The probability of any single individual dying from a terrorist incident prior and post to 9/11 is so vanishingly small as to be considered negligible, especially in comparison to the MUCH GREATER probability of dying in a car crash -- as 41,000 or so die annually according to the government's own statistics.
So how, pray tell, are we any "safer" by any measure any rational human being would entertain?
Is this yet again another fine example of how government wishes to manipulate us by fear of the paper lion? When car travel comes anywhere close to being as safe as air travel, then we might entertain these stats again.
The sad fact is, even if there were a 9/11-level incident every year, driving would still be far more dangerous.
Oh, but our friendly little government will seize upon any chance to yank more freedom away from us. Bush, Obama -- makes no difference. Remember that when they have all of those T-ray body scanners in every airport that will render you, your wife, and your kids nude to some pervert in a room nearby.
But I guess idiots love a false sense of security, I suppose.
You are assuming that the progress of knowledge is linear; that what we know now vs. what we'll know 100 years from now is the equivalent of what we knew then, 100 years ago, to what we know now.
I'm making no such assumption.
My main point is that it is impossible to know how much of the universe that we don't know. I personally find it almost unthinkable that we will know when we hit the limit of knowledge until 10,000 years after that point.
Seriously. Although much of knowledge seems to be converging, there are still huge swaths of physics that we don't understand, like gravity, magnetism, superconductivity, etc. Yes, we can write down equations for these things and make some predictions, but I don't think that there is anybody out there who can explain why a moving charge creates a magnetic field, for example.
Perhaps these answers will only be intellectual curiosities, but I would be very careful about making any predictions about what is NOT possible. The universe is just too marvelous and humans are just too young as a species for me to think that we're even close to figuring it out.
I would agree that we do have much to learn, but at the same time there is much that we know. When it comes to the fundamental nature of physics, we understand quite a bit about how the Universe works, but we may not have all of the whys just yet.
But even if we did have the "whys", it would be, as you say, settle our academic cravings. But believe me, I am very careful about what I state. And I would just LOVE if someone can prove me wrong by actually making interstellar space travel cheap and affordable. But the equations are very clear on this -- it will take a certain amount of energy to achieve certain velocities; issues of reaction mass and specific impulse will have to be dealt with.
We can dream up all kinds of exotic "cheats", but I want to see a "cheat" that actually works. Because we have not seen one yet nor have we observed one in nature, given the level of observations we make these days, given the physics, given the equations that are verified to increasing levels of spot-on accuracy, I am forced -- despite my own dreams -- to place the possibility of cheap and affordable interstellar travel at a low order of probability -- very low. We can do it, but it's gong to cost us BIG TIME.
Also, the likelihood that a space-faring intelligent species besides us is even close enough to be worth the while of paying that cost to come to Earth is even smaller. We are getting to the point where we may able to detect earth-like planets in nearby stars, if any, and I've heard of a couple of cases where they *think* they may have detected *something*. But even given that, and given the great efforts of the SETI project over the decades, I have to look long in the eye of the possibility of intelligent technologically-advance life being "nearby". With all the gallant efforts of SETI over the decades, there has only -- to my knowledge -- be one detection of what MAY be an intelligent signal -- the so-called "Wow Signal" that was never repeated.
It's a really big Universe, and the size of it is really incomprehensible to most humans. Physics tends to be non-intuitive, especially the physics that goes beyond normal everyday experiences. The best we can do right now is an 80-year round trip to the *nearest* star, assuming all the technical issues can be solved, and it would be at great cost, with lots of huge uncertainties. I am sure we can improve on that somewhat, but the more interesting stellar systems are going to be found much further out. 50 light-years? 100 light-years? 1000?
Trust me, I don't want to be right on this. I really don't.
My point is that although we've achieved a lot, the nature of the questions we're able to ask today demonstrate that we still don't really understand huge areas of how our universe is constructed and the physics that support it.
