Wow, people manage to get to their 4th year (of anything that requires even incidental use of Windows) without developing an I - must - press - Ctrl-S - every - 15 - seconds reflex?
Which would probably drive someone to do things like "...insult the Universe. That is, he would insult everybody in it. Individually, personally, one by one, and (this was the thing he really decided to grit his teeth over) in Alphabetical Order."
But once you're inside the brain, the nerve impulses have no objective meaning. "Thought transmission", if it is ever acheived by technology, won't be as simple as replaying neural impulses from one brain into another; there's no one-to-one correspondence between neurons, and certainly no corresponence to neural weights. (Odds are, we'd have to learn to use it, and it would 'just another' line of communication, not 'mind reading' as it was portrayed in past literature.
This brings up something I've wondered about: how well would the brain be able to use a new set of input impulses? If we took a simple instrument, like a compass or barometric pressure sensor, and provided that information as some set of impulses to the brain, would it be able to learn how to use it?
It's one thing to provide a type of input that the brain is familiar with - it's got to be able to learn to interpret all our normal senses when we're children. But can it learn how to use something that has never been 'standard equipment' in our ancestors?
Would you mind sharing some reasons why it's not "feesible?" Maybe you're an engineering-minded individual that has some valid concerns about building such an elevator, and maybe you're not. Some more information would assist me in determining which you are.
That's close enough to propellantless for me, I suppose, so thanks for the correction.:) For some reason, when I think "propellantless," the things that come to mind are "push-against-the-quantum-foam" and "zero-point-energy" and "warp drive" and such. Can you tell that Coast-to-Coast AM helps keep me awake while I'm working to meet a deadline?:P It's easier to stay awake when you're ROFL.
The delta-v's at the beginning and end of the trip could very well be the same, but if the total mass of the vehicle is not be the same at both ends of the trip because of propellant usage, then the actual energy expenditure to slow to capture velocity at the end of the trip will be less than the energy required to accelerate to escape velocity at the beginning of the trip. (Holy run-on sentence, Batman!) I can give some numbers to demonstrate if necessary.
True about the stopping part, although the energy/propellant required to decelerate at the end of the trip will be less than that required to accelerate in the first place. That's because you only have to stop the vehicle's mass at the end, whereas you had to accelerate both the vehicle and the deceleration propellant at the beginning of the trip.
Rough numbers: An ion engine with an exhaust velocity of 30km/sec would have to use up 327g of propellant per second to push a 1000kg vehicle at 1g. At 100% efficiency, this engine would require about 147MW of input power.
To push this vehicle for 1 hour at 1g, it would need an initial propellant load of 2245kg, and an initial power input of 477MW. For 2 hours, it would need 9531kg of propellant and 1.54GW initial input power. The initial propellant load goes up exponentially with the amount of time you want to accelerate at 1g.
Disclaimer: These numbers might be wrong; I'm a bit rusty on my differential equations. And, of course, all these calculations go out the window if someone (other than sci-fi writers) comes up with propellantless propulsion. But I'm not holding my breath for that one.
I did some testing, and found that if we are successful in building a ship that can sustain 1 g of acceleration over six days (Prometheus calls for constant thrust to keep astronauts under 1 g of gravity to maintain bone and muscle mass, so it could go a hell of a lot faster), I can send a manned mission to Neptune that will take 40 days to get there.
Somehow I doubt that the Prometheus design will 'keep the astronauts under 1g' by accelerating the entire craft at 1g for days on end, because that would require lots of propellant (probably many tens of times the mass of the actual vehicle) and energy. Maybe if I get energetic after I finish my homework and real work I'll run some numbers just for fun.
I rather expect there's some sort of centrifuge setup in the plans to maintain 'artificial gravity.'
Are you trying to help this company or jst make money?
Sometimes the best way to help a company is to give the management types lots of cool new toys to play with while allowing the 'grunt work' folks to keep doing their job with the best tools possible. This keeps the PHBs out of the way of the people actually doing the work, and still allows everyone else to be productive.
