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Messages - Halc

Pages: [1] 2 3 ... 24
1
New Theories / Re: If there was one Big Bang event, why not multiple big bangs?
« on: 22/03/2023 13:33:37 »
Quote from: Bogie_smiles on 21/03/2023 20:40:55
once you find yourself alive
How can you find yourself anything but alive?
The following users thanked this post: Bogie_smiles

2
New Theories / Re: If there was one Big Bang event, why not multiple big bangs?
« on: 14/03/2023 19:22:36 »
Quote from: Bogie_smiles on 14/03/2023 17:03:32
I don't believe there is any irrefutable evidence though that says there was a beginning
There indeed is no irrefutable evidence of it. The big bang theory itself does not preclude it, but neither does it give any meaning to the phrase 'before the big bang'.
The following users thanked this post: Bogie_smiles

3
New Theories / Re: If there was one Big Bang event, why not multiple big bangs?
« on: 09/03/2023 07:12:04 »
Quote from: Dave Lev on 09/03/2023 05:48:21
I do recall that just few years ago, Halc claimed that Just after the Big Bang the entire Universe was in the size of a grapefruit. (I specifically remember the word - "grapefruit")
Too bad you didn't remember the other important words. It was the visible universe, and it was approximately that size (give or take an order of magnitude or two) after the inflation epoch, which came after the Planck epoch and Grand Unified epoch.

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When I have asked about the energy source for the Big Bang, the answer was: As there was no space and no time, there is no need to explain the BBT energy source.
I would not have said that. For one, it is unclear if there is any energy since the total energy density of the universe may be zero if you add in the negatives with the positives. But I think if you ask the experts, the concept of total energy density is meaningless. It's all relative, not absolute, so there's only comparisons with other states.

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Therefore, the time was ticking long before the Big Bang moment.
I would ask you to confine your assertions to your own topics. You're hijacking this topic, and continued wild assertions will get the posts moved or simply deleted.
This particular assertion seems to be an exception because Bogie already envisions bangs happening in existing space at assorted times now and then. This cannot work, but he doesn't care.

Other assertions (like the confusion of scientists or the uselessness of their theories) will get treated as a hijack. So behave when being a guest in somebody else's blog.
The following users thanked this post: Bogie_smiles, Zer0

4
New Theories / Re: If there was one Big Bang event, why not multiple big bangs?
« on: 28/02/2023 03:57:47 »
Quote from: Bogie_smiles on 28/02/2023 01:48:55
current Standard Cosmology, which I understand depicts finite space to be expanding
Current models do not posit finite space, but neither do they require infinite space. Most models presume space to be infinite.

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My question is, does the BB model refer to the action going on at the expanding boundary of the universe as creating space and matter out of nothingness?
No viable model posits a boundary to space, not even the ones with finite space.

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is it consistent to predict that  anti-space or negative space, and anti-matter are building up and exist beyond that expanding universe, in a sort of anti or negative universe?
There is no meaningful 'beyond space'. There might be other universes, but there wouldn't be a meaningful say direction in which they might be. If there was, it would just be a different but distant part of the same space. A type-1 multiverse is exactly that: Just locations in our space too distant to measure from Earth.
The following users thanked this post: Bogie_smiles, Zer0

5
Physics, Astronomy & Cosmology / Re: How Do We Know The Universe is 13.8B yrs Old If We Can Only See The Observable ?
« on: 25/02/2023 15:32:25 »
Quote from: neilep on 25/02/2023 14:36:25
How can we know it is 13.8 billion years old if all we can see is the observable Universe ?
The age was not computed by looking as far as we can see. Hubble's constant of about 70 km/sec/Mpc was measured nearly a century ago, long before they were looking at things a significant percentage of the distance to the edge of the observable universe. The age can be computed directly from just that one constant.

There's about 3e19 km in a Mpc, so 70 km/sec/Mpc is the same as 2.3e-18 km/sec/km which, cancelling the km part, is 2.3e-18 sec-1
The reciprocal of that is 4.35e17 seconds which is 13.8 billion years.
The following users thanked this post: neilep, Eternal Student

6
Physics, Astronomy & Cosmology / Re: If I Throw A Ball From The ISS, Will It Eventually Return From The Other Side
« on: 24/02/2023 16:48:34 »
Quote from: neilep on 24/02/2023 14:57:29
hrow a ball from the ISS in a way that it will return from the other side ?
Yes, it can be done.

