Doing a double loop in a job in ecs with Job Entites.forech

I am trying to do a double forech loop in Unity ECS within a JOB, a gravitaional like system. I have done it already succesfully with Unity 2018 with a IJOBParalleForEach, but the code didnt work
with Unity 2019 so I tried it now with the new Job Entites.forech and it doesnt work either, I really have no idea why I get the error:
error DC0001: Entities.ForEach Lambda expression uses field ‘physicsMasses’. Either assign the field to a local outside of the lambda expression and use that instead, or use .WithoutBurst() and .Run().

using System.Collections; using System.Collections.Generic; using UnityEngine; using Unity.Entities; using Unity.Jobs; using Unity.Transforms; using Unity.Mathematics; using Unity.Physics; using Unity.Collections; 
public class SwarmSystem : JobComponentSystem {
        public float time;
        public float gravK = 6.674f;
        EntityManager entityManager;
        [DeallocateOnJobCompletion]  NativeArray<Translation> translations;
        [DeallocateOnJobCompletion]  NativeArray<PhysicsMass> physicsMasses;
        protected override void OnCreate()
            var v = GameObject.FindObjectOfType<MyGameManager>();
            entityManager = v.entityManager;
        protected override JobHandle OnUpdate(JobHandle inputDeps)

            EntityQuery q = GetEntityQuery(ComponentType.ReadOnly<IsPartOfSwarmTag>(), ComponentType.ReadOnly<Translation>(), ComponentType.ReadOnly<PhysicsMass>());
            time = Time.DeltaTime;
            translations = q.ToComponentDataArray<Translation>(Allocator.TempJob);
            physicsMasses = q.ToComponentDataArray<PhysicsMass>(Allocator.TempJob);
            var job = Entities.WithAll<IsPartOfSwarmTag>().ForEach((Entity e, ref ForceData f, in PhysicsMass pm, in Translation t ) => {
                for(int i = 0; i< translations.Length; i++)
                    float k = physicsMasses_.InverseMass * pm.InverseMass * gravK;_

float3 vec = t.Value - translations*.Value;*
float length = math.length(vec);
float potenz = math.pow(length, 3);
f.Value += (k / potenz) * vec;

return job;
} }
ForceData is just a float3 IComponentData

It wants you to change it to a local variable

var physicsMasses = q.ToComponentDataArray<PhysicsMass>(Allocator.TempJob);

or make an local alias variable and use it in your job

var localPhysicsMasses = physicsMasses;//use localPhysicsMasses from now on

NOTE: if you make your system inherit from SystemBase you will be able to use Job semantics (imo more fitting here)