Of course not every company is composed of ignorant PHBs and smart, hard-working underlings, but in my (limited experience) it's most often better for the business overall if you can give the execs something to keep them busy.:)
They must have run some "meterology" simulations to figure out how to make their "microprozessor" run faster. Or maybe "2.5 GHz" is just another typo they didn't catch.
The only reason I've had to buy any MS Office products since maybe 95/97 is that I've got to be able to open the occasional document produced with the "latest and greatest" version. But I'm getting to the point where I'll just start telling people to send it in a different format - if it's really important that I see it, they can take a couple of minutes to convert it.
Funny how the only reason to upgrade is simply because everyone else has upgraded, not because of some new "must have" feature or big batch of bug fixes. Honestly, have there been so many innovations and advances in word processing, spreadsheets and presentations that I need to upgrade every 18 months? I don't like paying money for things I don't need.
I have been using Open Office for a while now, and I love it. There's even some areas where I think it kicks MS Office's ass, like the formula editor. I do all my math and engineering homework in Open Office whenever possible.:)
And coexisting is fine. As someone else responded, it's nice to be able to bring hundreds of e-books on that business trip on the hard drive of your laptop, so I would probably get the electronic version of any book I found valuable if it were available.
I didn't mean to imply that having a free e-book reader and a free electronic version of the book would be bad, I just meant that only having the electronic version would be bad, because it would make it harder to get it to the target audience in some cases.
I don't know about others, but I am partial to printed books. And in this situation, I would think it would be advantageous to have a hard copy. Imagine this exchange:
Me: "Hey, I would like it if you could take a look at this book and see if you think it makes a good case for using open source applications in-house."
PHB: "Sure, just leave the book with me and I'll have a look."
Me: "Well, um, it's only available as an ebook, but the reader is free."
PHB: "So I have to install something on my computer? It doesn't have a virus in it, does it? "
Me: "Well, no, but I can just print it out if that would be easier. It's only 500 pages...."
In the end, I'd rather just spend $30 to pick up a copy of the book and let him read it. Besides, I don't mind spending money on books that support and advocate open source products - even if I never directly contribute to the project(s) involved, I have provided a small amount of monetary incentive for the authors (and publishers) to provide more books and/or resources for the open source community. It's worth it, IMHO.
...and when it doesn't work, and everybody has become accustomed to it being automated, nobody knows where to find the valve, turn the switch, etc., and it's a total CF. Hopefully the Navy will combine the crew reduction with much more thorough training to make sure everybody still knows how to do things manually when the automated systems go down. Because they will.
My information could be wrong here, but when I was in the Navy, I asked some Gunners Mates on my ship about the ship being able to shoot itself. They said there are mechanical stops in the turret rotating equipment to physically prevent it from being able to target any part of the ship.
Missle systems might be another matter; the protection wouldn't be as 'solid and reliable' as the big honkin block of metal that stops the gun turret, but I would be willing to bet that a lot of time and money went into preventing them from accidentally (or intentionally) hitting the ship that launched them.
Believe me, if it were possible for a ship to shoot itself, some unlucky squid would be doing it about as often as we manage to accidentally shoot other friendly objects.
That's not to say that they can't be good at it, though. It seems that women will study harder and get better grades, but its gonna be guys hanging out after class discussing the stuff in the pub because they have a genuine interest. Just my two cents.
Based on my limited experience, few people in general want to discuss such things when they're off the clock, be they male or female. One of my friends at my last job enjoyed talking EE stuff with me on breaks and after work, and she was more likely to talk about such things than many of the guys were.
As for talking about TCP/IP, kernel hacking, or quantum mechanics on a date, I would love to have a date that's as interested in techie subjects as I am. And I'm sure that there are many women out there that would enjoy such subjects as much as men, if they were encouraged to pursue them as much as men are. Just my 2.718281828 cents.:)
I wonder if the professor even realized at the time that he made that assumption. Not that it excuses him - in fact, I don't know which is worse: knowingly retaining a world view that would produce such assumptions, or being so lacking in the ability/drive to examine himself that he is blind to his prejudices.
