New paper claims that the neutrino is likely a faster-than-light particle | Hacker News Reader

New paper claims that the neutrino is likely a faster-than-light particle

phys.org

59 pointskowdermeister51 comments

If true, this would explain the Fermi Paradox. If there is a faster-than-light particle in this universe, then that is what intelligent life would use to communicate. We can assume that aliens that are smart enough to reach the level that they figure out what a neutrino is, would also, eventually, figure out a way to use it to communicate.

Edit: in case my point wasn't clear, I mean that no intelligent life form will communicate with the standard parts of the electro-magnetic spectrum, which at best travels at the speed of light, if there is a faster alternative. IF there is a particle that travels faster than light, then it seems likely intelligent life will find a way to send that particle in bursts, allowing at least as much communication as is allowed by Morse Code. The point is, the universe is very big, and the speed of light is very slow if you are trying to converse with someone on the other side of your galaxy, or in another galaxy. So if there is a particle that does move faster than the speed of light, it is likely that intelligent life would attempt to use it for communication. This would explain why the SETI project has not picked up anything yet -- they are listening for the wrong thing.

Interesting. I had to look up what the Fermi paradox is: http://en.wikipedia.org/wiki/Fermi_paradox

But this doesn't solve why the Earth wasn't already visited/colonized, correct?

The nearest life-bearing planet is most likely hundreds of light-years away. Faster-than-light communication doesn't mean faster-than-light travel, and nobody wants to sit in a spaceship for 200 years.

True, but the Fermi paradox is about the question of where's everybody, not where's the next galactic pub.

You take a right at Barnards star.

But suspended animation, often used in science fiction films with long spaceflights in them, would make a 200-year-long trip seem an awful lot shorter. I don't think it's too unreasonable to assume that a life-form that achieved near-light-speed travel will have also discovered a way to lie dormant during the trip if necessary.

Also, there's no telling how long an alien life-form might live, or how patient they might be. Basing things on human lifetimes and personalities seems a little anthropocentric given that we know practically nothing about alien life.

As long as we're doing away with assumptions, we should also throw out the one that aliens have a desire to propagate and colonize across the universe.

If you can get near light speed travel, then time dilation means that you won't experience a 200 year trip, only those you left behind. So any species venturing on a one-way trip wouldn't even blink at the prospect of light speed getting in their way.

I'm not a physicist, but as I understand it, it takes light 1 year to travel 1 light-year.

If the nearest life-bearing planet is hundreds of light-years away, even if you could travel at the speed of light, it would still take you hundreds of years to get there, from your frame of reference.

Time dilation just means it would appear to take even longer from the frame of reference of those you left behind (or those you were headed towards).

In the frame of reference of a photon, no time passes between emission and absorption, regardless of the distance it travels.

We haven't even ruled out life on the closest planet to us yet. (Or Mars.)

>We can assume that aliens that are smart enough to reach the level that they figure out what a neutrino is, would also, eventually, figure out a way to use it to communicate.

You can't just assume that understanding a law allows you to violate it. Understanding leads to some advantage, but it may well just be a diversion of resources away from trying the impossible. If it is inherently contradictory that FTL neutrinos can be used for communication, then what you are suggesting is obviously wrong. And seeing as how you don't know that, you'd be foolish to assume it.

It possibly gives an excuse for the lack of transmissions visible, but simple efficiency considerations already explain that. You transmit with the minimum power that works (plus margin), with as much focus as you can get.

Stanislaw Lem used the idea of neutrinos-for-communication as the cause of the "silent universe" in His Master's Voice, which is possibly the best fictional account of how science actually works that I have ever read. Highly recommended.

If there is a faster-than-light particle in this universe, then that is what intelligent life would use to communicate.

SETI-like efforts have a big handicap for a different reason. To oversimplify a bit: any signal that is distinguishable from noise is a waste of energy.

Right now, in the name of spectral efficiency, we're migrating our legacy systems (such as TV broadcast) to modulation formats that sound exactly like white noise to a receiver that doesn't know the coding scheme... and never mind encryption, which has the same effect. Other races will be confronted with the same problems, and will use the same solutions, to the extent they use wireless for medium- to long-range communications at all.

So, the only way we'll detect intelligible signals from an alien world is if we happen to catch them between their development of communications technology and information theory. This is a pretty narrow window -- only about 100 years in our case.

If SETI has any hope at all, it will lie in detecting deliberate beacon transmissions, not incidental RF. But some smart people have argued that attracting attention with such a beacon would be a mistake, possibly the last one the species in question ever makes.

"Other races will be confronted with the same problems, and will use the same solutions, to the extent they use wireless for medium- to long-range communications at all."

