Aliens..

[3blake7]

There could be aliens on Earth. If a species a million years older than us, discovered immortality and embraced exponential population growth, they would have traveled to every star system in the galaxy by now. They may have us completely surrounded, at every neighboring star system.They could have terraformed hundreds of billions of worlds. They could have watched as planets with life, less developed, matured, achieved sentient and eventually global consciousness. They could be manipulating us through immortal agents implanted on the planet. We could be a reality TV show for scientists of an alien race.

They could be on Earth, possibly found or there may be detectable evidence, in the form of sunshades around planets too close to their stars.

[Roamer]

 

 

We could be a reality TV show for scientists of an alien race.

 

I think there was a South Park episode about that.

[3blake7]

I'm serious! With particle accelerator thrusters, they'd only need like half an empire state building worth of propellant, be able to do a constant acceleration of 0.5 m/s^2 and do like 10 lightyears in 30 years. They could take the whole galaxy in a million years!

[swansont]

 

discovered immortality

 

That's not a trivial assumption

[Phi for All]

 

That's not a trivial assumption

 

But it also doesn't need to be a requirement. Multi-generational ships could take the place of immortals.

 

I think the real trivial assumption is that the aliens in the OP are able to completely mask themselves from detection. If they had colonized everywhere, why can't we see some indication? Perhaps we're being manipulated to miss all those energy signatures.

 

Any species that could pull this off would need to be a Type II Civilization at least. They'd need to be able to efficiently use the energy output of their home star. That's going to leave a mark.

[swansont]

 

But it also doesn't need to be a requirement. Multi-generational ships could take the place of immortals.

 

 

Also not a trivial assumption, considering that nothing close to a multi-generation ship has been successfully demonstrated on anything smaller than a solar system.

[Phi for All]

They could be manipulating us through immortal agents implanted on the planet.

 

Be careful with this kind of argument. You're purposely setting up a highly improbable situation, and then assuming it already exists but somehow can't be observed. Science needs to be able to falsify an hypothesis in order for it to be considered. If there's nothing to support this idea, how can we look at it scientifically?

 

 

Also not a trivial assumption, considering that nothing close to a multi-generation ship has been successfully demonstrated on anything smaller than a solar system.

 

Very true. And I don't know why I assume the ship technology is more plausible than immortality, but I guess I do. I'm not a big fan of immortality, omnipotence, infinity, or any of those unlimited propositions.

[3blake7]

I made a post about immortality on the Medicine forum. An expert there was so kind to expand upon what I was able to research. Immortality does not seem to be a stretch at all. It seems based on their current level of understanding of the problem and the rate of advancement we could have it optimistically in 30 years. If somehow we don't figure it out, based on projections of computer processing advancements by Ray Kurzweil, we would have supercomputers more than capable of simulating genetics, cellular mitosis and their emergent properties which would allow us to come to a complete understanding of the biological processes. There is also Molecular Manufacturing and Nanotechnology. Researchers have already created nanomotors smaller than the size of a cell, while basic, we are making great leaps in the field of nanotechnology. Some predictions are that we could have a Molecular Manufacturer, the ability to mass produce any design of a nanomachine, optimistically, within 30 years. To be conservative, 100 years is very, very likely.

 

As far as relativistic speed and time dilation on interstellar travel, I was able to come up with an idea that would make an alien race capable of expanding throughout the entire galaxy within 1 million years. That idea was to use particle accelerators as thrusters. The LHC can accelerator particles up to 99% of the speed of light and if we had a thruster with an exhaust velocity 99% of the speed of light we could be capable of 0.5-1.0 m/s^2 of constant acceleration. The high exhaust velocity also reduces the mass of the propellant required. I did a basic calculation and you would only need an empire state building sized tank to do 0.5 m/s^2 and travel 4.6 lightyears in around 18 years. That would take them 2 million years. 1.0 m/s^2 seems in the realm of possibility as well.

 

If they were immortal and had our population growth rate of 19 per 1000, we would have a population of 500 quadrillion by the year 3000.

