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Comment More info about NIF - Start Trek connection (Score 2) 252

Seeing a lot of discussion, but not much real information here, so I'll contribute.

For starters, here is the website: https://lasers.llnl.gov/

And here is a page of that site that has some explanation about how it works: https://lasers.llnl.gov/programs/nic/icf/how_icf_works.php

I've actually toured this facility, and it was pretty damn cool. A few points that stuck in my memory:

The generally do one shot each night. They prep it during the day, then they all go home and it goes off at night with not many people there, because that's safer.

The electricity usage is intense but very short, lasting only around 20 billionths of a second. They do this by charging up their capacitors and then discharging them very rapidly. They said the air conditioning for the building actually uses more power than the laser.

They talk about the "seven wonders of NIF", which are seven advances in materials and technology that were made during the project which made it all possible. I thought the rapid crystal growing was pretty wicked. Info on them here: https://lasers.llnl.gov/about/nif/seven_wonders.php

In the actual ignition step itself, while you might think you shine the powerful laser on the thing you want to heat up, that's actually not how it works. They have the thing they want to heat, and near it (like 1mm) is this little metallic trough thing. They blast the laser into the trough thing and when the light hits that it creates microwaves, and the microwaves heat the target. Of course by the time it's done all those parts are completely vaporized.

Also of interest, around April this year the place was shut down for maintenance for a month. For about two weeks during that period some filming for the next Star Trek movie took place inside the NIF facility. So check out the pix and see if you can spot the NIF scenes when the movie comes out. It does kinda look like the engine room of a starship: https://lasers.llnl.gov/multimedia/photo_gallery/target_area/?id=5&category=target_area Obviously, the whole lab is full of nerds who like Star Trek, but they were not allowed to see what was going on.
Shark

Record Setting 500 Trillion-Watt Laser Shot Achieved 252

cylonlover writes "Researchers at the Lawrence Livermore National Laboratory's National Ignition Facility (NIF) have achieved a laser shot which boggles the mind: 192 beams delivered an excess of 500 trillion-watts (TW) of peak power and 1.85 megajoules (MJ) of ultraviolet laser light to a target of just two millimeters in diameter. To put those numbers into perspective, 500 TW is more than one thousand times the power that the entire United States uses at any instant in time."

Comment Re:There is value in "shallow" learning (Score 2) 166

Agreed.

There is great value in knowing which things we (i.e. humanity and the scientific community) understand and which we don't. To me this is the primary message and the joy of reading/listening to Feynman. Over and over again he sketches out what we understand in a field and then highlights the questions that remain, and shares his enthusiasm and wonder for those unanswered questions that are waiting out there for a sharp mind grasp. This focus on the unanswered question is what makes his work so inspirational. It makes you want to become a physicist so you can go out and solve some of those mysteries. And that also is what differentiates Feynman's approach from how science is taught in most places. It's taught with a focus on what we know, which unintentionally gives the student the impression that we mostly understand things, which is completely wrong.

On another note, as a computer scientist and architect of large systems, it is important for me to know what is do-able and what is not, which problems we have solutions for, which are intractable nonstarters, and which we have a chance to solve in the right situation with the right brainpower applied. The details of why are less important. For example, I don't need to understand deep crypto to know what we can encrypt the comms between these two components. I know it's a solved problem, what it can and cannot do, and that's all that matters to me. Put it in my toolbox along with sorting, hash tables, full-text indexing, AJAX, machine learning, and hundreds of other techniques, each of which is its own deep field, and I can use this knowledge to design systems with high confidence that they are going to work as planned.

Comment Re:Dear Slashdot, (Score 2) 166

...published in the 1960s and I don't think have ever really been brought up to date...

They have been updated. From wikipedia: "Also released in 2005, was a "Definitive Edition" of the lectures which includes corrections to the original text."

And the Amazon page says: "The revised edition of Feynman's legendary lectures includes extensive corrections and updates collated by Feynman and his colleagues. A new foreword by Kip Thorne, the current Richard Feynman Professor of Theoretical Physics at Caltech, discusses the relevance of the new edition to today’s readers."
Medicine

Submission + - People Born With Certain "Personality Genes" May Live Longer (medicaldaily.com)

An anonymous reader writes: People who are outgoing, optimistic, easygoing, and have a good sense of humor and a large social network are likely to live longer than others who don't possess these personality traits, according to new research.

The study reveals how saying "It’s in their genes" could refer to more than just genetic variations that give a physiological advantage like having high levels of HDL ("good") cholesterol because people with positive personality traits appear to live longer than those who do not.

Comment Re:I knew freedom had a price.... (Score 1) 527

Freedom isn't free! It cost folks like you and me.
And if we don't all chip in, we'll never pay that bill.
Freedom isn't free! No there's a hefty fucking fee.
And if you don't throw in your buck o'five who will?

If you don't throw in your buck o'five who will?
Ooh... buck o'five

Freedom cost a buck o'five

(please visualize this sung by marionettes.)
Parker and Stone 'Putting The "F" Back In Freedom'

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