This seems a little ahistorical and antropocentric to me.

Ahistorical because even humans have avoided using certain technologies for a variety of reasons -- from certain weapons (chemical/biological, cluster bombs, nuclear weapons, etc) to pesticides, communications technologies, certain programming languages, etc. despite their arguable technological superiority or ability to get the job done.

Anthropocentric because, really, who knows how aliens would think or what they would do? Your argument applies, if it applies at all, to species that think and act much like us. It is debatable whether radically different intelligent (a term which we don't understand even when we apply it to ourselves) species would even understand something as "fundamental" as mathematics the way we do, nevermind actually use technical artifacts in a way recognizable to us.

On the subject of recognizability, could bacteria recognize the humans that they dwell on as intelligent or even living? Can they recognize anything at all? As bacteria are to us, so we may be to alien intelligent life, or even to potentially intelligent life here on earth such as trees, superorganisms like insect or fungal colonies, etc. Organisms that operate at radically different time scales or radically different ways of relating to the world.

Some have argued that the Earth is an organism with agency, or the Internet is one. If that is so, how would we recognize these as such, how would we communicate with them, if it is possible? And if communicating with these on Earth is so unlikely, how much less the likelihood of communicating with beings from other star systems or galaxies utterly unlike that of our own?

If they don't use radio technology we'll of course never hear from them - at least not via SETI. So, when it comes to SETI being effective, the interesting case is where the aliens are using radio technology but never advance their modulation technology to the point where the signal is no longer obviously artificial to an observer without knowledge of the coding scheme. It is of course difficult to say whether this is likely to happen; however, it seems contrived for a species to exist that is okay with using math and physics to construct and operate high-power radio transmitters, but refuses (or is unable to) use math to reach the next level of spectral efficiency.

This seems a little ahistorical and antropocentric to me.

No, the principles involved are absolutely universal. They have to deal with the Shannon limit on Altair 4 just like we do here.

Tachyons cannot be used to communicate FTL even though they have v > c. See http://math.ucr.edu/home/baez/physics/ParticleAndNuclear/tac... for a cool explanation.

Regardless, neutrinos would seem to be a viable communication medium. SETI is considering how they may be used: http://www.seti-setr.org/SETI/neutrinos.html

"When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong." -- Arthur C Clarke

Funny thing is there has already been some success towards using neutrinos to communicate here on earth (http://physicsworld.com/cws/article/news/2012/mar/19/neutrin...). While it's nowhere near efficient currently; I won't dare imagine what could be achieved given a few more years of research.

This article on phys.org appears to be taken verbatim from a press release written by the paper's author, Robert Erlech. (Here's his website: http://mason.gmu.edu/~rehrlich/) From that site, here's a link to what seems to be the original paper: http://arxiv.org/abs/1408.2804

Just as a minor quality signifier, it looks like this paper is categorized under gen-ph ("General Physics") on arXiv.org. That's unusual for mainstream research: topics like this would usually be categorized as "High energy physics" or "Astrophysics". I don't know exactly what criteria arXiv.org uses to judge when a paper should be moved to the "general" category, but I've had the sense that re-categorization is used as a (weak) form of quality control.

I haven't read the paper yet, but this is a truly extraordinary claim. It would take extraordinary evidence (or at least a hint of such evidence) for me to take it seriously.

I originally thought the SN1987A results--which show the neutrino burst from a supernova in the Lesser Magellanic Cloud arriving at the same time as the light, within error-would easily falsify this but forgot that high energy tachyons approach c from above as their energy goes up, so for the 5+ MeV neutrinos that were detected the velocity difference would be negligibly different from c regardless if the mass is positive of negative.

It's a curious result, but I'd still lean toward consistent defects in the data over a tachyonic neutrino, personally.

OK, how does this avoid breaking causality?

If neutrinos are, in fact, tachyons, our notions of causality were already broken.

Besides tachions, it's very interesting to hear somebody talk about the exact mass of a neutrino.

From what I remember of physics, objects get infinitely massive as they approach the speed of light and therefore require infinite energy to get to the speed of light. Is this not correct anymore?

That's an argument for why objects can't be accelerated to and beyond c. But there's a loophole for objects that are already traveling faster than c when they're first created.

> The result relies on tachyons having an imaginary mass, or a negative mass squared.

Perhaps these two were mixed up?

I suspect it's meant to be negative (mass squared) rather than (negative mass) squared.

Correct. Tachyons appear in dynamical equations with imaginary masses, which, when squared, give negative "squared masses".

