wilson-eft / wilson

A Python package for the running and matching of Wilson coefficients above and below the electroweak scale
https://wilson-eft.github.io
MIT License
26 stars 18 forks source link

Implement the LEFT beta functions and their solutions #93

Closed jackypheno closed 1 month ago

jackypheno commented 2 years ago

Implements solutions to LEFT RGEs using LEFT beta functions.

@jasonaebischerGIT @peterstangl at this stage you might upload the extracted beta functions.

@dvandyk this is just a draft, work in progress!

jackypheno commented 2 years ago

I think checks have failed because it needs the file betaleft.py (to be uploaded by @peterstangl @jasonaebischerGIT ).

dvandyk commented 2 years ago

I'm sorry, but I'm confused and seconding @DavidMStraub's comment from wcxf/wcxf-bases#8: What is the difference to what has been previously done in wilson? The current code uses the SMEFT <-> WET matching in the JMS basis. WET and LEFT are interchangeable names for the same effective field theory. LEFT implies using the JMS basis.

@jackypheno So what do you want to achieve with this PR?

DavidMStraub commented 2 years ago

It's about reimplementing RGEs based on San Diego rather than Bern, right?

In any case, WET should not be renamed to LEFT in the public facing API (WCxf etc.) as that would break things. For internal modules/methods it's fine.

jackypheno commented 2 years ago

@dvandyk The main goal of this PR would be:

Solve the WET/LEFT RGEs directly using the beta functions (for example #94) independently from the existing WET RGEs based on the ADMs. This independent solution to the WET RGEs hopefully will allow us to fix #54 .

The name LEFT is used for the Low energy effective field theory only for the internal modules unlike the initial idea of #8. In the current PR the key wet_method introduced that can take two values adms (default, i.e solve using existing implementation) or 'betafunctions' solve using #94. Thats why #8 has been abandoned.

Apart from this: there is plan to generalise the SMEFT class to an EFT class having SMEFT, LEFT, .. as child classes. For the moment there is not much in the EFT class, eventually all common methods of SMEFT, LEFT , .. will move to parent EFT class. This is currently work in progress!

jackypheno commented 2 years ago

@DavidMStraub Yes, I abandoned the stupid idea of adding new name for LEFT. In contrast the flag wet_method would allow the user to choose between the current or the new method of solving the RGEs. It would also allow us to add unittests comparing the two!

It would also be nice the fix #54 in the current implementation so that both methods can coexist.