Space time

Riddles of space time
they crop up and multiply
as you solve some
some more remain unresolved

What is dark energy
even dark matter is less understood
if gravity is common denominator
how negative pressure is understood

Matter expands and becomes less dense
then how density of dark energy remains uniform
and if this is the cost to occupy some more space
then energy exists and fills even unoccupied space

Universe expands at an accelerating rate
how pressure is uniform relativity fails to explain
for mass per unit has to change
and density can't remain the same

Something more need to exist
to explain what remains unexplained
dark energy is energy still
its manifestation needs to be explained!