https://www.scientificamerican.com/arti ... g-problem/TL;DR, IINM:
Einstein had a placeholder, lambda, as a "cosmological constant" assuming the Universe is static. But there is some kind of energy causing the Universe to expand when one might think gravity should hold it all together. Basically there is a discrepancy between what theoretical physicists predict should be in "anti gravity" energy and what seems to be happening (universe is expanding, and this expansion is actually accelerating in rate).
So there is some kind of energy there in the "nothingness". There is always some amount of "energy".
It makes me think of "Wuji". There is nothingness, and it is expanding toward infinity. Limitless. Also Qi, in the sense of there is always some "energy" in the Universe, even if there seems to be "nothingness". Eventually, some theories say the cycle repeats (collapse -> Big Bang -> expand again). In which case the Universe is not 13.8 billion years old. Wuji begets Taiji. Eventually, it just repeats. A circle is a good diagram.