Loop QGrav, Quantum field ...

[siddharthsma]

Hi. I'm a beginner to all this stuff. So could someone please help me, and tell me what is a field theory, and what is the Quantum field theory all about ? How is it different from Quantum mechanics or Quantum electrodynamics ?
Also what is Loop Quantum Gravity, what does it involve, what is it about ?
What is Super Gravity ?

Anybody know any books I could read on this stuff ?

[Graybeard]

I am not really sure what you are asking ...... but for a basis on understanding QM ..........................................

http://higgo.com/quantum/laymans.htm .... try this

but you really will need to investigate and conceive to your own understanding, the three experiments this article mentions .....

Two Slits

The simplest experiment to demonstrate quantum weirdness involves shining a light through two parallel slits and looking at the screen. It can be shown that a single photon (particle of light) can interfere with itself, as if it travelled through both slits at once.

Light Bulb

Imagine a light bulb filament gives out a photon, seemingly in a random direction. Erwin Schroedinger came up with a nine-letter-long equation that correctly predicts the chances of finding that photon at any given point. He envisaged a kind of wave, like a ripple from a pebble dropped into a pond, spreading out from the filament. Once you look at the photon, this 'wavefunction' collapses into the single point at which the photon really is.

Schroedinger's Cat

In this experiment, we take your pet cat and put it in a box with a bottle of cyanide. We rig it up so that a detector looks at an isolated electron and determines whether it is 'spin up' or 'spin down' (it can have either characteristic, seemingly at random). If it is 'spin up', then the bottle is opened and the cat gets it. Ten minutes later we open the box and see if the cat is alive or dead. The question is: what state is the cat in between the detector being activated and you opening the box. Nobody has actually done this experiment (to my knowledge) but it does show up a paradox that arises in certain interpretations.

My favourite is the double slit experiment ... which leads ... eventually.. to understanding the implications of Bell's Theorem


Good Luck ...

Greg