If you're just talking about highly efficient machines, we already know what the limits are to a large extent. A heat engine can never exceed the Carnot limit, for instance. All machines are entropy limited.
I would be surprised if they _didn't_ build in a few centuries, and I think the guy in the article is being woefully reluctant to think about it a tiny bit.
A Dyson sphere in the form of a solid shell around a star is probably physically impossible, but a Dyson sphere in the form of billions of tiny orbiting satellites (which this anomaly could possibly be) is very possible and could be constructed in a distributed way. If there is some incentive for a person or company to build a solar satellite - say, to rent out its real estate - and this becomes profitable, the market will drive the exponential growth to make it happen. If it's a good investment opportunity, they'll start popping up all over the place and soon there will have to be regulations to keep people from building new ones.
You wrote 11 paragraphs on how islamic culture is being forced upon you yet not even a single mention of where you live... yeah I'm calling bullshit unless you actually provide useful info that backs up your experience
I want the best people to come to my country. I want doctors and engineers and hard workers. I don't give two shits if they're muslim or christian or buddhist or atheist. If I go to a doctor to get heart surgery, I don't care if the doctor is a muslim, I care if he's a good doctor. And so what if he's muslim anyway. His kids or his grandkids will be atheist, like everyone else's kids.
> maybe it's their own children who will rather become Europeans at heart rather than Muslims
This is in fact what's happening. Religion is in rapid decline all over the world. Christians may cry about this, but it affects all religions equally. Yet some people seem to think that islam is something that is inherited through one's DNA.
Anyway, I'm not espousing a pro- or anti-immigration position. I'm just saying that the arguments given against immigration usually tend to be extremely absurd, often bizarrely absurd.
You think muslims around the world are all part of some grand conspiracy to 'take revenge' for the crusades? No, they're just people who see the much greater opportunities and wealth available in European countries compared to the shitholes they live in, and make the rational decision to move there for personal gain.
As for the 'decline' of Europe, they may be decreasing in number, sure, but they are definitely increasing in wealth (positive economic growth) with the effect that wealth and power is becoming concentrated in the hands of fewer individuals. Raw population size is a poor measure of the well-being of a country, otherwise India and China would be the best places to live.
They aren't going to increase the word limit. They are simply going to provide an 'extended tweet' functionality where you can add more text as an 'add-on' to your tweet.
You can already link images and shit in your tweets; and a lot of people just post images containing text. This would keep people from doing that. I can't fathom why morons are complaining about this.
The idea, sure, but so is the idea of warp drives. An idea is just fiction until someone turns it into reality.
Once something hard is achieved it ceases to be terribly remarkable. But mining asteroids or living on Mars? No way, THAT'S sci-fi, it will never happen!
This really depends how long you can keep it in stasis, how good your shielding is, and how many embryos you can take. Given good shielding and low enough temperatures, eukaryotic cells can probably be stored for at least a millenium or two with a feasible percentage of the cells surviving the journey. Beyond that, we simply don't know, but there are some ways to work around that. You could store germ line stem cells and periodically 'wake' them up to divide and repair their damage and then freeze them again, to turn them into viable gametes at the end of the journey.
I was just trying to point out what the article was saying; not defending it in any way.
But still, just ten years ago the idea that we'd have rockets that could go straight up, launch a vehicle, and then land back down and be able to shoot up to space again with just a refueling would have been dismissed as 'space nuttery', yet here we are, very nearly there.
The future may not look like how we imagine it to be. But it _will_ look different.
Anyway all of this seems moot to me. We can already freeze human beings for long periods of time. It's called 'embryo freezing' and it's commonly used.
> A static test does not expose an airframe to the same stress as an actual launch and bringing it back down.
Yes that's completely true and I never said otherwise. But the fact that SpaceX can test fire a rocket stage multiple times, launch it, and recover it again give high confidence to their ability to be able to re-use a launched rocket, simply because so much of what could go wrong in an actual mission could also go wrong in a test firing.
It would be very, very strange if it cost $70 million to 're-certify' a falcon 9 first stage. I can't find the source right now but I remember reading that refurbishment costs are estimated around $0.5 million, and it would be strange if the certification cost were greater (or even equal to) the refurbishment cost.
The current Merlin engine design can go through about ~20 full-duration firings without any issues. I wouldn't be surprised if they could eventually get it up to ~100 firings or more.
