Why the masses in DPD and eDPD model formulas are defined as 1?

LAMMPS LAMMPS Beginners
1

I have very basic question. In the LAMMPS documentation for eDPD (Description)

https://docs.lammps.org/pair_mesodpd.html

looking at the formulas, mass=1 and it does not appear in the Newtonian fromulas. However writing the input file and defining the beads we are able to have mass as an input.
My question is why the mass is defined as 1 in the formulas? if the masses are defined as one, then what are the masses we define the input file? what is the logic? I am confused.

Thank you so much.

2

This is a very specific question that you should ask the contributor of the pair style in question.
You can usually find a contact info of contributing authors in the source code.
You may also try looking up name and affiliation here: 6.2. Package details — LAMMPS documentation
and then use a web search to figure out further contact details. Sometimes the latter is needed, if people have moved on to a new position/institution since when they contributed their code to LAMMPS.

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