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Creating a Quantum Superposition of Living Things

KentuckyFC writes "Having created quantum superpositions of photons, atoms, and even molecules, scientists are currently preparing to do the same for larger objects — namely viruses. The technique will involve storing a virus in a vacuum and then cooling it to its quantum-mechanical ground state in a microcavity. Zapping the virus with a laser then leaves it in a superposition of its ground state and an excited one. That's no easy task, however. The virus will have to survive the vacuum, behave like a dielectric, and appear transparent to the laser light, which would otherwise tear it apart. Now a group of researchers has worked out that several viruses look capable of surviving the superposition process, including the common flu virus and the tobacco mosaic virus. They point out that after creating the superposition, scientists will be able to perform the Schrodinger's Cat experiment for the first time, which should be fun (but less so for the virus)."

37 of 321 comments (clear)

  1. Viruses don't live by tsa · · Score: 3, Informative

    Viruses are not living things. They have no metabolism and need a host to reproduce. They're basically just packets of proteins containing DNA.

    --

    -- Cheers!

    1. Re:Viruses don't live by gestalt_n_pepper · · Score: 4, Insightful

      Oh please. They're self-replicators in the domain of organic chemicals. They take resources from their environment (i.e. DNA), effectively use those resources for self-replication, and manage to do this with just enough random noise for adaptive mutation to occur.
      .
      That's more than I can say of certain slashdotters living in their mother's basements. Are you saying that they're not alive?
      .
      Let the debate begin!

      --
      Please do not read this sig. Thank you.
    2. Re:Viruses don't live by koterica · · Score: 4, Interesting

      Parent is correct: Biological viruses are like complex SQL injections that cause the host software to send out copies of the injection code. However, they are not executable on their own.

    3. Re:Viruses don't live by Permutation+Citizen · · Score: 4, Funny

      Sure. That's why we call them "no-life".

    4. Re:Viruses don't live by RandomFactor · · Score: 3, Funny

      They're only MOSTLY dead!

      --
      --- Mercutio was right.
    5. Re:Viruses don't live by Anonymous Coward · · Score: 4, Insightful

      I don't think there's much of a debate. It's common consensus that virii sit on the border being alive. They have most of the traits of what is usually defined as being alive, but they don't have all of them. The technicalities aren't terribly important in any context, including the philosophical one, so nobody really bothers.

    6. Re:Viruses don't live by Unordained · · Score: 5, Interesting

      Oh? Just the other day, we were talking about how much cell division is like fork(): it's not just the pure code that's forked, but the state of all globals and open file descriptors, too. There's more to reproduction than just our DNA, there's all that "running VM" stuff going on, too: an infected cell that reproduces is likely to result in two infected cells, even if that's not part of the cell's normal DNA; a cell with a chemical imbalance will likely pass that on to its new sibling. Some cloning methods rely on injecting one cell's DNA into another -- like running a program in both a test and production environment, care should be taken to think about the whole situation when diagnosing problems, not just the DNA/code itself. See? More similarities.

      Comparing & contrasting (via "like") is not the same as saying the two are the same (via "equals"). Commonalities, when they can be found, are informative because (most) humans have the power of inductive reasoning. You're welcome to point out the important differences so we can avoid coming to undue conclusions in one or the other field.

    7. Re:Viruses don't live by Vellmont · · Score: 4, Insightful


      The question of whether viruses are living things is far from clear-cut.

      The question of whether viruses are alive or not is as interesting a question as whether submarines swim. (To steal a phrase for Dijkstra).

      We know what viruses do and don't do. Arguing about whether they're "alive" or not is purely semantics and is not a scientific question at all.

      --
      AccountKiller
    8. Re:Viruses don't live by Tom · · Score: 3, Funny

      We know what viruses do and don't do. Arguing about whether they're "alive" or not is purely semantics and is not a scientific question at all.

      But it's important! See, this 4th level AD&D spell affects, according to its definition "all living things within 5 feet of the target position". I must know whether it'll wipe out a virus! The fate of the world depends upon it!

      --
      Assorted stuff I do sometimes: Lemuria.org
    9. Re:Viruses don't live by IICV · · Score: 5, Informative

      You know what else is common consensus? The plural of "virus" is "viruses".

