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Low-Energy Neutrinos Detected In Real Time

Roland Piquepaille sends us word of first results from the Borexino detector in Italy, where an international team of more than 100 researchers has detected low-energy solar neutrinos for the first time. These results confirm recent "theories about the nature of neutrinos and the inner workings of the sun and other stars." In particular, it's now almost certain that neutrinos oscillate among three types, namely electron, muon, and tau neutrinos. The Borexino detector lies almost a mile underground near L'Aquila, Italy, and it sets new standards in the purity of the materials used in its construction.

73 comments

  1. Neutrinos by the_kanzure · · Score: 4, Informative

    * Neutrino
    * History of the neutrinos [from our perspective, mind you]
    * The Ultimate Neutrino Page
    etc. I should go call up my particle physicist body to post up some comments. :)

    1. Re:Neutrinos by FoxDude0486 · · Score: 1

      Thank god for your first post! I was wondering if this article was a joke or not.

    2. Re:Neutrinos by Anonymous Coward · · Score: 1, Funny

      I should go call up my particle physicist body to post up some comments.

      We'd really rather not know about your body collection. Especially if you use them to post comments. Try alt.killers.serial
    3. Re:Neutrinos by Anonymous Coward · · Score: 0

      or alt.killers.CEREAL

  2. The paper by Angstroman · · Score: 5, Informative

    For those interested, the paper itself can be found at http://arxiv.org/abs/0708.2251v1. The team is detecting neutrinos from Be 7 at the rate of 47 per day.

    1. Re:The paper by FuzzyDaddy · · Score: 2, Interesting
      I used to work on the KAMIOKA neutrino detector project (as a lowly undergrad). We looked at Chernkov radiation from scattered electrons, and saw about 1 a day, with huge background (the detector triggered about once a second or more, IIRC.) And certainly not realtime, there was a huge amount of post processing required.

      The Chernkov detectors do give you direction information which this detector does no - but the sensitivity is really impressive.

      One interesting aspect of this result is that it probes the presents of 7Be, which can give us a lot of insight into how the various nuclear reactions are taking place, and at what rates. It wouldn't be possible without a confirmation of neutrino oscillation, which cuts our measured neutrino flux by a third (I believe.)

      --
      It's not wasting time, I'm educating myself.
  3. Karma Whore by imsabbel · · Score: 0, Offtopic
    --
    HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
  4. Re:Neutrino jokes here: by dsginter · · Score: 3, Funny

    Neutrinos - the cornerstone of *any* nutritious breakfast! (Man, this cereal goes *right* through me!)

    Homer: Mmmmm... elementary particles!

    --
    More
  5. Some basic papers by the_kanzure · · Score: 4, Informative
    TASI 2002 lectures on neutrinos [Yuval Grossman] [PDF]:

    We present a pedagogical review of neutrino physics. In the first lecture we describe the theoretical motivation for neutrino masses, and explain how neutrino flavor oscillation experiments can probe neutrino masses. In the second lecture we review the experimental data, and show that it is best explained if neutrinos are massive. In the third lecture we explain what are the theoretical implications of the data, in particular, what are the challenges they impose on models of physics beyond the SM. We give examples of theoretical models that cop e with some of these challenges.
    Neutrino physics [Evgeny Khakimovich Akhmedov] [PDF]:

    In the present lectures the following topics are considered: general properties of neutrinos, neutrino mass phenomenology (Dirac and Majorana masses), neutrino masses in the simplest extensions of the standard model (including the seesaw mechanism), neutrino oscillations in vacuum, neutrino oscillations in matter (the MSW effect) in 2- and 3-flavour schemes, implications of CP, T and CPT symmetries for neutrino oscillations, double beta decay, solar neutrino oscillations and the solar neutrino problem, and atmospheric neutrinos. We also give a short overview of the results of the accelerator and reactor neutrino experiments and of future projects. Finally, we discuss how the available experimental data on neutrino masses and lepton mixing can be summarized in the phenomenologically allowed forms of the neutrino mass matrix.
    BTW, particle physics has an awesome WWW presence.
    1. Re:Some basic papers by sholden · · Score: 5, Funny

      BTW, particle physics has an awesome WWW presence.

      It's almost as if the world's largest particle physics laboratory had something to do with creating it.

