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Can somebody tell me what is wrong/right with my theory


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So I made this diagram to explain my ridiculous thinking which is probably wrong on many levels.  I am aware they are looking for planets within stars that have suitable or imitatable conditions to our planet to support the notion that "life could exist on other worlds" .... I wonder, (and this may already be the case) ... are they factoring the evolutionary development time , in particular from single cell to multicellular organisms and the other regions in the universe that will also share a similar time point as sol/ our galaxy is from the centre of the universe.  I just wonder if it is a thing where they explore within a specific range because of a justified thinking that other life will also evolve in a specific region of the universe... where is my thinking incorrect ? much appreciate any input on this... apologies for my stupid picture.

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Firstly, the Universe does not have a diameter. It also does not have a centre.  I really am not even sure where to start with your "theory".

The big bang happened everywhere at once. I will not be responding to this thread any more. Bye. If I could block you I would!

that's not very nice , especially considering i rebuked your previous comment ... i didn't say i knew it all  ,so we are in the same camp friend

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20 minutes ago, ShinyTwelve said:

The big bang happened everywhere at once. I will not be responding to this thread any more. Bye. If I could block you I would!

also this point is irrelevant as over time "everywhere" became just a small point as the universe expanded .... seriously i dont know much at all , basic stuff man ??

 

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Let's first start that universe has a center - and it's pretty much every point in universe (for this reason one might argue that there is no center - as center can be only one?)

Universe also has an edge - and this edge is different for every center. There are actually many horizons - which can be thought as of edges of the universe.

Back to original notion of searching for life - that is something that we can both do and is sensible to be done - only in immediate vicinity.

This means stars systems that are our very neighborhood in our own galaxy.

Size of observable universe is 13.8 Bly (not sure if it helps here to think in comoving coordinates as causality does not travel faster than light), while size of our galaxy is about 100,000 Ly in diameter. That is 5 orders of magnitude difference in size.

In our own galaxy there is like a quarter of a trillion of stars. So yes, we search in our immediate vicinity, simply because:

- our sensor can only work with these distances

- any signal sent by alien race falls of in intensity with square root of distance

- if for example we would want to exchange a few ideas with them - it would take about 10000 years to do so for near by planets (500-1000ly distance and then 5-10 round trips in questions and answers :D ).

Btw - your diagram above is wrong in more aspects - like I already mentioned - there is no preferred center of the universe and it's best if you start with earth being the center as consequently "edge" will be well defined with respect to us.

You are mixing comoving distance to edge of observable universe with "time of flight" distance to the edge of universe - one being ~46 Bly radius while other being ~13.8 Bly.

Time flows in each point in universe so every point in the universe is "now" 13.8 By old (note that word "now" is in parenthesis as there is no simultaneity in relativity) - goldilocks zone according to your assumption is now everywhere in universe.

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Greggy-spaceboy to answer your question directly  "do exoplanet hunters factor in their searches a filter of an evolutionary timeline" then I suspect the answer is no.  I may be wrong but I think they simply look for the signature affects of an orbiting planet on its parent star (radial velocity and light curve dip) . Once they detect a candidate star it is then a matter of looking at size of the planet and its distance to the star to consider whether it resides in the habitable zone.  To be honest I've not really considered the necessity for an time bar threshold for life. By my way of thinking , if life is a natural and inevitable consequence of the characteristics of our universe then surely the only precursor is the conditions - stars and the chemistry.  I suppose then the only time bar would then preclude life emerging in the timeline of first generation stars - organic building blocks not yet created and scattered across space !  Im not really sure about that last part but that is my thinking anyway.  

 

Jim 

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Not sure I follow. I think the main plan is to hunt for extrasolar planets wherever they can find them. It's going to be easier to spot them near us.

I also don't think you can extrapolate how long it takes life to evolve from a single sample (us). 

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2 minutes ago, vlaiv said:

Let's first start that universe has a center - and it's pretty much every point in universe (for this reason one might argue that there is no center - as center can be only one?)

Universe also has an edge - and this edge is different for every center. There are actually many horizons - which can be thought as of edges of the universe.

Back to original notion of searching for life - that is something that we can both do and is sensible to be done - only in immediate vicinity.

This means stars systems that are our very neighborhood in our own galaxy.

Size of observable universe is 13.8 Bly (not sure if it helps here to think in comoving coordinates as causality does not travel faster than light), while size of our galaxy is about 100,000 Ly in diameter. That is 5 orders of magnitude difference in size.

In our own galaxy there is like a quarter of a trillion of stars. So yes, we search in our immediate vicinity, simply because:

- our sensor can only work with these distances

- any signal sent by alien race falls of in intensity with square root of distance

- if for example we would want to exchange a few ideas with them - it would take about 10000 years to do so for near by planets (500-1000ly distance and then 5-10 round trips in questions and answers :D ).

Btw - your diagram above is wrong in more aspects - like I already mentioned - there is no preferred center of the universe and it's best if you start with earth being the center as consequently "edge" will be well defined with respect to us.