If we try to see a way today to make interstellar space travel cheap and affordable in the context of the limitations we know of (as you are doing) then we can only assume that it's impossible. But the whole of history has demonstrated that as advanced as technology and knowledge is at any fixed point in time, hundreds and thousands of years later what is known and achievable is vastly different. Off the scale even. And so it will be for our successors, many generations from now.
See my post somewhere else on this thread about the sigmoid nature of our understanding of the Universe.
Just because there are gaps in our understanding does not mean that our basic understanding of GR and QM are so far off that we can't draw some cautious conclusions about what is possible, what will be expensive, and what we shouldn't even bother with.
We may still do Interstellar Travel. I have some ideas of my own on how to make it "cheap and affordable", but nothing to do with circumventing the realities of Relativity and the limitation of the speed of light.
Basically, an idea I've been playing around with -- self-replicating robots that I've dubbed "Replicons". These Replicons would go out to the asteroid belt and the moons of Jupiter, etc. to to use the raw materials present to not only build more of themselves, but to also build anything we want -- including interstellar space ships of any size we want. The Orion idea could be utilized for propulsion. A trip to Alpha Centauri would take 40 years or so, so it would be a generational journey. And I know MANY would want to sign up for such a journey.
The costs here would be mainly one of time, plus the enormous initial investment to engineering and deploying the first of the Replicons to get things going.
But at least the Replicons would provide a significant ROI for its investors -- all kinds of rare earths can be had; all kinds of goods could be manufactured by these beasties. Can you imagine doing an order for a nice sleek car and having it parachuted from orbit to your front door in a few days?
The engineering challenge I see for Replicons will involve finding new ways to mine and refine -- ways that don't require a lot of water or petrochemicals. The understanding on how to do this may already be there, but just not practical to do on a world rich in water and petrochemicals. Still, it will require a lot of research and development, but I'm up for it if the funding can be had.
So, as you can see, I am not a complete killjoy on this matter. I was hoping to do something with the Repliconics idea, but I don't have the time nor the clout to pull it off right now. And due to all the misconceptions created by popular movies like "Terminator", it may prove to be a hard sell in any case.
Yes, I am being hard-nosed about this. And I can wish upon a star with the best of them. But unless we have another super-major upheaval in our current understanding of Physics on the scale of what happened 100 or so years ago (unlikely), we're wasting our time entertaining fantasies of cheap and easy interstellar travel.
Well, sure, interstellar travel may be unlikely, and you'd be willing to bet $1 million on it. But would you be willing to bet the future of humanity on it, or is a little caution in order ?
If the survival of humanity (or whatever we evolve into) is at stake, cost will cease to be a consideration.
I had to deal -- indirectly -- with PCI on a prior engagement. A major pain in the butt.
I may be OK with laws that state that "thou shalt protect thy client's information", but not with anything that tries to dictate how to do it. Law-makers know nothing about the technical aspects behind security.
"It is sheer folly to think that an advance race went through all the trouble to cross many, many light-years of intergalactic space just to say "Hi".
The enormity of the effort they would have to mount given the physics of space travel"
To a cargo cult society anything other than basic objects are magical. That is to say, cars, planes, armaments, modern technological devices, communications all are Godly stuff. They do not understand how another society can manufacture such powerful objects that they can't---so easily. You don't seem the kind to wowed by a two-day cross country car ride across the continental United States, a one time godly act. Thus, why do you assume a cargo cult mentality on intergalactic space travel? Or any other magical act from your perspective? Or are you from the Intergalactic Turnpike Authority?
I'm just being hard-nosed about this. The ETs will be governed by the same laws of physics that we are governed by. And I am not one given to magical thinking. Also, you are making the assumption that knowledge is linear, but I addressed that fallacy in a different post.
Stephen Hawking is a smart guy, but he needs to think this one through. This is not even a remotely realistic threat.
I think many brilliant and talented people like Stephen Hawking neglect the economic side of many of their otherwise wonderful adventure ideas.