      Spooky!
    2. Re:Some basic papers by sayfawa · · Score: 2, Funny

      Al Gore is a particle physicist?

      --
      Free the Quark 3 from asymptotic confinement! Bring your charm! Don't get down! All colours and flavours welcome!
    3. Re:Some basic papers by MyLongNickName · · Score: 3, Funny

      Al Gore INVENTED particles.

      --
      See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
    4. Re:Some basic papers by morgan_greywolf · · Score: 1

      It's almost as if the world's largest particle physics laboratory had something to do with creating it. Yeah, they needed somewhere to send those particles, so they made all those tubes!

    5. Re:Some basic papers by GundamFan · · Score: 1

      OK, not on topic but it did make me chuckle.

      --
      I don't give a damn for a man that can only spell a word one way.
      Mark Twain
    6. Re:Some basic papers by HungSoLow · · Score: 1

      Action at a distance!

    7. Re:Some basic papers by Anonymous Coward · · Score: 0

      So if we'd elected him way back when we, conceivably, might have had a president who not only could launch nuclear weapons but might also have been able to pronounce them correctly?

    8. Re:Some basic papers by Bemopolis · · Score: 1

      And Dubya says that the jury is still out on the existence of particles. But don't worry; Halliburton just got a rocket contract, so Cheney is drawing up plans to invade the Sun.

      Mock away, liberal pussies, but neutrinos are Weakly-Interacting particles of low-Mass Destruction.

      --
      "I guess the moral of the story is, don't paint your airship with rocket fuel." -- Addison Bain
    9. Re:Some basic papers by Anonymous Coward · · Score: 0

      Particle man... Particle man...

    10. Re:Some basic papers by wolf369T · · Score: 0

      In Soviet Rusia, particles invents Al Gore!

  6. Gran Sasso by xPsi · · Score: 5, Informative

    Borexino is really an amazing detector, but has a complex history. The experiment is located at an impressive place called the Gran Sasso National Laboratory (LNGS) in Italy. Technically, it is one of the deepest labs in the world as measured by overburdon -- i.e. it has about a kilometer of rock in every direction to shield cosmic rays-- but is actually located high up in the mountains. Interestingly, it is almost directly under where Mussolini was held prisoner and subsequently rescued by German commandos at Campo Imperatore in 1943. It is also near where the movie Ladyhawke was filmed. Anyway, back in 2002 there was a chemical accident when some of the liquid scintillator material (highly toxic) got into the local ground water. The leak was an honest mistake and was actually rather minor as chemical spills go, but it caused a public relations debacle which tangled up the lab and, in particular, Borexino, in a long bureaucratic nightmare. I'm happy to see they are now back in the game producing cutting-edge results.

    --
    i\hbar\dot{\psi}=\hat{H}\psi
    1. Re:Gran Sasso by Sunburnt · · Score: 1, Funny

      Anyway, back in 2002 there was a chemical accident when some of the liquid scintillator material (highly toxic) got into the local ground water.

      Who knew particle physicists were such a kinky bunch?

      --
      Tags != Comments, and -1 (Troll) != -1 (I Would Respond Angrily To This Poster So They Must Be Trolling)
  7. neutrinos have three states? by Anonymous Coward · · Score: 0

    Sounds suspiciously like a qubit. Perhaps the universe is a quantum computer afterall!

    1. Re:neutrinos have three states? by Anonymous Coward · · Score: 0

      I second that.

  8. Oops! My bad! by siglercm · · Score: 3, Interesting

    Well, I guess if you're dogmatic about a subject, you should expect to blow your whole leg off someday....

    This is the first story of Roland's that, in my opinion: 1.) Isn't blog whoring (no link back to ZDnet blog, although his home page _is_ pri - midi); and 2.) Is a story of real scientific interest; and 3.) Isn't terribly mis-represented in his summary. So even _I_ won't tag this story.... Isn't that ironic? Don't 'cha think?

    It surprises me how a scientific blogger could get the minor, or sometimes major, technical details of the story he posts about wrong, but at times Roland will. But not this time :^) Good story, Roland!

    --
    sigfault (core dumped)
  9. Re:Low post rate? by Anonymous Coward · · Score: 0

    Natalie Portman pours hot neutrinos down my pants...?