It's easy to pretend to know stuff. Everyone and their mother nowadays seems to be an expert on rocketry.
It's harder to actually know stuff. The most important causes for failure on rockets are engine failures, software failures, and structural failures, in that order. Engine failures are typically caused by excessive vibration, thermal stress, combustion containment failures (hot gases touching the walls), turbopump failures, and a few other reasons, and these will often show up in static tests. In fact this is the whole point of static testing. As for software, it's the same whether you're re-using an airframe or not. Finally, as for structural failures, they are caused by vibration, thermal stress, and aerodynamic stress. Of these, a pretty good picture can be constructed from static testing, with only aerodynamic stresses left out. Granted, a single-engine test isn't very accurate for diagnosing problems; full-rocket static tests are better.
While flying through the air in a normal mission profile puts a lot of stress on the airframe, it doesn't do any irreversible damage on the airframe, unless the rocket is very badly designed. Going outside the mission profile (facing the wind the wrong way) can and will do irreversible damage, but spacex are very careful to bring their rockets down gently. If you want to bet that a recovered falcon 9 first stage can't be used, the only way that argument will work is if you argue that the airframe somehow suffers irreversible damage during the recovery maneuver. Other than this, it would be extremely strange.
A rocket doesn't become damaged and non-recoverable just because it flew for five minutes through the air. The only reason people haven't been able to recover rockets up to now is because the actual act of taking a large moving object at 5000 km/h, decelerating it, maneuvering it through the atmosphere, and landing it gently is really really hard. That, and the thermal stresses on the engines mean that most rocket engines up to now have not been able to sustain multiple full-length firings without refurbishment.
SpaceX has _already_ demonstrated that it has solved both of these problems. The Merlin rockets that SpaceX uses are actually fired around 10 times before even getting mounted on an actual launch vehicle! And no, they aren't 'refurbished' after test firing. The engines have been designed with full re-usability in mind - fill up the tank again and go. The launch vehicles themselves go through static firings before being launched through space. In static firings they get most of the vibration and thermal stresses that they would get if they were actually flying (most of these stresses come from the rocket engines). The point is that SpaceX is already 're-using' its stages. It's just that it has never re-used one that has not been strapped down to the ground. Given all of this, it would be MIGHTY strange if boosters that had flown could not be re-used.
If you're betting on this being the case, don't. You'll probably lose the bet.
It's best to describe Star Wars as fantasy transplanted into a sci-fi setting. Planets take the place of cities, spaceships take the place of ships, and lightsabers take the place of swords. And the Death Star takes the place of the Magical Weapon of Doom (The one ring, the ark of the covenant, the soul cube, etc.). But if you switch all of that back you still get a completely coherent story.
Sci-fi ranges the spectrum from 'hard' (completely plausible in princple) to 'soft' (sufficiently advanced technology), so you can't really say the presence of magic per se disqualifies something as sci-fi. Instead, it's what you do with the magic that counts. My personal interpretation is that good sci-fi should deal with the impact of technological developments on human society, ethics, and outlook on the future.
The whole thing felt like what would happen if you asked a jackass genie to give you a new star wars film like the originals. The genie laughs to himself and gives you The Force Awakens. Then tells you to be more careful with your next wish.
Star Wars is dead and has been dead for a long time. Deal with it.
If you look at the marketing around this movie, it was just incredible. J J Abrams was supposedly the "Best Director Ever"; a star wars fanboy and master genius. Even though he ruined Star Trek by being a bitch for his corporate masters and turning it into standard soulless Hollywood fare, don't worry! He loves Star Wars and he'll stay true to the spirit of it.
The real geniuses are the social media masters. The people who know what buttons to push and how to make things viral. They own the world now. They can sell us anything. That's the take-away lesson from this movie.
All the late night talk shows. Celebrity endorsements. Merchandising. Posters. Social media. Memes. Everyone who was 'in' on the story of the movie coming out and saying it was brilliant, amazing, and that the fans will love it. And the fans duly did what they were told and loved it
> It is amazing what a big marketing budget can do to brainwash consumers
The marketing was so pervasive that some people _need_ to believe that it was an amazing movie. They have to rationalize their beliefs and predictions for themselves.
They'll eventually come around to the truth, though.
