11
The Fermi Paradox
Kypickle
madamepestilence
The Fermi Paradox is probably one of the most mysterious scientific concepts ever. It's about aliens.
The Universe is 13.8 billion years old. Life has been able to exist in the universe for probably 11 billion of those years, or about the entire lifetime of our milky way so far. Earth has existed for 4.5 billion years, and life on Earth has existed for 4 billion years. That leaves 7 billion years, where Earth didn't even exist yet, where life could've existed in our galaxy, and in the universe. Billions of years for civilizations to rise and reach up to the stars.
It is theorized that one civilization going slower than light can colonize the entire milky way galaxy in 10 million years. Meaning, a civilization could've colonized the entire milky way 700 times over, before earth even existed. To make this weirder, we keep finding more and more earthlike planets that could potentially support life, like in the TRAPPIST-1 system, which is double the age of the solar system and has 3 earth-sized planets with confirmed water. So much time for a civilization to colonize our entire galaxy. But we see nothing. No aliens. No contact. The Great Silence. Which brings us to the question...
Where are all the aliens?
We should see one gigantic super-civilization in control of our entire galaxy, or we should see hundreds of other civilizations. But we don't. Our galaxy is silent. We seem to be the only one.
That is the Fermi Paradox. Where are the aliens? There are multiple theories:
-The Great Filter
-The Rare Earth Hypothesis
-The Zoo Hypothesis
and quite literally hundreds of other potential solutions to this paradox. But none can quite explain what we see. So, I ask you this:
What do you think the answer to the Fermi Paradox is?
The Universe is 13.8 billion years old. Life has been able to exist in the universe for probably 11 billion of those years, or about the entire lifetime of our milky way so far. Earth has existed for 4.5 billion years, and life on Earth has existed for 4 billion years. That leaves 7 billion years, where Earth didn't even exist yet, where life could've existed in our galaxy, and in the universe. Billions of years for civilizations to rise and reach up to the stars.
It is theorized that one civilization going slower than light can colonize the entire milky way galaxy in 10 million years. Meaning, a civilization could've colonized the entire milky way 700 times over, before earth even existed. To make this weirder, we keep finding more and more earthlike planets that could potentially support life, like in the TRAPPIST-1 system, which is double the age of the solar system and has 3 earth-sized planets with confirmed water. So much time for a civilization to colonize our entire galaxy. But we see nothing. No aliens. No contact. The Great Silence. Which brings us to the question...
Where are all the aliens?
We should see one gigantic super-civilization in control of our entire galaxy, or we should see hundreds of other civilizations. But we don't. Our galaxy is silent. We seem to be the only one.
That is the Fermi Paradox. Where are the aliens? There are multiple theories:
-The Great Filter
-The Rare Earth Hypothesis
-The Zoo Hypothesis
and quite literally hundreds of other potential solutions to this paradox. But none can quite explain what we see. So, I ask you this:
What do you think the answer to the Fermi Paradox is?
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29
4
- Are there different types of black holes?
- Can a star turn into a planet?
- Can gravity form waves?
- Does every black hole contain a singularity?
- Does sound travel faster in space?
- Does the influence of gravity extend out forever?
- Galaxies look stationary, so why do scientists say that they rotate?
1
[I realize you've already received a response from OP but I just wanted to provide my own input :) Forewarning for very lengthy, complicated answers, and a mess of links at the bottom.]
1. Are there different types of black holes?
There are, in fact, many types of black holes. All black holes spin when they're created due to the fact that stars, as well as all celestial objects, have a spin of their own, and this spin's torque is greatly accelerated to near lightspeed when converted to a neutron star or black hole. Black holes also have electric charges that differ with every black hole. Black holes with no spin and no electric charge do not, and cannot exist with our current understanding of physics, and are only presented as such when working purely theoretically due to the fact that spin and electric charge significantly complicate the math required to understand black holes.
The proposals for the specifics of how black holes function is a matter of debate. In November 1784, John Michell first coined the idea of a celestial body so massive that nothing could escape it, calling them "dark stars," and simulating them with very simple (relative to modern) equations, correctly theorizing that they would be detectable by their effects on gravitational fields surrounding them, but enthusiasm quickly died out after light was discovered to be a wavelength (although later discovered to also be a particle simultaneously much later; see Quantum Physics*, Quantum Superposition**, Photons***, Wave-Particle Duality****, Double-Slit Experiment****) in the nineteenth century.
The Double Slit Experiment
It took until Albert Einstein hypothesizing the Theory of General Relativity† in 1915 to prove that black holes were possible due to gravity being able to affect light wavelengths, and Karl Schwarzschild later discovered the final solutions to Einstein's field equations, determining the gravitational fields of point mass and spherical mass. Schwarzschild and Johannes Droste both came up with the same answer to point mass gravitational fields, discovering what is now known as the Schwarzschild radius††, otherwise known as the event horizon (point of no return) of a black hole. This led to the proposed Schwarzschild Black Hole††† solution to black hole formation (a spherical, symmetrical black hole), resulting in the solutions to Einstein's equations being infinite, which was not greatly understood.
Schwarzschild Black Hole
In 1924, Arthur Eddington proved the singularity disappeared after a change of coordinates (Eddington-Finkelstein coordinates††††), and in 1933, Georges Lemaître discovered that the singularity at the centre of the Schwarzschild radius was non-physical. Two years prior to Lemaître in 1931, Subrahmanyan Chandrasekhar discovered (using Einstein's Theory of Special Relativity†††††) that a non-rotating body above 1.4 M☉ (where M☉ is the Mass of our star, Sol), now known as the Chandrasekhar limit, has no stable solutions, and is therefore not possible. This was disputed by Eddington, Lev Landau, and Robert Oppenheimer (who predicted that neutron stars above the Tolman-Oppenheimer-Volkoff limit‡ would collapse into black holes, in 1939, despite this being dependent on the mass of cold, non-rotating neutron stars) - nowadays, the TOV limit has been refined to ~2.17M☉ thanks to studies of the neutron star merger GW170817, which is believed to have become a black hole post-merging.