  10. No, parent poster was correct by Flying+pig · · Score: 4, Interesting
    And in my view insightful rather than funny. Al Gore was a political proponent of the Internet. But the concept of the www (which is just one of the many services running on dat ole Internet)did indeed originate in CERN.

    People often suggest on /. that progress on the Internet is driven by the needs of pornographers. But it would be interesting to know how much progress in networking and databases is actually driven by the (huge) data recording and analysis needs of particle physicists. My own interest in operating systems,networks and databases was started by the need to log large amounts of data very fast from lightning strike simulation experiments.

    --
    Pining for the fjords
  11. Re:Low post rate? by red_flea · · Score: 1

    Well we've heard of neutrinos before, and we know what they are. But they're so cutting edge, that I'd wager most of us are shrugging our shoulders, saying "Cool" and scrolling on.

    It's also so cutting edge that practical applications for results of this research are a long way off, meaning political arguments can't proceed about which congressmen and women are taking bribes from industries that will lose money if this stuff takes off in the US. Give it time tho; we'll comment after somebody figures a way to make tons of energy from neutrinos.

  12. Neutrinos massless = timeless, but change state? by elmartinos · · Score: 2, Insightful

    Last time I have heard something about the Neutrinos, there was an unresolved problem: Neutrinos do not have mass, therefore travel at the speed of light. But since they travel at the speed of light they have no sense of time, and therefore it should not be possible for them to change their state as they are practically frozen in time. This and earlier experiments confirm that despite that they change state. Are there already theories why this is possible?

  13. Totally gnarly! by fractalboy · · Score: 0

    The article failed to mention that detection of the Neutrinos was aided by the fact that they were joyriding around Dimension X in a flying car.

    1. Re:Totally gnarly! by harrkev · · Score: 1

      No no no.

      They were in the 8th dimension, and they developed their own oscillation overthruster, which they used to escape.

      On a more serious note, the tags for this article seem rather negative about Roland Piquepaille. Can anybody explain this? Is he an accomplice of Hans Reiser or something?

      --
      "-1 Troll" is the apparently the same as "-1 I disagree with you."
    2. Re:Totally gnarly! by Anonymous Coward · · Score: 1, Informative

      His submissions range from deceptive and misleading to plain old wild speculation. This seems to be a first for him, a story that is straightforward, belongs on slashdot and doesn't link back to his blog. It should really be tagged 'bravoroland' or 'abouttimepipsqueak'.

  14. Re:Oops! My bad! by aicrules · · Score: 4, Informative

    Not so fast! Try taking a drink from the firehose on this one. You'll see that while the main link is still there, he DID include a link back to ZDnet that got edited out!

  15. Re:Neutrinos massless = timeless, but change state by Anonymous Coward · · Score: 3, Informative

    You have correctly stated the problem, and the solution is that they must have some mass. There are several experiments underway to measure what their masses are. They are very tiny, probably sub-eV (for reference, the electron has mass of 511,000 eV. and the proton has mass 938,000,000 eV).

  16. Re:Neutrinos massless = timeless, but change state by Angstroman · · Score: 5, Informative

    Indeed, the presumed oscillations imply that the mass of the neutrino is small, but not zero. See, for example http://focus.aps.org/story/v2/st10 for a good discussion. Getting a good experimental measure of the mass of a particle that interacts so weakly with detectors has been a very long running challenge in experimental physics.

  17. Finally, low calorie neutrinos. by Anonymous Coward · · Score: 1, Funny

    I love neutrinos, but my doctor said I shouldn't eat them. With new low-energy neutrinos, I can have some without the guilt - - and without my doctor hounding me.

    1. Re:Finally, low calorie neutrinos. by zCyl · · Score: 1

      I love neutrinos, but my doctor said I shouldn't eat them.

      It's quite alright. They go right through you.
  18. Anything like High Energy Protons? by Anonymous Coward · · Score: 0

    spilling over into our atmosphere?

    1. Re:Anything like High Energy Protons? by Anonymous Coward · · Score: 0

      Everything is going extremely well

  19. Re:Oops! My bad! by Anonymous Coward · · Score: 2, Interesting
    You'll see that while the main link is still there, he DID include a link back to ZDnet that got edited out!

    Well then, my compliments to kdawson for showing the way and doing some actual editing.

