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Post Reply NASA reveals new habitable planets outside our solar system
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Posted 2/23/17 , edited 2/23/17

nanikore2 wrote:

Aside from those, it'd be a whole lot faster just to build a bunch of large space colonies around our solar system's Lagrange points.



I never thought of that.


Ryulightorb wrote:

If anything we could use the sun as the needed boost of power to send us to another star system.


This doesn't make any sense. What you are proposing is essentially eating the sun: not only do we not possess anything with the capability of storing anything close to that much energy; we have no way of extracting the energy in a useful form. The sun does contain an absurd amount of energy, but if we're talking propelling an aircraft carrier to half the speed of light, I think the sun puts out more than enough energy to do that every second (if my naive relativistic total energy - rest mass energy calculation is correct). So eating the sun would be overkill.

Now, if we wanted to travel via propagating warp bubble, you probably would have to eat the sun to do that. Last I heard the amount of energy necessary for that is the rest energy of Jupiter - which is how much energy the sun puts out in, oh, only 30 billion years.
Posted 2/23/17

Ryulightorb wrote:


TartanButterfly wrote:

Well of course i don't particularly want to die but i wouldn't want to live forever either, especially if that meant going to space.


Someone sounds scared >.> why not live forever ?


The idea of me living forever and having to deal with other people forever just sounds incredibly unappealing, also what if i went to space and moved to another planet and i had to coexist with an alien race?? That just means i have an entirely new race of beings on top of the human race to deal with on a regular basis for all eternity, it just sounds exhausting!!!
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Posted 2/23/17

TartanButterfly wrote:


Ryulightorb wrote:


TartanButterfly wrote:

Well of course i don't particularly want to die but i wouldn't want to live forever either, especially if that meant going to space.


Someone sounds scared >.> why not live forever ?


The idea of me living forever and having to deal with other people forever just sounds incredibly unappealing, also what if i went to space and moved to another planet and i had to coexist with an alien race?? That just means i have an entirely new race of beings on top of the human race to deal with on a regular basis for all eternity, it just sounds exhausting!!!


But if you have someone you love with you isn't it better of an idea ?
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Posted 2/23/17

auroraloose wrote:


nanikore2 wrote:

Aside from those, it'd be a whole lot faster just to build a bunch of large space colonies around our solar system's Lagrange points.



I never thought of that.


Ryulightorb wrote:

If anything we could use the sun as the needed boost of power to send us to another star system.


This doesn't make any sense. What you are proposing is essentially eating the sun: not only do we not possess anything with the capability of storing anything close to that much energy; we have no way of extracting the energy in a useful form. The sun does contain an absurd amount of energy, but if we're talking propelling an aircraft carrier to half the speed of light, I think the sun puts out more than enough energy to do that every second (if my naive relativistic total energy - rest mass energy calculation is correct). So eating the sun would be overkill.

Now, if we wanted to travel via propagating warp bubble, you probably would have to eat the sun to do that. Last I heard the amount of energy necessary for that is the rest energy of Jupiter - which is how much energy the sun puts out in, oh, only 30 billion years.



If we have the capability to make a dyson sphere we would have the capability to store and use.
Eating it would be overkill i guess but using it to escape as a last resort would be possible if we attain that level of technology.

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Posted 2/23/17

Ryulightorb wrote:


auroraloose wrote:


Ryulightorb wrote:

If anything we could use the sun as the needed boost of power to send us to another star system.


This doesn't make any sense. What you are proposing is essentially eating the sun: not only do we not possess anything with the capability of storing anything close to that much energy; we have no way of extracting the energy in a useful form. The sun does contain an absurd amount of energy, but if we're talking propelling an aircraft carrier to half the speed of light, I think the sun puts out more than enough energy to do that every second (if my naive relativistic total energy - rest mass energy calculation is correct). So eating the sun would be overkill.

Now, if we wanted to travel via propagating warp bubble, you probably would have to eat the sun to do that. Last I heard the amount of energy necessary for that is the rest energy of Jupiter - which is how much energy the sun puts out in, oh, only 30 billion years.



If we have the capability to make a dyson sphere we would have the capability to store and use.
Eating it would be overkill i guess but using it to escape as a last resort would be possible if we attain that level of technology.



Dyson spheres are impossible and absurd. The gravitational field inside a uniform shell is exactly zero, so that (i) you wouldn't be able to stand on the inner surface, and (ii) the shell would have nothing to keep it centered on the star. Giant interconnected units could form a net or ring, though.

