I've been curious what is the justification for support of:
particles are in multiple simultaneous states until measured causing the distributed probabilities to collapse into a definite known state
over the seemingly more 'classical':
the particle has a definite position and momentum, but our measuring devices are too clumsy / interactive to measure one without affecting the other before another measurement can be made. For example if we measure something by zinging it with a photon and remeasuring the (same?) photon after it interacts with it, then it causes it to do something else before we can zing it again.
What you are suggesting is a hidden variables theory. Basically, each quantum particle should "know" the results of all possible measurements that someone might perform upon it, and act accordingly.
The problem is that experimental results rule out any "reasonable" hidden variables theory! For more information, check out the EPR Paradox and Bell's Inequality.
As far as we know nowadays, quantum entanglement can be used to transfer the quantum state of an atom (or an electron, or whatever) "instantly", but this cannot be used as a means of communication, because there is no way to measure an existing quantum states in its entirety. In general, measuring one part of the quantum state (e.g. whether the electron spins clockwise or counterclockwise with respect to a vertical axis) destroys all information about some other parts of the state (e.g. the spin with respect to a horizontal axis).
So - if you have two entangled electrons, you could measure the spin of one of them along some axis, and you would also know the spin of the other along the same axis. But this wouldn't enable the experimenter at one end to pick the result that the experimenter at the other end will measure.
Another spooky experiment that has been performed a few years ago is quantum state "teleportation". You have a pair of entangled electrons, and another electron which is in a generic quantum state X. You separate the pair and bring one of its electrons to another room. Then you perform a joint measurement on the two remaining electrons - and, "magically", the quantum state Y of the electron in the other room becomes "nearly the same" as the original state X. Meanwhile, the electron that originally had state X changes to a new state.
I write "nearly the same", since you need to take note of the result of the measurement, and then use it to apply a correction (by applying a "classical" magnetic field) to the state Y, in order to make it exactly the same as X. You need to transmit the result of the measurement by classical means, which means observable information is still bounded by the speed of light...
What makes you say that? MP3 files, and their ID3 tags, don't seem to be an issue really?
That's exactly my point. ID3 tags are standardized (ok, at least there is a standard subset of tags) and reflect objective characteristics of the tagged file (author, title, genre, and so on). It is perfectly fine for these tags to exist at file level.
User-defined information, on the other hand, should not be copied "by default" if you move the file to a different context.
Relational Database: A collection of "related" databases, for example and travel agent booking system consisting of customer, airline and account details, can be combined and would be referred to as a Relational Database.
I hope the author is just trying to dumbify the article for an audience of PHBs...
Adding flexible metadata at the level of files does not seem such a good idea to me, especially for files that need to be transmitted or shared with others. Catalogation systems are going to be different from user to user, and from organization to organization - which is going to be messy if you mix multiple systems together.
Having something like "post-it notes" that do not stick to the file, but instead are part of the directory entry for that file, might be more useful and safer. If someone sends me a file, I don't want that person's metadata to pollute my classification of files.
That's somewhat like what happens with e-mail - I receive plenty of mails that the sender marked as "high priority", but that are low priority to me.
Metadata on the file should be objective; subjective information should be stored somewhere else and not be transmitted together with the file.
In the past five years I've been working for a major consulting firm in Italy.
Every time one of my team members resigned, because they were moving, because they had found a better job, etc., they remained in the team long enough to wrap up their work and train their replacement. None of them lost their access until they actually left.
There are many reasons why we do this. First of all - when we say that we respect our colleagues, we mean it. When you know that you will be trusted with important issues until the last day, because you've seen it happen to others, you have an incentive to deserve that trust. It's quite good for morale.
Secondly, the risk of having a disgruntled employee messing up before he resigns (or not training his replacement properly) outweighs the risk of a respected, trustworthy, soon-to-be-ex-colleague committing sabotage after turning in his notice.
Third - our former colleagues often end up being hired by our clients in positions of responsibility. Keeping a good relationship with those who resign is good business sense: they might be the ones who decide whether to hire us a few years down the road.
So, Mike - your resignation was quite professional. If your former employer chose to act in a way that is likely to harm them in the long run... consider it a lesson learned.
By the way, IMO revoking access to employees during their notice period is a rather weak security practice. A good security policy protects your firm no matter whether the perpetrator resigned yesterday or will resign next year.
