Is love subjective?

[quinntar]

The most spammed verse of the Bible is John 3:16

 

16For God so loved the world that he gave his one and only Son, that whoever believes in him shall not perish but have eternal life.

 

For the Christian this concept is likely paramount, what else could be greater than love? But love for each one of us is an undefined concept. Some say it's a feeling, some say it's an action, some say it's an ideal, some say it's charity. 

 

I'm pointing out here that the idea of love is not as objective as it seems, there's no unified consensus, no tangible evidence that love is a universal constant. If we take the average Christian at their word we'd have to accept that God loves us and that love is no different than E=mc2. 

 

But why can't we detect the love particle? If God is love and made everything by his love then why haven't we discovered the fundamental law of love? 

 

Say we did discover that love is the glue that stick's this universe together, how would it behave, what are is cause and effects?

(I'll let the Christian fill in the blank's)