Focus Fusion Google TechTalk Take Away Points

Research Links

Original notes from 2008 below.

You can watch the focus fusion Google TechTalk here – ( the link died but I leave the text for old times sake.  It was on our long dead friend Google Video ) 

  • We need cheaper energy not more expensive alternatives.
  • In order to merely provide the rest of the world with european level power will require 4X current energy investment.  We won't get there from here.  That includes fossil, nuclear, solar and wind power.  All together insufficient.

 

 Currently popular alternatives are not energy dense enough to get the price of energy down.  Material costs are too much.  Added benefit?  If we can make it work it will lead to propulsion that will allow sending probes to the nearest stars.

…….It's been a long time – Still nuttin as far as I can tell. 

What is Entropy?

There are many mathematical definitions of entropy.  The mental picture I find most useful is to imagine the following:  

  • you are put in a room and your job is to label everything in the room with a sharpy indelible marker and masking tape.  
  • You are asked to label everything in the room using the binary numbering system.  This binary number will be that particular objects I.D.

As you go about this you may want to number the objects you most commonly refer to with the lower digits that have less length.  That way since you mention "FORK" much more often than "NUMBER 6 SCREW" you will end up having to say less digits.

The measure of entropy in this room is the number of binary digits required to number all the objects.  This is entropy.  The formula for this sentence that I just said is:

             Entropy ~= log2N    where N is the number of different types of objects in the room

Now in a probabalistic situation with outcomes  x1 , x2 ….  xn    with P(xi) = probability of xi

…..more

Hey you – Get out of there!

A friend of mine had a very loud voice.  As we were driving he would spot someone keying the lock on their own car or house.  He would shout in the loudest voice possible:  "HEY YOU …. GET OUT OF THERE".   The funniest part is that it worked.  People would jump and look guilty as if they were breaking into their own homes!

It is a bathroom

A couple of friends of mine used to do a funny prank wherein they would wait until someone was walking into some area they were unfamiliar with.  The would blurt out a curt "It's a bathroom" … and the more times than not the person being pranked would dead foot stop and turn around.

Edward Farhi talk on Adiabatic Quantum Computing

Good presentation on adiabatic quantum computation.    In information theory class I learned that by using the Laplacian form and maximizing entropy you can find the description of physical systems.  The adiabatic minimization will work well in these scenario.

Research Links

Quantum Mechanics Entanglement and Spooky Action at a distance

Very interesting and experimental approach to entanglement and Bells inequality.
    

Interesting points of note in the video

  • pop bottle bottom glasses on 70's guy!
  • Eigenvalues of a quantum mechanical solution are what you can observe.  You never observe solutions that are combinations of eigenvalues.
  • StarTrek looking test apparatus mock up.  Scotty would have felt at home fixing this bugger!
  • Einstein did not like ghostly action at a distance.  EPR
  • Assume quantum theory is incomplete: Look for a hidden variable. Photon pairs are emitted with a shared equal hidden parameter.
  • Theories using hidden variables have been created that preserve locality and realism
  • Experiments that only test perfect correlations do not force us to choose between quantum explanation and hidden variable method
  • John Bell was the first person to show how to bring the two theories into conflict so they could be tested
  • Testing perfect correlations are tantamount to looking at one sock and seeing it is blue and concluding the sock on the other foot is blue
  • Imperfect correlations: set the target polarizers at unequal angles.
  • Alain Aspect and company tested Bell's Theorem
  • Tunable lasers were required for this test setup

More …….