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Comment Strong Magnets! (but only transient) (Score 1) 166

I used to work next to the french Laboratoire National des Champs Magnétiques Intenses (Powerful Magnetic Field National Laboratory) and was lucky enough to visit it once during the yearly Science Day (why don't we have this in the US?).

They claimed they had the second most powerful magnets in the world, IIRC behind the Fermilab, at about 32T (again, IIRC). Note that this is a sustained magnetic field, not transient as the OP's record. (still, hitting 100T without destroying the magnet is one hell of a feat! Now if only we could find a source of power to sustain such a field...).

32T is extremely high, more powerful than any natural magnetic field on Earth (according to WP, the Earth's field is about 25uT at the equator to 65uT at the poles). The most powerful permanent magnets (rare-earth) can achieve a little under 1T, and good luck getting that magnet off a piece of steel. 32T is achieved only in a space about the size of 2 coke-cans at the center of a large cylindrical apparatus that is the concentric electromagnets. But even at such a strength, the fields we make are dwarfed by stellar and interstellar magnetic fields, that have been calculated to reach hundreds or thousands of Teslas.

Fun facts: they run the magnets at night, when power is significantly cheaper. They have big banks of capacitors and batteries for spare surge power. The (classical) electromagnets aren't built by spooling wire on a tube, because wire isn't thick enough the sustain the kind of current that goes through. Instead they take a thick copper tube that they slice in a spiral and insert an isolator in the spacing.

Their most powerful magnets were formed of a core superconducting electromagnet surrounded by standard electromagnets. The cost of superconducting materials is what prevent them from making more powerful stuff.

But despite all that, I'm still not sure what kind of experiments require such powerful magnetic fields. Such awesome engineering, so few applications...

Comment News isn't the soldering, but the OSS libraries (Score 4, Interesting) 240

The fact that they won't deliver in kit isn't news*, it's more interesting to know that they have HW-accelerated versions of MPEG4 and H.264 (and only those), and that all these libraries are closed source.

Furthermore, claims that they have the fastest mobile GPU are fluff: we only have the subjective word of someone who worked on it, not a neutral 3rd party, and it'll be caught up by someone else soon anyhow.

Finally, I'm going to advance that any complaints about the nvidia binary driver are going to be small fry compared to Broadcom's drivers.

*it's just not possible to hand-solder BGA packages. At best you'd need a reflow oven, and *that's* still tricky with the sizes involved here.

Comment Simtec "Entropy Key" also does quantum RNG (Score 4, Interesting) 326

A while back, the Simtec Entropy Key was making the rounds among Debian Devs, and claims to be exploiting quantum effects in the P-N junctions to be a true RNG.

They seem serious and I tend to trust paranoid Debian developers' opinions, but ultimately I don't have enough knowledge myself to make a confident judgment call. I'd be curious about more opinions.

Comment Other things Slashdotters would agree with (Score 1) 2247

"Cuts of this scale will also be accomplished by a Paul Presidency abolishing the Transportation Security Administration and returning responsibility for security to private property owners, abolishing corporate subsidies, stopping foreign aid, ending foreign wars, and returning most other spending to 2006 levels."
Source, his campaign website

I'll scream bloody murder for abolishing the Dept of Education and Energy, but I can see where Ron Paul-supporters are coming from.

Comment Still more interesting than Facebook (Score 1) 519

As others have commented, Facebook probably has less than 40% active users. But that's not what keeps me on G+.

I use it as a sort of augmented twitter, Following a bunch of science bloggers I find interesting (Shared Circle). It started out as a small list from Maggie Koerth-Baker, the science blogger at BoingBoing, and slowly accumulated more people through recommendations (network effect!).

Nowadays, Facebook is for the silly friends' stuff, but G+ is slowly turning into a major science news source populated by authors I respect.

Comment Re:This is what easy over safe design gets ya (Score 1) 205

I really, really hate what Gigabyte does with their BIOSes, considering their BIOS backed itself up on the end on some of my disks, changed the OS-visible size of the disk using Host Protected Area (HPA), squashing the mdraid metadata that was happily living there.

By the time I understood what was happening, I had had 3 of my 6 RAID disks screwed, as I had swapped the disks around ignorantly thinking it was some controller error.

That feature was not advertised, and that version of the BIOS had a bug where this feature didn't properly detect which disks it could accomplish this on (it only looked for NTFS/VFAT partitions, natch) and could not be disabled. While I can understand the purpose and usefulness of the feature, releasing with such a bug has made me swear off Gigabyte.

For the reference, it was a GA-P35-DS3, with BIOS F12.

Comment Marlinspike's approach (Score 5, Interesting) 163

Marlinspike's approach, implemented in a Firefox extension presented at DefCon '11, is to do away with the notion of CAs altogether in SSL, replacing it with a distributed network that reports on the certificate they see. Basically, if the certificate you see agrees with the rest of the network, then you're not being spoofed.

He had previously explained the properties a replacement to the CA system had to demonstrate in order to be viable

Comment breaks HDCP, not AACS (Score 5, Insightful) 1066

People are confusing this master key that breaks HDCP, saying it can help decrypt Blu-Ray discs. That's not the case: Blu-Ray is encrypted with AACS, which has a similar concept of device keys derived by a master key. AACS has a mechanism of revoking compromised device keys. Getting the AACS master key would bypass that mechanism, and would be great news.

This key isn't the AACS master key This is an HDCP key, which would allow one to create a "unauthorized" device that can connect to HDCP-encrypted HDMI and succesfully decrypt the HD stream.

HDCP has been known to be nearly broken since 2001, in that obtaining the device keys of 40-50 devices is enough to calculate the master key.

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