 

Terraforming is also not a huge stretch when you think about trillions of people living in space throughout the star system. With self-replicating autonomous industries, such as a spacecraft that serves the function of a Surveyor, Excavator, Hauler, Loader, Feeder, Crusher, Separator, Smelter, Mold Caster, Part Caster, Grinder, Assembler and eventually Molecular Manufacturer. The first seven have already been made mobile, the rest, minus molecular manufacturing already exist in the industry but not as mobile machines. With an industry that could grow exponentially through self-replication, we could scale an industry that mines, refines, smelts and casts steel parts within as little as 22 years. Then it would only take another 100 years to manufacture enough steel parts to build a sunshade, a spacescraper and 340 million 20 gigaliter supertankers. Then we use those things to move around gases to create Earth-like atmosphere on Venus and Mars. We can also use the Haber process to make Urea to fertilize the planets and use the Scheibersite from the M-Type asteroids to further fertilize. We could do all this by the year 2600 and this approach is much more pragmatic than other terraforming approaches.

 

As far as not being able to detect them. I would assume they have a complete understanding of genetics and could easily achieve any outcome they wish with genetic engineering. They would also probably have the capability using nanomachines to alter the genetics of fully grown beings without negative side effects. With their level of nanotechnology they could easily have visual spectrum cloaks. They could have also been here long before we developed technology and would be able to access our ability to detect them long before we started looking or chanced upon them. They could also have withdrew anything we may detect as we developed the ability to detect them. As far as communications go, they may use lasers as direct line-of-sight communication instead of the more costly EM fields which radiate out in all directions.

 

I think the most detectable thing would be sunshades.

Edited July 3, 2015 by 3blake7

[The Architect]

I would like to reply to your question/assumption that first of all stop watching too many sifi sitcoms and documentry and think for a second that after the big bang what is the posibility that we could be the most intelligent species in this universe what if our own thoughts about exploring the depts and secrets of universe lead us to being more intelligent than our ancistors. What if we are the aliens!!! and we are looking for nothing but finding a companion in this single multiverse.

[Moontanman]

Multi generational ships would not have to be completely self contained and only short hops from one stars oort cloud to another need be made. I think it's doubtful aliens would be interested in planets, artificial colonies powered by fusion would be more likely. So the idea of aliens on the earth would also assume they look like us which is highly unlikely..

 

For a hop to other stars oort cloud you could use a long period comet, accelerate it enough so that it escapes the host star and ride along with it using it's mass to replace volatiles lost to space and the adjust for other losses in your colonies ecosystem. Decelerate your colony, but not the comet, when you get to the next stars oort cloud and start making more colonies, travel times might be hundreds or even thousands of years but you are not looking for anything other than raw materials, whether or not a star has a habitable planet is not part of the equation so nearly all stars are on the menu sotospeak....

 

Fusion is the biggest assumption and of course we'll have that in 20 years or so... for sure...

[StringJunky]

I would like to reply to your question/assumption that first of all stop watching too many sifi sitcoms and documentry and think for a second that after the big bang what is the posibility that we could be the most intelligent species in this universe what if our own thoughts about exploring the depts and secrets of universe lead us to being more intelligent than our ancistors. What if we are the aliens!!! and we are looking for nothing but finding a companion in this single multiverse.

I'm inclined to think this way; evolution can only move so fast.

[MonDie]

 

But it also doesn't need to be a requirement. Multi-generational ships could take the place of immortals.

Also not a trivial assumption, considering that nothing close to a multi-generation ship has been successfully demonstrated on anything smaller than a solar system.

 

How much propellant to fast-foward with special relativity?

Edited July 5, 2015 by MonDie

[swansont]

 

How much propellant to fast-foward with special relativity?

 

I don't understand the question. Are you asking how much propellant to reach relativistic speeds?

 

The classical equation is v_f = v_e ln(m₀/m₁) (v_e is exhaust speed, m₀ is starting mass, m₁ is the mass of the non-propellant part)

 

It gets modified somewhat for the relativistic case https://en.wikipedia.org/wiki/Relativistic_rocket#Relativistic_rocket_equation

 

Realistically, m₀ < 2m₁ because you have to slow down again at the end of the trip (which will be more efficient, but you also need propellant to maneuver) and the payload is not zero, so your speed is limited to something less than the exhaust speed of your propellant. i.e. if you want to go relativistic, you need a relativistic propellant, i.e a particle accelerator. Then there's the issue of how much thrust you can generate, because there's no point to this if it takes a thousand years just to get moving at a decent clip. How efficient this all is is a matter of how much dead weight you must carry to run the thruster (Ideally, anything that becomes garbage becomes propellant)

 

The closest we've come is ion thrusters, reaching 10 km/s (relativistic speeds are out there beyond 10,000 km/s)

https://en.wikipedia.org/wiki/Ion_thruster

[Moontanman]

 

I don't understand the question. Are you asking how much propellant to reach relativistic speeds?

