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World's Most Powerful Laser
mattlary writes "The Rochester Democrat and Chronicle reports that the University of Rochester plans on building the world's most powerful laser. The plans include upgrading the University's Omega laser with a pair of petawatt lasers. Sounds a lot like Real Genius to me."
It's great that the first sharks post always gets modded way up... but really. Do we need to see the exact same comment on every LASER story?
Also, Kent gave it to me in the pooper last night.
...that laster the US defense dept. has that they have used to shoot down projectiles with? Could this possibly be used and in part funded by the defense dept.? The next evolutionary step for military lasers?
In order to start a fusion reaction, you must reach these incredible temperatures.
For H-bombs, the idea is to use a fisson bomb to kick-start the whole thing.
Now they are trying to build fusion reactors, and obviously using fission power is not that popular (the whole point is to get rid of the problems of fission).
Using extremely powerful and focused lasers seems to be the best idea as yet. This is only needed to start the reaction, once it has started it is kept alive by its own power and a supply of hydrogen.
Tor
A watt is a unit of power, not energy.
This laser (I can tell you without reading the article, as the laws of physics prevent the presumption) is only on for an EXTREMELY short duration, probably on the order of billionths of a second (that's 10E-9, for UK readers).
A peta-joule (as someone else pointed out) would be a LOT of coal. A petawatt for an extremely short duration isn't that much energy. Probably less than the entire university consumes for 1 second (I don't have accurate numbers on their power consumption, so don't micro analyze this statement).
The only use for such a short duration but high power laser is in physics experiments, and typically involves only a few dollars of electricity, so nearly no appreciable amount of coal or waste of any kind.
I'll pass on the political discussion though.
but how the hell can they harness that
In a word, magnets. The idea behind fusion, essentially, is that you raise a (hydrogen) plasma to sufficient temperature and pressure, and it will undergo fusion. If you get the conditions just right, it'll then continue to fuse once you've ignited it, thus supplying you with energy.
What you may not appreciate is that a plasma is electrically charged, and can therefore be contained using a suitable magnetic field. Arguably the most promising containment setup at the moment is the tokamak (from the Russian for bottle, iirc), which is a torus-shaped machine. Electromagnets around the torus create a circular magnetic field, which keeps the plasma contained in a ring. (My apologies if my information is out of date, I quit my PhD in plasma physics 4 years ago...)
Despite what the article says, however, fusion is not entirely pollution-free. One of the byproducts is a fairly large supply of neutrons. These neutrons are absorbed by the reactor, which will slowly but surely become radioactive. Therefore, you will eventually be left with radioactive waste to dispose of. You won't get anything like the quantity you get with fission, though, and fusion certainly doesn't produce any "conventional" pollution.
It's official. Most of you are morons.
The energy used in this laser, as you said used "in a very short burst", would power a city, although just for a few milliseconds. Multiply that by the thousands of people in the city and you may not even have enough electricity to run my webserver for ten seconds (slashdotted or not). Warm those without roofs? What powers the sun? And what are the researchers trying to produce? Fusion. And what does the sun do? Even if you are an idiot the answer is warm us. So the researchers are investing money and power to hopefully make large advances in WARMING THE ROOF-LESS.
Have you ever read the artical? Ever?
We're only gonna die from our own arrogance, that's why we might as well take our time...
This isn't really news, being that the Vulcan laser in the UK reached petawatt capacity some months ago, after being awarded a grant for the purpose four years ago (see here) - the article doesn't mention the exact capacity, but I don't imagine that it's much more than a petawatt.
Another important thing to mention - again, not having read up on this - is that most scientific lasers are single-shot; most lasers are femto or petasecond lasers. From the same site as above (different news item, "Over the course of the three year upgrade project, the output of Vulcan's ultra-short pulse beam will be increased to 500J in a pulse of 500fs duration giving a power on target of 1 Petawatt (1015 Watts)" - for many purposes, a laser such as Astra suits many peoples purposes; whilst the pulse energy for astra is
As far as military applications are concerned, as mentioned in other threads, this laser would almost certainly be useless; it would be far too hard to aim, and in any case, lasers like this reach sufficient power that they require nitrogen-filled tubing in many laboratories in order not to ionise the air under certain circumstances (which creates irritating popping noises) - there are certain other technical details (such as the beam type) which render them inefficient for military purposes (although one scientist working with astra and vulcan did want to shoot a beam into space with an encyclopedia encoded in the beam pulse in order to transmit data to potential victims of human first contact).
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Speaking of RG, I found out a couple weeks ago that MIT was showing this at the frosh weekends. WTF? The movie is completely based on Caltech, their rival. Just about every inside joke comes from good ol' Pasadena. They don't call it "Pacific 'Tech" for nothing.
Anyways, they show it (rightfully) at CIT prefrosh weekends, so maybe the kids'll be smart enough to figure it out for themselves.
... then they decide to dump money into the physics program instead of the Rochester Strong Medical Center.