What If We ARE Alone?

[jwoodie]

Here are some thoughts about the STATISTICAL likelihood of life existing outside of Earth. It seems to me that we may be looking through the wrong end of a telescope by presuming that because life exists on Earth, it MUST exist elsewhere in the universe. What if it doesn't?

One way to look at this question is through statistical sampling. Let's hypothesize that there are 10 billion data points in the universe. Let's also take a random sample of a billion of these data points in order to determine the probability of life in the universe. A sample of this size is certainly enough to provide a confidence level of near certainty regarding its results. What if no life was detected in this sample? Wouldn't this lead us to conclude that there is no life in the universe?

Another way to look at this question is through probability calculations. A well-known equation is often used to assign probabilities to a finite number of conditions presumed to be necessary for life to exist and then essentially multiply them by infinity to produce a foregone conclusion of life existing elsewhere. However, since infinity is NOT a number, the universe can not contain an infinite number of data points. As a result, these calculations are based on a type of circular logic.

In addition, all of the conditions necessary for the creation of life are not known. But even if they were, the probability of them simultaneously occurring at the same time and place may be extremely small. Even without the time element, if there were 100,000 of these conditions with each having a one in a 100,000 probability of existing, there would be less than a 50% probability of them all occurring more than once.

Maybe we ARE all alone in the universe.

 

[jwoodie]

P.S. A "random sample" is NOT random if a particular data point (Earth) is deliberately inserted into the sample.

 

[Ralph Norton]

A well-known equation is often used to assign probabilities to a finite number of conditions presumed to be necessary for life to exist and then essentially multiply them by infinity to produce a foregone conclusion of life existing elsewhere. However, since infinity is NOT a number, the universe can not contain an infinite number of data points. As a result, these calculations are based on a type of circular logic.

If you are referring to the Drake Equation - where does "infinity" come into play?

Maybe we ARE all alone in the universe.

It's likely we will never know one way or the other.

 

[jwoodie]

If you are referring to the Drake Equation - where does "infinity" come into play?

It's likely we will never know one way or the other.

The Drake equation is a nice example of probability calculations, but its assumption of positive values for all of its variables and an ever expanding number of stars (~infinity) is not based on empirical data. Why presume that Earth is NOT the only instance of (intelligent) life in our Galaxy? Is there ANY evidence to the contrary?

I think it is highly likely that the (miraculous?) conditions NOW existing on Earth are singular events. The only life we may ever encounter elsewhere may be that which we transport from Earth.

 

[Mushroom]

I think it is highly likely that the (miraculous?) conditions NOW existing on Earth are singular events.

Because all understanding on the formation of the Universe state it is highly unlikely.

The universe is around 13.7 billion years old. However, the earliest stars were all Population III stars. These would have had no planets, as the only elements were hydrogen, then hydrogen and helium as they fused their hydrogen. Then when enough of those started to spit out some of the lighter elements like lithium, boron, oxygen, and carbon they started to create the Population II stars. Those were metal poor, and the earliest ones would still not have had planets, there was simply not enough heavier elements to form any. However, a few generations of those and we started to see the even heavier elements created, like iron, calcium, and the like.

We live around a Population I star, which is very rich in heavier elements thanks to the late Population II or early Population I supernova that gave birth to the cloud out system formed in. But most tend to believe that star systems with the right kind of chemical makeup were not even possible until around 6-7 billion years ago. And while estimates vary, most believe that no more than 10% of stars are Population I stars. St that right off the bat reduces even any possible places that life can form to only 10% of stars.

You can not start with the number of stars, because the vast majority will not have the right kinds of elements to create life at all. That is why so many are excited at the JWST possibly finding proof of Population III stars, in that it can help us nail down the timeline of the earliest star formation and take it from theory to accepted fact.

 

[luiza]

As we are already aware of double digit other races and deal with a couple of them , your hypothesis is debatable .To put it mildly .

Of course such a comment is completly off limit and deemed far -out conspiracy , if not outright garbage by Normies , which is hardly surprising .

I simply hope to be around when the official position finally changes, which will give me considerable intellectual satisfaction .
Until then , I continue to smile .

 

[norwegen]

Billions of planets are in the Milky Way, they say. The first requirement for intelligent life is that a planet lies consistently in a habitable zone (in a circular or nearly circular orbit at a certain distance from its star). That would reduce the billions to what - maybe a billion?

Then myriad other requirements for such life must be met.

The likelihood that intelligent extraterrestrial life exists in this galaxy is infinitesimally small.

And even if intelligent life did exist on another planet, the likelihood that it could pay a visit to our planet is virtually impossible.

 

[zaangalewa]

Here are some thoughts about the STATISTICAL likelihood of life existing outside of Earth. It seems to me that we may be looking through the wrong end of a telescope by presuming that because life exists on Earth, it MUST exist elsewhere in the universe. What if it doesn't?

One way to look at this question is through statistical sampling. Let's hypothesize that there are 10 billion data points in the universe. Let's also take a random sample of a billion of these data points in order to determine the probability of life in the universe. A sample of this size is certainly enough to provide a confidence level of near certainty regarding its results. What if no life was detected in this sample? Wouldn't this lead us to conclude that there is no life in the universe?

Another way to look at this question is through probability calculations. A well-known equation is often used to assign probabilities to a finite number of conditions presumed to be necessary for life to exist and then essentially multiply them by infinity to produce a foregone conclusion of life existing elsewhere. However, since infinity is NOT a number, the universe can not contain an infinite number of data points. As a result, these calculations are based on a type of circular logic.