This is an old hypothesis: http://arxiv.org/abs/hep-ph/9810355

Which is likely why the linked-to article says "three theorists Chodos, Hauser, and Kostelecky suggested in 1985 that they might be hiding in plain sight – specifically that neutrinos are tachyons".

I am always weary of a sole authored physics paper, especially in particle physics. Either he had nobody working with him, or nobody wanted their name associated with the work, both raise red flags these days.

Direct link to arxiv paper: http://arxiv.org/abs/1408.2804

Instead of attacking the person who wrote a hypothesis about neutrino speed, do you know who will be duplicating his experiment?

I didn't see the comment as a personal attack. It was merely pointed out that the commenter finds papers with a sole author to be questionable.

As for "his experiment", if you actually read the article, you can see that there apparently was no experiment; rather, the paper's conjecture relies on analysis of data from other observations and experiments. So the answer is that nobody will be duplicating the experiment in question, since it does not exist.

"It was merely pointed out that the commenter finds papers with a sole author to be questionable."

That's an argument from authority and/or consensus.

At the end of the day, only reproducibility matters in science. The problem with using unreliable heuristics like "single author papers" is that it means the findings of such papers are less likely to be tested or further investigated by others. It introduces a strong herd effect bias into science, which history has shown is not a good idea.

What a scientists' peers think of a paper is important evidence for the general population. Unless you are actively studying a particular field, proxying your expectations to people who are involved with that field is a good idea. It's a heuristic, but it's a useful one.

History has shown that heuristics like this are a fantastically good idea. They've been part of science more or less since science started, and science has accomplished an enormous amount. The number of bold, exciting claims that are entirely wrong is far larger than the number of bold, exciting claims that are even partly correct. Heuristics like "put less trust in single-author papers" (among others) are essential for science to actually make progress rather than spending all its effort chasing mirages. Yes, sometimes an important idea gets overlooked for a decade or two along the way, but the alternative would be to accomplish nothing at all.

(Unless you've been a physicist at a major university, you have no idea how many emails those folks get claiming to have quantized gravity or to have proved Einstein wrong.)

As a colleague once put it, "I believe papers published by people I know. Failing that, by people who have worked with people I know. In third place, by people who are at institutions I know have a history of good work."

Science has a deep internal tension that drives it forward, because it is both inherently elitist and necessarily public. If results are not published they aren't science, because they aren't incorporated by the scientific community. And yet while a) anyone can do science and b) anyone can publish, it is still the case that c) the scientific community is overwhelmingly tightly knit and fairly conservative when it comes to adopting new ideas, and the number of new ideas that get generated is so high that this sort of heuristic really is extremely valuable.

Sure there are lone geniuses. There are also lone nutjobs. It's not difficult to guess which one predominates, and these sort of filters do a good enough job of bringing the nut/genius ratio down closer to unity that we are always going to use them.

Statistically, if you always dismiss novel claims you will be right almost all the time.

Yet this requires no intelligence at all. It's akin to a wall following msze solver. Wall following maze solvers do work, but only for the subset of mazes that are simply and directly connected end to end.

You are correct that some way of sorting signal from noise is required, but I think it's got to be something up to the task. There is also clearly a breadth/depth tradeoff at work here that demands some amout of cost/benefit analysis. At one extreme you have rote dogma O(1), and at another you have full iterative search of the combinatorial space of all theory O(n^n^...).

The way I think about issues like this is greatly informed by my study of learning theory, which if studied deeply infuses one with a great phobia of the dreaded local maximum and a suspicion of any and all deterministic non-adaptive learning strategies... As these tend to converge at local maxima. See: no free lunch theorem, among other things. My maze solver analogy is a pretty good simple one for how the space of learning algorithms maps to the space of fitness landscapes.

The ideal strategy would probably be to run multiple heuristics concurrently or switch them up over time. For example, science might embark upon multi decade investigations of orthodoxy punctuated by jubilees where an accumulated queue of minority and fringe theories are investigated. Successes here form the next set of orthodoxies, rinse and repeat.

For particle physics phenomenology, that's essentially what the field is, people developing physical models and predicting what would be observed due to such models in other experiments...since it's not exactly easy to perform particle physics experiments.

He used other derived data, and didn't himself perform any experiment which can be duplicated. We'll hopefully get a better understanding of neutrino mass from KATRIN [1], which will likely lead to additional insights into their speed.

1. http://en.wikipedia.org/wiki/KATRIN

Science != PR

Neutrino is faster than light in the water. To decide about vacuum we have to wait for another nearby supernova.

Neutrino being faster than light when both in the water doesn't mean anything regarding c as a barrier.

it's a well accepted fact that neutrino bursts precede EM effects in supernovae.

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