This paper suggests that entropy, one of the basics of thermodynamics, virtually dictates that if sufficiently high energy sources are available, carbon compounds are very likely to develop into organic compounds, and particularly the kind that constitute this thing we understand as Life.
This caps a private discussion that has been taking place, following a news article that includes an interview with an Israeli general. He claimed that some governments have been sharing information about alien (ie off world) beings visiting Earth, but deliberately keeping this secret, as they believe that ordinary people are (for unspecified reasons) unable to cope with the notion of life not on Earth.
The discussion therefore moved on to the factors governing both alien life and the ability for such beings to travel through intergalactic space.
“Do Aliens exist? - I certainly think they do - might not necessarily be LGM.
Have we found them ? - Maybe if you count the recent discovery on Phosphine on Venus.
Have they found us ? - Not yet, I think.”
“Most likely life on earth itself is alien.”
"It is not unreasonable to think that the origin of life on earth had extraterrestrial roots.
While it might seem improbable for living forms to navigate through high speed entry in a heated atmosphere, a number of chance strokes of lightning hitting just the right chemical soups to synthesise the right organic compounds also don’t seem tremendously likely.
Yet, here we are.
Still, with upwards of 14 billion orbits of our solar system as timepass, and uncountable star systems in which Goldilocks conditions might occur, what is probability, anyway?"
“But the experiments conducted in the lab suggest that it is very likely to produce organic compounds including amino acids and nucleotides through simulated lightening (sparks) in a glass chamber.”
The MIT paper cited at the beginning of this post suggests that, in fact, entropy dictates that such reactions are highly likely.
What remains, therefore, to be ascertained is whether the natural barriers of spacetime as determined in Einstein’s equations have some workaround, enabling living beings to travel from planets that resemble ours in terms of supporting similar kinds of lifeforms, and to appear before humans in a manner that we are capable of recognising as living beings.
Such planets will necessarily be in star systems that are many lightyears distant from ours, and therefore completely impractical to travel across using the basic laws of physics.