  20. Low-Latency, Direct Communications by TheLazySci-FiAuthor · · Score: 4, Interesting

    I'm going to wax somewhat sci-fi here and imagine that detection in real-time of neutrinos might have potential application in regards to communication tech.

    In my view I see the ability to detect neutrinos as the first step towards a truly peerless communication system. Imagine that instead of radio waves one were to use neutrino emissions for communication. There would be no (or very little) interference (pass straight through any material) and subsequently the latency of communication from any point on the globe would be decided by the diameter not the circumference of the com point's positions on the earth - meaning that communication delays would be greatly reduced.

    Imagine if any communications device could simply connect directly to any other device on the planet at low-latency with high-signal strength - wouldn't that be neat!

    1. Re:Low-Latency, Direct Communications by ErikZ · · Score: 2, Funny


      I know! I was looking at this the other day: http://apod.nasa.gov/apod/ap990623.html

      And that just screams "Portable antenna"

      There's no way to grab neutrinos man. The reason there's no interference in neutrino transmission, is because nothing can block it/pick it up.

      --
      Democrats or Republicans. They are both taking us to the same place and they are not afraid of us anymore.
    2. Re:Low-Latency, Direct Communications by TheLazySci-FiAuthor · · Score: 1

      That's the beauty and the bane about neutrinos, isn't it? No interference in transmission, and yet no way to detect them as a result. But here in this article they explicitly say "real-time" detection.

      To me, that is the first step. There must be a way to grab these damn useful phantom particles :)

    3. Re:Low-Latency, Direct Communications by Anonymous Coward · · Score: 1, Informative

      Well, problem is... look at what's needed to detect 'em: a HUGE detector mass! (huge amount of target matter).

      I'm afraid that will definitely rule out portable devices... 8-)

    4. Re:Low-Latency, Direct Communications by tqft · · Score: 1

      have thought about this.

      You owe me a copy of next book for this idea

      coupled quantum oscillators - you want the pair to have similar but slightly diff frequencies (sub-eV diff equivalent in energy) and the both need to be very stable - the neutrinos then interact with the frequency difference and show up as a perturbation in one or both of the oscillator systems.

      Hope you prefer replies to mod points.

      --
      The Singularity is closer than you think
      Quant
    5. Re:Low-Latency, Direct Communications by ErikZ · · Score: 1

      I have no idea if what you describe works, or is even possible.

      But it would be sweet if it is.

      --
      Democrats or Republicans. They are both taking us to the same place and they are not afraid of us anymore.
    6. Re:Low-Latency, Direct Communications by tqft · · Score: 1

      The problem is amplifying the perturbation to detectable in the coupled oscillators without destroying the signal or the oscillators - at sub-eV levels it will tough.

      Phase locked quantum oscillators are actually reasonably well studied even though the classical case (and the quantum case) both are tough problems it has been studied - particularly in the area of "Chaos" theory - basically you dump the noise into the environment away from your signal/detector setup

      --
      The Singularity is closer than you think
      Quant
  21. Re:Oops! My bad! by siglercm · · Score: 1

    "Try taking a drink from the firehose on this one."

    Thanks, but my firehose drinking days are over. Last time I tried it, I got plastered against a brick wall. The back of my head hit first. Not fun. ;)

    "You'll see that while the main link is still there, he DID include a link back to ZDnet that got edited out!"

    Then I agree with the AC who replied to you, saying, "my compliments to kdawson for showing the way and doing some actual editing." Roland isn't very reformed, but the /. editor(s) are. I, for one, welcome our new Roland-blog-post-editing /. editors....

    --
    sigfault (core dumped)
  22. Secret underground Lie Detector by Temujin_12 · · Score: 1

    The Borexino lie detector almost a mile underground near L'Aquila, Italy
    I'd hate to wake up finding myself there.
    --
    Faith is a willingness to accept something w/o complete proof and to act on it. Reason allows you to correct that faith.
  23. It's about time. by GigG · · Score: 2, Funny

    Thank God, we will finally be able to track the Romulans when they are cloaked.

    --
    Is buying a Harley Davidson as your first motorcycle since you were 16 at age 49 a midlife crisis issue?
    1. Re:It's about time. by ultranova · · Score: 1

      In Soviet Russia, the Sun shines on you !

