Now. We don't have the machinery, computers and sensors now. There is no law of nature that says it can't be done. None... Don't limit your thinking to just today!
Just because you can't do it now does not mean we won't be able to do it some time in the future. Not sure what kind of engineer you are, but clearly a pretty bad one if you think the only things we will build in the future is only what we can build today.
Once upon a time we didn't have the means to build heaver than air craft. We didn't have the means to make 4GHz transistors, or turbofans or whatever.
Seriously "we can't (don't) do that now... so it can't be done" is really lame.
This uses the transit method where the planet passes between its star and earth, so the orbital plane needs to be edge on. You also need IIRC 3 transits to be a proper observation. Thus to detect earth you need to wait at least 3 years but no more than 4. Jupiter you need to wait up to 48 years! So yes its very biased. I believe this missions max life is 7 years. And yes the planets that are further out will take longer and be announced later.
Why do you assume that they are like us. If life out there is ubiquitous, then there must be very strange species out there... Just because you think we won't does not make a case for anything else. Also you assume technology must somehow preclude methods of permitting such trips. Hibernation may be possible, especially on some alien species. Then if they are a space faring civilization, why do they need habitable planets? The need merely the raw materials to make habitats or even better are quite capable of a level of technology where many places are effectively habitable. Also note that its well within physical plausibility to go a bit faster than.01c.
The pub i was at last week was older than 500 years. My favorite wine cellar is about 700 years old. Its just not that long in the scheme of things.
Also Von Newman probes are typically suggested at the same time as my.01c example. Again i believe in the original discussion.
Sure that thousands of civilizations just can't be bothered to go anywhere may be the answer to the Fermi Paradox, one that was even suggested by Fermi IIRC. Since we have no data other than we have not observed anything, its nothing more than a assertion of course. Equally valid speculation is that intelligent life is exceptionally rare. Or that civilizations wipe themselves out etc.
Also just saying something like "no one is going to do that!" is not in fact a answer to the general plausibility of it. There are 7 billion of us, you are not like us all. I think we would find more than a few volunteers for a one way 500 year trip in deep freeze. Hell if we can pull of cryo sleep, people will probably pay money to be frozen for some centuries to get to the future.
Fermi Paradox is not just about communicating, one of the original wordings was simply traveling. Even at.01c you can colonize a galaxy in a few million years. An eye blink on the galactic scale. Now if there are many such intelligent life forms out there.....
But if there are so many cultures out there, then why is there not just a few that doesn't retreat inwards and rather expands outwards.. It would only take one.
Lets listen to Andromeda which is 2.5 million light years away or about 24x10^21 meters away. Lets assume that that the intelligent life in Andromeda only transmit to the closest galaxy, us. Lets also assume we have a perfect quantum efficiency detector at the 1.420GHz "water hole" and that we have zero noise and hence only a photon per second can be considered enough data to rule out anything but ETs. Finally we assume that we have built a 100m radius antenna to capture these photons.
Ignoring diffraction and the relative orientation of the milky way to Andromeda, we assume they only need the energy to stream that many photons through the milky way disk. The diameter of the milky way is about 100,000 lty so the area is 703x10^39 m^2. We want one photon per second per 100m radius antenna or per 31x10^3. The total number of photons per sec is 22.7x10^36. Each photon has energy E=hv or 937x10^-27J and the total power required is *only* 21x10^12W.
Obviously there are other losses and diffraction, but the real limit is the noise floor at 1.420GHz. I have no idea what that is, but once we consider shot noise etc we start to see that we need a bit more power than 21TW. However this is not an impossible power level, and is not "life sterilizing" really. But then again its only 2.5 million light years away. In terms of galactic distance, that is just over the fence. Also the guys over at Andromeda have to really want to let others know they are around. Which with the distance involved seems less likely than local civilizations.
I use to work at a gas station. The drainage system is separate from the city one. We are not allowed to just wash it down the collective drain. We are also required to clean up spills ASAP.
Its not a stupid question. Thermodynamics tells us that energy can be converted from one from to another, but that not all forms of energy are equal.
Heat and work are the 2 forms of energy we consider with heat engines and heat pumps. 1kJ of heat is *not* the same as 1kJ of work. This means if i have 1kJ of heat i can't get 1kW of work, it depends the the temperatures of the hot and cold. For example if i have a hot side temp of 25C and a cold side temp of -25C then the ideal heat engine can convert 16.8% of that heat into work, or 168J. I can also put that heat engine into reverse (we consider a perfect heat engine/pump), then i can use just 168J of work, to pump 1kJ of heat into the hot reservoir. 168J came from the work done, and 832J of heat came from the cold side. The COP is 5.9 and we get 5.9x more heat from the work done, because work energy is much more effective than heat energy.
Note that we can put two of these engines back to back, one forward and one backward and everything will balance perfectly, you don't get any energy out. So real systems with any losses, well... you get the idea. In practice, we get about half Carnot efficiency.
What? this thread is crazy. A heat pump will often have a COP for heating as high as 3 and in theory can be as high as 5. That is for 1kW of power i can pump in 3kW of heat (power) into my house. This is without invoking Maxwell demons or any magic. That is Carnot efficiency.