The reason cold fusion isn't taken seriously is because it's been a consistent source of bullshit, lies, data manipulation, outright fraud, and bogus explanations.
Cold fusion didn't just lose credibility because of Fleischmann and Pons. It's lost credibility because of the 26 years of its history too. A lot of the time, reputable scientists do attempt to verify and duplicate the claims of the cold fusion people only to be rapidly turned away. The cold fusion people don't *want* real experts looking at their work. They want gullible idiots and journalists.
The shuttle program has nothing to do with this... virtually every design decision for the shuttle was different from the falcon 9.
The shuttle carried a huge non-reusable external fuel tank and the SRBs (which produced 70% of takeoff thrust) were also non-reusable. The 'main' engines were not really designed for re-use and had to be completely rebuilt after each flight. The decision to use heat tiles instead of an ablative coating meant the risk of heat tiles falling off and required very expensive refurb after each flight. The weird shape of the shuttle meant that the aerodynamics were complicated and hard to understand; Columbia was destroyed partly due to aerodynamic forces. There was no escape system in the event of failure. Much of the design was literally based on "let's get the initial program cost down so that it can be approved by congress and let people pay for our mistakes later."
The shuttle proved zip about re-usable spacecraft. It did, however, prove just how much can go wrong when you have a flawed design process based on impossible and conflicting design requirements and a manufacturing process based on pork and congressional approval.
Yes, a lot of people have proposed a plan like that, and it would in all likelihood work. But SpaceX's goals are more ambitious: They want to launch people on rockets that have been used many times. Knowing Musk, I'd bet $100 that he's going to achieve this goal.
You can - and people do - decommission nuclear reactors safely. That's not the point. The point is how much it costs to do so. Nuclear reactors are really expensive to safely decommission.
Although to be fair if you include the cost of damage to the environment that coal produces, then there's no comparison, coal is far far more expensive than any other form of power.
Slashdot Mirror
Ok... which ones? Specifics.
If you're just talking about highly efficient machines, we already know what the limits are to a large extent. A heat engine can never exceed the Carnot limit, for instance. All machines are entropy limited.
I would be surprised if they _didn't_ build in a few centuries, and I think the guy in the article is being woefully reluctant to think about it a tiny bit.
A Dyson sphere in the form of a solid shell around a star is probably physically impossible, but a Dyson sphere in the form of billions of tiny orbiting satellites (which this anomaly could possibly be) is very possible and could be constructed in a distributed way. If there is some incentive for a person or company to build a solar satellite - say, to rent out its real estate - and this becomes profitable, the market will drive the exponential growth to make it happen. If it's a good investment opportunity, they'll start popping up all over the place and soon there will have to be regulations to keep people from building new ones.
You wrote 11 paragraphs on how islamic culture is being forced upon you yet not even a single mention of where you live... yeah I'm calling bullshit unless you actually provide useful info that backs up your experience
I want the best people to come to my country. I want doctors and engineers and hard workers. I don't give two shits if they're muslim or christian or buddhist or atheist. If I go to a doctor to get heart surgery, I don't care if the doctor is a muslim, I care if he's a good doctor. And so what if he's muslim anyway. His kids or his grandkids will be atheist, like everyone else's kids.
> maybe it's their own children who will rather become Europeans at heart rather than Muslims
This is in fact what's happening. Religion is in rapid decline all over the world. Christians may cry about this, but it affects all religions equally. Yet some people seem to think that islam is something that is inherited through one's DNA.
Anyway, I'm not espousing a pro- or anti-immigration position. I'm just saying that the arguments given against immigration usually tend to be extremely absurd, often bizarrely absurd.
You think muslims around the world are all part of some grand conspiracy to 'take revenge' for the crusades? No, they're just people who see the much greater opportunities and wealth available in European countries compared to the shitholes they live in, and make the rational decision to move there for personal gain.
As for the 'decline' of Europe, they may be decreasing in number, sure, but they are definitely increasing in wealth (positive economic growth) with the effect that wealth and power is becoming concentrated in the hands of fewer individuals. Raw population size is a poor measure of the well-being of a country, otherwise India and China would be the best places to live.
Damn, and I thought my 2009 Dell laptop (still humming merrily after 6 years of daily use) was special. I'll come back in another ten years.
