Slashdot Mirror
Building the World's Most Powerful Laser
Bill writes "Lawrence Livermore National Laboratories is attempting to create the world's largest laser. The NIF's goal is to focus the laser on a pea-sized hydrogen pellet and result in fusion ignition."
It is not readily mountable on a shark's head.
Nah, it's not even a little scary. Fusion is quite unlike fission, in that it's really hard to get going and just as hard to keep going.
With fission, all you have to do is put too much Uranium (or Plutonium or whatever nasty, radioactive stuff) in a closet, and it will spontaneously sustain itself in a "chain reaction". If you put way too much stuff in the closet, then the chain reaction runs away and explodes, spontaneously.
With fusion, you take a tiny sphere of deuterium (or tritium) and blast it for a tiny fraction of a second with the World's Largest Laser Beam. If you are really, really lucky, the deuterium will fuse to helium and you'll get out a little bit more energy than you spent getting the thing to fuse. There's no possibility of a runaway here, because there's no chain reaction. You can simply choose not to fire the WLLB at any point.
Liberal (adj.): Free from bigotry; open to progress; tolerant of others.
The term "ignition" refers to the point of intensity of a fusion reaction whereby the high (kinetic) energy He nuclei fusion product is sufficient in power to heat any remaining fuel to the point of fusing itself. ie. when the reaction is capable of sustaining itself provided you continue to feed it with fuel. It is called Q=1. The NIF should achieve >Q=10 on a full system DT shot and this is called thermonuclear ignition and burn with "high gain". NOTE! the NIF will almost certainly NOT achieve breakeven (total power in Nd:glass lasers are disgustingly inefficient (~1%). Diode pumped Nd:glass is another story however and if a power plant is ever to be constructed using laser fusion then that is likely what will be used. They are still too fantastically expensive today though.
- "Hear that?! The percolations are imminent! Cease your ingress!"
Ok, ok. I totally got this reference right away. Which maybe dates me a bit (I'm under 30).
:-)
A few people will usually get it. But the majority will say something amazingly stupid.
But what makes that movie (and that scene) so special?
Oh, come on! That's the ultimate 80's party movie for geeks! They pulled off all sorts of geeky pranks (dry ice in the hall, disassembling/reassembling a car in the dorm, tuning a radio to braces), saved the world through some pretty creative hacking/espionage, and even pulled an awesome prank on the bad guy! What's not to like?
Group think. Meh, original scenes make group think happen because the group remembers them.
Ummm... no. Group Think refers to the Slashdot mentality of accepting the story spin at face value without checking the facts. A perfect example was the Chase Mastercard story from a day or two ago. The poster said "wireless", "RFID", and "insecure", thus ensuring that 95% of the posts were "This sucks and is insecure wireless crap that I can hack like this RFID hack (some pointless link here)!" The truth of the matter was that the card was not wireless (induction), not RFID (smartcard), and was not insecure (crypto chip). It was actually a marked improvement over the current cards! And yet, the last response to my rebuttals of such nonsense still had someone calling it wireless and insecure! Enough to make me want to drop-kick a few people...
Javascript + Nintendo DSi = DSiCade