  2. I implore you, by palegray.net · · Score: 3, Funny

    won't someone think of the viruses? I'm going to pen a letter to the Amercian Society for the Prevention of Cruelty to Microscopic Organisms That May Or May Not Be Alive immediately!

    1. Re:I implore you, by Red+Flayer · · Score: 5, Funny

      Amercian Society for the Prevention of Cruelty to Microscopic Organisms That May Or May Not Be Alive

      The ASPCMOTMOMNBA?

      You, sir, need to work on your organization names.

      Let me suggest a few:

      The Society for the Prevention of Cruelty to Questionable Under Examination To Zoological Life Characterization Organisms Almost This (.) Large.

      The SPC-QUETZLCOATL is, of course, dedicated to the humane treatment of viruses, and should not be confused with the SPCQ, which is dedicated to the humane treatment of feathered-serpent redeemer/savior archetypal figures.

      Also it should be noted that the (.) in the official name of the organization is a tiny dot in parentheses, not a ASCII boobie, no matter how much you'd like it to be one.

      --
      "Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
  3. Hasn't Schrodingers Cat been through enough? by TheRealPacmanJones · · Score: 4, Funny

    We are still experimenting on this mans cat after all these years? Im surprised PETA isnt all over this...

    --
    Don't try to be a great man. Just be a man, and let history make its own judgment - Zemfram Cochrane
    1. Re:Hasn't Schrodingers Cat been through enough? by Anonymous Coward · · Score: 4, Funny

      Are you sure about that? I am pretty sure the cat died years ago, but I haven't checked.

  4. Uh oh! by Anonymous Coward · · Score: 4, Funny

    The virus will be both dead and alive! So this is how the zombie plague will begin...

  5. There is only... Super Virus! by spun · · Score: 4, Funny

    Seriously, people, anyone who has read comic books knows that strange scientific experiments involving lasers, quantum mechanics and viruses can only lead to an acute case of superheroitis.

    --
    - None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
    1. Re:There is only... Super Virus! by severoon · · Score: 3, Funny

      Great, now I have to hear my doctor say, Um, it seems you completed the full course of antibiotics...but it turns out it only attacked the inert state of your disease. The virulent, flesh-eating superposition continues unchecked.

      --
      but have you considered the following argument: shut up.
    2. Re:There is only... Super Virus! by Martin+Blank · · Score: 4, Interesting

      Virii is not a word. The plural is 'viruses.'

      Whether viruses are life is still a matter of some debate. They have genes, reproduce, and evolve, but have no metabolism of their own and do not reproduce by division. They require a host cell in order to reproduce, but so do some bacteria. It's a fuzzy line.

      --
      You can never go home again... but I guess you can shop there.
    3. Re:There is only... Super Virus! by Anonymous Coward · · Score: 5, Funny

      Virii is not a word. The plural is 'viruses.'

      If that's true, then what are infecting my boxen?

    4. Re:There is only... Super Virus! by osu-neko · · Score: 3, Informative

      If we pull a DNA strand out of a nucleus from one of your cells and put it on a plate, it is not a living thing. It remains true that if we put it back undamaged, it can then reproduce, but it's still just a DNA fragment.

      If we are to say viruses are living things, it would imply that that DNA fragment is a living thing.

      Also, we've been on a crusade recently to taxonomically reclassify everything based on its evolutionary history, now that our understanding of DNA enables us to determine this. Since viruses, being leftover DNA or RNA fragments from the breakup of expired bacteria for the most part, they don't have an evolutionary history per se. They don't fit into the taxonomic classes for living things anywhere. A severed or left-over part of a living being is not, in an of itself, a living being, no matter how it behaves when you reattach or reinsert it into one.

      --
      "Convictions are more dangerous enemies of truth than lies."
  6. Reckless world-line creation! by argent · · Score: 3, Funny

    Since the collapse of the state vector is an illusion caused by the entanglement of the experimenter with the experiment, whereupon the experimenter (now in a superposition of states) can only measure one outcome, this recless creation of macromolecular superpositions will deplete the multiverse's supply of world-lines and immanentize the eschaton. We'll have doppelgangers racing madly through the streets, and it will all end in tears.