If you throw a ball from the ISS at any time, it will return to the same spot (relative to Earth's inertial frame) each time. Trick is to get both the ISS and the ball to be at that spot at the same time.

Best way to do that is to have both come back after one orbit, which means the ball simply needs to move at the same speed relative to Earth as does the ISS, so just throw it (not hard) almost exactly perpendicular to its motion and it will come back in one orbit, and yes, from the other side.

Another way to to throw it forward really hard into a higher eccentric orbit and get it to orbit once when the ISS takes two trips around. Similarly, one could throw it to the front or rear but no so hard, in which case it will take many trips around before the two sync up, but it will come back always if you wait long enough.

Don't throw it to the rear too hard or it will drop into the atmosphere and konk a poor sheepy on the noggin.
The following users thanked this post: Zer0

7
New Theories / Re: What is the real readshift in the Cosmic Microwave Background (CMB)
« on: 08/02/2023 13:10:02 »
Quote from: evan_au on 08/02/2023 07:53:26
My simplistic understanding of what they said is:
- Roughly 15 (or 14) billion light years is the distance from "where the source was when the light was emitted" to "where we are now"
It's actually about 1/10000th of that. In cosmic coordinates (the only coordinate system I know that describes the universe), the oldest light we see (that of the CMB) was emitted at a proper distance of about 1.5 million LY away. The reason it took 13.8 billion years to get here is due to the very high expansion rate of the universe back at the time of the recombination event, perhaps 3M km/sec/mpc compared to 70 km/sec/mpc today.

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Roughly 100 billion light years is the distance from "where the source is now" to "where we are now"
That would put it beyond the size of the visible universe which means we could not see it. So around 45 billion light years is the proper distance from "where the source is now" to "where we are now".

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- There is an even smaller number which represents the distance from "where the source was when the light was emitted" to "where we were back then"
Well since we have not moved significantly in that time, that distance is also that 1.5 MLY figure. Cosmic coordinates has the Earth at the center, unmoving. You have to assign the origin somewhere.

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As relativity illustrated, all times and distances are relative to which frame of reference you are talking about
Yes, which is why I carefully specified the cosmic frame and not say some inertial frame, which isn't valid at all at large distances since spacetime isn't Minkowskian.

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And anything outside your light cone is irrelevant to you (eg if some object is now 100 billion light-years away, light from that object will probably never reach us, due to the expansion of the universe).
Correct. Any recombination light emitted from what is currently over about 58 BLY away will never reach us. Any light emitted today from over 16 BLY away will also never reach us. That latter figure is the current distance to the event horizon.
The following users thanked this post: evan_au

8
Physics, Astronomy & Cosmology / Re: As The Andromeda galaxy gets Closer Do We See It Younger ?
« on: 03/02/2023 21:32:00 »
Quote from: neilep on 03/02/2023 17:49:42
Because we are not moving towards each other at the speed of light will it not appear younger as it gets closer because the light from it is travelling a lot faster than it is travelling towards us ?
Actually, I fixed my first post. The faster something comes at you, the faster it appears to age. Andromeda appears to age an extra hour every 3 months of us watching it. If something approaches us near speed of light, it can appear to age twice as fast, or a thousand or more times. This is mostly due to Doppler effect. Things moving away appear to age more slowly, so those really distant galaxies are very young looking because their appearance has had no time to age them beyond their lambdom.

Spell checker didn't like that word. Not sure why not.
The following users thanked this post: Zer0

9
Physics, Astronomy & Cosmology / Re: As The Andromeda galaxy gets Closer Do We See It Younger ?
« on: 03/02/2023 15:27:17 »
Quote from: neilep on 03/02/2023 13:54:47
So, as Andromeda gets closer will we be bale to see it get younger as the light won't need to travel so far is not it ?
No. It will always appear to be aging forward (faster than us even), so in a year it might appear a year plus 4 hours older..
The following users thanked this post: neilep

10
New Theories / Re: If there was one Big Bang event, why not multiple big bangs?
« on: 02/02/2023 02:05:29 »
Quote from: Zer0 on 29/01/2023 22:29:51
The Observable Edge of the Universe is drifting away FTL, Correct?
The size (radius say) of the observable universe is growing at a proper rate of a bit over 3c, and accelerating.

