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Comment $10 / month, no contract. Read the summary (Score 1) 71

I know you liberals can't be bothered to actually read an article, but come on, the summary is just a few sentences.
After the six free months, it US $10 / month.

I've heard that Comcast sucks. If you think they do, you have two choices:
a) tell people why Comcast sucks
b) totally make shit up out of thin air, so readers think that people complaining about Comcast are liars and idiots

Comment only ones where they identified the children (Score 1) 790

The one used in this case is a database of in images where they know who the kids are. So not just "obviously underage", but "that's Megan Smith, who is 9 years old". More in info can be found here:
http://www.missingkids.com/CVI...

Other systems exist for "looks like probably". They are mostly useful when you don't want any porn, so Facebook and YouTube could use them. YouTube uses such a system as a pre-check, then has him humans manually confirm. At least, they DID. They could have stopped using it an hour ago and I wouldn't know.

Comment * emphasis on more bits (3DES) (Score 1) 80

I said:

> A DES-based hash would still be fine, just by allowing more bits.

I should clarify that DES itself specifies a key length of 56 bits. To get more bits, you do DES three times*, which is called Triple DES or 3DES. If you use three different 56-bit keys, that's effectively a 112 bit key due to meet-in-the-middle, and that's strong for an another fifteen years.

* encrypt(key1,decrypt(key2,encrypt(key3,plaintext)))

Comment Re:Sensationalism at its worst (Score 1) 201

Fact 3: You're talking about the Cannae Drive, not the EmDrive.
Fact 4: They (NASA Eagleworks) *ALSO* tested the EmDrive, and found that it produced approximately 91 microNewtons of thrust.
Fact 5: According to the inventor of the EmDrive (who is NOT the inventor of the Cannae Drive), the Cannae Drive (in either normal or "null" variant) is just an inefficient EmDrive.

Now, I'm not saying that the EmDrive guy (Shawyer) is right. But *YOU* are wrong. There is no conclusive evidence of a systematic error in NASA's experiment.
Ockham's Razor time: which of the following is more likely correct?
1) The inventors of the EmDrive (Shawyer) and the Cannae Drive (Fetta) are both correct that their drives produce thrust, but Fetta is wrong that the radial grooves (which the null test was lacking) are required, and Shawyer is correct that his version is more efficient (though his understanding of why may still be wrong).
2) Both inventors are completely wrong, the Chinese experiment is wrong, and the fact that all of the test devices produce detectable thrust in the appropriate direction regardless of which way they are pointed is a "a systematic error in NASA's experiment".

Option 2 doesn't sound "obvious" at all.

Comment Re:Ugh (Score 1) 201

Uh huh. Leaving aside the problems with everything you just said, what happens when you turn it over and get the same result? How about when you place it on its side and get the same result? Seriously, that's a pretty obvious null test. They thought of it.

Comment Re:Ugh (Score 1) 201

Actually, if it's proportional to the photon pressure, that's still pretty damn interesting... because the drive is *sealed*. There's nowhere for the photons to escape to. Light pressure is still an "equal and opposite reaction" deal. If microwave generation at one end of the chamber propels the drive one way, then microwaves impacting on the other end of the chamber ought to produce an equal propulsion the other way. Net thrust should be zero.

THE NET THRUST IS NOT ZERO! You appear to have completely misunderstood the design of the drive (not the supposed mechanism of it, the plain-English design). There's nowhere for photons, or ions, or electrons, or air molecules, or anything else to go. Either
A) point out where the exhaust of these things comes from
B) give a reason why they measured thrust when there actually wasn't any
C) stop calling things "IMPOSSIBLE" when they are, by multiple independently conducted experimental results, happening.

It wasn't that long ago that Newtonian mechanics were "among the best tested bits of physics". Relativity showed they were only an approximation of the truth, and that under previously-untested experimental conditions they were not accurate. I'm not saying that something similar is undoubtedly happening here, but I am saying that you're an idiot for claiming that it's impossible for "one of the best tested bits of physics" to be wrong under unusual situations.

Comment Re:Ugh (Score 1) 201

Sure, but it can't produce *consistently asymmetric* ones. If convection was responsible, than the *net* torque should have been zero since the entire system was sealed. Or rather, if it can, then hey, just make sure the drive container is full of air at atmospheric pressure when you mount it on your spacecraft!

Comment Re:Bad summary (Score 1) 201

That's not (necessarily) an "unexplained fault in the test apparatus", you idiot (speaking both to the AC and to the people who modded em up). That is an unexplained experimental result. How the fuck did at least four people, at time of writing, manage to get that wrong?

There were *THREE* test devices. (Seriously people, the summary and linked TFA sucks but what the fuck do you expect from /. anyhow? Do some further reading.)

Device 1: EmDrive, designed by Roger J. Shawyer. This is the same drive tested by the Chinese, though NASA ran the experiment at 1/50th the power of the Chinese experiment. The thrust produced per energy put in was far less than the Chinese reported, but it was non-zero. NASA apparently plans to test with a more powerful version of the drive (closer to the Chinese experiment).