I'll need to look up the Orion Project (I think that's been around for a while) but I think the estimates are on the low side. I think it would take much more than 1/10th of US's GDP to pull it off. For starters, there's all the research and engineering into many areas that would have to be done just to even make it feasible.
Let's take a look at nuclear physics/energy. If you look back ~100 years, the idea of matter and energy being interchangeable was only theoretical. If you go back ~150 years, you would probably be laughed at if you claimed that it would be possible to power an entire city with enough electricity to blot mask the stars with light, using only a piece of metal.
You are assuming that the progress of knowledge is linear; that what we know now vs. what we'll know 100 years from now is the equivalent of what we knew then, 100 years ago, to what we know now.
You couldn't be more wrong.
Knowledge is highly nonlinear. It interacts with itself, and it has wide-ranging synergistic effects. But the flipside of that is that once you hit a critical level of understanding, you quickly exhaust what you don't know that will also have huge impact on you as a civilization.
The progress of knowledge is more like the sigmoid curve than a straight line. The 20th Century represents the sharp rise in that sigmoid, and we are approaching the asymptote now.
This is more the case with (large scale) physics than it is with anything else. We're at different points of that sigmoid in other fields.
I wish I were wrong on this, and I've been trying to convince myself that I am over the years. But I don't think so.
Be grateful that we've lived at a unique time in history and have been able to witness and experience the sharp rise of that sigmoid. I think we've got more rise to see, but we're closer to that asymptote that we'd like to believe, I'm afraid.
Actually, since on one, AFAIK, has been beyond the orbit of the moon, we can't even run. So we'd better behave ourselves.
The best way to "hide" would be to end all electromagnetic activity on this planet. In essence, stop using radio, disable all satellites, darken all our cities... well, go back to living in caves. All over a fear so remotely improbable we're much more likely to see a natural extinction-level-event wipe us all out. Or perhaps way more likely to wipe ourselves out.
Silly humans. Really, we're not worth the bother. Ford Prefect was correct in his assessment of "Mostly Harmless".
Yet, somehow, we know *nothing* about gravity. We know nothing about strong and weak nuclear forces, except for that fact that they exist and we can measure their effects. But I guess that is not interesting..... why try to discover new things when we all know enough already? At least I'm glad most people that matter disagree with your argument.
We know nothing about gravity? I have sitting on my shelf a very thick book called Gravitation written by Kip Thorne, Charles Misner, and John Wheeler. Care to tell them what you just told me? Or perhaps I should drop this book on your toe to demonstrate the weight of what we know about Gravity.:-)
And yes, they may disagree, but it doesn't matter. Actually, I am hoping one of them will be inspired (or angered) enough to prove me wrong and make Interstellar Travel a reality in my lifetime. At least this time I am NOT the one being Panglossian.
Please explain me why encrypting credit cards is easy but encrypting emails is not. Unless you are linking by those fields (and if you are doing that let me cast doubt on your self claimed MySQL guru credentials) it should have exactly the same cost, actually less since once you have implemented working encryption for one field, extending it to additional fields has virtually zero cost.
I agree on that about local rules, but completely disagree on the technical aspects.
From what I understand of what Massachusetts is trying to impose is encryption of ALL personal data, not just credit cards numbers.
I never said anything about encrypting emails. I just mentioned that an idiot tried to levy taxes on emails. Yes, it's such a dumbass idea that you misread it as something else!!!!! Yes, it's that hard to believe.
You need to be able to select fields containing the customer's name and perhaps address, zip code, and some other identifying info in order to be able to do lookups, to target ads, and the like. Encrypting those fields must play havoc for performance on SQL Server. I know MySQL, but not SQL Server. Obviously indexed lookups go to hell on encrypted fields; you basically can't do it unless you have at least part of that field stored in plaintext somewhere, like in the index. And if you are doing that, what's the point of encrypting the field? MySQL as of 5.5 does not offer field-level encryption, anyway. You can encrypt the DB connection, which should be used if you are connecting to the DB across an open network. Which might make plenty of sense if you are replicating the DB across multiple sites (and many are using this approach).