Over the years, various solutions to the modern understanding of black holes (there is a much more extensive history‡‡) have come up, which include:
The Schwarzschild Solution
The Reissner-Nordström Solution‡‡‡
The Gödel Solution‡‡‡‡
The Kerr Solution‡‡‡‡‡
The Kerr-Newman Solution§
The Kasner Solution§§
The Lemaître–Tolman Solution§§§
The Taub-NUT Solution§§§§
The Milne Solution§§§§§
The Friedmann–Lemaître–Robertson–Walker (FLRW) Solution‖
The plane-fronted waves with parallel propagation (pp-wave) Solution‖‖
The van Stockum dust Solution‖‖‖
The Weyl–Lewis–Papapetrou Solution‖‖‖‖
Relative to each other, however, black holes only have three defining features: mass, electric charge, and angular momentum - they are otherwise identical and indistinguishable from each other. This makes them much like stellar mass versions of electrons - while all are different, when compared together, they are all essentially identical from external view.
If you'd like a very simplified view of how black holes work, I'd recommend Kurzgesagt's information uploaded to their YouTube channel.(¶, ¶¶, ¶¶¶, ¶¶¶¶, ¶¶¶¶¶, #)
Generally though, black holes are separated into four main categories:
Supermassive Black Holes (these are widely believed to be the cores of all galaxies; 105-1010 M☉)
Intermediate-Mass Black Holes (103 M☉)
Stellar-Mass Black Holes (10 M☉)
Micro Black Holes (up to MMoon, where Moon is in relevance to Earth's Moon's mass)
There is also hypothetical Primordial Black Holes, which are black holes that may have formed shortly after the formation of the universe.
A Very Beautiful Artistic Rendition of Black Hole Anatomy
2. Can a star turn into a planet?
Yes, but this can only occur with stars known as Brown Dwarfs##, ###, which are considered too massive to technically to be planets, but have too little mass to technically be stars, making them an odd sort of middle ground. They're incapable of burning regular hydrogen (H²), and can consequently only burn their heavy hydrogen (²H), usually known as deuterium.#### This results in the brown dwarf using up all of its fuel very quickly, and it consequently cools into a planet.
3. Can gravity form waves?
Gravity is, in fact, already a wavelength! Gravity is a wavelength of spacetime created by mass, telling spacetime around it how to warp. Essentially, gravity is a wavelength of spacetime. This is also the reason that light is drawn in to black holes: photons are outside of spacetime (as travelling at the speed of light results in time being completely frozen relative to lightspeed according to Einstein's Theory of Special Relativity), resulting in the photon travelling in a straight line along the curvature of spacetime, as, from the photon's point of view, this is the fastest way to travel from point A to point B, while from our perception the path of light is being warped.
A Visualization of a Wavelength Interacting with Spacetime Warping in Sol (on a 2D Plane)
4. Does every black hole contain a singularity?
Technically, no black holes contain a singularity, as this would correlate only to theoretical, impossible, black holes with no rotation. The mass at the relative centre of the black hole would be spread out into a toroid (donut-like) shape, known as a ringularity. This ringularity will still take up zero space in the three dimensions, simultaneously being a ring of mass and a 1-dimensional point. It's very complicated at this level, and some even theorize that the solution to the black hole information paradox##### is that all matter is trapped at the edge of the event horizon, pressed completely flat in 2D form across the 3D bubble. (Explained in the ¶¶¶ link)
5. Does sound travel faster in space?
Sound is incapable of travelling in space. Sound requires atoms to travel through, as it's essentially a pressure wave. It may not seem like it, but our own atmosphere is a very thick soup of atoms, while space usually has an average of only 10 or so atoms per every square foot. However, it's a perfect medium for light to travel through relatively unhindered, which is why radio (light underneath our visual spectrum, below infrared) and microwave (light above our visible spectrum, above ultraviolet, but not as high as gamma) are ideal forms of communication in space.
6. Does the influence of gravity extend out forever?
Yep! You are affected by an atom on the edge of the universe, and vice versa - the influence of gravity just becomes weaker the further out other objects with mass are, and objects with more mass have stronger gravitational effects than objects with less mass, resulting in objects with less mass being influenced by objects with larger mass. This is why we're plastered to the surface of the Earth, which orbits Sol while Luna (Earth's Moon) orbits Earth, while Sol, alongside all other celestial objects in the Milky Way, orbit Sagittarius A* (not a link, the asterisk is part of the supermassive black hole's name), and so on and so forth with areas of increasing mass ad infinitum.
7. Galaxies look stationary, so why do scientists say they rotate?
The movement of the universe is limited by an integral factor: the speed of light. This is why larger organisms tend to move slower relative to smaller organisms. Mass can only travel so quickly. Consequently, despite galaxies rotating extremely fast (for instance, the Milky Way orbits at 130 miles per second in our stellar neighborhood, slower closer to Sagittarius A*, and faster further out near the ends of the galaxy's arms due to how torque works - TLDR, the further out something is from a moving object, the faster it will move until it reaches its relative speed barrier), we're unable to perceive their rotation easily due to how slowly they rotate in comparison to their size.
