admiral_ju00

bleh. damnit, i will turn in my request for the Nature subscription!!! but here's what i found googling for: quantum entaglement Quantum Entanglement In 1935 and 1936, Schrödinger published a two-part article in the Proceedings of the Cambridge Philosophical Society in which he discussed and extended a remarkable argument by Einstein, Podolsky, and Rosen. The Einstein-Podolsky-Rosen (EPR) argument was, in many ways, the culmination of Einstein's critique of the orthodox Copenhagen interpretation of quantum mechanics, and was designed to show that the theory is incomplete. In classical mechanics the state of a system is essentially a list of the system's properties — or, more precisely, it is the specification of a set of parameters from which the list of properties can be reconstructed: the positions and momenta of all the particles comprising the system. The dynamics of the theory specifies how properties change in terms of a law of evolution for the state. Pauli characterized this mode of description of physical systems as a ‘detached observer’ idealization (see Pauli's letter to Born in The Born-Einstein Letters, p. 218). On the Copenhagen interpretation, such a description is not possible for quantum systems. Instead, the quantum state of a system should be understood as a catalogue of what an observer has done to the system and what has been observed, and the import of the state then lies in the probabilities that can be inferred (in terms of the theory) for the outcomes of possible future observations on the system. Einstein rejected this view and proposed a series of arguments to show that the quantum state is simply an incomplete characterization of the system. The missing parameters are sometimes referred to as ‘hidden parameters’ or ‘hidden variables’ (although Einstein did not use this terminology, presumably because he did not want to endorse any particular ‘hidden variable’ theory). It should not be supposed that Einstein's definition of a complete theory included the requirement that it be deterministic. Rather, he required certain conditions of separability and locality for composite systems consisting of separated component systems: each component system separately should be characterized by its own properties (even if these properties manifest themselves stochastically), and it should be impossible to alter the properties of a distant system instantaneously (or the probabilities of these properties) by acting on a local system. In later analyses — notably in Bell's extension of the EPR argument — it became apparent that these conditions, suitably formulated as probability constraints, are equivalent to the requirement that statistical correlations between separated systems should be reducible to a common cause in the sense of Reichenbach. In the original EPR article, two particles are prepared from a source in a certain quantum state and then move apart. There are ‘matching’ correlations between both the positions of the two particles and their momenta: a measurement of either position or momentum on a particular particle will allow the prediction, with certainty, of the outcome of a position measurement or momentum measurement, respectively, on the other particle. These measurements are mutually exclusive: either a position measurement can be performed, or a momentum measurement, but not both simultaneously. Either correlation can be observed, but the subsequent measurement of momentum, say, after establishing the position correlation, will no longer yield any correlation in the momenta of the two particles. It is as if the position measurement disturbs the correlation between the momentum values. The puzzle is that the quantum state of the particle pair is inconsistent with any assignment of precise position and momentum values to the particles separately. These values would be the common cause of the correlations, and would provide an explanation of the correlations in terms of the initial correlations between the properties of the two systems at the source. EPR concluded that the quantum state was incomplete. Here is how Schrödinger put the puzzle in the first part of his two-part article (Schrödinger, p. 559): Yet since I can predict either x1 or p1 without interfering with the system No. 1 and since system No. 1, like a scholar in an examination, cannot possibly know which of the two questions I am going to ask first: it so seems that our scholar is prepared to give the right answer to the first question he is asked, anyhow. Therefore he must know both answers; which is an amazing knowledge; quite irrespective of the fact that after having given his first answer our scholar is invariably so disconcerted or tired out, that all the following answers are ‘wrong.’ What Schrödinger showed was that if two particles are prepared in a quantum state such that there is a matching correlation between two ‘canonically conjugate’ dynamical quantities — quantities like position and momentum whose values suffice to specify all the properties of a classical system — then there are infinitely many dynamical quantities of the two particles for which there exist similar matching correlations: every function of the canonically conjugate pair of the first particle matches with the same function of the canonically conjugate pair of the second particle. Thus (p. 559) system No. 1 ‘does not only know these two answers but a vast number of others, and that with no mnemotechnical help whatsoever, at least with none that we know of.’ Schrödinger coined the term ‘entanglement’ to describe this peculiar connection between quantum systems (Schrödinger, p. 555): When two systems, of which we know the states by their respective representatives, enter into temporary physical interaction due to known forces between them, and when after a time of mutual influence the systems separate again, then they can no longer be described in the same way as before, viz. by endowing each of them with a representative of its own. I would not call that one but rather the characteristic trait of quantum mechanics, the one that enforces its entire departure from classical lines of thought. By the interaction the two representatives [the quantum states] have become entangled. He added (Schrödinger, p. 555): Another way of expressing the peculiar situation is: the best possible knowledge of a whole does not necessarily include the best possible knowledge of all its parts, even though they may be entirely separate and therefore virtually capable of being ‘best possibly known,’ i.e., of possessing, each of them, a representative of its own. The lack of knowledge is by no means due to the interaction being insufficiently known — at least not in the way that it could possibly be known more completely — it is due to the interaction itself. Attention has recently been called to the obvious but very disconcerting fact that even though we restrict the disentangling measurements to one system, the representative obtained for the other system is by no means independent of the particular choice of observations which we select for that purpose and which by the way are entirely arbitrary. It is rather discomforting that the theory should allow a system to be steered or piloted into one or the other type of state at the experimenter's mercy in spite of his having no access to it. In the second part of the paper, Schrödinger showed that, in general, a sophisticated experimenter can, by a suitable choice of operations carried out on one system, steer the second system into any ‘mixture’ of quantum states he chooses, i.e., not steer the system into any one particular state, but constrain the state into which the system evolves to lie in a given set, and at the same time fix the probabilities with which the system evolves into the states from the given set. He found this conclusion sufficiently unsettling to suggest that the entanglement between two separating systems would persist only for distances small enough that the time taken by light to travel from one system to the other could be neglected, compared with the characteristic time periods associated with other changes in the composite system. He speculated that for longer distances each of the two systems might in fact be in a state associated with a certain mixture, determined by the precise form of the entangled state. Most physicists dismissed the puzzling features of entangled quantum states as an artefact of Einstein's inappropriate ‘detached observer’ view of physical theory, and regarded Bohr's reply to the EPR argument as vindicating the Copenhagen interpretation. This was unfortunate, because the study of entanglement was ignored for thirty years until John Bell's reconsideration and extension of the EPR argument. Bell looked at entanglement in simpler systems than the EPR case: matching correlations between two-valued dynamical quantities, such as polarization or spin, of two separated systems in an entangled state. What Bell showed was that the statistical correlations between the measurement outcomes of suitably chosen different quantities on the two systems are inconsistent with an inequality derivable from Einstein's separability and locality assumptions — in effect from the assumption that the correlations have a common cause. Bell's investigation generated an ongoing debate on the foundations of quantum mechanics. One important feature of this debate was confirmation that entanglement can persist over long distances(see Aspect et al.), thus falsifying Schrödinger's supposition of the spontaneous decay of entanglement as two entangled particles separate. But it was not until the 1980s that physicists, computer scientists, and cryptographers began to regard the non-local correlations of entangled quantum states as a new kind of non-classical resource that could be exploited, rather than an embarrassment to be explained away. (For further discussion of entanglement as a physical resource, including measuring entanglement, and the manipulation and purification of entanglement by local operations, see "The Joy of Entanglement" by Popescu and Rohrlich in Lo, Popescu, and Spiller, or Nielsen and Chuang.)