    1. Re:Reckless world-line creation! by jollyreaper · · Score: 5, Funny

      Since the collapse of the state vector is an illusion caused by the entanglement of the experimenter with the experiment, whereupon the experimenter (now in a superposition of states) can only measure one outcome, this recless creation of macromolecular superpositions will deplete the multiverse's supply of world-lines and immanentize the eschaton. We'll have doppelgangers racing madly through the streets, and it will all end in tears.

      Seems no less reasonable than the wiki writeup on superposition. QM reads to me like high-brow White Zombie lyrics, just words rammed together with no inherent meaning. Stick a few "motherfuckers", "yeahs" and obscure movie quotes in there and I think we'd have it. I'm sure it makes sense to some people but I'd need a contact high to grok it.

      THE DEAD HAVE COME BACK TO LIFE!The Hamiltonian gives the rate at which the particle has an amplitude to go from m to n. YEAH! The reason it is multiplied by i AMBIENT SCREAMING SOUNDSis that the condition that U is unitary translates to the condition: YEAH MOTHERFUCKER YEAH! which says that H is Hermitian. The eigenvalues of the Hermitian matrix H are real quantities which have a physical interpretation as energy levels. PSYCHOLOIC SLAG SUCKING JUICE FROM A FALLEN ANGEL If the factor i were absent, the H matrix would be antihermitian and would have purely imaginary eigenvalues, which is not the traditional way quantum mechanics represents observable quantities like the energy.INSANE CLOWN LAUGHTER

      --
      Kwisatz Haderach
      Sell the spice to CHOAM
      This Mahdi took Shaddam's Throne
  7. Re:Scale to larger living things? by eldavojohn · · Score: 3, Funny

    I'm not certain that this technique will scale to cats.

    Don't worry, the next step up from viruses are lawyers. Since they have to put them in a vacuum and hit them with a laser, line 'em up and put it on Youtube ... in the name of science!

    --
    My work here is dung.
  8. The researchers who work with viruses disagree by JoshuaZ · · Score: 5, Informative

    A lot of the researchers who work with viruses consider them to be alive. See for example this piece by Abbie Smith explaining why viruses should be considered to be alive and why most of the arguments against are not convincing: http://scienceblogs.com/erv/2009/03/ten_five_reasons_clumsy_excuse.php. The people who argue that viruses aren't alive are almost inevitably non-biologists or biologists who don't work with viruses.

  9. Is this necessary? by Robert1 · · Score: 4, Interesting

    I was under the impression that there was nothing to be gained by doing the schrodinger's cat experiment. The idea is that in collapsing the probability wave of any object, the "observer"-object (really anything that the collapsing object interacts with, conciousnes not required!) essentially becomes a superposition of states. This forms an outward expanding wave of super position with the individuals caught within the wave observing it as collapsed and those outside the event observing all those that interact with the superpositions becoming superpositions themselves.

    For example scientist-A is in an isolated box and has a cat in an isolated box. The cat is a superposition either dead or alive, is definately one or the other when he opens the box. Let's say for him, the cat is dead when he opens it and that makes him sad. However the scientist-B, outside the larger box which contains scientist-A can now say that the box is filled a superposition of A-with dead cat (sad scientist), and A-with live cat (happy scientist). This is because scientist-B does not know the result of scientist-A opening the box,only that room now contains a superposition of a sad or happy man with a dead or live cat. Only when B opens this larger box does it the superposition of A collapse for scientist B. Now B is in the same position - he is now be a superposition of states of scientist-B seeing sad-man with dead cat, and scientist-B seeing happy-man with live cat. So the idea is that ALL quantum events function in this way. Performing this on any object, be it virus or molecule or cat. Of course because the real world has no such isolation boxes, these wavefronts of collapse and local superposition happen continuously and undetectably.

    So what will happen is they'll go through all this difficulty to superpose two states. Then view the virus, seeing it in one state - all the while oblivious that they are now intertwined with that superposition to an outside observer.

    1. Re:Is this necessary? by clone53421 · · Score: 4, Funny

      To an outside observer, I am now in a superposed state of understanding and totally not understanding your comment...