Second, this energy we store would most likely have to come along on the ship (unless it's propelled by light pressure from lasers on earth or some other object in the solar system). The outermost layers of the sun aren't all that dense, so I'm not sure what it is you want to do with the sun. And if all you mean is that we can use the sun to collect energy, we already do that. If we were to send a ship to another star, we'd have to convert the energy we have into ship/engine/fuel form (again, unless we're propelling it by shooting lasers at it). So it's too simplistic to call this a "boost of power" from the sun.

I think you have an exaggerated view of scientific possibility. Hoping for breakthroughs is fine, but unless you're an expert your ideas as to how they'd work are probably wrong.
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Posted 2/23/17
That's why this is the worst time period to live in 150 years to late to explore the earth and 150 years to early to explore space
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Posted 2/23/17 , edited 2/24/17

auroraloose wrote:

Dyson spheres are impossible and absurd. The gravitational field inside a uniform shell is exactly zero, so that (i) you wouldn't be able to stand on the inner surface, and (ii) the shell would have nothing to keep it centered on the star. Giant interconnected units could form a net or ring, though.

Second, this energy we store would most likely have to come along on the ship (unless it's propelled by light pressure from lasers on earth or some other object in the solar system). The outermost layers of the sun aren't all that dense, so I'm not sure what it is you want to do with the sun. And if all you mean is that we can use the sun to collect energy, we already do that. If we were to send a ship to another star, we'd have to convert the energy we have into ship/engine/fuel form (again, unless we're propelling it by shooting lasers at it). So it's too simplistic to call this a "boost of power" from the sun.

I think you have an exaggerated view of scientific possibility. Hoping for breakthroughs is fine, but unless you're an expert your ideas as to how they'd work are probably wrong.



They are absurd yes but the idea itself is what matters not how we think one would work now.

The idea of capturing the energy of the sun and harnessing it on an enermous scale is what i'm on about impossible dyson sphere or another way.

Yes i never said it wouldn't come with the ship obviously if you are storing energy its better to bring it with you.

My view of scientific possibility isn't exaggerated but you can feel free to think so i know Dyson spheres are a pipe dream but for a theoretical for something like that it still works.
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Posted 2/23/17

Ryulightorb wrote:

They are absurd yes but the idea itself is what matters not how we think one would work now.

The idea of capturing the energy of the sun and harnessing it on an enermous scale is what i'm on about impossible dyson sphere or another way.

Yes i never said it wouldn't come with the ship obviously if you are storing energy its better to bring it with you.

My view of scientific possibility isn't exaggerated but you can feel free to think so i know Dyson spheres are a pipe dream but for a theoretical for something like that it still works.


What you just said does not make very much sense.

I am a theoretical physicist, and I am telling you right now that we physicists and engineers already know that Dyson spheres are a terrible idea: a Dyson sphere possesses no internal gravitational field and thus could easily drift into the sun. No magical idea or theory anyone might possibly think up in the future will change that. So no, it does not work. I could imagine all sorts of scenarios - a shrink ray, for example - but that doesn't mean they're possible. (Shrink rays are impossible, by the way.) Thinking about such things might be fun and interesting, and they might even lead to new ideas - Einstein famously imagined what it'd be like to run alongside a beam of light at the speed of light - but none of that makes them any less impossible.
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Posted 2/23/17

auroraloose wrote:


Ryulightorb wrote:

They are absurd yes but the idea itself is what matters not how we think one would work now.

The idea of capturing the energy of the sun and harnessing it on an enermous scale is what i'm on about impossible dyson sphere or another way.

Yes i never said it wouldn't come with the ship obviously if you are storing energy its better to bring it with you.

My view of scientific possibility isn't exaggerated but you can feel free to think so i know Dyson spheres are a pipe dream but for a theoretical for something like that it still works.


What you just said does not make very much sense.

I am a theoretical physicist, and I am telling you right now that we physicists and engineers already know that Dyson spheres are a terrible idea: a Dyson sphere possesses no internal gravitational field and thus could easily drift into the sun. No magical idea or theory anyone might possibly think up in the future will change that. So no, it does not work. I could imagine all sorts of scenarios - a shrink ray, for example - but that doesn't mean they're possible. (Shrink rays are impossible, by the way.) Thinking about such things might be fun and interesting, and they might even lead to new ideas - Einstein famously imagined what it'd be like to run alongside a beam of light at the speed of light - but none of that makes them any less impossible.



I never said they were possible i did use the idea of a dyson sphere but whether it's possible isn't relevant imo.

The main idea behind it is what is relevant the usage of and harnessing of the suns power.
No magical idea will change what's impossible and that is true however there is so much about the universe we don't understand to say humans know the limits of what is possible and impossible is very flaky at best.

So yes it is impossible for now and most likely FOREVER however with science there is always an area of uncertainty because humans just are highly unlikely to discover everything.