 

The classical equation is v_f = v_e ln(m₀/m₁) (v_e is exhaust speed, m₀ is starting mass, m₁ is the mass of the non-propellant part)

 

It gets modified somewhat for the relativistic case https://en.wikipedia.org/wiki/Relativistic_rocket#Relativistic_rocket_equation

 

Realistically, m₀ < 2m₁ because you have to slow down again at the end of the trip (which will be more efficient, but you also need propellant to maneuver) and the payload is not zero, so your speed is limited to something less than the exhaust speed of your propellant. i.e. if you want to go relativistic, you need a relativistic propellant, i.e a particle accelerator. Then there's the issue of how much thrust you can generate, because there's no point to this if it takes a thousand years just to get moving at a decent clip. How efficient this all is is a matter of how much dead weight you must carry to run the thruster (Ideally, anything that becomes garbage becomes propellant)

 

The closest we've come is ion thrusters, reaching 10 km/s (relativistic speeds are out there beyond 10,000 km/s)

https://en.wikipedia.org/wiki/Ion_thruster

 

Ummm, speed is limited by the speed of the exhaust? You cannot exceed the speed of your exhaust particles? You sure about that? Continuous thrust even of relatively slow exhaust speeds should add up over time to allow the rocket to exceed its exhaust velocity.

[3blake7]

Eat spreadsheet: https://docs.google.com/spreadsheets/d/12VQXeNwbLyUAzzwgPj4Qman6c0pUwHcGeE51MLeg5fw/edit?usp=sharing

 

It uses a constant acceleration drive, which accelerates towards a star until the half-way point, then flips around and accelerates in the opposite direction the second half of the trip, to slow down just as it reaches the destination star. The propellant is Argon. The thruster is a particle accelerator and uses an exhaust velocity that the LHC is able to do. It uses a liquid fluoride thorium reactor. The weights might be a little off (hard to be exact without being an engineer and going into tons of detail) but you'll get the idea.

 

With the really high exhaust velocity, you reduce the propellant weight ALOT and make it scalable.

 

It has two donut-shaped habitats which rotate to create artificial gravity. They are 500000 people each. There should be enough room for self-sustaining hydroponics, they will just need to take with them big tanks of fertilizer. There IS NOT enough to recycle CO2, that's just ridiculous so some other means has to be used, like artificial scrubbers, possibly those bionic leaves that were recently invented.

I think the scariest thing is running into a piece of sand at 150,000 km/s

Edited July 5, 2015 by 3blake7

[MonDie]

 

Ummm, speed is limited by the speed of the exhaust? You cannot exceed the speed of your exhaust particles? You sure about that? Continuous thrust even of relatively slow exhaust speeds should add up over time to allow the rocket to exceed its exhaust velocity.

 

Exactly! That is, if it's the speed of the exhaust relative to the vehicle upon ejection / thrust.

If m₀ < 2m₁

then m₀/m₁ < 2

then ln(m₀/m₁) < 0.7 and v_f or Δv < 0.7v_e

It uses a constant acceleration drive, which accelerates towards a star until the half-way point, then flips around and accelerates in the opposite direction the second half of the trip, to slow down just as it reaches the destination star.

 

Then why is it using Δv? Δv would mean change in speed, but under your description, the ultimate value of Δv (v₂ - v₁) would only be the speed of that target planet relative to the home planet, not the max speed.

 

[snip]

Realistically, m₀ < 2m₁ because you have to slow down again at the end of the trip (which will be more efficient, but you also need propellant to maneuver) and the payload is not zero [/snip]

 

?????