You are mixing comoving distance to edge of observable universe with "time of flight" distance to the edge of universe - one being ~46 Bly radius while other being ~13.8 Bly.

Time flows in each point in universe so every point in the universe is "now" 13.8 By old (note that word "now" is in parenthesis as there is no simultaneity in relativity) - goldilocks zone according to your assumption is now everywhere in universe.

Wow ok that was a awesome answer thank you so much for putting the time into responding !!! I get most of what you are saying the most important part perhaps being the ability of our sensors not able to reach outside of our galaxy , thank you sir.

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5 minutes ago, saac said:

Greggy-spaceboy to answer your question directly  "do exoplanet hunters factor in their searches a filter of an evolutionary timeline" then I suspect the answer is no.  I may be wrong but I think they simply look for the signature affects of an orbiting planet on its parent star (radial velocity and light curve dip) . Once they detect a candidate star it is then a matter of looking at size of the planet and it's distance to the star to consider whether it resides in the habitable zone.  To be honest I've not really considered the necessity for an time bar threshold for life. By my way of thinking , if life is a natural and inevitable consequence of the characteristics of our universe then surely the only precursor is the conditions - stars and the chemistry.  I suppose then the only time bar would then preclude life emerging in the timeline of first generation stars - organic building blocks not yet created and scattered across space !  Im not really sure about that last part but that is my thinking anyway.  

 

Jim 

I think this is also a pretty valid and awesome point ... the way i was looking at it was that earth had "certain conditions" that were assumed to be available in other parts of the universe so i just looked at time and probabliity of single cell evolution

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For what it's worth I think the question was an interesting one , and I don't know why but I'd never really considered it before !   Ask the same question of a sterile Earth with all the necessary precursors - would there be a necessary time line threshold before life could arise.  Surely not, surely if it is a random and inevitable occurrence it is just  probability and luck of the right molecules being present in the right conditions.  Or am I missing something fundamental?

Jim 

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7 minutes ago, rnobleeddy said:

Not sure I follow. I think the main plan is to hunt for extrasolar planets wherever they can find them. It's going to be easier to spot them near us.

I also don't think you can extrapolate how long it takes life to evolve from a single sample (us). 

My understanding of the limitations of sensors was notable ... i was trying to look at it from a time/evolutionary point of view exclusively .. i appreciate there would be many holes thanks for the response.

 

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1 minute ago, saac said:

For what it's worth I think the question was an interesting one , and I don't know why but I'd never really considered it before !   Ask the same question of a sterile Earth with all the necessary precursors - would there be a necessary time line threshold before life could arise.  Surely not, surely if it is a random and inevitable occurrence it is just  probability and luck of the right molecules being present in the right conditions.  Or am I missing something fundamental?

Jim 

i believe single cell organisms evolved into multi-cell they believe due to a predator ... that predator would perhaps not of existed on the planet before but perhaps came from external meteorites that crashed on the earth, started to gobble the single cells , which provoked them to evolve.  Once that happened complex life happened really quickly , (500million years to get to us) .. i felt it is an important point perhaps if somehow we could look at earth's relative positiion in the universe and look at areas that are "a similar age"

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To deal with your model first, the universe does not necessarily have a radius of 45.6 billion light years.  The article you link to says it's the estimated current distance from us of the furthest galaxies we can observe (the light from which has taken 13.8 billion years to reach us).  It says nothing about the actual size of the universe.  It may be infinite.  Or perhaps it isn't.

Secondly, there is no specific "place" where the Big Bang happened.  It happened everywhere at once, and until it happened there wasn't really much of anywhere at all.  If you like, the Big Bang "created" space.  As the universe expands (as far as we know), everything is not moving away from some "centre", but moving away from everything else (there are exceptions to this).  The universe is not expanding to fill some pre-existing space.  This is not a particularly easy idea to get one's head around and isn't anywhere near as simple as the few sentences I've just used to describe it.

So, yes, I'm afraid your model is, as you say, "wrong on many levels".  There are some good books that try to explain it to people who don't do cosmology for a living though.  I quite like Simon Singh's "Big Bang", perhaps partly because he was a couple of years above me at school :)  I believe Marcus Chown covers it in several books, too (and far more besides).

As regards the search for life, I don't think scientists currently care about evolutionary development time.  My understanding is that life is considered to have started very soon after the Earth cooled sufficiently.  That might suggest we got lucky, or it might suggest that life of some sort will start pretty much as soon as conditions allow.  Right now it would be a major leap forward to find any kind of life at all, so anything that looks like a planet capable of maintaining water in a liquid state, as was the case when life is believed to have started on Earth, is probably considered "of interest".

If you're after live that's multi-celled or has technological society then you might need to factor in evolutionary time, but whilst it would be fascinating I really don't think that's the primary goal right now.