well, for about 18(US) bucks, you can get the full document detailing the whole thing.....

1) Photoshop. 2) Some links give you a downloadable vid, some don't. never really tried to investigate it, so dunno why that's so.

yeah, which species are you thinking of? (i'm pretty sure they all have it though)

Nice idea, and since the current market is saturated with programmers, network engineers and other techies, this(assuming more schools pick up on it) will do good to both the IT industry and Science.

funny, and a very good idea. j/k

oh i believe that he still holds the title of the most notorious hacker ever. he has recently been released from prison after he decided to break into a few systems, gave FBI a run for their money, bleh, blah, bleh here's some info on the matter...... http://www.takedown.com/bio/mitnick.html

It probably is, and I think you're placing your trust a bit too much into this one book, that has even not been accepted by the majority of geologists and or anthropologists.

Well, humans are quite a bit older than 10,000 years, but there were NO such societies. That would mean that this society must have been the 1st to develop agriculture and the earliest evidence of that goes back some 7,000+ years ago. No I've not heard that, but it does not sound right. At least the date is not right. The most advanced (sea worthy) society I know of goes back to 3-4,000 years ago and that is when the Asians spread out through the Polynesia - Polynesian migration. There are lots of evidence for this, plus an mtDNA research to concur that.

i love the fact that the original poster is no longer here to defend his/her position, or propose a new theory......

i do not agree, err, i hate the fact that most recent flavours of linux are gearing more towards the X windows system and i will not use one. hence the reason why Slackware is still much more difficult for a novice user, then something like RedHat.

damnit, i should have read the post #32, but if you're reffering to this: contain DNA which provides inheritable genetic traits as the definiton for RNA then, no.

yeah. {edit} but since you question the very many basic things of biology, perhaps you can elaborate on this?

yub yub, commander in the USA, now, well since 9/11, you can easily attract FBI on your case doing this and upto 5years in jail or something. heh, i installed back orifice on all my (1st) university's libriary computers(and a few other things). i was really, really wanting the access to their LexisNexis, which worked to an extent, 'till i realized i've done it in a very sloppy fashion so, yeah, i had go and undo some of the things..... like i said, before it hits 18, it's all goooooooooooooooood timeeeeeeeees i dunno if you guys know or have heard of him, but my hero during those days was Kevin Mitnick.

what about it?

a long, long time ago, in a galaxy far away, i started out as a script kiddie, i then graduated to a much more developed hacker. after turning 18, i could NOT afford to do any jail time, hence i had to give up my bad habits but at times, i still miss all the fun things i did.......

Why don't you try running Linux/Unix on a PC as opposed to a Mac. You'll see the difference. What??? What??? Well, you know, if the system is not set right, then it'll be buggy...... No, at least not all of them. For me, when I was doing C and C++, I loved the ability to be able to modify any part of the OS I wish. Try doing that on Windows

-Physics/Cosmology http://www.motionmountain.net - Online (Free) Book Elegant Universe The Tao of Physics -Evolution: Origin of Species - C. Darwin Red Queen - Matt Ridley

damn, i miss my home town of NYC while i took the bio regents now over 6 years ago, it was a fun test.

http://javascript.internet.com/ http://www.javacoffeebreak.com/tutorials/ <- better linky

java

well, that link has an end to the loop, so eventually you'll get out of it. i did it a few times. and one time i was extremely bored, i actually read the entire thing this guy had there. lol, that took away 20 minutes of my life i'll never be able to recover. but also pressing and holding the Enter/Return button will get you out since it'll keep on clicking OK...... well for Java Script, you don't need any programs(i think), but for Java, you'll need to either download or buy one. although i haven't seen a free version of Java.

well, i take it you went to that link. (it does no damage, just annoys you). but, you can either do what that site does and you have to fulfil the reqs of the code(clicking OK till it finishes it's message) or create a loop w/ in a loop, with nothing to break(terminate) the cycle.

no, most likely it was Java or Java Scrypt very similar to: Weird Stuff Linky