I don't know whether you are a real theoretical physicist or not but i'm not going to make assumptions but if you are then surely you can grasp that basic concept that anyone with an avid interest in science understands.

Playing around with idea no matter how impossible can be very good because those impossible ideas can lead us to thinking of possible ideas.

The Dyson sphere may not be possible however the idea of harnessing the suns energy is most likely impossible in a way you could say we already do this via solar power.

I will admit my way of thinking confuses most people so i don't blame you for thinking that what i said does not make very much sense but i do agree with you but i also see those ideas as an opportunity.
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Posted 2/23/17

Ryulightorb wrote:

I don't know whether you are a real theoretical physicist or not but i'm not going to make assumptions but if you are then surely you can grasp that basic concept that anyone with an avid interest in science understands.

Playing around with idea no matter how impossible can be very good because those impossible ideas can lead us to thinking of possible ideas.



I literally made exactly that point in my previous post:


auroraloose wrote:

Thinking about such things might be fun and interesting, and they might even lead to new ideas - Einstein famously imagined what it'd be like to run alongside a beam of light at the speed of light - but none of that makes them any less impossible.


So yes, I do grasp it. And I am in fact a theoretical physicist.


Ryulightorb wrote:

No magical idea will change what's impossible and that is true however there is so much about the universe we don't understand to say humans know the limits of what is possible and impossible is very flaky at best.


Humans do not know everything that is possible and impossible, that's correct. And there is a lot we don't know. But there are things we do know, and some of those things take the form of no-go statements. Like that perpetual motion is impossible, or that shrink rays are impossible - or that you could make a Dyson sphere if you really wanted, but it'd crash into the sun and you'd have wasted a truly ridiculous amount of effort.
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Posted 2/23/17

auroraloose wrote:


Ryulightorb wrote:

I don't know whether you are a real theoretical physicist or not but i'm not going to make assumptions but if you are then surely you can grasp that basic concept that anyone with an avid interest in science understands.

Playing around with idea no matter how impossible can be very good because those impossible ideas can lead us to thinking of possible ideas.



I literally made exactly that point in my previous post:


auroraloose wrote:

Thinking about such things might be fun and interesting, and they might even lead to new ideas - Einstein famously imagined what it'd be like to run alongside a beam of light at the speed of light - but none of that makes them any less impossible.


So yes, I do grasp it. And I am in fact a theoretical physicist.


Ryulightorb wrote:

No magical idea will change what's impossible and that is true however there is so much about the universe we don't understand to say humans know the limits of what is possible and impossible is very flaky at best.


Humans do not know everything that is possible and impossible, that's correct. And there is a lot we don't know. But there are things we do know, and some of those things take the form of no-go statements. Like that perpetual motion is impossible, or that shrink rays are impossible - or that you could make a Dyson sphere if you really wanted, but it'd crash into the sun and you'd have wasted a truly ridiculous amount of effort.


I know you made that point i was just reitirating.
That is very true though
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Posted 2/23/17 , edited 2/23/17

auroraloose wrote:

Dyson spheres are impossible and absurd. The gravitational field inside a uniform shell is exactly zero, so that (i) you wouldn't be able to stand on the inner surface, and (ii) the shell would have nothing to keep it centered on the star. Giant interconnected units could form a net or ring, though.


I disagree with you on this one. The CENTER of a hollow, uniform sphere would be at zero g, but since gravitational force decreases with distance, you would, while standing on the interior surface, be pulled much more strongly toward the nearby mass (the "ground") than toward the center of the sphere. There are even places on Earth where this occurs: I recall there's a place in Oregon state with a massive nickel-iron meteorite mass in a mountain (much more dense than the average rock) which exerts sufficient gravitational pull that it actually alters the direction of "down" noticeably off from the horizon/ center of the Earth (like... 10 or 15 degrees off level).

Think of it this way: Jupiter puts out a lot more gravity than does Earth, but toward which do you fall? Of course, in order to have earth gravity, the shell of the sphere would need to be REALLY thick (though if made of denser material than average earth density, you could probably get away with around 1/6 to 1/10 the diameter of Earth.in thickness) And of course, adding significant outward force via rotation (centrifugal) would require spinning it up to much higher speed than is practical. (edit: no, wait... you would have to, if it was in Earth's orbital distance, spin it at twice Earth's orbital speed. Of course... that would only provide 1g at the Dyson sphere's "equator")

The real problem is that you have to find all that mass to MAKE a Dyson sphere, before you can make one. There just isn't enough mass in the Solar system to build one.


