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Another Look at FTL Neutrinos and Wormholes

by John G. Cramer

Alternate View Column AV-163
Keywords: CERN, superluminal, neutrinos, experimental, problems, retraction, wormholes, time, dilation.
Published in the July-August-2012 issue of Analog Science Fiction & Fact Magazine;
This column was written and submitted 2/4/2012 and is copyrighted ©2012 by John G. Cramer.
All rights reserved. No part may be reproduced in any form without
the explicit permission of the author.

 

In two recent AV columns I described the report of superluminal mu-neutrinos by the OPERA Collaboration at CERN , and I described a scheme for reaching the stars in a hurry by accelerating micro-wormhole mouths to velocities near c and exploiting relativistic time dilation  to reach nearby stars in a few days or weeks.  In the case of the FTL neutrino discussion, there was a problem in the wording of the observed effect in my column, and there are now new developments in the observation itself.  In the case of the travelling wormholes, there have been some reader responses indicating that I need to explain the application of relativity better.  This column is an update on these previous columns.


First, my column in the February-2012 issue of Analog stated: “The result was that the time of flight of the m-neutrinos could be determined to a statistical precision of about 6.9 nanoseconds (ns) and a systematic uncertainty of 7.4 ns, and has a value of 60.7 ns.  The phrase in italics was a misstatement.  The value of 60.7 ns was the “early arrival” time measured for the mu neutrinos, as compared to the arrival time that would be expected for particles traveling exactly at the speed of light (299,792,458 meters per second).  The measured distance from the CERN neutrino source to the Grand Sasso detector was 730,534.61 meters, so the time of flight of speed-of-light neutrinos would be 2,436,801.2 ns and the time of flight measured by OPERA would be 2,436,740.5 ns.  It was not clear in my column that the quoted number was the residual resulting from a subtraction, not the actual time of flight.

But now there have been new developments from CERN .  Interestingly, the OPERA report of superluminal neutrinos last September made a much bigger media splash than the February 7, 2012 report from CERN that the ATLAS and CMS collaborations have released preliminary evidence indicating the possible presence of the Higgs boson at 124-126 GeV.  But recently there has been a February 27, 2012 press release from CERN on the superluminal neutrinos that reads as follows (italics mine):

“The OPERA collaboration has informed its funding agencies and host laboratories that it has identified two possible effects that could have an influence on its neutrino timing measurement. These both require further tests with a short pulsed beam. If confirmed, one would increase the size of the measured effect, the other would diminish it. The first possible effect concerns an oscillator used to provide the time stamps for GPS synchronizations. It could have led to an overestimate of the neutrino's time of flight. The second concerns the optical fiber connector that brings the external GPS signal to the OPERA master clock, which may not have been functioning correctly when the measurements were taken. If this is the case, it could have led to an underestimate of the time of flight of the neutrinos. The potential extent of these two effects is being studied by the OPERA collaboration. New measurements with short pulsed beams are scheduled for May.”

Let me interpret.  After months of checking every conceivable source of error, OPERA has uncovered two problems.  Problem 1: an oscillator that was used on conjunction with the GPS system to time-stamp the arrival of neutrino detection events was erratic in the direction of reading high, and Problem 2: a diode in an optical fiber link synchronizing GPS time signals with the master OPERA clock was faulty. (Note: this was not a loose connection, as some press reports have suggested).  Problem 1 would erroneously trim the measured early arrival time of 60.7 ns to smaller values, while Problem 2 would erroneously push the measured early arrival time of 60.7 ns to larger values.  In particular, Problem 2 could very well be responsible for the reported “superluminal” early-arrival effect.

What can be done to correct these problems?  The experimenters must replace the offending electronic modules and rerun the experiment.  Therein lies the difficulty.  It is easy enough to fix the electronics, but the data already recorded by OPERA has been spoiled, because the random changes introduced by the faulty components cannot be retroactively corrected.  New data is needed to replace the three years of data on which the previous results were based.

Fortunately, that re-do should take considerably less than three years.  The old data relied principally on the “shoulders” of microseconds-long beam-spills to determine neutrino arrival times.  New SPS beam-bunching techniques can deliver short time-pulses of neutrinos instead of prolonged spills, and this will significantly improve the data analysis situation and bring new results much sooner.

Nevertheless, this will take time, and the present situation is that there is now no compelling evidence for superluminal neutrinos.  Einstein’s special theory of relativity has prevailed once again. 


On the matter of accelerated wormhole mouths, reader Harlan R. Cohen reported that he thought he might be reading an “April Fools” issue of Analog after reading my column entitled “Shooting Wormholes to the Stars”.  He seems to think that the effect I was describing has something to do with the refraction of the Doppler-shifted light passing through a wormhole.  Clearly, the idea on which that column was based must need more clarification.

What Morris, Thorne, and Yurtserver (MTY) discovered about wormholes, based on general relativity, is that when one end of a wormhole goes on a trip at a speed near c, relativistic time dilation changes the space-time connection between the two ends of the wormhole from a connection across space to a connection across time.  The traveling end of the wormhole connects back to an earlier time for the stay-at-home end, and the wormhole is now a two-way “time tunnel” connecting the past to the future.  That is a difficult concept to grasp, but it is what emerges from consideration of Einstein’s equations of general relativity.

