# correlator

This code computes tree- and one-loop correlators in the U(2) scalar sector of N=4 supersymmetric Yang-Mills. It is written in python and is designed to be run from a GNU/Linux command line. It should be easy to port it to Mac OS X and other operating systems.

First download the correlator code to a file
called `correlator.py`

.

A Multitrace operator such as `tr(X)tr(XY)`

is written as `X,XY`

where
trace are separated by commas. Antisymmetrised `[X,Y]`

is also
incorporated, where numbers label the antisymmetrised pairs, so that
`12,1,2`

stands for ```
tr(XX)tr(Y)tr(Y) - 2tr(XY)tr(X)tr(Y) +
tr(YY)tr(X)tr(X)
```

. In other words `11`

labels one `[X,Y]`

, `22`

another `[X,Y]`

.

To get the tree-level correlator of `tr(XX)tr(Y)tr(Z)`

and `tr(XXYZ)`

(this works for any fields) use the `-0`

switch

```
python correlator.py -0 XX,Y,Z XXYZ
```

To get the one-loop correlator of `tr(XY)tr(XY)`

and `tr(XYXY)`

(this
only works for operators built from `X`

and `Y`

) use the `-1`

switch

```
python correlator.py -1 XY,XY XYXY
```

To find the dilatation operator of `tr([X,Y][X,Y])`

(this only works
for operators built from `X`

and `Y`

) use the `-d`

switch

```
python correlator.py -d 1122
```