Is the universe filled with intelligent life? Possibly not.

Started by René, September 07, 2019, 09:07:27 am

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Tangled-Universe

PBS Space Time is a great channel which answers many many questions and ideas discussed here:

https://www.youtube.com/channel/UC7_gcs09iThXybpVgjHZ_7g

René

Quote from: Matt on September 10, 2019, 02:40:38 pmYou can't push past c, so there is no possibility of reversing time. To travel at the speed of c in an external reference frame, you travel at infinite speed in the moving frame. No matter how much faster you try to go beyond infinity, you are still travelling at the speed of infinity. To the external viewer this appear to be c. So it's impossible to go faster than this.
Makes sense. No matter how much you add to infinity, it remains infinite.

René

Quote from: Tangled-Universe on September 11, 2019, 06:40:52 amPBS Space Time is a great channel which answers many many questions and ideas discussed here:

https://www.youtube.com/channel/UC7_gcs09iThXybpVgjHZ_7g
Thank you for this. Images and animations help me enormously in understanding abstract matters.

René

The discussion about the existence or non-existence of extraterrestrial life will remain hypothetical until we discover it. In his book Extraterrestrial Civilizations, Isaac Asimov(author) provides the (theoretical) proof that there are many intelligent aliens in the universe. He does this by comparing two magnitudes, namely the number of estimated planets in the universe, and the long series of coincidences that have led to the birth of our planet and the life on it.
It is remarkable that Simon Conway Morris(evolutionary biologist) uses the same evidence and reasoning in his book Life's Solution to show that there may be life outside the earth, but that this probably has not evolved beyond than microbes.

Tangled-Universe

Another complication is the expansion rate of the universe, which is the same for every position within the universe.
At the moment the expansion rate is estimated at about 73km/s/Mpc, where Mpc stands for megaparsec, a unit of distance. (There's heavy debate on this value though, some say it should be lower, like 68)
So the further away an object is, the faster it's receding from us.
Consequently, any object or point in the universe beyond the Hubble radius, approx 14.7B lightyears, has recession speeds faster than the speed of light.

These parts of outside of our observable universe are inaccessible to us, physically but also sensory.
We have no clear idea how large the universe is, we only know limits of our observable universe (constrained to the Hubble radius), but if there's intelligent life out there then some or perhaps all of it may be impossible to reach for us or impossible for them to reach us.

N-drju

Quote from: Tangled-Universe on September 12, 2019, 08:12:09 amWe have no clear idea how large the universe is, we only know limits of our observable universe (constrained to the Hubble radius), but if there's intelligent life out there then some or perhaps all of it may be impossible to reach for us or impossible for them to reach us.

Unless wormholes are proved to exist. Until lately mankind had no idea that bosons exist. Who knows what else could be discovered?

The problem with wormholes might as well lie in the fact that they may be too small or too short-lived for us to even notice and make us of. But it doesn't change the fact that they have a potential to be space tunnels...
"This year - a factory of semiconductors. Next year - a factory of whole conductors!"