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So if there ever was to be a new BB at the Farthest Edge of the Universe, how would/could We Observe it?
It just plain doesn't make sense for a big bang to occur at a location.  Also, there is no meaningful edge of the universe. I cannot think of a viable model that has one.

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If WE cannot Observe/Measure it & there ain't no Data/Evidence for it, does it then mean it's Not Real?
By many definitions of 'is real', correct. Careful, since there is a distinction between measuring something and knowing about it. The latter implies nothing can be real without something that can 'know' about it. The measurement definition is simply any interaction between two systems.

Quote from: Bogie_smiles on 02/02/2023 01:51:21
I'd say no, though you do need some evidence to support a theory.
That you do, but a definition of 'real' isn't a theory, it's just a definition. The whole concept of 'real' is a metaphyscial one, so I don't think it is possible to produce conclusive evidence for a metaphysical conjecture. If one could, it would be a theory and cease to be metaphysics.
The following users thanked this post: Bogie_smiles

11
General Science / Re: Why Does Making A Sandwich Enable Ewe To Cut Anything?
« on: 01/02/2023 19:22:48 »
Well for one, the only people I've known to cut the cheese do so between two buns.

That out of the way, it's probably because the hoagie roll provides a nice dry handle of sorts, providing a nice reaction force to what the knife is doing. Sans roll, you'd have to get the slimy parts all over the trotters, far more difficult to hang on.
The following users thanked this post: neilep

12
New Theories / Re: If there was one Big Bang event, why not multiple big bangs?
« on: 21/01/2023 00:11:08 »
Quote from: Bogie_smiles on 20/01/2023 18:09:44
I've forgotten how to post images (I'm getting old :( )
It looks like the death star:

"That's no moon. Oh wait, it's a moon"

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I would say that it looks like it covers about 25% of the diameter of the Mimas
Close enough. I get 30% of the diameter, or about 10% of the circumference, which makes it cover maybe 3% of the surface, a slight reduction of my prior estimate.

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... as seen from Saturn.
Although most images including the one I posted are not from Saturn. Most are as seen from Earth, as evidenced by the fact that we see most of the daylight side.

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Probably much smaller than the diameter of the impact crater of our dinosaur killing asteroid ...?
The Mimas crater is about 130 km across, whereas the Chicxulub crater (Yucatan) is about 150 km across, larger, but not much larger. It's the second largest crater on Earth, with Vredefort being a bit bigger, in South Africa.

There's no trace of the Theia impact structure since that was a melt-the-whole-thing-and-start-over sort of deal. It would not be meaningful to say 'here's the spot where it hit'.

Quote from: Zer0 on 19/01/2023 17:14:56
But how come the Search Information says Confirmed vs Provisional?
The provisional ones have not had their sightings or orbits yet confirmed. They might just be a passing object and not in orbit at all.

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So WE still aren't Sure how many exact Moons they have?
No, they're really far away and it's awful dark out there, and some of these things are pretty tiny. There must be a threshold of what constitutes a moon vs just a small pebble that happens to be in orbit about something.

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Juno & Voyager did take a closer look, Right?
Yes, and they found/confirmed a bunch, but the didn't linger long enough to do a thorough scan of the area. Juno didn't make it to Saturn either.

Quote from: Zer0 on 19/01/2023 17:14:56
Thanx Hal for setting me straight...Again!
OK, so setting you even more straight, I'm Halc (rhymes with 'false'). There is another user (occasional poster) on this site whose ID is Hal. I'm not him.

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Roger Penrose imagined a Cyclical Universe, isn't it?  So why'd he do dat?
Try something different? Hard to say what he suggests, but it seems like it is playing with conformal time. The view requires infinite time to pass as measured by one bang before the next one happens, and it is unclear if it allows the bang to have any energy associated with it. The bangs still happen everywhere, which is the same as nowhere given infinite time and spacetime becomes singular in a way.
The following users thanked this post: Bogie_smiles

13
New Theories / Re: If there was one Big Bang event, why not multiple big bangs?
« on: 19/01/2023 03:24:22 »
Quote from: Bogie_smiles on 17/01/2023 01:35:20
I don't have the knowledge or background to qualify me to solve the kinds of problems that the scientific community is dealing with.
I'm not talking about the problems of the scientific community. I'm talking about the problems with bangs happening here and there. You seem to evade them, as does say a theist when confronted with contradictory evidence. Their goals are not scientific ones so they don't mind contradictions.