      --

      Forget magic. Any technology distinguishable from divine power is insufficiently advanced.

    2. Re:It's about time. by cadeon · · Score: 1

      The thing's gotta have a tailpipe.

    3. Re:It's about time. by iago-vL · · Score: 1

      Speaking of "It's about time", I was starting to get worried that nobody was going to make a Star Trek reference!

  24. geometric nature of reality by Gearoid_Murphy · · Score: 2

    I'm not a physicist but I find such oscillatory behavior fascinating. The first person (as far as I'm aware) to really push geometric relationships of a space as a means to explain its dynamics was Clifford. Einstein went a step further and provided a brillant and comprehensive explanation of the gravity/time/mass/energy relationships as the geometric nature of the space time continuum (correct spelling). Since there are still some really strange anomolies in physics (wave/particle duality for one), its interesting to see strange spatial characteristics manifested by the behavior of a particle/wave (neutrino) moving in a straight line.

    --
    prepare the survey weasels.
  25. Late News for Nerds by toddhisattva · · Score: 1

    I already heard this on hate radio last Friday!

    Though it was pronounced "new-try-noes" so maybe that was about a different particle.

  26. Re:Neutrinos massless = timeless, but change state by rasputin465 · · Score: 2, Interesting

    Neutrinos do not have mass.... therefore it should not be possible for them to change their state

    Actually, that's the whole thing... these experiments which show that neutrino flavor oscillates are evidence that neutrinos DO have mass (and also, don't travel at the speed of light).

    But the fact that a particle travels at the speed of light doesn't necessarily mean it can't change state. It's true, a photon would not be able to measure the passage of time, but stationary observers like us can measure the passage of time as a photon travels at a finite velocity through the lab. E.g., photons CAN change state (and they are massless).

    The reason that neutrino oscillations prove that neutrinos have mass is a little more subtle. We already knew there are three "flavor" neutrino states (electron, muon, tau), which we thought were fixed. But if a neutrino oscillates between these, that requires that a neutrino is actually a linear combination of these three states, and hence there must exist a separate basis of neutrino states which ARE fixed. The only way to do that is if these separate three states are mass states, which must be fixed because of conservation of energy. So, a neutrino is created in the sun with a definite mass state and possibly definite flavor state, but as it travels the mass cannot change, and so the flavor must oscillate. A similar relation between mass and flavor exists for the quarks.

  27. Earth Nuke? by toddhisattva · · Score: 1

    When I was growing up, there was a theory that at the center of the Earth is a natural fission pile heating the place up. Makes the continents move.

    The experiments of the time, however, did not detect the expected number of neutrinos from that direction. (It was known from human reactors that fission spits neutrinos.)

    Now that we know neutrinos have a tiny mass, and are therefore not moving at the speed of light, and therefore they experience time, and therefore they can and do oscillate ---

    Do these findings at all bring new life to the Nuke at the Center of the Earth theory?

    1. Re:Earth Nuke? by habig · · Score: 1

      Do these findings at all bring new life to the Nuke at the Center of the Earth theory?

      The Borexino results do not, but a similar experiment in Japan called Kamland has seen these geo-neutrinos:

      http://www.physorg.com/news5491.html

      Borexino should also be sensitive to them, but I don't think they've put out a paper on them yet, as the real-time 7Be neutrino detection was the New News.

  28. Re:Oops! My bad! by Mr.+Underbridge · · Score: 5, Funny

    Well then, my compliments to kdawson for showing the way and doing some actual editing.

    Today's weather forcast calls for airborne swine throughout the country, and a blizzard localized to Hell.

  29. Re:Low post rate? by Gilmoure · · Score: 1

    I turn 40 in a couple months. Have to have my postrate examined. Bleah!

    --
    I drank what? -- Socrates
  30. Re:Neutrinos massless = timeless, but change state by Anonymous Coward · · Score: 0

    To pose some obvious follow-up questions...

    Why are we so sure that photons are massless? Is it something just assumed, or has it been measured? Has it been measured accurately enough?

    Obviously, photons move at the speed of light (by definition). But if they too have 'immeasurably small', not 'zero' mass, that has some rather interesting implications for physics, does it not?

    Has anyone looked for similar alternative states in photons?