Copyright is meant to be a mutually beneficial agreement between society and authors - society grants authors an artificial monopoly on duplication of their works, so that authors are encouraged to create more.
In my opinion, the main problem with existing copyright law is that this artificial monopoly is granted automatically, and that its duration keeps increasing retroactively. I'm not talking about Mickey Mouse here - take the parent poster's comic strip for example. If in 2050 I wanted to distribute some copies, who knows if PCM2 will be around to grant me permission? So the current trend towards perpetual copyright makes sure that a large number of interesting creative works - those that are not profitable enough for the author or his heirs to care about in the long term - will become unuseable by law. This outcome is not "mutually beneficial" - the author does not gain anything, and society loses the opportunity for further use of the work.
If you want your works to be redistributable, possibly under some conditions, Creative Commons licenses are one way to patch this legal bug.
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What you are suggesting is a hidden variables theory. Basically, each quantum particle should "know" the results of all possible measurements that someone might perform upon it, and act accordingly.
The problem is that experimental results rule out any "reasonable" hidden variables theory! For more information, check out the EPR Paradox and Bell's Inequality.
So - if you have two entangled electrons, you could measure the spin of one of them along some axis, and you would also know the spin of the other along the same axis. But this wouldn't enable the experimenter at one end to pick the result that the experimenter at the other end will measure.
Another spooky experiment that has been performed a few years ago is quantum state "teleportation". You have a pair of entangled electrons, and another electron which is in a generic quantum state X. You separate the pair and bring one of its electrons to another room. Then you perform a joint measurement on the two remaining electrons - and, "magically", the quantum state Y of the electron in the other room becomes "nearly the same" as the original state X. Meanwhile, the electron that originally had state X changes to a new state.
I write "nearly the same", since you need to take note of the result of the measurement, and then use it to apply a correction (by applying a "classical" magnetic field) to the state Y, in order to make it exactly the same as X. You need to transmit the result of the measurement by classical means, which means observable information is still bounded by the speed of light...
That's exactly my point. ID3 tags are standardized (ok, at least there is a standard subset of tags) and reflect objective characteristics of the tagged file (author, title, genre, and so on). It is perfectly fine for these tags to exist at file level.
User-defined information, on the other hand, should not be copied "by default" if you move the file to a different context.
I hope the author is just trying to dumbify the article for an audience of PHBs...
Having something like "post-it notes" that do not stick to the file, but instead are part of the directory entry for that file, might be more useful and safer. If someone sends me a file, I don't want that person's metadata to pollute my classification of files.
That's somewhat like what happens with e-mail - I receive plenty of mails that the sender marked as "high priority", but that are low priority to me. Metadata on the file should be objective; subjective information should be stored somewhere else and not be transmitted together with the file.
Every time one of my team members resigned, because they were moving, because they had found a better job, etc., they remained in the team long enough to wrap up their work and train their replacement. None of them lost their access until they actually left.
There are many reasons why we do this. First of all - when we say that we respect our colleagues, we mean it. When you know that you will be trusted with important issues until the last day, because you've seen it happen to others, you have an incentive to deserve that trust. It's quite good for morale.
Secondly, the risk of having a disgruntled employee messing up before he resigns (or not training his replacement properly) outweighs the risk of a respected, trustworthy, soon-to-be-ex-colleague committing sabotage after turning in his notice.
Third - our former colleagues often end up being hired by our clients in positions of responsibility. Keeping a good relationship with those who resign is good business sense: they might be the ones who decide whether to hire us a few years down the road.
So, Mike - your resignation was quite professional. If your former employer chose to act in a way that is likely to harm them in the long run... consider it a lesson learned.
By the way, IMO revoking access to employees during their notice period is a rather weak security practice. A good security policy protects your firm no matter whether the perpetrator resigned yesterday or will resign next year.
In my opinion, the main problem with existing copyright law is that this artificial monopoly is granted automatically, and that its duration keeps increasing retroactively. I'm not talking about Mickey Mouse here - take the parent poster's comic strip for example. If in 2050 I wanted to distribute some copies, who knows if PCM2 will be around to grant me permission? So the current trend towards perpetual copyright makes sure that a large number of interesting creative works - those that are not profitable enough for the author or his heirs to care about in the long term - will become unuseable by law. This outcome is not "mutually beneficial" - the author does not gain anything, and society loses the opportunity for further use of the work.
If you want your works to be redistributable, possibly under some conditions, Creative Commons licenses are one way to patch this legal bug.