in 1925/26. He accumulated sufficient data that in conjunction with the new calibration understanding, the velocity of motion of the solar system could be determined† as (α=5.2hr, δ =−67◦), with a speed of 420±30 km/s. This local (in the galactic sense) absolute motion is different from the Cosmic Microwave Background (CMB) anisotropy determined motion, in the direction (α=11.20hr, δ =−7.22◦)”
    However there are two problems with this approach:
    – The Earth’s rotation causes variations in delay time, with the delay and the outer operate this type of variation was not observed.
    – The MINOS experiment has the opposite direction from the operator and in this case the movement of the earth should produce an opposite result (neutrinos slower) but neutrinos in MINOS are also getting a little ahead of time.

    If you want to discuss this issue better get in touch!’
    (poli*******@gmail.com)

    Best Regards
    Policarpo

    Comment by Policarpo Ulianov — January 3, 2012 @ 8:45 pm


RSS feed for comments on this post. TrackBack URI

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Blog at WordPress.com.

%d bloggers like this: