New Gravity is the only proposal that gives an explanation of how gravity works.  It is based on the accepted fact that every substance in existence is 99.99% at least empty.
Only a comparatively tiny amount is energy. This energy forms apparently substantial matter entirely from what has long been considered nothing, empty space. Empty space moves and in doing so creates energy. The movement of space soon turns to spin and this is the beginning of gravity. The screw like effect pulls space to itself. Trillions of similar
sub-microscopic units are produced and as there is no resistance they last forever. Over billions of years  greater and greater masses  form and allow more complicated forms and properties such as magnetism to occur quite naturally. The universe we see today is the same size it always has been. The content has altered over time by gravity.
Gravity pulls on space only, any solid is moved by the streams of space on their way to the masses which are constantly Impelling space towards them. The solids go with this permanent flow . New Gravity works, Big Bang does not.