Can you store a reference to a primitive value?

I have a class that stores a large array (it holds one scalar double value for each vertex of the mesh it's attached to). I want to give the user the option to display the scalar value at a specific vertex on some UI text. But accessing the array of my original script over and over again in the Update function seems wasteful.

I would actually like to just keep a permanent reference to that specific double value in my original array, so I can just do an array access once, and my reference will forever be able to tell me the value there.

     public class Example : MonoBehaviour
     {
         public double[] scalars = new double[mesh.vertices.Length];
         void Awake()
         {
             ...fill scalars...
         }
         void Update()
         {
             ...scalars changes...
         }
     }
     
     public class ExampleInfoDisplay : MonoBehaviour
     {
 >>>>>>> public ref double numReference; <<<<<<<
         public int indexToFollow;
         public Text uiText;
         void Start()
         {
             numReference = gameObject.GetComponent<Example>().scalars[indexToFollow];
         }
         void LateUpdate( )
         {
             uiText.text = numReference.ToString();
         }
     }

This might not seem like that much work, but because of how the rest of my system works, my real script actually has to do a lot of nested array accesses to get the correct value, since I'm using Dictionaries paired with other arrays and so on. The real access in my LateUpdate looks more like:

 public class ExampleInfoDisplay : MonoBehaviour
 {
     ...
     Example example;
     void LateUpdate()
     {
         uiText.text = example.scalars[example.vertDictionary[example.uniqueVerts[indexToFollow]][0]].ToString();
     }
 }

I know that I could just make a wrapper class called Double which stores a double value, and then make scalars an array of Double instead of an array of double. I would like to just be able to store a single reference when I need it, since an array of 64-bit doubles is already quite large, and I would rather not have to store an array of 64-bit references which each have their own 64-bit values.

TLDR: I know that you can pass values by reference to methods using the ref, in, or out keywords, and that knows how to create a one-time reference to that primitive value. But what I need to know is, can you store that reference somehow and reuse it?