Quote from: Bogie_smiles on 18/01/2023 20:14:50
"the Herschel crater" covers nearly a quarter of Mimas' surface
5% at best, about a 20th. Still dang impressive.

Mimas orbits Saturn, not Jupiter.

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I wonder if that kind of impact, from a different angle, could throw the small moon out of orbit and into a collision path with Earth?
It would need to be accelerated anywhere from 6 to 35 km/sec (depending on direction of acceleration) to leave orbit. Anything that hit hard enough to accelerate it that much would shatter it into gravel. Much would fall into Saturn, but some of the fragments would find their way to the orbits of the other planets.
The following users thanked this post: Bogie_smiles

14
New Theories / Re: If there was one Big Bang event, why not multiple big bangs?
« on: 16/01/2023 22:19:41 »
Quote from: Zer0 on 11/01/2023 16:19:53
Can the Above Image, thru Wild Speculative Imagination, depict a Cyclical or Splitting Universe/s?
It's a bifurcation diagram, which comes from chaos theory, showing modes of stability, chaos, and strange attractors. Among other things, it's a nice fractal. And yea, it's not what Zero might wildly speculate it to be.

Quote from: Bogie_smiles on 06/01/2023 02:07:55
Quote from: Halc on 05/01/2023 00:38:31
The 'here and there' part is particularly problematic.
I consider the "here and there" idea as a hypothetical assertion associated with the multiple Big Bang premise. That premise, as I imagine it, has only one infinite space, so multiple big bangs all occur in that one space, in different places in that space, from time to time.
Yes, you've repeated that a great many times, but you edited out the important part of my post: "Have you given thought as to resolving the problems instead of ignoring them?"

Quote from: Bogie_smiles on 10/01/2023 00:23:10
I'm looking at an old copy of Astronomy magazine and the lead story is "Our trillion-galaxy universe".
Another loose usage of the term 'universe', typical of a pop publication. Doubtless they mean the visible universe. There are an estimated 2 trillion galaxies in this volume, depending heavily on which ones get counted and when.

The following users thanked this post: Bogie_smiles, Zer0

15
Physics, Astronomy & Cosmology / Re: What is the exact cause of the time dilation of the twin?
« on: 15/01/2023 16:19:16 »
Quote from: Dimensional on 12/01/2023 04:05:21
Quote from: Halc on 12/01/2023 00:01:46
It's not a function of acceleration, so I cannot say from just that.
Then would you say that Sabine in the video is wrong?
I am actually going to go so far as to say exactly that. I caution against taking a simple comment out of context, and I'm not much on clicking videos and actually watching them (21 minutes to wade through), and it's Sabine, so I presumed the content is accurate. Well it isn't, which is a shame.

At 0:40 she complains about trying to learn relativity from pop-science sources and failing or finding them incorrect. Many are. Here she is creating her own pop-science tutorial and she does the same thing: get it wrong.

At 1:45 she gets into the length of the path between two sets of coordinates, correctly pointing out that different paths are different lengths despite the beginning and end of the paths being the same, as it is in the twins scenario.

At 6:50 she shows how the calculation of the temporal length of an arbitrary path can be done by breaking the path into pieces and integrating over the length of the path. This is what Eternal Student has done in post 16:
Quote from: Eternal Student on 13/01/2023 02:39:44
Quote from: Dimensional on 12/01/2023 19:10:41
Do you know any math formulas to see how acceleration and time dilation are related?

the elapsed time for the travelling twin (who goes to Andromeda) is given by:

Δτ =  19ebf56c768e97b65a9b5f4bc1f3f173.gif 
[Eqn 2]
The computation above is completely scalar. Note the complete lack of acceleration reference in the formula. I see time and speed (v) and that's it. It isn't a function of acceleration, as I said above. The formula above is from special relativity, so it only applies to the special case where gravity is not involved. Hossenfelder's video is entitled "Special Relativity: This Is Why You Misunderstand It", which means the content should stay away from gravity, or the video is mistitled.