* A Wikipedia Article on Quantum Physics
** A Wikipedia Article on Quantum Superposition
*** A Wikipedia Article on Photons
**** A Wikipedia Article on Wave-Particle Duality
***** A Wikipedia Article on the Double-Slit Experiment
† A Wikipedia Article on General Relativity
†† A Wikipedia Article on the Schwarzschild Radius
††† A Wikipedia Article on the Schwarzschild Solution to Black Holes
†††† A Wikipedia Article on Eddington-Finkelstein Coordinates
††††† A Wikipedia Article on Special Relativity
‡ A Wikipedia Article on the Proposed Tolman-Oppenheimer-Volkoff Limit
‡‡ A Wikipedia Article on Black Holes (you will find many of the aforementioned links here)
‡‡‡ A Wikipedia Article on the Reissner-Nordström Solution to Black Holes
‡‡‡‡ A Wikipedia Article on the Gödel Solution to Black Holes
‡‡‡‡‡ A Wikipedia Article on the Kerr Solution to Black Holes
§ A Wikipedia Article on the Kerr-Newman Solution to Black Holes
§§ A Wikipedia Article on the Kasner Solution to Black Holes
§§§ A Wikipedia Article on the Lemaître–Tolman Solution to Black Holes
§§§§ A Wikipedia Article on the Taub-NUT Solution to Black Holes
§§§§§ A Wikipedia Article on the Milne Solution to Black Holes
‖ A Wikipedia Article on the FLRW Solution to Black Holes
‖‖ A Wikipedia Article on the pp-wave Solution to Black Holes
‖‖‖ A Wikipedia Article on the van Stockum dust Solution to Black Holes
‖‖‖‖ A Wikipedia Article on the Weyl–Lewis–Papapetrou Solution to Black Holes
¶ Kurzgesagt's First Video on Black Holes from 7 Years Ago, Regarding Miniature Black Holes
¶¶ Kurzgesagt's First Black Hole Explanation Video from 6 Years Ago
¶¶¶ Kurzgesagt's Second Black Hole Explanation Video from 5 Years Ago
¶¶¶¶ Kurzgesagt's Video on Black Hole Bombs
¶¶¶¶¶ A More Up-To-Date Kurzgesagt Video on Black Holes
# A Kurzgesagt Video on Known Large Black Holes (Size Comparison)
## A Wikipedia Article on Brown Dwarfs
### A Kurzgesagt Video on Universal Size Comparisons (Includes Brown Dwarfs)
#### A Wikipedia Article on Deuterium
##### A Wikipedia Article on the Black Hole Information Paradox
1. Are there different types of black holes?
There are, in fact, many types of black holes. All black holes spin when they're created due to the fact that stars, as well as all celestial objects, have a spin of their own, and this spin's torque is greatly accelerated to near lightspeed when converted to a neutron star or black hole. Black holes also have electric charges that differ with every black hole. Black holes with no spin and no electric charge do not, and cannot exist with our current understanding of physics, and are only presented as such when working purely theoretically due to the fact that spin and electric charge significantly complicate the math required to understand black holes.
The proposals for the specifics of how black holes function is a matter of debate. In November 1784, John Michell first coined the idea of a celestial body so massive that nothing could escape it, calling them "dark stars," and simulating them with very simple (relative to modern) equations, correctly theorizing that they would be detectable by their effects on gravitational fields surrounding them, but enthusiasm quickly died out after light was discovered to be a wavelength (although later discovered to also be a particle simultaneously much later; see Quantum Physics*, Quantum Superposition**, Photons***, Wave-Particle Duality****, Double-Slit Experiment****) in the nineteenth century.
The Double Slit Experiment
It took until Albert Einstein hypothesizing the Theory of General Relativity† in 1915 to prove that black holes were possible due to gravity being able to affect light wavelengths, and Karl Schwarzschild later discovered the final solutions to Einstein's field equations, determining the gravitational fields of point mass and spherical mass. Schwarzschild and Johannes Droste both came up with the same answer to point mass gravitational fields, discovering what is now known as the Schwarzschild radius††, otherwise known as the event horizon (point of no return) of a black hole. This led to the proposed Schwarzschild Black Hole††† solution to black hole formation (a spherical, symmetrical black hole), resulting in the solutions to Einstein's equations being infinite, which was not greatly understood.
Schwarzschild Black Hole
In 1924, Arthur Eddington proved the singularity disappeared after a change of coordinates (Eddington-Finkelstein coordinates††††), and in 1933, Georges Lemaître discovered that the singularity at the centre of the Schwarzschild radius was non-physical. Two years prior to Lemaître in 1931, Subrahmanyan Chandrasekhar discovered (using Einstein's Theory of Special Relativity†††††) that a non-rotating body above 1.4 M☉ (where M☉ is the Mass of our star, Sol), now known as the Chandrasekhar limit, has no stable solutions, and is therefore not possible. This was disputed by Eddington, Lev Landau, and Robert Oppenheimer (who predicted that neutron stars above the Tolman-Oppenheimer-Volkoff limit‡ would collapse into black holes, in 1939, despite this being dependent on the mass of cold, non-rotating neutron stars) - nowadays, the TOV limit has been refined to ~2.17M☉ thanks to studies of the neutron star merger GW170817, which is believed to have become a black hole post-merging.
