Parallel dimensions
There are parallel universes, each expanding indefinitely and they can all host lifePixabay

Are we alone? Humans have been looking for an answer since forever. A group of scientists now believes that aliens do exist, but they are in a parallel universe or in another dimension. And, dark energy might be the common thread between these universes.

Two closely related research papers were published recently by scientists from Durham University. The papers questioned dark energy and the potential for the existence of alien life in other universes, reports ScienceExaminer. Prevailing theories say that there is a certain amount of dark energy in the universe and that amount is ideal for the existence of life. There is just about enough dark energy to allow the formation of planets and suns as well as planets like Earth where life is possible.

Dark energy is also believed to be in the exact right amount to counteract gravity to keep the expansion of the universe accelerating.

These are the theories that the new papers seem to contradict.

Researchers from Durham have concluded in their study that this universe with planets and life would have still happened even if there was 100 times more dark energy present. This is where the existence of alien life in other universes is also raised.

The team ran computer simulations of universes that have different levels of dark energy and found that such universes, if they exist, could also harbour life. What they do understand now is that the existence of life is not entirely based on the availability of dark energy.  As to why there is so little dark energy in this universe, scientists still do not seem to have an answer, but they believe that the multiverse theory does not give the right answers.

Multiverse theory states that seconds after the Big Bang, there was another burst that left the universe expanding indefinitely, but there are some pockets that expand faster than others. This universe is believed to be inside one such pocket that is expanding, but has also stabilized enough to allow stars and galaxies to form. This theory was also countered by Stephen Hawking's last paper, which argued that there can only be a finite number of universes and that there can only be universes that have and follow the same physics as the one we are in now.

If there are, indeed multiple universes and if there are universes expanding parallel to this one, it is a possibility that two universes could bleed into each other. If there is life out there, humans are likely to find it in the future.

The papers were first published in the journal Monthly Notices of the Royal Astronomical Society.