On that note, though, most people abuse their computers so badly they barely last 2-3 years.
You didn't even RTFA.
They aren't going to increase the word limit. They are simply going to provide an 'extended tweet' functionality where you can add more text as an 'add-on' to your tweet.
You can already link images and shit in your tweets; and a lot of people just post images containing text. This would keep people from doing that. I can't fathom why morons are complaining about this.
The idea, sure, but so is the idea of warp drives. An idea is just fiction until someone turns it into reality.
Once something hard is achieved it ceases to be terribly remarkable. But mining asteroids or living on Mars? No way, THAT'S sci-fi, it will never happen!
This really depends how long you can keep it in stasis, how good your shielding is, and how many embryos you can take. Given good shielding and low enough temperatures, eukaryotic cells can probably be stored for at least a millenium or two with a feasible percentage of the cells surviving the journey. Beyond that, we simply don't know, but there are some ways to work around that. You could store germ line stem cells and periodically 'wake' them up to divide and repair their damage and then freeze them again, to turn them into viable gametes at the end of the journey.
I was just trying to point out what the article was saying; not defending it in any way.
But still, just ten years ago the idea that we'd have rockets that could go straight up, launch a vehicle, and then land back down and be able to shoot up to space again with just a refueling would have been dismissed as 'space nuttery', yet here we are, very nearly there.
The future may not look like how we imagine it to be. But it _will_ look different.
1. Generation ships
2. Nuclear propulsion, antimatter propulsion
3. Science fiction (warp drives, transporters, etc.)
Anyway all of this seems moot to me. We can already freeze human beings for long periods of time. It's called 'embryo freezing' and it's commonly used.
> A static test does not expose an airframe to the same stress as an actual launch and bringing it back down.
Yes that's completely true and I never said otherwise. But the fact that SpaceX can test fire a rocket stage multiple times, launch it, and recover it again give high confidence to their ability to be able to re-use a launched rocket, simply because so much of what could go wrong in an actual mission could also go wrong in a test firing.
It would be very, very strange if it cost $70 million to 're-certify' a falcon 9 first stage. I can't find the source right now but I remember reading that refurbishment costs are estimated around $0.5 million, and it would be strange if the certification cost were greater (or even equal to) the refurbishment cost.
The current Merlin engine design can go through about ~20 full-duration firings without any issues. I wouldn't be surprised if they could eventually get it up to ~100 firings or more.
It's easy to pretend to know stuff. Everyone and their mother nowadays seems to be an expert on rocketry.
It's harder to actually know stuff. The most important causes for failure on rockets are engine failures, software failures, and structural failures, in that order. Engine failures are typically caused by excessive vibration, thermal stress, combustion containment failures (hot gases touching the walls), turbopump failures, and a few other reasons, and these will often show up in static tests. In fact this is the whole point of static testing. As for software, it's the same whether you're re-using an airframe or not. Finally, as for structural failures, they are caused by vibration, thermal stress, and aerodynamic stress. Of these, a pretty good picture can be constructed from static testing, with only aerodynamic stresses left out. Granted, a single-engine test isn't very accurate for diagnosing problems; full-rocket static tests are better.
While flying through the air in a normal mission profile puts a lot of stress on the airframe, it doesn't do any irreversible damage on the airframe, unless the rocket is very badly designed. Going outside the mission profile (facing the wind the wrong way) can and will do irreversible damage, but spacex are very careful to bring their rockets down gently. If you want to bet that a recovered falcon 9 first stage can't be used, the only way that argument will work is if you argue that the airframe somehow suffers irreversible damage during the recovery maneuver. Other than this, it would be extremely strange.
You know nothing about rocketry.
A rocket doesn't become damaged and non-recoverable just because it flew for five minutes through the air. The only reason people haven't been able to recover rockets up to now is because the actual act of taking a large moving object at 5000 km/h, decelerating it, maneuvering it through the atmosphere, and landing it gently is really really hard. That, and the thermal stresses on the engines mean that most rocket engines up to now have not been able to sustain multiple full-length firings without refurbishment.