Over the years, various solutions to the modern understanding of black holes (there is a much more extensive history‡‡) have come up, which include:
The Schwarzschild Solution
The Reissner-Nordström Solution‡‡‡
The Gödel Solution‡‡‡‡
The Kerr Solution‡‡‡‡‡
The Kerr-Newman Solution§
The Kasner Solution§§
The Lemaître–Tolman Solution§§§
The Taub-NUT Solution§§§§
The Milne Solution§§§§§
The Friedmann–Lemaître–Robertson–Walker (FLRW) Solution‖
The plane-fronted waves with parallel propagation (pp-wave) Solution‖‖
The van Stockum dust Solution‖‖‖
The Weyl–Lewis–Papapetrou Solution‖‖‖‖
Relative to each other, however, black holes only have three defining features: mass, electric charge, and angular momentum - they are otherwise identical and indistinguishable from each other. This makes them much like stellar mass versions of electrons - while all are different, when compared together, they are all essentially identical from external view.
If you'd like a very simplified view of how black holes work, I'd recommend Kurzgesagt's information uploaded to their YouTube channel.(¶, ¶¶, ¶¶¶, ¶¶¶¶, ¶¶¶¶¶, #)
Generally though, black holes are separated into four main categories:
Supermassive Black Holes (these are widely believed to be the cores of all galaxies; 105-1010 M☉)
Intermediate-Mass Black Holes (103 M☉)
Stellar-Mass Black Holes (10 M☉)
Micro Black Holes (up to MMoon, where Moon is in relevance to Earth's Moon's mass)
There is also hypothetical Primordial Black Holes, which are black holes that may have formed shortly after the formation of the universe.
A Very Beautiful Artistic Rendition of Black Hole Anatomy
2. Can a star turn into a planet?
Yes, but this can only occur with stars known as Brown Dwarfs##, ###, which are considered too massive to technically to be planets, but have too little mass to technically be stars, making them an odd sort of middle ground. They're incapable of burning regular hydrogen (H²), and can consequently only burn their heavy hydrogen (²H), usually known as deuterium.#### This results in the brown dwarf using up all of its fuel very quickly, and it consequently cools into a planet.
3. Can gravity form waves?
Gravity is, in fact, already a wavelength! Gravity is a wavelength of spacetime created by mass, telling spacetime around it how to warp. Essentially, gravity is a wavelength of spacetime. This is also the reason that light is drawn in to black holes: photons are outside of spacetime (as travelling at the speed of light results in time being completely frozen relative to lightspeed according to Einstein's Theory of Special Relativity), resulting in the photon travelling in a straight line along the curvature of spacetime, as, from the photon's point of view, this is the fastest way to travel from point A to point B, while from our perception the path of light is being warped.
A Visualization of a Wavelength Interacting with Spacetime Warping in Sol (on a 2D Plane)
4. Does every black hole contain a singularity?
Technically, no black holes contain a singularity, as this would correlate only to theoretical, impossible, black holes with no rotation. The mass at the relative centre of the black hole would be spread out into a toroid (donut-like) shape, known as a ringularity. This ringularity will still take up zero space in the three dimensions, simultaneously being a ring of mass and a 1-dimensional point. It's very complicated at this level, and some even theorize that the solution to the black hole information paradox##### is that all matter is trapped at the edge of the event horizon, pressed completely flat in 2D form across the 3D bubble. (Explained in the ¶¶¶ link)
5. Does sound travel faster in space?
Sound is incapable of travelling in space. Sound requires atoms to travel through, as it's essentially a pressure wave. It may not seem like it, but our own atmosphere is a very thick soup of atoms, while space usually has an average of only 10 or so atoms per every square foot. However, it's a perfect medium for light to travel through relatively unhindered, which is why radio (light underneath our visual spectrum, below infrared) and microwave (light above our visible spectrum, above ultraviolet, but not as high as gamma) are ideal forms of communication in space.
6. Does the influence of gravity extend out forever?
Yep! You are affected by an atom on the edge of the universe, and vice versa - the influence of gravity just becomes weaker the further out other objects with mass are, and objects with more mass have stronger gravitational effects than objects with less mass, resulting in objects with less mass being influenced by objects with larger mass. This is why we're plastered to the surface of the Earth, which orbits Sol while Luna (Earth's Moon) orbits Earth, while Sol, alongside all other celestial objects in the Milky Way, orbit Sagittarius A* (not a link, the asterisk is part of the supermassive black hole's name), and so on and so forth with areas of increasing mass ad infinitum.
7. Galaxies look stationary, so why do scientists say they rotate?
The movement of the universe is limited by an integral factor: the speed of light. This is why larger organisms tend to move slower relative to smaller organisms. Mass can only travel so quickly. Consequently, despite galaxies rotating extremely fast (for instance, the Milky Way orbits at 130 miles per second in our stellar neighborhood, slower closer to Sagittarius A*, and faster further out near the ends of the galaxy's arms due to how torque works - TLDR, the further out something is from a moving object, the faster it will move until it reaches its relative speed barrier), we're unable to perceive their rotation easily due to how slowly they rotate in comparison to their size.
* A Wikipedia Article on Quantum Physics
** A Wikipedia Article on Quantum Superposition
*** A Wikipedia Article on Photons
**** A Wikipedia Article on Wave-Particle Duality
***** A Wikipedia Article on the Double-Slit Experiment
† A Wikipedia Article on General Relativity
†† A Wikipedia Article on the Schwarzschild Radius
††† A Wikipedia Article on the Schwarzschild Solution to Black Holes
†††† A Wikipedia Article on Eddington-Finkelstein Coordinates
††††† A Wikipedia Article on Special Relativity
‡ A Wikipedia Article on the Proposed Tolman-Oppenheimer-Volkoff Limit
‡‡ A Wikipedia Article on Black Holes (you will find many of the aforementioned links here)
‡‡‡ A Wikipedia Article on the Reissner-Nordström Solution to Black Holes
‡‡‡‡ A Wikipedia Article on the Gödel Solution to Black Holes
‡‡‡‡‡ A Wikipedia Article on the Kerr Solution to Black Holes
§ A Wikipedia Article on the Kerr-Newman Solution to Black Holes
§§ A Wikipedia Article on the Kasner Solution to Black Holes
§§§ A Wikipedia Article on the Lemaître–Tolman Solution to Black Holes
§§§§ A Wikipedia Article on the Taub-NUT Solution to Black Holes
§§§§§ A Wikipedia Article on the Milne Solution to Black Holes
‖ A Wikipedia Article on the FLRW Solution to Black Holes
‖‖ A Wikipedia Article on the pp-wave Solution to Black Holes
‖‖‖ A Wikipedia Article on the van Stockum dust Solution to Black Holes
‖‖‖‖ A Wikipedia Article on the Weyl–Lewis–Papapetrou Solution to Black Holes
¶ Kurzgesagt's First Video on Black Holes from 7 Years Ago, Regarding Miniature Black Holes
¶¶ Kurzgesagt's First Black Hole Explanation Video from 6 Years Ago
¶¶¶ Kurzgesagt's Second Black Hole Explanation Video from 5 Years Ago
¶¶¶¶ Kurzgesagt's Video on Black Hole Bombs
¶¶¶¶¶ A More Up-To-Date Kurzgesagt Video on Black Holes
# A Kurzgesagt Video on Known Large Black Holes (Size Comparison)
## A Wikipedia Article on Brown Dwarfs
### A Kurzgesagt Video on Universal Size Comparisons (Includes Brown Dwarfs)
#### A Wikipedia Article on Deuterium
##### A Wikipedia Article on the Black Hole Information Paradox
2
idk man it sound too complicated for an idiot like myself
i love space but idk much about it
one of life’s great mysteries
(i like kurzgesgat tho so that should help)
i’ll let the great geniuses of this website figure it out whilst i wish minecraft had a space and play it
i love space but idk much about it
one of life’s great mysteries
(i like kurzgesgat tho so that should help)
i’ll let the great geniuses of this website figure it out whilst i wish minecraft had a space and play it
2
I believe that answers in such vague theories are never simple. In my opinion its a combination of many factors that all play a role in us not having a clue if anything exists. Here are my thoughts:
About the 3 most known theories on the Fermi Paradox, here is my take on them:
This post seemed kinda random on this site, but it is called Planet Minecraft afterall...
- First of all, of course advanced life is extremely rare. As others have pointed out, there are many factors that have helped us become what we have become. There needs to be an available source of energy, the right temperatures, possibly a magnetic field, tides and more. Of course its not impossible for a race to survive without thumbs, or without Carbon and Oxygen, but the only advanced life we know so far requires such features.
- Let's consider this for a second. Even if Earth is incredibly and utterly rare, with a propability of 0.003% of a planet like that to exist, the universe is V A S T. In the infinitness of space, 0.003% is nothing. The same argument can also explain the fact that we haven't been contacted yet for the plain reason that they could be hundreds of light years away.
- Next thing to talk about is time. The fourth dimension, like the first three, is unfathomably large. Our minds cannot comprehend the vastness of spacetime. To put time into prespective, lets look at some numbers. Universe created 13.8 billlion years ago. Until 11 billion years ago, life was unstable. Like OP has said, the Milky Way could have been 700 times colonised by now? Some of these civilizations could have existed for millions of years. Wanna know how old our civilisation is? 6000 years old! 6000 years is a fraction of a fraction of their time. Their perception of time might be completely different. Even if they have discoved us during that time, they might have simply not reacted yet.
- Even if they do exist, how could they discover us? Alliens wouldn't just pull up to our planet and check if we have build anything? They would check from far away, on changes in the light of our Sun, in case we have built some structure that could be obstructing their view of it, or they could catch one of our million radio signals we have been throwing at space for the last 100 years. This means that only civilizations 100 light years away from us would have recieved said signals by now.(EDIT: there are other ways to assume that an advanced civilization exists, but they all work similar to these 2)
- Thing is, this goes both ways. We might haven't been discoved yet... but we haven't had any luck catching any signals. Why could this be happening? A possible explanation could be that currently alliens are not emitting any radio signals.
About the 3 most known theories on the Fermi Paradox, here is my take on them:
- The Great Filter is the depressing answer, because it indicates the end of humanity, but on the other hand seems unlikely since we obviously do not have any experience on mass extinctions in advanced life as a species.
- The Zoo hypothesis is the optimistic answer, since it not only indicates that we are not alone in the universe but also that these alliens respect boundaries and treat us as something that should not be disturbed, yet.
- The Rare Earth theory sounds the most ignotant to me. I have never been one to distinguish my self as unique compared to the rest of humanity, so as expected I would feel for our civilization as a whole.
This post seemed kinda random on this site, but it is called Planet Minecraft afterall...
2
Steve boi popping off
3
As someone who plays around with speculative biology and astrophysics in my free time, and the fact that pretty much every single simulation we run suggests that life of all forms, both as we know it and as we don't know it, should be popping up legiterally everywhere, yet in all the time we've searched and all the regions we've searched, while only being such a tiny percentage of the night sky in which we should've statistically found at least one sign of extraterrestrial life, the Great Filter* hypothesis is probably the most likely.
The statistics and simulations implying life should appear everywhere, (although biased, as we only have a sample size of one [Earth] to compare to), versus the raw data showing literally nothing but false leads and dead ends, implies that there is a Great Filter in which it's most likely the formation of life itself.
The formation of life has such a profound effect on its planet that even just a few thousand years of single-celled plankton, (lifeforms that are incapable of motility and are simply carried along in the wavelengths of the medium they're in, best understood on Earth in water, although could potentially also exist in upwinds in gas giants, brown dwarves, and other cool celestial bodies), it would have extremely noticeable effects on the atmosphere that would be visible from lightyears away, such as the combined presence of oxygen and methane, which do not occur together naturally.
Considering the conditions and age of the universe, life would've been most commonly concentrated around the time that dinosaurs were still roaming the Earth, but we have found zero evidence suggesting even so much as a Type 1 civilization on the Kardashev Scale**, or even anything close to where we are (approximately 0.75 on the Kardashev Scale), as it would be very noticeable both on an atmospheric composition scale and an engineering scale.
Any civilizations Type 2+ would have been pretty much immediately noticeable from the moment the SETI (the Search for Extra-Terrestrial Intelligence) Institute began searching the night sky, so the Dark Forest Hypothesis*** is completely unfeasible - we would've noticed profound effects on the night sky from their energy use requirements affecting their surroundings, not to mention any civilization capable of travelling near lightspeed would leave massive ionized gas trails behind them that would be easily detectable with modern technology.
While other forms of carbon-based life can form using XNA**** (Xenonucleic acid, an RNA/DNA alternative that uses a different sugar backbone than ribose), and silicon-based life can technically form (but would freeze into solid rock on contact with oxygen; most likely these would be chemosynthetic***** stromatolites✝), and even stranger boron-based life✝✝ that breathes methane, among pretty much anything that can make stable four-way bonds and form sugars, these would all still have very noticeable changes that we'd be able to see from Earth.
If you would like to see some examples on how extra-terrestrial life might form, may I suggest:
- Melodysheep - LIFE BEYOND: Chapter 1
- Melodysheep - LIFE BEYOND: Chapter 2
- Melodysheep - LIFE BEYOND: Chapter 3
- Biblaridion's Ongoing "Alien Biospheres" Series
- Katifeia, The Shrouded Waterworld (Prologue)
- PesterJest's Agrona in The Mania System (Content Warning for predator/prey relationships, animated gore, and alien animal violence)
- The Isla Project
- The Mystery Flesh Pit National Park Archive Website (While this is a fictional analogue horror and worldbuilding project, the Permian Basin Superorganism and its wildlife are a form of speculative biology)
- Panoptes V's Colors of Alien Skies (How alien skies would look)
- Panoptes V's Colors of Alien Worlds (How alien plants would look, although this is slightly biased as it's using the Sunscreen model, which mimics Earth in which plants reflect the most intense wavelengths of light rather than absorbing them, which in our case has resulted in green plants being the dominant colour)
* A Kurzgesagt Video on The Great Filter Hypothesis
** A Kurzgesagt Video on the Kardashev Scale
*** A Kurzgesagt Video on the Dark Forest Hypothesis
**** A Wikipedia Article on Xenonucleic Acids
***** A Wikipedia Article on Chemosynthesis
✝ A Wikipedia Article on Stromatolites
✝✝ A Worldbuilding StackExchange Forum on Boron-Based Life
Edit: Why does PlanetMinecraft change the formatting after you post something so you have to go back and fix the formatting? It's very annoying. /ot
The statistics and simulations implying life should appear everywhere, (although biased, as we only have a sample size of one [Earth] to compare to), versus the raw data showing literally nothing but false leads and dead ends, implies that there is a Great Filter in which it's most likely the formation of life itself.
The formation of life has such a profound effect on its planet that even just a few thousand years of single-celled plankton, (lifeforms that are incapable of motility and are simply carried along in the wavelengths of the medium they're in, best understood on Earth in water, although could potentially also exist in upwinds in gas giants, brown dwarves, and other cool celestial bodies), it would have extremely noticeable effects on the atmosphere that would be visible from lightyears away, such as the combined presence of oxygen and methane, which do not occur together naturally.
Considering the conditions and age of the universe, life would've been most commonly concentrated around the time that dinosaurs were still roaming the Earth, but we have found zero evidence suggesting even so much as a Type 1 civilization on the Kardashev Scale**, or even anything close to where we are (approximately 0.75 on the Kardashev Scale), as it would be very noticeable both on an atmospheric composition scale and an engineering scale.
Any civilizations Type 2+ would have been pretty much immediately noticeable from the moment the SETI (the Search for Extra-Terrestrial Intelligence) Institute began searching the night sky, so the Dark Forest Hypothesis*** is completely unfeasible - we would've noticed profound effects on the night sky from their energy use requirements affecting their surroundings, not to mention any civilization capable of travelling near lightspeed would leave massive ionized gas trails behind them that would be easily detectable with modern technology.
While other forms of carbon-based life can form using XNA**** (Xenonucleic acid, an RNA/DNA alternative that uses a different sugar backbone than ribose), and silicon-based life can technically form (but would freeze into solid rock on contact with oxygen; most likely these would be chemosynthetic***** stromatolites✝), and even stranger boron-based life✝✝ that breathes methane, among pretty much anything that can make stable four-way bonds and form sugars, these would all still have very noticeable changes that we'd be able to see from Earth.