I cannot do this with a heat. The COP of a heater is simply 1.
I don't think that is correct. Slackware comes multilib capable. So it quite easy to make it multilib and everything works just fine with it. No where have i ever seen a "use at your own risk, this can break 64bit apps". Not only that, but it doesn't. I have this installed on 3 different desktops and 2 laptops without issues.
Lets not forget that they are also popular in Eastern Europe. Most of the students i teach in Czech had Smart phones. They seem as ubiquitous in Slovakia as well.
Lets face it, outside news reports there really is no problem here. Christmass shopping is as high as always and hot wine is selling as fast as they can heat it up here in Vienna. Debt crises? where?
True, to a point. Getting hold of the required amounts of 235U or 239Pu remain the biggest obstacles. Despite movies, it really is very strictly controlled and hard to move without a lot of people knowing about it or noticing.
What is a true climate scientist? The first full major that you could with that title was in 2000 IIRC. There seems to be a lot of real climate scientists and a lot of not real climate scientists when it suits people. And are you a climate scientist? Because if your not i shouldn't listen to you, also is wikipedia edited by real climate scientists? Or the media? I mean how many really climate scientists have you really talked to or read their papers?
In fact the "high" limits are really really low. Compared to just about everything else that bad for you, you are legally allowed to put an order of magnitude more "bad" stuff in food etc than what constitutes "high" radioactivity.
Case in point Ramsar does not have higher levels of cancer, if anything its lower, but that is not necessarily causal of course. Many people believe a threshold model for radiation damage is more accurate, but good luck getting that into law. Once you use the word radiation, rationality is out the window.
Well any thermal design will never get over a fairly low amount of equilibrium Pu-239, and yes i forgot about the "live refueling" that CANDU boasts. I was under the impression that "breading" Pu-239 will pretty much always have some other Pu isotopes that will need to be separated. Sure its less in fast reactor, but not that low i thought.
Yet if i have the same idea, build/make and sell the same stuff but don't bother with lawyers, i can be forced to stop because someone else had the same idea and just added lawyers. Independent invention is *not* a defense. Yet it happens often.
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Now. We don't have the machinery, computers and sensors now. There is no law of nature that says it can't be done. None... Don't limit your thinking to just today!
Just because you can't do it now does not mean we won't be able to do it some time in the future. Not sure what kind of engineer you are, but clearly a pretty bad one if you think the only things we will build in the future is only what we can build today.
Once upon a time we didn't have the means to build heaver than air craft. We didn't have the means to make 4GHz transistors, or turbofans or whatever.
Seriously "we can't (don't) do that now... so it can't be done" is really lame.
This uses the transit method where the planet passes between its star and earth, so the orbital plane needs to be edge on. You also need IIRC 3 transits to be a proper observation. Thus to detect earth you need to wait at least 3 years but no more than 4. Jupiter you need to wait up to 48 years! So yes its very biased. I believe this missions max life is 7 years. And yes the planets that are further out will take longer and be announced later.
Why do you assume that they are like us. If life out there is ubiquitous, then there must be very strange species out there... Just because you think we won't does not make a case for anything else. Also you assume technology must somehow preclude methods of permitting such trips. Hibernation may be possible, especially on some alien species. Then if they are a space faring civilization, why do they need habitable planets? The need merely the raw materials to make habitats or even better are quite capable of a level of technology where many places are effectively habitable. Also note that its well within physical plausibility to go a bit faster than .01c.
.01c example. Again i believe in the original discussion.
The pub i was at last week was older than 500 years. My favorite wine cellar is about 700 years old. Its just not that long in the scheme of things.
Also Von Newman probes are typically suggested at the same time as my
Sure that thousands of civilizations just can't be bothered to go anywhere may be the answer to the Fermi Paradox, one that was even suggested by Fermi IIRC. Since we have no data other than we have not observed anything, its nothing more than a assertion of course. Equally valid speculation is that intelligent life is exceptionally rare. Or that civilizations wipe themselves out etc.
Also just saying something like "no one is going to do that!" is not in fact a answer to the general plausibility of it. There are 7 billion of us, you are not like us all. I think we would find more than a few volunteers for a one way 500 year trip in deep freeze. Hell if we can pull of cryo sleep, people will probably pay money to be frozen for some centuries to get to the future.
Of course we don't have evidence to the contrary either. In summary... we need more data.
Fermi Paradox is not just about communicating, one of the original wordings was simply traveling. Even at .01c you can colonize a galaxy in a few million years. An eye blink on the galactic scale. Now if there are many such intelligent life forms out there.....
But if there are so many cultures out there, then why is there not just a few that doesn't retreat inwards and rather expands outwards.. It would only take one.
Well lets run the numbers shall we.
Lets listen to Andromeda which is 2.5 million light years away or about 24x10^21 meters away. Lets assume that that the intelligent life in Andromeda only transmit to the closest galaxy, us. Lets also assume we have a perfect quantum efficiency detector at the 1.420GHz "water hole" and that we have zero noise and hence only a photon per second can be considered enough data to rule out anything but ETs. Finally we assume that we have built a 100m radius antenna to capture these photons.
