Here we know that our most imaginative theory "String Theory" tell us that Gravity is just Graviton, flying across space and time. (I don't actually believe in that)

For Energy. Yeah! It is the best question. I don't know. Energy starts from nowhere and goes to nowhere. xD
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"Every moment of your life is infinitely creative and the Universe is endlessly bountiful. Just put forth a clear enough request, and everything your heart desires must come to you."
written by Shakti Gawain