SpaceX has _already_ demonstrated that it has solved both of these problems. The Merlin rockets that SpaceX uses are actually fired around 10 times before even getting mounted on an actual launch vehicle! And no, they aren't 'refurbished' after test firing. The engines have been designed with full re-usability in mind - fill up the tank again and go. The launch vehicles themselves go through static firings before being launched through space. In static firings they get most of the vibration and thermal stresses that they would get if they were actually flying (most of these stresses come from the rocket engines). The point is that SpaceX is already 're-using' its stages. It's just that it has never re-used one that has not been strapped down to the ground. Given all of this, it would be MIGHTY strange if boosters that had flown could not be re-used.
If you're betting on this being the case, don't. You'll probably lose the bet.
It's best to describe Star Wars as fantasy transplanted into a sci-fi setting. Planets take the place of cities, spaceships take the place of ships, and lightsabers take the place of swords. And the Death Star takes the place of the Magical Weapon of Doom (The one ring, the ark of the covenant, the soul cube, etc.). But if you switch all of that back you still get a completely coherent story.
Sci-fi ranges the spectrum from 'hard' (completely plausible in princple) to 'soft' (sufficiently advanced technology), so you can't really say the presence of magic per se disqualifies something as sci-fi. Instead, it's what you do with the magic that counts. My personal interpretation is that good sci-fi should deal with the impact of technological developments on human society, ethics, and outlook on the future.
The whole thing felt like what would happen if you asked a jackass genie to give you a new star wars film like the originals. The genie laughs to himself and gives you The Force Awakens. Then tells you to be more careful with your next wish.
Star Wars is dead and has been dead for a long time. Deal with it.
If you look at the marketing around this movie, it was just incredible. J J Abrams was supposedly the "Best Director Ever"; a star wars fanboy and master genius. Even though he ruined Star Trek by being a bitch for his corporate masters and turning it into standard soulless Hollywood fare, don't worry! He loves Star Wars and he'll stay true to the spirit of it.
The real geniuses are the social media masters. The people who know what buttons to push and how to make things viral. They own the world now. They can sell us anything. That's the take-away lesson from this movie.
All the late night talk shows. Celebrity endorsements. Merchandising. Posters. Social media. Memes. Everyone who was 'in' on the story of the movie coming out and saying it was brilliant, amazing, and that the fans will love it. And the fans duly did what they were told and loved it
> It is amazing what a big marketing budget can do to brainwash consumers
The marketing was so pervasive that some people _need_ to believe that it was an amazing movie. They have to rationalize their beliefs and predictions for themselves.
They'll eventually come around to the truth, though.
Precisely.
The reason cold fusion isn't taken seriously is because it's been a consistent source of bullshit, lies, data manipulation, outright fraud, and bogus explanations.
Cold fusion didn't just lose credibility because of Fleischmann and Pons. It's lost credibility because of the 26 years of its history too. A lot of the time, reputable scientists do attempt to verify and duplicate the claims of the cold fusion people only to be rapidly turned away. The cold fusion people don't *want* real experts looking at their work. They want gullible idiots and journalists.
The shuttle program has nothing to do with this... virtually every design decision for the shuttle was different from the falcon 9.
The shuttle carried a huge non-reusable external fuel tank and the SRBs (which produced 70% of takeoff thrust) were also non-reusable. The 'main' engines were not really designed for re-use and had to be completely rebuilt after each flight. The decision to use heat tiles instead of an ablative coating meant the risk of heat tiles falling off and required very expensive refurb after each flight. The weird shape of the shuttle meant that the aerodynamics were complicated and hard to understand; Columbia was destroyed partly due to aerodynamic forces. There was no escape system in the event of failure. Much of the design was literally based on "let's get the initial program cost down so that it can be approved by congress and let people pay for our mistakes later."
The shuttle proved zip about re-usable spacecraft. It did, however, prove just how much can go wrong when you have a flawed design process based on impossible and conflicting design requirements and a manufacturing process based on pork and congressional approval.
Yes, a lot of people have proposed a plan like that, and it would in all likelihood work. But SpaceX's goals are more ambitious: They want to launch people on rockets that have been used many times. Knowing Musk, I'd bet $100 that he's going to achieve this goal.
You can - and people do - decommission nuclear reactors safely. That's not the point. The point is how much it costs to do so. Nuclear reactors are really expensive to safely decommission.
Although to be fair if you include the cost of damage to the environment that coal produces, then there's no comparison, coal is far far more expensive than any other form of power.
And MUCH easier than a nuclear plant.