Are we alone in the universe?

Post Reply New Topic

Realize that the universe is filled with the same chemistry everywhere and how can you not possibly realize there's life elsewhere.

That is an assumption we make prior to interpreting all of the things we sense remotely.

We have little choice in the matter. If we do not assume the laws of physics are uniform we cannot do physics at all.

To verify the principle of uniformity we would have to observe everything in the cosmos close up and that is a practical impossibility. We have no a priori assurance that the laws of physics will be the same tomorrow as they are today. We have no a priori assurance that the laws of physics are the same ten l.y. away as they are closer in.

ruveyn

No kidding!
Next you're going to inform us that water is wet!

Thanks for telling us what we all already know.
What we dont know is whether or not you have a point.

Unless extraterrestrials are ever found, the only thing for certain is the idle speculation and myriad articles in space magazines with overly sensational headlines every time there's the possibility of liquid water anywhere, assuming that a single item necessary for known life is also sufficient for life to spontaneously generate on its own.

Earth is a deceptively comfortable place - to us. We did evolve here, after all. To the primitive life-forms thriving in undersea vents on this very planet, however, the surface world is a frozen, dry hell, obviously incompatible with life...

There are those who believe the principle of uniformity is axiomatic.

Not everyone is an empiricist.

ruveyn

Gliese 581 has twice Earth gravity. While it may have water, the S.G. would be 2, two-thirds way to rock here, and hope it does not rain. Higher gravity could form rock different from here. A thicker atmosphere can carry more on the wind, and it would be abrasive.

A day at the beach would not take long to reduce us to a pulp.

Under lighter gravity. thin to no atmosphere, you get Mars, and lower down the Moon, where the landing sent up a cloud of dust that just hung above the surface for months, The white out cloud obsured the entire mission. The film version had to be reshot in Texas.

Intelligent life would avoid us. Their first concern would be preserving and improving their habitat. We pillage and befoul this planet like we were ready to move on to the next one.

Our adaptive range is we can live less than three miles above sea level. A little less gravity and that would become a hundred foot. A little more and storms would scour the surface to bedrock.

While there could be life everywhere, it would have little in common. Take birds, Less gravity, the air becomes too thin for flying, and slightly more gravity, the birds too heavy for flight.

Then there is change, A few percent different gravity, either way, and humans might not survive. We have millions of years invested in a very narrow range.

The alien grays, and their short blue helpers could result from just a few percent differance in gravity, they could be the same species, They left Earth, Hundreds to thousands of years in the future, and now time travel to a past that no longer suits them.

Humans have modified head shape, Tying a board to a babies head, Made long neck girls with brass rings, and the Sumarians and others raised babies in clay pots for some extreams of body shape.

Gravity never sleeps, 5% more, babies would become Blues. 5% less, Grays. Travel for generations between the stars, blobs like the Guild Navigators.

Dogs and dolphins tell their human jokes in a range above our hearing.

We are as good as alone with our limited survival range and perceptions.

That we are. Learn to live with it.

ruveyn

So...you dont have any point.

Yes I do. We are unable to -deduce- the cosmos a priori. We have to find out about it the hard way; by looking and measuring. All of our sound knowledge is gained empirically, not by logical deduction.

ruveyn

I second that, and say that looking and measuring on Earth only gives the local view. Time and Gravity are forces we have been unable to alter, Newton made some good gusses about Gravity, I think we will find Time is not a Universal Constant,

While the same materials may be present, how they join can vary. We rule out Gas Giants, for life as we know it, but life does not care what we think. Life around deep sea vents would agree, Too close they get cooked, too far they freeze, but within their range, they debate should taxes be raised, or services cut.

We are very much a product of our background. Neural density, electron flow, the thought process, language, dolphins and whales speak for miles, through water, 900 times denser than air. Higher gravity, everything would have a denser structure.

We know life exists at pressures that would kill us, coming to the surface would kill them. Radio works because we have a magnetic field, because of the structure of our atmosphere. A little change in Physics, it is not a universal medium. SETI looks for Earth like radio waves.

We are looking for ourselves of the last 75 years. That is a narrow slice of potential life. Better we should scan planets seeking a seasonal Methane cycle, such as the great herds produced over the last few hundred thousand years.

It is a good thing we are not going. Humans would eat the locals and strip mine the place. 500 years after the discovery of the New World, it is a toxic wasteland.

As a species, they deserve their place in the fossil record.

We already know that from Einstein's Special Theory of Relativity.

ruveyn

Einstein was an Earther, I am waiting for a second opinion, from Alpha Centaui. Maybe Pluto.

Columbus was part right, and died thinking he had found India. No elephants Cris, dead give away.

Betting that science has it part right has been a winner so far.

Math is the only holdout, that stuff is unbreakable.

If you accept the correctness of the principle of uniformity, physical laws are the same everywhere and every-when since light shone forth from the Big Bang. It is un-necessary to get confirmation from Alpha Centuri and there is no one on Pluto to give a first opinion, let alone a second opinion. We have verified relativity by using dozens of distinct experimental strategies. The results are always the same. Einstein theories hold in a system with a moderate gravitational field like we have in the solar system. It is not clear how well his theories will do in the center of a black hole and we could not find out anyway.

ruveyn

I agree about the moderate gravatational field, the universe must be uniforn to have held together so long. I avoid black holes, the concepts are too much for my mind.

My questions have more to do with the gravational null points between the stars, and time. My view is light moves at the same speed, but the clock stopped. Time not being a constant, and I if I could get there, all physics is personal to me, would I stop with the clock, or continue at my usual pace, forever, an immortal, and how would I know when to eat lunch.

Also how biological systems would work in other gravity. I for one would not last at 2G. The first breeze would knock me down, my own weight would do the rest. What path would life take?

I also do not think much of zero G. Long term it is a one way trip. Being born there most of your bones would disolve.

I do not think humans are going to break out, Earth gravity is our prison.

1. Black Holes are as real as rain
2. Gravitation is the curvature of spacetime. Since we are not getting out of spacetime were are not going to escape gravitation.
3. Humans have already "escaped" earth. Think of how humans put foot prints on the moon.

ruveyn