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Comment: Re:Don't know if what you say is true ... (Score 1) 136

by stoborrobots (#49178241) Attached to: Photo First: Light Captured As Both Particle and Wave

I don't think the term is quite that bad, but the way we talk about it is. That said, my choice to use the term "puff" was specifically to avoid any pre-conceived notions about the duality.

The term "wave-particle duality" was coined because we can imagine waves, and we can imagine particles, and when we realised that we couldn't force light and electrons to be one or the other, that they must be, in some sense "both".

The term is not wave particle alternation, conversion, collapse, or any thing which implies that it is sometimes one and sometimes the other. However, the elementary examples we give people learning about QM might mislead people to believe that.

The "duality" is expressed specifically to indicate that it has both aspects at all times.

Comment: Re:not the first time (Score 1) 136

by stoborrobots (#49177183) Attached to: Photo First: Light Captured As Both Particle and Wave

Close - you're mixing up the wavefunction of a puff of light with the wave-like nature of a puff of light.

The wavefunction gives you the probability distribution of any properties you want to measure.

The wave-like nature is what gives it colour and allows diffraction.

But the wave-like properties (wavelength, etc) are not the properties of it's position wavefunction.

You make reference to the electron double-slit experiment. It's tempting to think that electrons are particles - except that they're not. The fact that they exhibit the same "particle-wave duality" indicates that they too are "puffs" of matter, not particles, not waves, but something with properties of both.

There are no particles at quantum scale. Particles only exist at human scales. The struggle comes in accepting that the thing we are talking about is not analgous to any specific thing in our experience. It's convenient to talk about particles, and waves, because we can conceive of what they are. We imagine that particles are like incredibly small billiard balls, and waves are like ripples on a pond and that light is sometimes one and sometimes the other - because we can imagine these things. But puffs of light and puffs of matter don't behave like tiny billiard balls or tiny ripples - they behave like a combination of them. You can simultaneously measure both wave-like and particle-like behaviour.

Comment: Re:not the first time (Score 5, Informative) 136

by stoborrobots (#49167423) Attached to: Photo First: Light Captured As Both Particle and Wave

The wave-particle duality is not a quantum superposition like you're describing (which would break down under measurement), although the caricatured manner in which we teach it might lead you believe that. It's a little more simple than that.

In our world, we are used to two kinds of things: particles, and waves. We are used to this distinction, and describe most things in one of these manners. Sound is a wave, a billiard ball is a particle, vibrations are waves, bricks are particles. If something is a particle, it has certain properties, like position, size, and shape. If it is a wave, it has certain other properties like wavelength, frequency, and amplitude. In addition, there are some common properties like velocity and direction.

When it came to studying light (and many other quantum stuffs), we can't directly see what it's made of. But we can take measurements of each "puff" of light, and infer its properties that way. When we do this, we notice that puffs of light have some properties which are particle-like, and some which are wave-like. So the term "particle-wave duality" became popular to describe this new material that was behaving simultaneously like a particle and a wave. It doesn't make sense to ask which one it is - a "puff" of light is neither a particle, nor a wave, but a different kind of stuff which has some properties of each.

Comment: Re: [1]=overhead? Not always (Score 1) 520

by stoborrobots (#49084951) Attached to: Nim Programming Language Gaining Traction

If you're storing the length, then "iterate over array and perform this operation" (for example, for a search or a "double every element" transformation) can use the known length to set up a for loop, rather than having to check "am I at the last element of the array" for every element... This could be a good reason to store the length even if you don't want the cost of bounds-checking.

+ - Hackers take banks to the cleaners for at least $300 Million->

Submitted by jjoelc
jjoelc (1589361) writes "In a highly sophisticated attack, hackers struck over 100 different banks over the course of nearly two years making off with at least $300 million, though Kaspersky Labs estimates the true total could be 3 times that. Getting a total is difficult not only because of the scale of the attack, but because transactions were never more than $10 million, though some banks were hit more than once.
“This is likely the most sophisticated attack the world has seen to date in terms of the tactics and methods that cybercriminals have used to remain covert,”
The hackers spent months monitoring infiltrated systems, learning the routines of the bank involved. When it came time to cash out varying methods were used including account transfers to dummy accounts and causing ATM machines to dispense cash at scheduled times. The largest sums were taken by gaining access to the banks accounting systems and artificially inflating an account balance, then quickly transferring the excess balance to a dummy account."

Link to Original Source

+ - AT&T To Match Google Fiber in Kansas City, Charge More If You Want Privacy-> 1

Submitted by Anonymous Coward
An anonymous reader writes "When Google Fiber started bringing gigabit internet to cities around the U.S., we wondered how the incumbent carriers would respond. Now we know: AT&T has announced they will match Google Fiber's gigabit offerings in Kansas City. Of course, there are some caveats. First, AT&T's rollout may stop as it fights the Obama administration over net neutrality. Not that it would be a nationwide rollout anyway: "AT&T does not plan to offer the ultra-fast Internet lines to every home in the market. Rather, he said the company would calculate where demand is strongest and the investment in stringing new cables promised a decent return."

There are also some interesting pricing concerns. The company plans to charge $70/month for gigabit service, but that's a subsidized price. Subsidized by what, you ask? Your privacy. AT&T says if you want to opt out of letting them track your browsing history, you'll have to pay $29 more per month. They say your information is used to serve targeted advertising, and includes any links you follow and search terms you enter."

Link to Original Source

Comment: Re:Nonsense (Score 1) 411

by stoborrobots (#49045351) Attached to: Your Java Code Is Mostly Fluff, New Research Finds

I agree with you on the idea and behaviour of the control classes, but have generally found it handy to have some guarantees of well-formedness in the data objects.

Otherwise, every control object which uses the data object needs to verify every detail about the data object before it uses it - which leads to the duplication of validation code issue you were concerned about in the first place...

Comment: Re:Nonsense (Score 1) 411

by stoborrobots (#49044315) Attached to: Your Java Code Is Mostly Fluff, New Research Finds

So if you are not doing your field validation at creation time, how do you enforce the "interface contract"?

Something somewhere has to verify that the address is a valid address, and the port is a valid port (why would you accept a socket request for port 67890?) - why allow a non-conformant data object to exist?

What domains have such wide-ranging field values that validated data is not a reasonable idea?

Comment: Re:Nonsense (Score 1) 411

by stoborrobots (#49036469) Attached to: Your Java Code Is Mostly Fluff, New Research Finds

Data classes like this?

class TCPSocketAddress
private long ipaddress;
private int port;
string getAddress()
  return long2ip(ipaddress);
void setAddress(string addr)
  if (addr.matches("/^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3)$/")) ipaddress = ip2long(addr);
  else throw InvalidIPAddressException;
int getPort()
  return port;
void setPort(string addr)
  if (newport > 0 && newport < 65536) port = newport;
  else throw InvalidTCPPortException;

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