And what's with Andromeda? Sure, with enough acceleration, Bob can get there and back before he dies, but Alice (and the whole human race for that matter) isn't going to be there upon his return. Sabine should pick a closer target.

Back to the video:
At 11:00 we get into the twins thing and she correctly says that at least one of the twins needs to accelerate to turn around. That's a biased way of putting it, but true. More correctly, at least one of them needs to accelerate in order for their paths to diverge but meet up a second time. Without acceleration, any relative velocity will just have them meet once at best and forever diverge after that. But it isn't the acceleration that causes the dilation, it is the relative temporal lengths of the paths they take, as computed by the above formula.

11:25 She says acceleration is absolute. She means proper acceleration (the kind you feel with an accelerometer) is absolute. Coordinate acceleration is relative to some coordinate system and is thus not absolute. So sitting at your computer reading this, your coordinate acceleration (relative to your house maybe) is stationary, but your proper acceleration is 1g upward because that's how hard the chair under you is accelerating you.

12:52 She correctly points out that the twins scenario has nothing to do with gravity.

13:39 She correctly points out that the twins starting and ending with the same velocity is not necessary (except to explain that they're twins and presumably had reasonably identical velocity at birth. They merely have to meet twice.

15:30 We start getting into gravity, which is out of scope for a video entitled "Special relativity". She starts with pointing out that under Einstein, gravity is not a force. It is in fact spacetime which has a geometery other than flat Minkowskian spacetime. So anything not accelerating (has no force acting on it) follows a geodesic along the local spacetime.

16:55 She first says acceleration causes time dilation. This is blatantly wrong. Contradictions follow.
17:50 Things really start falling apart. The time runs slower at sea level than on a mountain due to greater acceleration at sea level. This is completely wrong. If true, clocks would run fastest at the center of Earth where acceleration would be zero, but they in fact run slowest there than anywhere else on Earth. The acceleration on the surface of Mercury is under 40% of that on Earth, but time on Mercury runs slower, directly contradicting what Sabine is saying.

19:25 She asks if her video was any better than those incomprehensible books from way back? Well it would be if she hadn't mucked it up.

Back to Special relativity, since I want to disassemble her treatment of that as well and not just her botching the gravity bit. A couple examples contradicting her assertions:

Example 1) Alice, Bob and Chuck are triplets and age 20. Alice stays home. Bob and Check set out on a trip and accelerate identically (10g say) for a month and then coast, riding side by side for a while.  After a year on his own clock, Bob accelerates towards Earth at 10g for 2 months, going back towards home at the same speed he went out. He coasts for another year and takes a month to stop. He's aged 2 years coasting and 4 months acceleration and is age 22y4m now and finds Alice at age 23y2m, or 10 months older. They wait together for Chuck to come back.
Chuck coasts twice as long and turns back. So he ages 4 years coasting and the 4 months accelerating and comes home at age 24y4m finding Alice to be 25y5.7m and Bob to be 24y7.7m.
This contradicts what Hossenfelder says since both Bob and Chuck have experienced identical accelerations, just at different times. They should be aged identically per Hossenfelder's words, but they're not. This is one trouble with doing physics in the language of laymen instead of the language of physcs. Time dilation is not a function of acceleration and there's no mathematical formula expressing it in terms of acceleration.

Example 2)
I have a pair of wheels or gears. One wheel is 1000 times the radius of the other, and they meet at one point and move at the same velocity there. I put a clock on each wheel at the point at which they meet. The wheels get turned with the small  one going around at 1000 times the RPM and hence 1000 times the centripetal acceleration. Both clocks are moving at the same speed relative to the inertial frame of the setup. The two clocks will stay in sync indefinitely despite the one acceleration being a thousand times the other. This also contradicts what Hossenfelder says in the video, but is entirely consistent with the formula that ES provided.
The following users thanked this post: Zer0, Origin

16
Plant Sciences, Zoology & Evolution / Re: Snakes vision of heat to them is in shades of blue and yellow?
« on: 09/01/2023 18:20:23 »
Quote from: Europan Ocean on 09/01/2023 16:48:09
I have heard that animals like dogs and cats see light in shades of blue and yellow.
Many mammals have cones in their eyes sensitive to these colors, yes. Two is common. I've heard of as many as 16 colors (giving 256 primary colors), but not in a mammal species.

