Or maybe they are all at Milliways, which is also known as the Restaurant at the End of the Universe?

Or maybe they are here, and we call them UFO's. Brian didn't consider that. 🤔

If they aren't here, and aren't out there, in our galaxy, then the hypothesis that they are rare, and due to the extreme time scales none of the civilizations overlap, would seem to make sense. 

15 minutes ago, martin-w said:

Or maybe they are here, and we call them UFO's. Brian didn't consider that. 🤔

If they aren't here, and aren't out there, in our galaxy, then the hypothesis that they are rare, and due to the extreme time scales none of the civilizations overlap, would seem to make sense. 

Martin, they are here and probably your neighbors.  Ever notice anything unusual going on? 👽

1 hour ago, charliearon said:

Ever notice anything unusual going on? 👽

 

😲 Come to think of it...

We can never find the aliens now or in the foreseeable future. We have to rely on highly advanced aliens finding us. As we have been broadcasting radio transmissions for maybe 100 years, and as our galaxy is about 100,000 light years in diameter there could be millions of alien civilisations who would have no way of  knowing we exist and would have no reason to look for us.

Since our sun and planet are far out toward the edge of the galaxy why would they come way out here?  Wouldn't their explorations be nearer to the center of galaxy were there are more stars and planets to explore?

Unless they found us by accident and decided to send missionaries and start pineapple plantations.

Noel

5 hours ago, dmwalker said:

We can never find the aliens now or in the foreseeable future. We have to rely on highly advanced aliens finding us. As we have been broadcasting radio transmissions for maybe 100 years, and as our galaxy is about 100,000 light years in diameter there could be millions of alien civilisations who would have no way of  knowing we exist and would have no reason to look for us.

You're assuming that radio transmissions would be the only way to find us.

Also, 3 billion years of life on this planet is a long time for it to go completely unnoticed.

 

DB

45 minutes ago, DaviiB said:

You're assuming that radio transmissions would be the only way to find us.

Also, 3 billion years of life on this planet is a long time for it to go completely unnoticed.

In order to be noticed, we would have to have some noticeable activity which could be detected from many light years away. For almost all of the 3 billion years, there was no intelligent life and nothing to be noticed. 

If they could have spotted our planet in the first place, alien observers might have found our atmosphere interesting but not enough to come and visit. What sign of intelligent activity, other than radio transmissions, might they look for? Are you thinking of some kind of advanced technology they might use?

9 hours ago, charliearon said:

Martin, they are here and probably your neighbors.  Ever notice anything unusual going on? 👽

Never noticed anything odd about my neighbours. Well.. except that they do spell 'neighbours differently to the rest of us round here.🤔

 

Radio transmissions from earth don't get very far before they are completely indistinguishable from the background noise. I don't remember how far it is but on a cosmic scale they might as well be going no further than the edge of the solar system. Even so if you buy into our current scientific understanding the furthest you'll find a signal from earth is about 100LY away which would limit any signal we have generated to 1/10000th the diameter of the Milkway galaxy. So if there was a civilization as advanced as ours on average no more or less than say 200LY apart in our galaxy that would mean that hundreds of thousand of alien civilization as advanced as ours are in the milky way and we wouldn't have a clue they were there and they wouldn't have a clue we were here! But if artificial radio waves can make it that far then some day about 100 years from now the milky way is going to light up like a frigging Christmas Tree!🤔🤪🤣

6 minutes ago, FBW737 said:

But if artificial radio waves can make it that far then some day about 100 years from now the milky way is going to light up like a frigging Christmas Tree!

And it would be another hundred years before we knew about it.

20 hours ago, stans said:

Or maybe they are all at Milliways, which is also known as the Restaurant at the End of the Universe?

Burger King will go bankrupt, and then reopened by tiny head Mexican space aliens. Jumbo Jupiter Sandwiches and Mercury Fries!

14 hours ago, FBW737 said:

I don't remember how far it is but on a cosmic scale they might as well be going no further than the edge of the solar system.

 

Radio waves extend without limit into space, but they are subject to the inverse square law. In terms of being potentially readable, it depends how powerful the transmitter is and how sensitive the receiver. If the signal to noise ratio is above a certain level, its potentially readable. Technology could enable us to communicate with radio waves over extreme distances, you just need as bigger more powerful transmitter. In fact, military radar transmissions during the cold war had the power and frequency to be detected over 100's of lightyears.  The laws of physics don't limit us in terms of distance we can communicate, it's an engineering problem. 

 

23 hours ago, dmwalker said:

there could be millions of alien civilisations who would have no way of  knowing we exist and would have no reason to look for us.

 

According to the Fermi Paradox, if just one civilization in our galaxy survived and didn't destroy itself, it would take, even at the sedate velocities we travel,  less than the age of the Earth to colonize the entire galaxy. And yet we see and hear nothing, no Dyson spheres, no ring worlds, no interstellar highways, no radio transmissions, no commination with other means, like lasers. And if the UFO's we see aren't alien's, no visitors here. Nothing, the galaxy seems quiet.. 

My feeling is that given primitive life appeared on Earth as soon as it cooled its probably common in the galaxy, but given that advanced technological life (us) took one third the age of the universe to evolve on Earth it seems to be very hard and thus vary rare in our galaxy. 

I say our galaxy rather than the universe because out best measurements tell us that the universe appears to be flat, thus probably infinite, and if so, pretty much anything can be manifest in an infinite universe because atoms have a finite number of ways they can arrange themselves. 

Edited October 1, 20232 yr by martin-w