Have you ever put these people on the spot when they say things like this? I would be interested to know what they would say (after they got over the shock of having it pointed out - because I'll bet they would probably consider it almost rude of you to do so).
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Wow, people manage to get to their 4th year (of anything that requires even incidental use of Windows) without developing an I - must - press - Ctrl-S - every - 15 - seconds reflex?
I hope you don't have a static buffer allocated for those messages, because it'll....ummm...overflow.
My POPFile statistics say that 63.02% of my email is spam, so it must be me. 15,777 spams so far this year!
"Immortality consists largly of bordom"
Which would probably drive someone to do things like "...insult the Universe. That is, he would insult everybody in it. Individually, personally, one by one, and (this was the thing he really decided to grit his teeth over) in Alphabetical Order."This brings up something I've wondered about: how well would the brain be able to use a new set of input impulses? If we took a simple instrument, like a compass or barometric pressure sensor, and provided that information as some set of impulses to the brain, would it be able to learn how to use it?
It's one thing to provide a type of input that the brain is familiar with - it's got to be able to learn to interpret all our normal senses when we're children. But can it learn how to use something that has never been 'standard equipment' in our ancestors?
And here's one for the spelling Nazis.
Would you mind sharing some reasons why it's not "feesible?" Maybe you're an engineering-minded individual that has some valid concerns about building such an elevator, and maybe you're not. Some more information would assist me in determining which you are.
That's close enough to propellantless for me, I suppose, so thanks for the correction. :) For some reason, when I think "propellantless," the things that come to mind are "push-against-the-quantum-foam" and "zero-point-energy" and "warp drive" and such. Can you tell that Coast-to-Coast AM helps keep me awake while I'm working to meet a deadline? :P It's easier to stay awake when you're ROFL.
The delta-v's at the beginning and end of the trip could very well be the same, but if the total mass of the vehicle is not be the same at both ends of the trip because of propellant usage, then the actual energy expenditure to slow to capture velocity at the end of the trip will be less than the energy required to accelerate to escape velocity at the beginning of the trip. (Holy run-on sentence, Batman!) I can give some numbers to demonstrate if necessary.
True about the stopping part, although the energy/propellant required to decelerate at the end of the trip will be less than that required to accelerate in the first place. That's because you only have to stop the vehicle's mass at the end, whereas you had to accelerate both the vehicle and the deceleration propellant at the beginning of the trip.
Someone must have revised the speed of light since I last checked, because I get (ignoring relativistic stuff because the speeds are so small):
So you'd need to manage 1g for about 3 and a half days to get to 0.01c. Perhaps you used c=186,000m/sec instead of 3x10^8 m/sec?
Rough numbers: An ion engine with an exhaust velocity of 30km/sec would have to use up 327g of propellant per second to push a 1000kg vehicle at 1g. At 100% efficiency, this engine would require about 147MW of input power.
To push this vehicle for 1 hour at 1g, it would need an initial propellant load of 2245kg, and an initial power input of 477MW. For 2 hours, it would need 9531kg of propellant and 1.54GW initial input power. The initial propellant load goes up exponentially with the amount of time you want to accelerate at 1g.
Disclaimer: These numbers might be wrong; I'm a bit rusty on my differential equations. And, of course, all these calculations go out the window if someone (other than sci-fi writers) comes up with propellantless propulsion. But I'm not holding my breath for that one.
Somehow I doubt that the Prometheus design will 'keep the astronauts under 1g' by accelerating the entire craft at 1g for days on end, because that would require lots of propellant (probably many tens of times the mass of the actual vehicle) and energy. Maybe if I get energetic after I finish my homework and real work I'll run some numbers just for fun.
I rather expect there's some sort of centrifuge setup in the plans to maintain 'artificial gravity.'
Sometimes the best way to help a company is to give the management types lots of cool new toys to play with while allowing the 'grunt work' folks to keep doing their job with the best tools possible. This keeps the PHBs out of the way of the people actually doing the work, and still allows everyone else to be productive.