James

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1 minute ago, Greggy-spaceboy said:

i believe single cell organisms evolved into multi-cell they believe due to a predator ... that predator would perhaps not of existed on the planet before but perhaps came from external meteorites that crashed on the earth, started to gobble the single cells , which provoked them to evolve.  Once that happened complex life happened really quickly , (500million years to get to us) .. i felt it is an important point perhaps if somehow we could look at earth's relative positiion in the universe and look at areas that are "a similar age"

I haven't came across the "external predator" theory before but I guess that evolutionary pressures are inevitable as they would arise from any "stress point" . A stress point being a condition which places a challenge to the organism, environmental change being the most likely.  Stress in turn would give rise to natural selection processes which would favour organisms with advantageous mutations.  So I'm guessing, again I'm not on solid ground here,  that evolution could occur without an externally arrived predator to light the blue touch paper.  Homegrown (evolved) predators would of course in turn eventually bring additional stress points and perhaps accelerate the natural selection process. 

 

Jim

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2 minutes ago, saac said:

I haven't came across the "external predator" theory before but I guess that evolutionary pressures are inevitable as they would arise from any "stress point" . A stress point being a condition which places a challenge to the organism, environmental change being the most likely.  Stress in turn would give rise to natural selection processes which would favour organisms with advantageous mutations.  So I'm guessing, again I'm not on solid ground here,  that evolution could occur without an externally arrived predator to light the blue touch paper.  Homegrown (evolved) predators would of course in turn eventually bring additional stress points and perhaps accelerate the natural selection process. 

 

Jim

Yeah I think that is a valid point as it would be perhaps more likely to be environmental .... although the frequency of external bodies hitting the earth carrying microbes that can survive the space journey might be plausable too... either way it could of been possible on both fronts and as we know , it had to on some fronts as we have arrived :p

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Just now, Greggy-spaceboy said:

Yeah I think that is a valid point as it would be perhaps more likely to be environmental .... although the frequency of external bodies hitting the earth carrying microbes that can survive the space journey might be plausable too... either way it could of been possible on both fronts and as we know , it had to on some fronts as we have arrived :p

Absolutely :) 

Jim 

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2 minutes ago, saac said:

I haven't came across the "external predator" theory before but I guess that evolutionary pressures are inevitable as they would arise from any "stress point" . A stress point being a condition which places a challenge to the organism, environmental change being the most likely.  Stress in turn would give rise to natural selection processes which would favour organisms with advantageous mutations.  So I'm guessing, again I'm not on solid ground here,  that evolution could occur without an externally arrived predator to light the blue touch paper.  Homegrown (evolved) predators would of course in turn eventually bring additional stress points and perhaps accelerate the natural selection process.

I agree, Jim.  My biology isn't that hot to be fair, but isn't this somewhat similar to the way that some organisms "absorbed" others that became mitochondria, to the benefit of both?

James

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6 minutes ago, JamesF said:

To deal with your model first, the universe does not necessarily have a radius of 45.6 billion light years.  The article you link to says it's the estimated current distance from us of the furthest galaxies we can observe (the light from which has taken 13.8 billion years to reach us).  It says nothing about the actual size of the universe.  It may be infinite.  Or perhaps it isn't.

Secondly, there is no specific "place" where the Big Bang happened.  It happened everywhere at once, and until it happened there wasn't really much of anywhere at all.  If you like, the Big Bang "created" space.  As the universe expands (as far as we know), everything is not moving away from some "centre", but moving away from everything else (there are exceptions to this).  The universe is not expanding to fill some pre-existing space.  This is not a particularly easy idea to get one's head around and isn't anywhere near as simple as the few sentences I've just used to describe it.

So, yes, I'm afraid your model is, as you say, "wrong on many levels".  There are some good books that try to explain it to people who don't do cosmology for a living though.  I quite like Simon Singh's "Big Bang", perhaps partly because he was a couple of years above me at school :) I believe Marcus Chown covers it in several books, too (and far more besides).

As regards the search for life, I don't think scientists currently care about evolutionary development time.  My understanding is that life is considered to have started very soon after the Earth cooled sufficiently.  That might suggest we got lucky, or it might suggest that life of some sort will start pretty much as soon as conditions allow.  Right now it would be a major leap forward to find any kind of life at all, so anything that looks like a planet capable of maintaining water in a liquid state, as was the case when life is believed to have started on Earth, is probably considered "of interest".

If you're after live that's multi-celled or has technological society then you might need to factor in evolutionary time, but whilst it would be fascinating I really don't think that's the primary goal right now.

James

Ah fair play I appreciate your response .... I suspected my understanding of the origins and development of the universe as we currently understand it are not understood yet fully by myself, (to be fair I only started to understand quantum mechanics last weekend) I will be sure to check out the book you reccomended. thank you

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9 minutes ago, Greggy-spaceboy said:

to be fair I only started to understand quantum mechanics last weekend

I am reminded of the quote widely attributed to Richard Feynman:

"If you think you understand quantum mechanics, you don't understand quantum mechanics."

:D

James

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