In addition, all of the conditions necessary for the creation of life are not known. But even if they were, the probability of them simultaneously occurring at the same time and place may be extremely small. Even without the time element, if there were 100,000 of these conditions with each having a one in a 100,000 probability of existing, there would be less than a 50% probability of them all occurring more than once.

Maybe we ARE all alone in the universe.

So no alien road hog who crosses our solar system with 99.999999999999% lightspeed? Wonderful.

 

[AsherN]

Billions of planets are in the Milky Way, they say. The first requirement for intelligent life is that a planet lies consistently in a habitable zone (in a circular or nearly circular orbit at a certain distance from its star). That would reduce the billions to what - maybe a billion?

Then myriad other requirements for such life must be met.

The likelihood that intelligent extraterrestrial life exists in this galaxy is infinitesimally small.

And even if intelligent life did exist on another planet, the likelihood that it could pay a visit to our planet is virtually impossible.

I agree on the orbit. Climate must be reasonably stable to sustain life. But nothing else needs to be like Earth. Life can be non-carbon based. Can exist in lower or higher gravity, etc.
Now, the likelihood of a visit is pretty much nil, as far as we know. It is so based on our understanding of physics. That may not be all there is.

 

[Mushroom]

Climate must be reasonably stable to sustain life.

Oh, this is complete nonsense. The "climate" on our planet has changed from an average global temperature of over 40c (100f), to times where the planet was almost completely covered by ice.

Yet life survived.

If anything, I would argue the exact opposite. That once life is established, it is almost impossible to kill off and will survive in almost any climate and condition thrown at it. Life even today can survive in total darkness, temperatures that are above boiling and below freezing. Even in acids and alkalis that should be fatal, but somehow they manage to survive in. Hell, we even know now that life can even "survive" in the cold and vacuum of space.

 

[para bellum]

...It seems to me that we may be looking through the wrong end of a telescope by presuming that because life exists on Earth, it MUST exist elsewhere in the universe. What if it doesn't?

Then nothing changes...

 

[norwegen]

Oh, this is complete nonsense. The "climate" on our planet has changed from an average global temperature of over 40c (100f), to times where the planet was almost completely covered by ice.

Yet life survived.

If anything, I would argue the exact opposite. That once life is established, it is almost impossible to kill off and will survive in almost any climate and condition thrown at it. Life even today can survive in total darkness, temperatures that are above boiling and below freezing. Even in acids and alkalis that should be fatal, but somehow they manage to survive in. Hell, we even know now that life can even "survive" in the cold and vacuum of space.

Extremophiles can live in heat vents deep in the ocean and on silicate in deep space.

 

[norwegen]

I'm no expert, but I'd hazard the life must be carbon-based. It could only have originated from exploding stars.

 

[Mushroom]

Extremophiles can live in heat vents deep in the ocean and on silicate in deep space.

I find extremophiles to be fascinating, to be honest. And many are now thinking a lot of them are simply the last remnants of life that had existed earlier then remained in isolated spots as the rest of the planet changed around them.

Some of the ones that live in deep caves in hypoxic environments are actually closer to the first live on the planet than what exists on the surface today. But the earlier composition of our atmosphere had almost no oxygen, and was high in gasses like CO2, CO, and high concentrations of sulfides. That changed during the Paleoproterozoic with the Great Oxygenation Event, and those hypoxic extremophiles many now believe are little more than "lifeboats" for some that were underground and did not die on the surface as most had.

And of course in many of those environments, later more advanced lifeforms were able to adapt and live in them also, setting up some unique ecosystems.

And the Tardigrade may ultimately be the longest living species on our planet. As when pretty much all life goes extinct in a few billion years, it is possible they can continue. It would be ironic if in a few dozen billion years, the "earth life" that recolonizes on a future planet is the lowly tardigrade, which could possibly survive the destruction of our planet and star and after floating in the cosmos could possible have enough survive to set up a home elsewhere.

 

[AsherN]

Oh, this is complete nonsense. The "climate" on our planet has changed from an average global temperature of over 40c (100f), to times where the planet was almost completely covered by ice.

Yet life survived.

If anything, I would argue the exact opposite. That once life is established, it is almost impossible to kill off and will survive in almost any climate and condition thrown at it. Life even today can survive in total darkness, temperatures that are above boiling and below freezing. Even in acids and alkalis that should be fatal, but somehow they manage to survive in. Hell, we even know now that life can even "survive" in the cold and vacuum of space.

In the geological time scale, sure. but a planet having to much of an elliptical orbit, bring massive fluctuation with a cycle is not suited to sustain life.

 

[Mushroom]

In the geological time scale, sure. but a planet having to much of an elliptical orbit, bring massive fluctuation with a cycle is not suited to sustain life.

Really?

Funny, it happened here.

 

[AsherN]

Really?

Funny, it happened here.

Our orbit is relatively circular. We're talking about elliptical orbits that would say, bring the planet as close as we are and as far a Mars.

 

[Mushroom]

Our orbit is relatively circular. We're talking about elliptical orbits that would say, bring the planet as close as we are and as far a Mars.

We are relatively circular, now. But that does indeed change, and it becomes very elliptical on roughly 400k year cycles. In fact, the two main cycles of how elliptical our orbit is also tends to fall in nicely with ice ages on our planet. And at this time we happen to be more circular than is average for the planet. But we have gone through multiple such cycles over billions of years, and amazingly life still thrives here.

But come on not, as far as Mars? 150 million miles away? That has never happened and will never happen.

If you are going to make up scenarios, at least make them fit into the laws of science.

 

[braalian]

I don’t get why the idea bugs so many people so much. So what if we *are* alone?

Yeah, I’m curious too, but life is short and we’ll likely never know in our lifetimes.

 

[Calypso Jones]