Of course not every company is composed of ignorant PHBs and smart, hard-working underlings, but in my (limited experience) it's most often better for the business overall if you can give the execs something to keep them busy. :)
They must have run some "meterology" simulations to figure out how to make their "microprozessor" run faster. Or maybe "2.5 GHz" is just another typo they didn't catch.
Well, duh! Of course the majority of Slashdotters are running Windows; how else are they going to sit and read Slashdot at work all day? :)
The only reason I've had to buy any MS Office products since maybe 95/97 is that I've got to be able to open the occasional document produced with the "latest and greatest" version. But I'm getting to the point where I'll just start telling people to send it in a different format - if it's really important that I see it, they can take a couple of minutes to convert it.
Funny how the only reason to upgrade is simply because everyone else has upgraded, not because of some new "must have" feature or big batch of bug fixes. Honestly, have there been so many innovations and advances in word processing, spreadsheets and presentations that I need to upgrade every 18 months? I don't like paying money for things I don't need.
I have been using Open Office for a while now, and I love it. There's even some areas where I think it kicks MS Office's ass, like the formula editor. I do all my math and engineering homework in Open Office whenever possible. :)
And coexisting is fine. As someone else responded, it's nice to be able to bring hundreds of e-books on that business trip on the hard drive of your laptop, so I would probably get the electronic version of any book I found valuable if it were available.
I didn't mean to imply that having a free e-book reader and a free electronic version of the book would be bad, I just meant that only having the electronic version would be bad, because it would make it harder to get it to the target audience in some cases.
I don't know about others, but I am partial to printed books. And in this situation, I would think it would be advantageous to have a hard copy. Imagine this exchange:
In the end, I'd rather just spend $30 to pick up a copy of the book and let him read it. Besides, I don't mind spending money on books that support and advocate open source products - even if I never directly contribute to the project(s) involved, I have provided a small amount of monetary incentive for the authors (and publishers) to provide more books and/or resources for the open source community. It's worth it, IMHO.
hmmmm...if I send a square wave down a wire, can I get a discount for all the sine waves I used to make the square wave? :P
Really? I thought it was either an offer to refinance someone's mortgage or to tell them they'd won a trip to London.
...and when it doesn't work, and everybody has become accustomed to it being automated, nobody knows where to find the valve, turn the switch, etc., and it's a total CF. Hopefully the Navy will combine the crew reduction with much more thorough training to make sure everybody still knows how to do things manually when the automated systems go down. Because they will.
My information could be wrong here, but when I was in the Navy, I asked some Gunners Mates on my ship about the ship being able to shoot itself. They said there are mechanical stops in the turret rotating equipment to physically prevent it from being able to target any part of the ship.
Missle systems might be another matter; the protection wouldn't be as 'solid and reliable' as the big honkin block of metal that stops the gun turret, but I would be willing to bet that a lot of time and money went into preventing them from accidentally (or intentionally) hitting the ship that launched them.
Believe me, if it were possible for a ship to shoot itself, some unlucky squid would be doing it about as often as we manage to accidentally shoot other friendly objects.
Based on my limited experience, few people in general want to discuss such things when they're off the clock, be they male or female. One of my friends at my last job enjoyed talking EE stuff with me on breaks and after work, and she was more likely to talk about such things than many of the guys were.
As for talking about TCP/IP, kernel hacking, or quantum mechanics on a date, I would love to have a date that's as interested in techie subjects as I am. And I'm sure that there are many women out there that would enjoy such subjects as much as men, if they were encouraged to pursue them as much as men are. Just my 2.718281828 cents. :)
I wonder if the professor even realized at the time that he made that assumption. Not that it excuses him - in fact, I don't know which is worse: knowingly retaining a world view that would produce such assumptions, or being so lacking in the ability/drive to examine himself that he is blind to his prejudices.
Have you ever put these people on the spot when they say things like this? I would be interested to know what they would say (after they got over the shock of having it pointed out - because I'll bet they would probably consider it almost rude of you to do so).