If you would like to see some examples on how extra-terrestrial life might form, may I suggest:
- Melodysheep - LIFE BEYOND: Chapter 1
- Melodysheep - LIFE BEYOND: Chapter 2
- Melodysheep - LIFE BEYOND: Chapter 3
- Biblaridion's Ongoing "Alien Biospheres" Series
- Katifeia, The Shrouded Waterworld (Prologue)
- PesterJest's Agrona in The Mania System (Content Warning for predator/prey relationships, animated gore, and alien animal violence)
- The Isla Project
- The Mystery Flesh Pit National Park Archive Website (While this is a fictional analogue horror and worldbuilding project, the Permian Basin Superorganism and its wildlife are a form of speculative biology)
- Panoptes V's Colors of Alien Skies (How alien skies would look)
- Panoptes V's Colors of Alien Worlds (How alien plants would look, although this is slightly biased as it's using the Sunscreen model, which mimics Earth in which plants reflect the most intense wavelengths of light rather than absorbing them, which in our case has resulted in green plants being the dominant colour)
* A Kurzgesagt Video on The Great Filter Hypothesis
** A Kurzgesagt Video on the Kardashev Scale
*** A Kurzgesagt Video on the Dark Forest Hypothesis
**** A Wikipedia Article on Xenonucleic Acids
***** A Wikipedia Article on Chemosynthesis
✝ A Wikipedia Article on Stromatolites
✝✝ A Worldbuilding StackExchange Forum on Boron-Based Life
Edit: Why does PlanetMinecraft change the formatting after you post something so you have to go back and fix the formatting? It's very annoying. /ot
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Also, in case anyone's curious on my personal work of speculative biology, this is my speculative biology project's master document that I'll be updating regularly as changes occur (view permissions only).
Cobalt 111 B - Azure: The Planet of Blue (Master Document)
Cobalt 111 B - Azure: The Planet of Blue (Master Document)
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Oh man, thanks, you’ve given me something to do today, I watch melodysheep and kurzgesagt but I haven’t heard of anyone else, good thing I have nothing to do today
also, I heard that we actually did find a trail of ionized gas close to the center of the Milky Way, and people are saying we should get JWST to look at it
also, I heard that we actually did find a trail of ionized gas close to the center of the Milky Way, and people are saying we should get JWST to look at it
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kurzgesgat is a good content creator
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Oh, yes, my dear - Kurz is an excellent resource for vastly simplified scientific and political discussions that leave even those uneducated on the relevant topics feeling and being smarter by the end of it, and provide a plethora of sources in their descriptions for those curious to research themselves!
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I’ve watched this many times already
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nice
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The Great Filter makes a lot of sense. I think we would have already passed the great filter otherwise alien life would make themselves aware to us.
(if that’s how the great filter theory works…?)
(if that’s how the great filter theory works…?)
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So the age of the universe is about 14 billion years old. Our galaxy is 13 billion years old. Our solar system and planets formed 4.5 billion years ago. Now this doesn't take into account proto-galaxy discs that probably took a couple billion years to establish fullly and also proto-planetry discs. 13 - 4 is 9 so it could have very well taken 9 billion years for these things to become established
If you look at the age of the universe and the age of our galaxy.. we're practically at the beginning of the big bang. So wherever the big bang took place, we are nearby.. Andromeda Galaxy is estimated to be 10 billion years old. So Milky Way is actually older than Andromeda by three billion years and that is farther away from us, even though it is getting closer and due to collide in a few billion years
Life itself first began about 3.5 billion years ago. So that is one billion years after our Earth had formed and cooled enough to sustain environments for life to form and foster
What am I getting at? We are one of the first of a very small handful of civilizations in the galaxy. And possobly entire universe. There could be life elsewhere in the solar system or galaxy but its probably not as advanced as we are. Or its just about as advanced as we are. Given the time it took for everything to form and settle down most likely we all formed around the same timeframe
So I believe in the rare earth hypothesis. I believe there is life out there. I believe many non earth planets can harbor life but its restricted to things like fungus and algae. But when it comes to complex life like ourselves... its rare. Extremely rare. And that if there are other civlizations out there they are very far away from us. Sebastian von Hoerner who was an German astrophysicist hypothesized that alien civlizations were at least 1,000 light years apart. This being based on a caculation that one in three million stars in the milky way will have at least one planet capable of sustaining intelligent life
https://www.daviddarling.info/encyclopedia/H/Hoerner.html
There is also the Dark Forest theory I subscribe to which makes sense and paints us humans as idiots. But then I just wonder if the universe is a simulation and we're just glitches in the matrix :P
If you look at the age of the universe and the age of our galaxy.. we're practically at the beginning of the big bang. So wherever the big bang took place, we are nearby.. Andromeda Galaxy is estimated to be 10 billion years old. So Milky Way is actually older than Andromeda by three billion years and that is farther away from us, even though it is getting closer and due to collide in a few billion years
Life itself first began about 3.5 billion years ago. So that is one billion years after our Earth had formed and cooled enough to sustain environments for life to form and foster
What am I getting at? We are one of the first of a very small handful of civilizations in the galaxy. And possobly entire universe. There could be life elsewhere in the solar system or galaxy but its probably not as advanced as we are. Or its just about as advanced as we are. Given the time it took for everything to form and settle down most likely we all formed around the same timeframe
So I believe in the rare earth hypothesis. I believe there is life out there. I believe many non earth planets can harbor life but its restricted to things like fungus and algae. But when it comes to complex life like ourselves... its rare. Extremely rare. And that if there are other civlizations out there they are very far away from us. Sebastian von Hoerner who was an German astrophysicist hypothesized that alien civlizations were at least 1,000 light years apart. This being based on a caculation that one in three million stars in the milky way will have at least one planet capable of sustaining intelligent life
https://www.daviddarling.info/encyclopedia/H/Hoerner.html
There is also the Dark Forest theory I subscribe to which makes sense and paints us humans as idiots. But then I just wonder if the universe is a simulation and we're just glitches in the matrix :P
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I think being one of the first civilizations is reasonable, but I have to disagree about the rare earth hypothesis. I definitely think intelligent life is rare, and i also think that is evolving on earth helped us become intelligent and venture into space. Not much use making a space program if you’re living under a 100 kilometer thick ice sheet on a Europa-like world, if you were even able to use a fire replacement to make food and metals. But earth life probably isn’t the only type of life that can evolve intelligence. Scientists have predicted there’s thousands, if not millions of alternatives to DNA or RNA, and that’s not including silicon based life or other exotic forms. The universe allows life to exist in so many different ways. To quote Carl Sagan, “if it’s just us, it seems like an awful waste of space.”
