Archive for October, 2006

Attention mySql gurus!

Author: Cian

Please say you can answer this question

http://www.experts-exchange.com/Databases/Mysql/Q_22042592.html

I’m totally stumped, and need an answer soon, lest I redeign my db to not be normalized and say fuck it!!!!

UPDATE: Someone came up with the answer. For all you who were scratching your heads (I know there were a few…)

select *
from users t1
where exists (select 1 from groups g, user_groups ug where g.group_id = ug.group_id and t1.user_id = ug.user_id and g.group_name=’active’)
and exists (select 1 from groups g, user_groups ug where g.group_id = ug.group_id and t1.user_id = ug.user_id and g.group_name=’standard’)

NICE

Retrocausality

Author: Cian

I don’t have a lotta time to go into details here, but this is probably the most amazing idea I’ve heard in a long time. From NewScientist, they are trying to send information (via quantum entaglement) into the past using the experiment setup below. The idea is that spacetime is just a big 4D block, and particles send out waves of information without breaking relativity to eachother, by retracing their path over space-time to their counterpart. It also mentions something about antimater / positrons etc, being the same particles but travelling backwards in time instead of forwards. Anyways – if you have troubles interperting what this experiment hopes to accomplish, please let me know.
IMAGE OF EXPERIMENT IN LJ CUT


(edit 11:54am)

Ok now that I have more time to go over this, here’s the skinny. First read Ah-ha! So light doesn’t know where it’s going to go before it goes there! so you understand (loosley used) quantum entaglement. The particular way this experiment works is similar in nature, if we had the same experiment without the KM of fibre, when you moved the movable detector from the position where you detected a wave to the position where you detect a particle, it affects what the other detector detects as well (instantly). John Cramer proposes the “transactional interpretation” of quantum mechanics, stating that basically particles interact by sending and receiving physical waves that travel forwards and backwards through real ‘time’. Or more to the point, no ‘necessarily’ forwards or backwards, but that they freely travel through space-time. The thing about quantum mechanics (in the math anyways) is that time really doesn’t play a big role as far as shaping what can and cannot be done. So quantum ‘entanglement waves’ theoretically should traverse all space-time. Therefore, in this new experiment, when you move the movable detector to a specific position (particle or wave position) the other detector should already be telling you what position you’re going to move it to.

Now this experiment hasn’t been compelted yet, as there is a lot to do to set it up, and to remove noise from the experiment, but it is expected to be completed over the next few months.

http://blogs.pcworld.com/techlog/archives/002950.html

Tweel from Michelin

Author: Cian

http://www.youtube.com/watch?v=fqRJ9GfIJtI
Wow next generation car tyres!