Device 2: Cannae Drive (test article, as designed by Guido P. Fetta). This drive produced less thrust than the EmDrive but did produce some. Fetta claims that the drive requires "radial slots engraved along the bottom rim of the resonant cavity interior" in order to produce thrust. Shawyer claims that the Cannae Drive is basically just an inefficient EmDrive.

Device 3: Null version of Cannae Drive (lacking the slots, which Fetta says should mean no thrust but which are irrelevant to the supposed mechanism of the EmDrive). This version produced the same amount of thrust as the "real" Cannae Drive test device.

Comment Re:Bad summary (Score 1) 201

Why do you say "a version of the instrument"? There were two (non-null) test devices: an EmDrive and a Cannae Drive. According to its inventor, the Cannae Drive requires radial slots in the chamber and won't work without them. The EmDrive doesn't need such slots. According to the inventor of the EmDrive, the Cannae Drive is basically an inefficient EmDrive and the slots are irrelevant. To test the Cannae Drive (NOT the EmDrive!), a null version without the slots was tested as well.

Experimental result: All three devices produced thrust. The EmDrive produced more than the Cannae drive, but the Cannae drive produced the *same amount* of thrust whether it had the slots or not. That means Guido P. Fetta (inventor of the Cannae Drive) is wrong. It does *NOT* mean that Roger J. Shawyer, who invented the EmDrive, is wrong - in fact, to a degree it supports his claim that the Cannae Drive is just an EmDrive - although his own math is called into question by the low output even of the tested EmDrive.

Seriously, stop talking as if the inventors of Cannae Drive and EmDrive are the same group of people and believe that they work the same way. Fetta was shown to be flat-out wrong when the Null drive produced thrust too. Shawyer was shown to possibly be at least partly right (not proven, but not disproven either) when all three devices produced at least some thrust, and his produced more.

Comment Re:Carry the one (Score 1) 201

Do we know how careful the Chinese experiments were, relative to the NASA ones? Serious question, because yes, the difference *is* curious... but it's not necessarily due to one result being inaccurate. The experiments were not identical. NASA used much lower input energy, and a non-identical apparatus.

The expressing of thrust in terms of input energy (linearly) is weird and questionable for all the reasons you state. If thrust/energy does indeed remain constant regardless of velocity, then yes, that would appear to be usable for free energy. What this means is one of three things: 1) It doesn't, and we misunderstand the mechanism involved (since the latter half of that statement is almost certainly true, the first could be as well); 2) It does, but this doesn't produce free energy because our understanding of the physics there is wrong (unlikely but possible, if there is a thrust then it's caused by something our previous models did not account for and they only appeared to be accurate because of approximations at near-zero levels of this activity); 3) Free energy is possible after all, and everything that says otherwise is itself not entirely accurate).

By the way, you seem to have forgotten (or misunderstood) that there are multiple drive candidates being tested here. The null device producing thrust anyway indicates that the supposed mechanism of the second drive (the Cannae drive, *NOT* the EmDrive) is wrong. However, according to the inventor of the EmDrive, the Cannae Drive (with or without the slotting distinguishing the experimental and null devices) is basically an inefficient EmDrive. If the Cannae Drive does, in fact, produce thrust for the same reason that the EmDrive does (this assumes, as the experiment supports, that both drives produce thrust) then the supposedly-null device doesn't (dis)prove anything at all and needs no further explanation. Note that this doesn't require that the theories behind the EmDrive be correct, merely that they be less incorrect than the ones behind the Cannae Drive.

Don't get me wrong, I'm as skeptical as the physics as you are... but at the end of the day, the experimental result is what matters. The experimental result appears to disagree with your theories. Therefore, your theories appear to be wrong, or at least incomplete. What you *should* be doing is proposing modifications of your theories and ways to test their correctness. Proposing explanations for the experimental results that are consistent with the current theories (and ways to account for the discrepancy in future experiments) would also be valid. Saying "Nope, the math doesn't check out so it can't happen and anybody who says otherwise is a crank" is just flat-out bad science. We have an experimental result. The result is closer to what the alternative theory predicts than what your theory predicts. The burden is on you to explain that, if you want to maintain the current theory.

Comment Re:a bit of a copout (Score 2) 71

rather typical time-wasting stuff

WORLD STAR HIP HOP BOI !!!1

What might actually be nice would to see comcast

I've got a better idea. Put Comcast and all other ISPs in the Common Carrier category where they belong, break up Comcast and the rest of the oligopoly ISPs into small, regional companies limited with few exceptions to state lines, outlaw vertical ownership of both media and content, force the now tamed, small ISPs to wholesale their bandwidth to competitors and watch prices for bandwidth collapse to below the $10/month craptastic deal Comcast is supposed to be providing so that we may ALL partake in the benefits of competition we're supposed to be enjoying in a supposedly "capitalist" economy.

Because dealing with Comcast should be about more than buying votes with a wired manifestation of the Obama Phone.

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