I definitely think intelligence is rare. But I don’t think it’s impossibly rare.
I definitely think intelligence is rare. But I don’t think it’s impossibly rare.
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1) Earth is located in a region of the Galaxy (Orion's Arm) where alien activity is low.
2) Aliens, most likely, are different, some do not want to touch us, and some are fascists. We're probably just lucky. Maybe even some kind of "kind" civilization defended our "reserve" from the aggressive and warlike hordes, and we will never even know.
3) Also, maybe warp drive is not possible, and therefore aliens colonize territories extremely slowly, and given the average distance between planets with intelligent life, contact between civilizations is extremely unlikely.
2) Aliens, most likely, are different, some do not want to touch us, and some are fascists. We're probably just lucky. Maybe even some kind of "kind" civilization defended our "reserve" from the aggressive and warlike hordes, and we will never even know.
3) Also, maybe warp drive is not possible, and therefore aliens colonize territories extremely slowly, and given the average distance between planets with intelligent life, contact between civilizations is extremely unlikely.
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I don’t think distance is a big factor. To show this, lets assume that there’s an alien civilization that wants to colonize the entire galaxy. Say their spacecraft move at 50% the speed of light. The closest stellar neighbor to the Sun is Proxima Centauri, at a distance of 4.26 light years, so let’s assume on average stars are five light years apart. That means it takes ten years for an alien civilization to reach the next star and establish a presence. Now, the aliens have two stars, and those stars colonize two more, in ten years. In forty years, 16 stars. In 100 years, 1,024. This multiplied exponentially, until in a few million years the civilization has colonized the entire galaxy. Sure, this is a perfect scenario where nothing goes wrong, but we just need one civilization and a bit of luck and they control the entire Milky Way.
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1) Perhaps some systems simply skip, because. they are unprofitable. 2) The reserve may also take place, it may even be such that the earth is "besieged" by an alien civilization from all sides.
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The universe is too big and we’re going too far, i think its meant to be just us.
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So you believe the rare earth hypothesis? That’s the theory where earth is the only planet in the universe that supports life because it’s the only one that gets everything exactly right.
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Could be a combination of the fact that Earth is so rare and also the fact that the universe is extremely vast. Like, maybe there is another planet that happened to be able to support advanced life, but it is so far away, that even if they were 1000 years ahead of us, it would be unlikely that they wouldn't even bother making contact or even be able to make contact.
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Atmospheric conditions are weird man, idk what to tell ya
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Space and time is flexible/organic/homogeneous like a Strawberry milkshake with chocolate sprinkles and chatili frosting accompanied by a transparent straw and napkin with a print of smiling bears holding a jar of honey...
I don't think we should trust these numbers because the margin of error is the size of everything, this is the plot twist of science.
I don't think we should trust these numbers because the margin of error is the size of everything, this is the plot twist of science.
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Personally, I think evolving intelligence is so rare, we're either the first or one of the first to do it in the milky way. We had 4.5 billion years, and everything had to go absolutely right, just for our brains to get big. First, cyanobacteria had to evolve and flood the atmosphere with oxygen. Then, we had to become multicellular. Our ancestors had to survive every mass extinction event. The dinosaurs had to go extinct so mammals could take over. Then, Africa had to dry up so we had to walk instead of swing in trees. If even one of these events went differently, if the dino-killing asteroid hit just a hundred miles to the left, if all live went extinct during the Great Dying, we wouldn't be here. So, I think the Great Filter, a single event so hard to overcome it kills every civilization that faces it, is already behind us.
But I want to hear from you, so share your opinions in the comments!
But I want to hear from you, so share your opinions in the comments!
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Our brains are shrinking
omg y’all domesticated yourselves like cats
omg y’all domesticated yourselves like cats
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Realize that it takes a lot of intelligence and technological development to be able to do a tourist safari right here in our solar system, also realize that there are many minerals / resources / curiosities / studies right here in our solar system, mars / saturn /jupter(laughs) we will have enough technology to go further but without bothering the anthills or any minority biodiversity, because until today we adventures never need to touch/break randomly anthills because we adventures are ants of a minority biodiversity.
There is a popular saying that says "there are Doctors and there are Doctors, both are doctors but they don't do the same job". So I'm a mechanic but my neighbor is also a mechanic, we are mechanic but not make a same job. 🤨
I think me, you and Enrico Fermi lost track of time and space when making the measurements, I think we need more time and doctors for this to fix the car.
I think that human beings need to encourage more combined micro and macro thinking, this helps to expand knowledge chance to two sides.
I don't think I want to think about it anymore, I'm going to sit in my armchair and plan how I'm going to destroy anthills before they destroy me. 🤔
There is a popular saying that says "there are Doctors and there are Doctors, both are doctors but they don't do the same job". So I'm a mechanic but my neighbor is also a mechanic, we are mechanic but not make a same job. 🤨
I think me, you and Enrico Fermi lost track of time and space when making the measurements, I think we need more time and doctors for this to fix the car.
I think that human beings need to encourage more combined micro and macro thinking, this helps to expand knowledge chance to two sides.
I don't think I want to think about it anymore, I'm going to sit in my armchair and plan how I'm going to destroy anthills before they destroy me. 🤔