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Posted 2/23/17 , edited 2/23/17

outontheop wrote:


auroraloose wrote:

Dyson spheres are impossible and absurd. The gravitational field inside a uniform shell is exactly zero, so that (i) you wouldn't be able to stand on the inner surface, and (ii) the shell would have nothing to keep it centered on the star. Giant interconnected units could form a net or ring, though.


I disagree with you on this one. The CENTER of a hollow, uniform sphere would be at zero g, but since gravitational force decreases with distance, you would, while standing on the interior surface, be pulled much more strongly toward the nearby mass (the "ground") than toward the center of the sphere. There are even places on Earth where this occurs: I recall there's a place in Oregon state with a massive nickel-iron meteorite mass in a mountain (much more dense than the average rock) which exerts sufficient gravitational pull that it actually alters the direction of "down" noticeably off from the horizon/ center of the Earth (like... 15 or 20 degrees off).

Think of it this way: Jupiter puts out a lot more gravity than does Earth, but toward which do you fall? Of course, in order to have earth gravity, the shell of the sphere would need to be REALLY thick (though if made of denser material than average earth density, you could probably get away with around 1/6 to 1/10 the diameter of Earth.in thickness) And of course, adding significant outward force via rotation (centrifugal) would require spinning it up to much higher speed than is practical.

The real problem is that you have to find all that mass to MAKE a Dyson sphere, before you can make one. There just isn't enough mass in the Solar system to build one.




You learn the Shell theorem in freshman physics: the gravitational field inside a uniform hollow sphere is exactly zero at every point inside the sphere. I won't prove it for you here, because I can't type integrals or equations, but conceptually here's how it works:

The gravitational field goes like the mass of the object over the distance to it squared. As I move away from the center of the hollow sphere in a particular direction, I get closer to one side and farther from the other - but there is then more mass on the side farther away from me. These effects cancel out, so that the field is zero.

The mountain system you mention is not the same as a uniform hollow shell.
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Posted 2/23/17 , edited 2/23/17

auroraloose wrote:


outontheop wrote:


auroraloose wrote:

Dyson spheres are impossible and absurd. The gravitational field inside a uniform shell is exactly zero, so that (i) you wouldn't be able to stand on the inner surface, and (ii) the shell would have nothing to keep it centered on the star. Giant interconnected units could form a net or ring, though.


I disagree with you on this one. The CENTER of a hollow, uniform sphere would be at zero g, but since gravitational force decreases with distance, you would, while standing on the interior surface, be pulled much more strongly toward the nearby mass (the "ground") than toward the center of the sphere. There are even places on Earth where this occurs: I recall there's a place in Oregon state with a massive nickel-iron meteorite mass in a mountain (much more dense than the average rock) which exerts sufficient gravitational pull that it actually alters the direction of "down" noticeably off from the horizon/ center of the Earth (like... 15 or 20 degrees off).

Think of it this way: Jupiter puts out a lot more gravity than does Earth, but toward which do you fall? Of course, in order to have earth gravity, the shell of the sphere would need to be REALLY thick (though if made of denser material than average earth density, you could probably get away with around 1/6 to 1/10 the diameter of Earth.in thickness) And of course, adding significant outward force via rotation (centrifugal) would require spinning it up to much higher speed than is practical.

The real problem is that you have to find all that mass to MAKE a Dyson sphere, before you can make one. There just isn't enough mass in the Solar system to build one.




You learn the Shell theorem in freshman physics: the gravitational field inside a uniform hollow sphere is exactly zero at every point inside the sphere. I won't prove it for you here, because I can't type integrals or equations, but conceptually here's how it works:

The gravitational field goes like the mass of the object over the distance to it squared. As I move away from the center of the hollow sphere in a particular direction, I get closer to one side and farther from the other - but there is then more mass on the side farther away from me. These effects cancel out, so that the field is zero.

The mountain system you mention is not the same as a uniform hollow shell.


Hm. Yes, I suppose now that I look at it closer, when you're on one side of the shell, while the local objects pull most strongly per kg of mass due to the decrease in gravitational force over distance, MOST of the mass is in the opposite direction; though each individual kg across the sphere is exerting less gravitational pull, there's a lot MORE of it out that way. Hm, my mistake.

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Posted 2/23/17

outontheop wrote:

Hm. Yes, I suppose now that I look at it closer, when you're on one side of the shell, while the local objects pull most strongly per kg of mass due to the decrease in gravitational force over distance, MOST of the mass is in the opposite direction; though each individual kg across the sphere is exerting less gravitational pull, there's a lot MORE of it out that way. Hm, my mistake.



Don't worry about it; physics is literally my job. I remember being surprised at the shell theorem - if you prove it with the divergence theorem it doesn't seem all that conceptual - but the thing about more mass being on the farther side makes conceptual sense.
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