Perhaps the best way of understanding the concept is to consider that each end of the wormhole contains its own ticking clock.  Independent of everything else, the clock ticks of the two ends are locked together.  Each end matches the other, tick for tick.  But if one wormhole end is moving at nearly the velocity of light, special relativity tells us that its clock slows down and ticks slower, while the clock of the stay-at-home wormhole end continues to tick at the normal rate.  How can this be, if they are locked together?  MTY found that to maintain this synchronization, the wormhole must be made to span a time interval, with the fast end moving to the future of the slow end.

For example, suppose a travelling wormhole end (T) moves fast enough (at 99.5% of c) to have a Lorentz factor g of 10, while the other wormhole end (H) remains in the laboratory at rest with a Lorentz factor of 1.0.  The Lorentz factor g is the amount by which time slows down, space in the direction of motion contracts, and mass increases for a moving object.  Suppose T travels away from the Earth for half a year, then reverses course, travels back to the laboratory at the same speed, and stops.  As far as an observer on T is concerned, the round-trip travel time would be just 36.5 days, while for an observer at H it would have taken 365 days.  Therefore, in the laboratory if you move through the wormhole from H to T, it will take you 36.5 days into the future, while moving through the wormhole from T to H would take you 36.5 days into the past.

Now, suppose you remain in the laboratory during the trip, looking through H and watching the travels of T.  Due to the locking of the clocks, you will see the same thing an observer riding on T would see.  The stars will be radically blue-shifted ahead, red-shifted behind, and levered forward by Doppler shift effects, the turn-around point will be reached in just 18.25 days, and the return trip will take just another 18.25 days.  Through the wormhole looking from H to T, you would see T enter the laboratory and stop.  But in the laboratory, you will have to wait another 328.5 days for T to actually return.  That is the peculiarity of a time-spanning wormhole.  All of this is discussed or implicit in the MTY paper.

The twist that I introduced in my previous column was to give the T wormhole end a really large Lorentz factor of g = 7,455, the g-value that will be reached for colliding protons when the CERN LHC begins operation at it design acceleration, and send it off on a one-way trip to explore the stars.  With the LHC acceleration, the wormhole end T would be travelling at 99.99999910% of the speed of light, so from the point of view of a stay-at-home observer it travels one light year per year.

However, from the viewpoint of a hypothetical observer riding on T, his clock is ticking much slower (as are his mental time sense and biological processes), and for him moving one light year takes only 70.5 minutes.  And because the clocks at the wormhole ends are locked together in their ticking, an observer back in the lab on Earth, looking from H to T, sees the highly distorted local scenery (with visible photons Doppler-shifted to x-rays) of a light year away.  For our observer in the laboratory on Earth, it actually (in some relativistic sense of the word “actually”) took the wormhole end T a full year to make the trip, but because of relativistic time dilation as it applies to wormholes, when he looks through H he is seeing, through his wormhole time-machine, the distant location almost one year in his future, at the time when T has moved a light year away.

One might raise the objection that Einstein taught us that no observer in any reference frame ever sees anything moving faster than c.  How, then, can our observer riding on T see himself covering a light year in 70.5 minutes?  The answer is that because of his great speed and Lorentz factor, he sees the distance ahead of him contracted by a factor of g, so that from his point of view he has traveled a distance of only 70.5 light-minutes instead of one light year.

In my previous column I emphasized the effect of wormhole “back-reaction” and local conservation laws in this kind of wormhole physics.  I note that these points have not been appreciated or used by many SF writers who employ wormholes in their works of fiction.  I also discussed how such travelling wormhole ends might be accelerated on Earth, steered with mid-course corrections toward their desired destination using back reaction, decelerated when they arrived, and even expanded to transport explorers, colonists, etc.  None of this is anything we can do at our present level of technology.  As MTY emphasized in their seminal paper, this is something that an “advanced civilization”, (i.e., not us) might be able to do with wormholes. 

I’m not sure any of this actually brings the stars any nearer, but I find it comforting to think that the physics “end run” of accelerated wormholes could, at least in principle, make distant star systems only a few days or months away.


References:

CERN Press Releases:

“OPERA experiment reports anomaly in flight time of neutrinos from CERN to Gran Sasso”, 23 February 2012, URL: http://press.web.cern.ch/press/PressReleases/Releases2011/PR19.11E.html .

“ATLAS and CMS experiments submit Higgs search papers”, 7 February 2012, http://press.web.cern.ch/press/PressReleases/Releases2011/PR25.11E.html .

Wormholes:

Michael S. Morris, Kip S. Thorne , and Ulvi Yurtsever, Physical Review Letters 61, 1446 (1988).

Matt Visser, Lorentzian Wormholes, American Institute of Physics Press, Woodbury , NY , (1996); ISBN: 1-56396-653-0.  


SF Novels by John Cramer:  my two hard SF novels, Twistor and Einstein's Bridge, are newly released as eBooks and are available at : http://bookviewcafe.com/bookstore/?s=Cramer .

AV Columns Online: Electronic reprints of about 170 "The Alternate View" columns by John G. Cramer, previously published in Analog , are available online at: http://www.npl.washington.edu/av.


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