Edited July 5, 2015 by MonDie

[swansont]

 

Ummm, speed is limited by the speed of the exhaust? You cannot exceed the speed of your exhaust particles? You sure about that? Continuous thrust even of relatively slow exhaust speeds should add up over time to allow the rocket to exceed its exhaust velocity.

 

You can exceed exhaust velocity if your payload mass is small enough. That's the result, though, under some assumptions I have detailed. You run out of fuel before you exceed the exhaust velocity.

 

Then why is it using Δv? Δv would mean change in speed, but under your description, the ultimate value of Δv (v₂ - v₁) would only be the speed of that target planet relative to the home planet, not the max speed.

 

Because you might not start at rest

 

–––––

 

A ship that is traveling to some distant planet has to slow down when it reaches its destination. You have to save some fuel for that, and also for maneuvering, which will limit your top speed. I assumed half of the fuel, as a rough estimate.

[Harold Squared]

 

But it also doesn't need to be a requirement. Multi-generational ships could take the place of immortals.

 

I think the real trivial assumption is that the aliens in the OP are able to completely mask themselves from detection. If they had colonized everywhere, why can't we see some indication? Perhaps we're being manipulated to miss all those energy signatures.

 

Any species that could pull this off would need to be a Type II Civilization at least. They'd need to be able to efficiently use the energy output of their home star. That's going to leave a mark.

It will most certainly, as will slowing down from relativistic velocity. Edited July 8, 2015 by Harold Squared

[Gorototh]

Okay, I still don't understand why it's necessary to hold these absurd beliefs in something greater than ourselves. I really encourage the OP to get into scientific research and literacy. I think the OP has overthought this and is overwhelmed mentally, incapable of coming out of his own delusion. I strongly recommend to get a more precise understanding of the world you live in and how the natural world works.

Unless of course we are talking of science fiction which is obviously awesome. In that case yes. Aliens.

[3blake7]

Okay, I still don't understand why it's necessary to hold these absurd beliefs in something greater than ourselves. I really encourage the OP to get into scientific research and literacy. I think the OP has overthought this and is overwhelmed mentally, incapable of coming out of his own delusion. I strongly recommend to get a more precise understanding of the world you live in and how the natural world works.

 

Unless of course we are talking of science fiction which is obviously awesome. In that case yes. Aliens.

 

Why the personal insults? This is The Lounge afterall. Also, what's so ridiculous about aliens having occupied the entire galaxy already? What research have YOU done? Scientists haven't been able to create a model of star system formation that is 100% accurate and precise so they can't say with certainty how many Earth-like planets exist in our galaxy. Some put the estimate as high as 1 million while others put the estimate as low as 1 thousand. We know Life began to evolve on Earth 3.4 billion years ago. It took THAT long for the components of a cell, plant or animal, to evolve into a self-contained system and then into multi-cellular systems. Neanderthals have existed for 400 thousand years and scientists actually obtained Neanderthal DNA and did a genetic comparison to the modern homo-sapiens and determined that they are technically homo-sapien too. Dinosaurs exists 100s of millions of years ago. In the grand scheme of things it, intelligent life evolving on a planets is a blip in the radar of evolution. Most of the time was spent just getting the building blocks of life right. It is not unreasonable to assume that if there is another intelligent species in the galaxy that they could have evolved, lets say 8 million years before us. With immotality, which scientists are predicting we will have within the next 30-60 years and can already be done to a degree with the telomerase enzyme, and exponential population growth. An alien civilization, with a 8 million year head start, could have quadrillions in every star system. As far as space propulsion goes, we already have existing technology, like the Large Hadron Collider, which is capable of accelerating particles to 99.9% the speed of light. With a thruster, with an exhaust velocity 99% the speed of light and a tank about 10 times the size of the Empire State Building, they could reach a nearby star in as little as 32 years (4 lightyears). They could have expanded to every star within 8 million years. They would mostly live in space, on space stations and mine asteroid belts for raw materials to build more space stations to support their exponentially growing population. They would terraform worlds too, but only a small percentage of their population would live on planets.

 

This is plausible and I think most people have just been stigmatized.

 

I think the real trivial assumption is that the aliens in the OP are able to completely mask themselves from detection. If they had colonized everywhere, why can't we see some indication? Perhaps we're being manipulated to miss all those energy signatures.