Ignoring diffraction and the relative orientation of the milky way to Andromeda, we assume they only need the energy to stream that many photons through the milky way disk. The diameter of the milky way is about 100,000 lty so the area is 703x10^39 m^2. We want one photon per second per 100m radius antenna or per 31x10^3. The total number of photons per sec is 22.7x10^36. Each photon has energy E=hv or 937x10^-27J and the total power required is *only* 21x10^12W.
Obviously there are other losses and diffraction, but the real limit is the noise floor at 1.420GHz. I have no idea what that is, but once we consider shot noise etc we start to see that we need a bit more power than 21TW. However this is not an impossible power level, and is not "life sterilizing" really. But then again its only 2.5 million light years away. In terms of galactic distance, that is just over the fence. Also the guys over at Andromeda have to really want to let others know they are around. Which with the distance involved seems less likely than local civilizations.
I use to work at a gas station. The drainage system is separate from the city one. We are not allowed to just wash it down the collective drain. We are also required to clean up spills ASAP.
Its not a stupid question. Thermodynamics tells us that energy can be converted from one from to another, but that not all forms of energy are equal.
Heat and work are the 2 forms of energy we consider with heat engines and heat pumps. 1kJ of heat is *not* the same as 1kJ of work. This means if i have 1kJ of heat i can't get 1kW of work, it depends the the temperatures of the hot and cold. For example if i have a hot side temp of 25C and a cold side temp of -25C then the ideal heat engine can convert 16.8% of that heat into work, or 168J. I can also put that heat engine into reverse (we consider a perfect heat engine/pump), then i can use just 168J of work, to pump 1kJ of heat into the hot reservoir. 168J came from the work done, and 832J of heat came from the cold side. The COP is 5.9 and we get 5.9x more heat from the work done, because work energy is much more effective than heat energy.
Note that we can put two of these engines back to back, one forward and one backward and everything will balance perfectly, you don't get any energy out. So real systems with any losses, well... you get the idea. In practice, we get about half Carnot efficiency.
What? this thread is crazy. A heat pump will often have a COP for heating as high as 3 and in theory can be as high as 5. That is for 1kW of power i can pump in 3kW of heat (power) into my house. This is without invoking Maxwell demons or any magic. That is Carnot efficiency. I cannot do this with a heat. The COP of a heater is simply 1.
My router is 3 years old from my ISP and it fully supports IPv6. Seriously what out there doesn't?
Well they are in the EU. Unless there is a joke i missed
Since i do install quite a few things via slackbuilds, do you have a list of things that don't work?
I don't think that is correct. Slackware comes multilib capable. So it quite easy to make it multilib and everything works just fine with it. No where have i ever seen a "use at your own risk, this can break 64bit apps". Not only that, but it doesn't. I have this installed on 3 different desktops and 2 laptops without issues.
Lets not forget that they are also popular in Eastern Europe. Most of the students i teach in Czech had Smart phones. They seem as ubiquitous in Slovakia as well.
Lets face it, outside news reports there really is no problem here. Christmass shopping is as high as always and hot wine is selling as fast as they can heat it up here in Vienna. Debt crises? where?
They have not shown themselves willing to play by the rules of international discourse.
This is also true of the US.
True, to a point. Getting hold of the required amounts of 235U or 239Pu remain the biggest obstacles. Despite movies, it really is very strictly controlled and hard to move without a lot of people knowing about it or noticing.
There won't be any fish left in the sea long before Acidification gets them. So don't worry about that.
If you care about our environment. AGW would *not* be at the top of the list.
Show some data. It is not a unreasonable request.
What is a true climate scientist? The first full major that you could with that title was in 2000 IIRC. There seems to be a lot of real climate scientists and a lot of not real climate scientists when it suits people. And are you a climate scientist? Because if your not i shouldn't listen to you, also is wikipedia edited by real climate scientists? Or the media? I mean how many really climate scientists have you really talked to or read their papers?
By the way I *am* a true Scotsman.
Bit late, been away.
In fact the "high" limits are really really low. Compared to just about everything else that bad for you, you are legally allowed to put an order of magnitude more "bad" stuff in food etc than what constitutes "high" radioactivity.
Case in point Ramsar does not have higher levels of cancer, if anything its lower, but that is not necessarily causal of course. Many people believe a threshold model for radiation damage is more accurate, but good luck getting that into law. Once you use the word radiation, rationality is out the window.
Well any thermal design will never get over a fairly low amount of equilibrium Pu-239, and yes i forgot about the "live refueling" that CANDU boasts. I was under the impression that "breading" Pu-239 will pretty much always have some other Pu isotopes that will need to be separated. Sure its less in fast reactor, but not that low i thought.
Yet if i have the same idea, build/make and sell the same stuff but don't bother with lawyers, i can be forced to stop because someone else had the same idea and just added lawyers. Independent invention is *not* a defense. Yet it happens often.
You can't copyright ideas any more than you can patent them. You can copyright a specific *expression* of a idea, not the idea itself.