      --
      Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
  10. Schroedinger's cat? by kinnell · · Score: 3, Interesting

    Surely all you need to perform the Schroedinger's Cat experiment for real is a box, a cat and a radioactive substance which decays into a poison. I thought the whole idea of superposition is that the object is simultaneously in multiple states until you observe it, at which point it is in a single state. If they can observe something in different states simultaneously, doesn't that debunk the whole theory? If they can't then what is the point of the experiment? My layman's knowledge of quantum physics is obviously lacking. Could someone explain?

    --
    If I seem short sighted, it is because I stand on the shoulders of midgets
    1. Re:Schroedinger's cat? by blueg3 · · Score: 4, Interesting

      No, a real cat and a real box are too tightly coupled to the rest of the world to actually create a superposed state. The common layman's understanding treats a superposition as sort of an "I don't know" state, but that's not accurate. If you made a Schrodinger's cat-killing box, certainly you wouldn't know if the cat was alive until you opened the box, but you wouldn't end up constructing a superposed quantum state.

      One consequence of a superposition being a real state (rather than an "I don't know") is that you can perform tests that show an object must have been in a superposed state, beyond simply opening many cat-boxes and observing that half are dead and half are alive. It's fair to call this "observing that the object is in a superposed state", but it conflicts with the quantum-mechanical definition of "observation" that involves collapsing the wavefunction. They certainly can't quantum-mechanical-observe the superposed state directly -- but that's not what they're saying.

    2. Re:Schroedinger's cat? by osu-neko · · Score: 3, Informative

      Another issue is that a cat can't be alive and dead, only one or the other. Just because YOU don't know which, doesn't mean that it doesn't, or that reality doesn't. [...]

      Yes, that was once a common philosophical view of reality, but it's one that's flat out contradicted by observation. I'm ignoring the errors in the rest of your post since it all seems to follow from the above false statements.

      --
      "Convictions are more dangerous enemies of truth than lies."
  11. Wrong field by gmuslera · · Score: 3, Funny

    With the Schroedinger cat you didnt know if it was alive or dead in the physical experiment. But biology has decided yet if virus are alive to start it? What will be the next thing they will use for this test? a meme?

    1. Re:Wrong field by sbillard · · Score: 3, Insightful

      I could be wrong, but I think the point of the experiment is to learn where and how quantum aspects interface with macro-objects. A virus is much larger than a photon, for example. If they can reproduce "delayed choice" and "quantum eraser" type effects on a virus, then that would really be something.

      It's not a test to see whether something is alive or dead. It's a test to understand if and/or how "which-path" observations collapse the wavefunction for macro-objects,

      IANAP, so please enlighten me if I missed the point.

  12. Re:that's not the point by clone53421 · · Score: 3, Funny

    it's not less alive, per-say, than a single celled amoeba or an atom

    Wut?

    --
    Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
  13. Terrible idea by DoofusOfDeath · · Score: 4, Funny

    I can see it now...

    Me: Tell me Doc, do I have HIV?
    Doctor: Well, yes and no.

  14. Re:That's how I pick up chicks by Chris+Burke · · Score: 3, Funny

    "This is amazing! I'm coming/not-coming at the same time!"
    "Nice try. I observed you ejaculating three seconds into it."

    --

    The enemies of Democracy are
  15. You know what I can't stand about Slashdot? by wonkavader · · Score: 5, Funny

    The smell, if there is such a thing. I feel saturated by it. I can taste the Slashdotters' stink and every time I do, I fear that I've somehow been infected by it.

  16. It's semantics, so debate is pointless by Radhruin · · Score: 3, Interesting

    The definition of life is somewhat squishy, even in Biological fields, but still, technically, viruses are not living as they do not exhibit many traits that living creatures do (eg. homeostasis, metabolism, growth, asexual or sexual reproduction, etc).

    In common language, and philosophically speaking, the argument for calling a virus living could be made, but it's all just semantics.

    Wikipedia has an interesting article on life and its varying definitions throughout time: http://en.wikipedia.org/wiki/Life

  17. Just What We Need by monopole · · Score: 3, Funny

    Schrodinger's Flu!