 

With a 8 million year head start (I switched the thruster to 10kg/s at 99.9% exhaust velocity, a little more conservative), they could have nanotechnology capable of visual spectrum cloaking. We are already able to cloak objects in a single frequency. They would also have very advance nanomachines, capable of altering their appearance or just create a modified version of their own genome with a human-like appearance. There are a lot of plausible explanations even when you consider our current level of technology and what is currently being developed in universities around the world.

 

I don't think it would be that difficult to go undetected. About the only thing we can detect in other star systems is the dimming of a star when a planetary body passes in front of it. Even so, we can only detect very large planetary bodies, such as three times the mass of Earth. Within our own star system, we still have a lot of blind spots. We have asteroids and comets we don't even know about. We have a dismal awareness of our own star system. Aliens could have come and gone, and we would have never noticed, even if they did so within the last 100 years.

 

https://docs.google.com/spreadsheets/d/12VQXeNwbLyUAzzwgPj4Qman6c0pUwHcGeE51MLeg5fw/edit?usp=sharing

Edited July 16, 2015 by 3blake7

[ACG52]

They might be invisible pink unicorns. That could be why we don't see them.

[3blake7]

Hollywood hinders scientific progress more often than not.

[Unity+]

Okay, I still don't understand why it's necessary to hold these absurd beliefs in something greater than ourselves. I really encourage the OP to get into scientific research and literacy. I think the OP has overthought this and is overwhelmed mentally, incapable of coming out of his own delusion. I strongly recommend to get a more precise understanding of the world you live in and how the natural world works.

 

Unless of course we are talking of science fiction which is obviously awesome. In that case yes. Aliens.

I don't see it as absurd, more stretched though.

 

I think the implications of aliens on Earth would leave many questions: Why are they even interested in us? If they are far more technologically evolved, what interest would they have in us? We tend to leave other species alone except for pets and maybe even research, but I think there is a consistency with how higher lifeforms treat lower lifeforms.

 

It isn't impossible, but until there is actually evidence, all we can do is speculate, which isn't bad. However, speculations just leave "What ifs", which many feel uncomfortable with.

They might be invisible pink unicorns. That could be why we don't see them.

But I don't think we are discussing unicorns.

Edited July 16, 2015 by Unity+

[3blake7]

I don't see it as absurd, more stretched though.

 

I think the implications of aliens on Earth would leave many questions: Why are they even interested in us? If they are far more technologically evolved, what interest would they have in us? We tend to leave other species alone except for pets and maybe even research, but I think there is a consistency with how higher lifeforms treat lower lifeforms.

 

It isn't impossible, but until there is actually evidence, all we can do is speculate, which isn't bad. However, speculations just leave "What ifs", which many feel uncomfortable with.

But I don't think we are discussing unicorns.

 

In this speculative but plausible scenario, the aliens may have stumbled upon this planet and just have decided to allow us to develop. They would watch us out of curiosity, to study the evolution of civilization, perhaps even as a form of entertainment. They may also manipulate us to a degree to ensure that we develop into a compatible civilization. The planet itself would not have much value to an intelligent species that mostly lives in space, mines asteroid belts and can terraform worlds.

[Unity+]

 

In this speculative but plausible scenario, the aliens may have stumbled upon this planet and just have decided to allow us to develop. They would watch us out of curiosity, to study the evolution of civilization, perhaps even as a form of entertainment. They may also manipulate us to a degree to ensure that we develop into a compatible civilization. The planet itself would not have much value to an intelligent species that mostly lives in space, mines asteroid belts and can terraform worlds.

In the seriousness of things, I did have a shower thought that considered that maybe aliens don't want to reveal themselves yet because they want to wait till we are ready to join a "galactic union" because of how f'd up we are at the moment. Question is if we will ever be ready for such a state of humanity. Though, whether this speculation is to be taken seriously is up to you guys.

 

I think the question of aliens really brings up a philosophical point of how we self-reflect on humanity. I remember Reagan stating how we would need an alien species to help unite us, whether it be from hostility or, even peace.

 

Maybe the idea of an intelligent, alien species is the creation of a society to help us observe ourselves more closely and how we interact from our prejudices, violence, and policy.

Edited July 16, 2015 by Unity+