Talk:Shiva laser

Latest comment: 16 years ago by Mcswell in topic Added link to Shiva Star

Some misconceptions I removed

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Shiva, like all large ICF lasers now (probably) used A regen amp. but not for the main amplifier chains. the regen is used to create the seed pulse only. The beamlines on shiva were single pass only. all ICF lasers up until NIF used the single passthrough beamline architecture. there are no reflecting cavities or multipass beams except on the NIF beamlet and on NIF itself. also shiva didn't compress liquid hydrogen. it compressed dt gas to equivalent liquid hydrogen densities. also it is important to understand that it is not the shockwave alone which is launched into the target that is noteworthy but the tremendous "shove" of compression from ablation which achieves the high densities. the shockwave and the compression should be thought of as separate. this is where the work on "shock-to-bang timing" comes in. it should also be understood that the term spatial filter means litteraly the whole assembly of a pipe. that is a big pipe with a lens on the end that focuses light down through a tiny pinhole at the center of the pipe where it expands outward again to be collimated by another lens at the opposite end of the pipe. --Deglr6328 06:01, 7 October 2006 (UTC)Reply

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I added a link down at the bottom to the Wikipedia article on Shiva Star (unfortunately, I wasn't logged in, but it was me :-)). My main reason for doing so was not that the two projects were closely linked (I don't know one way or the other), but the resemblance of names might lead someone to come to one expecting to find the other. Mcswell (talk) 13:48, 29 September 2008 (UTC)Reply

Etymology

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Though probably somewhat trivial, but I believe the naming of Shiva is not due to the multi armed nature of either Shiv the Hindu deity or the multi-beamed structure of the laser.

Shiv was known for his third eye which was placed on his forehead and was vertical and closed normally. Its opening signified the end/transformation and anyone who was viewed by Shiv with his third eye would be incinerated instantly. I believe in naming the laser Shiva, its power was compared with the mythical power of Shiv's third eye.

I tried finding some justification for its naming on the LLNL website but could not find anything. Definitely not the multi-armed logic.

From a different perspective, Shiv was never really known for his multiple arms as much. In fact most images and sculptures of his show two arms and two limbs. The depiction of Shiv as Nataraja, the eternal dancer does show him with multiple arms, but that too often is as an visual effect for his dancing speed creating an illusion of multiple arms.

In the hindu holy trinity Shiv played the role of the destroyer or transformer and was said to possess endless power in his third eye.

The correlation of power seems a more rational reason behind naming the laser Shiva rather than the multi-armed nature.

I would be curious about the source of the multi-armed explanation. And I mean sources which are not blogs, which are not news stories referring to the wiki article, not lecture-notes at various universities which have no connection with LLNL. A correct source would be either the LLNL site or some scientist who worked on the original design.

And quite interestingly, the Lasers which preceded Shiva were called Cyclops and Argus. All three names borrowed from various mythologies, but having an underlying theme of eyes. Cyclops had one eye on his forehead, Argus was covered with eyes and Shiva has the powerful third eye.