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I have heard snakes see infra red light, but in shades of blue and yellow or yellow and red...?
Most snakes are sensitive to green and blue, but some use IR (yes, through the pits) to detect prey.  Mosquitoes and vampire bats have decent IR vision. It's a good thing for a blood sucking species to have. Mosquito's best sense is probably that of CO2.

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What goes on in their retinas and brains?
The retinas are just like any other, but with cones sensitive to different wavelengths than others. As for the brain, one can't say how any of these colors are perceived. Some creature (maybe even another person) might be sensitive to the same colors as you, but perceive them completely differently.
The following users thanked this post: Zer0

17
New Theories / Re: If there was one Big Bang event, why not multiple big bangs?
« on: 05/01/2023 00:38:31 »
Quote from: Bogie_smiles on 04/01/2023 23:12:39
On the other hand, fitness of the higher orders, like modern humans, is at a level where survival of the fittest includes competition for scarce resources in the wild
Humans don't do particularly well 'in the wild'. Our forte, as well as our downfall, is the cooperation among large groups (civilization). Take that away and it will be surprising if we can keep our population as high as a thousandth of what it is now. The holocene extinction event is in full swing right now, expecting to eliminate something like 75% of all species. Will humans be part of the 25% that survives? It's questionable, and that makes us not so 'high order'.

Quote from: Bogie_smiles on 04/01/2023 22:44:29
one of a potentially infinite number of similar Big Bang events, occurring now and then, here and there, across time and space.
That's just a premise, and one that leads to contradictions that have been identified. Have you given thought as to resolving the problems instead of ignoring them?  The 'here and there' part is particularly problematic.
The following users thanked this post: Bogie_smiles

18
Physiology & Medicine / Re: Quantum Manifestation Code Review
« on: 30/12/2022 17:27:53 »
Quote from: paul cotter on 30/12/2022 16:58:30
I wanted to ask the same question but couldn't find the requisite motivation.
And you shall not be receiving an answer. This poster was just advertising his site and posting the same stuff on several other forums and social media sites.
It's not billed as a new theory and not phrased as a question, so it violates 3-4 rules already.
The following users thanked this post: Zer0

19
New Theories / Re: If there was one Big Bang event, why not multiple big bangs?
« on: 27/12/2022 03:16:17 »
Quote from: Bogie_smiles on 27/12/2022 02:19:47
When the survival of the fittest is achieved,
Survival of the fittest is a means to a process, not a goal that is 'achieved'.
Intelligence seems to not be a very fit trait, similar to a disease that is so effective that it kills all its potential hosts. Point is, most planets with life will likely not be found with intelligent beings on it at any given time since their duration is an incredibly short interval.
The following users thanked this post: Bogie_smiles

20
New Theories / Re: If there was one Big Bang event, why not multiple big bangs?
« on: 20/12/2022 20:56:49 »
Quote from: Bogie_smiles on 20/12/2022 14:03:16
even a planet killer asteroid would be unlikely to destroy all life.
The biggest hit Earth has ever taken (the Theia event) may or may not have happened before there was life, but it if was already there, it was not wiped out by it. I agree, an asteroid is probably not up to the job, but the coming warming (in a billion years or so) will boil away all water and make the planet uninhabitable for multicellular life. Life will survive this in simple form for several more billion years until the sun grows enough to possibly swallow Earth if it doesn't move far enough away in that time.

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I could see a huge chunk of Earth having enough gravity to be planet like, and to host some form of life to start the process over again as it finds a new star or planet out there to orbit around.
It doesn't take a large chunk or gravity at all. Any rock big enough to not be completely destroyed by falling on another host planet can transport dormant life to it. There's a reasonable probability that life originated on some other planet and only got here via such a calamity to the original world. Something lived inside a rock for aeons in space and was deep enough to not be burnt to a crisp on entry into our atmosphere. Then only a few centuries of erosion lets the life out of the rock and bingo, we have life here that originated elsewhere. How it subsequently evolved into the life we know is definitely still a product of Earth's environment which is very likely completely different than the world from which that rock was ejected.
The following users thanked this post: Bogie_smiles, Zer0

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