  31. Re:Oops! My bad! by nospam007 · · Score: 1

    This is the first story of Roland's that, in my opinion: 1.) Isn't blog whoring (no link back to ZDnet blog, although his home page _is_ pri - midi); and 2.) Is a story of real scientific interest; and 3.) Isn't terribly mis-represented in his summary. So even _I_ won't tag this story.... Isn't that ironic? Don't 'cha think?
    --
    Perhaps because the story is not from Roland?

  32. Spoon by QuantumPion · · Score: 3, Funny

    In other news, CERN scientists stated that they would have detected 90% more neutrinos, except some jackass was playing an MP3 on the data collecting computer, which happened to be running Vista.

    1. Re:Spoon by Anonymous Coward · · Score: 1, Interesting

      Actually Borexino uses Debian Linux for both its data acquisition and data analysis systems.

      No Windows in Vista here @ LNGS! ;-)

  33. Re:Oops! My bad! by Eponymous+Bastard · · Score: 1

    Now if this keeps up I wonder if Roland will:
    -Keep submitting stories. (Reputation is good for business)
    -Go away. (No need to waste his time)
    -Send a C&D to slashdot and subsequently sue. (Editing his submission is clearly the creation of a derivative work and needs an additional permission from him to be distributed).

    Time for Taco to add an EULA where you state that your submission might be mercilessly edited.

  34. Re:Neutrinos massless = timeless, but change state by Anonymous Coward · · Score: 2, Insightful

    Why are we so sure that photons are massless? Is it something just assumed, or has it been measured? Has it been measured accurately enough?

    Obviously, photons move at the speed of light (by definition). But if they too have 'immeasurably small', not 'zero' mass, that has some rather interesting implications for physics, does it not? [Disclaimer: IAAP, although I don't work in this area.]

    Just to clarify, when you talk about photons having mass, you mean nonzero rest mass. Photons already behave in many ways as though they have mass because they have energy.

    I think the short answer is: if photons had mass, even small mass, then EM radiation would be dispersive in a vacuum, i.e., different wavelengths would travel at different speeds. I don't think this has been observed. A recent article did report something along those lines, but I didn't see any mention of nonzero-rest-mass photons as an explanation. Rather, they're interpreting the results as a possible verification of one of the predictions of string theory: that high-energy photons induce spacetime lensing that slows them down ever-so-slightly compared to their low-energy counterparts. Hey, who knows -- maybe someone could come up with a nonzero-mass photon theory to explain the results. Or maybe the string theorists are doing that already. I don't know -- like I said, I don't work in this area.

    Has anyone looked for similar alternative states in photons? See above.
  35. OT: Re:Totally gnarly! by andreyw · · Score: 1

    You're new here, right ;-)

    Just kidding.

    Roland has frequently in the past used Slashdot as a platform to popularize (and make money off) his blog.

  36. Geo-Reactors and Rogue Nukes by PsiStarPsi · · Score: 1
    Although this experiment alone may not shed much light on the geo-reactor theory, there are other proposals for neutrino experiments that may. For example, http://arxiv.org/abs/hep-ex/0609041 describes a proposal for a deep sea neutrino observatory which could be used to measure thorium and uranium concentrations in the core and mantle. It could also be used to test the geo-reactor theory:

    The second goal is a definitive search for a hypothetical nuclear reactor at Earth's core. This theory (Herndon 1996; Hollenbach and Herndon 2001) has not met wide acceptance by the geological community, who have generally preferred the idea that much of the U/Th rose from the molten, early inner Earth as slag, rather than sank to the core as elemental metal. Yet, many geologists say that there really is no evidence against the hypothesis since the conditions at Earth's formation are little known. Moreover, there are peculiarities in the isotopic content of Earth, and most particularly the observed high ratio of 3He/4He coming out of oceanic volcanic hot spots (such as Hawaii and Iceland), which a natural reactor could explain (3He would come from tritium decay, made abundantly in reactors). Slightly off the topic from geo-neutrinos, the same type of experiment could in principle be used to detect "rogue nuclear activity." Details available below. http://arxiv.org/abs/hep-ph/0607095
  37. Re:Neutrino jokes here: by StarfishOne · · Score: 1

    Perhaps Homer isn't even saying always "Do'h!", but "tau!" :p