I just don't see what sense it makes to encrypt the entire filesystem. More importantly, what does politicians and bureaucrats know about filesystems, anyway?
We are doing things that seemed difficult on an immense scale: Fission and Fusion.
There is a difference with seeming difficult and actually BEING difficult. We are not just talking splitting and smashing atomic nuclei; we are talking about the very fundamental nature of space-time here.
Our biggest hope is that Einstein was wrong somehow. So far, all of his theories about Relativity have been holding up, with the possible exception of the fine-structure "constant" evolving over time. But even that is time on a cosmological scale. Don't see how that could give us cheap and affordable interstellar travel.
"640K ought to be enough for anybody..." This was said only 29 human years ago; imagine what it might sound like in 1000 years.
Your assumptions are based on our current notions of physics.
"Current notions of Physics"? And just where do you expect physics to go?
Let me explain it this way.
Let's define T as being the actual truth about the Universe -- from a physical standpoint.
Let us also define H as human's understanding of T.
T is an invariant quality. It's not going to change. As best us humans can do is to push H as close to T as we can get it.
We have made incredible strides at moving H very close to T -- at least as far as what is practical. We understand gravity enough to construct the GPS network, which *must* take into account General Relativity. We are doing amazing things with condense matter physics. We are capable of doing measurements to 10 or 12 decimal places on various constants and relationships of qualities in our Universe.
Let's take GR, for example. Scientists over the decades have been verifying GR to an ever increasing degree of accuracy. It still holds. It still holds.
On the other front, Quantum Physics, we build ever bigger and bigger particle accelerators to probe deeper into the nature of matter. On that front, we do keep turning up new surprises. But very few of those new surprises turn out to be something really useful, as to transform our lives like the discovery of electricity did way back when.
So, do you see the pattern here? In a very, VERY short timeframe, we have moved H quite close to T. The remaining delta has not been turning up much in the way of being earth-shattering, except at how we can manipulate and shape and rearrange baryonic matter to make it sing, roll over, dance, and play dead. On that front, there is much to be discovered.
But to make interstellar travel cheap and affordable by mere mortal civilizations, such as ours, requires progress and revolution in our understanding of the fundamentals of this Universe to reveal, perhaps, something we've missed so far.
Problem is, we keep improving our measurements and finding out that much of what we do know is "spot on" to within an ever increasing small margin of error. That's actually BAD NEWS for those of us hoping for a breakthru to make interstellar travel a reality.
Resorting to quips and anecdotes will only proffer false hopes at this point. The details are everything. As H -> T, I become even more convinced that we are stuck with what we know and understand today, with perhaps a few niggling refinements here and there that won't deliver the titanic breakthroughs we need.
As always, I would LOVE to be proven wrong about my above assessment. But you tell me. You see any holes in my reasoning, in a way that is more substantial than the usual Pollyanna approach of "gee, anything's possible because we don't know everything?" Help me out here.
The Dunning–Kruger effect is a cognitive bias in which "people reach erroneous conclusions and make unfortunate choices but their incompetence robs them of the metacognitive ability to realize it."[1] The unskilled therefore suffer from illusory superiority, rating their own ability as above average, much higher than in actuality; by contrast, the highly skilled underrate their abilities, suffering from illusory inferiority. This leads to a perverse result where less competent people will rate their own ability higher than more competent people. It also explains why actual competence may weaken self-confidence because competent individuals falsely assume that others have an equivalent understanding. "Thus, the miscalibration of the incompetent stems from an error about the self, whereas the miscalibration of the highly competent stems from an error about others."[1]
“ In the modern world the stupid are cocksure while the intelligent are full of doubt. ”
— Bertrand Russell[2][3]
Interesting reference. However, you hardly know anything about me, so perhaps you have fallen prey to the Dunning-Kruger effect yourself.:-)
But while we're on the subject, let me continue.
I've been in the computer field for over 30 years. I got my start with the Apple ][, back in 1978, when I was 16. A couple of years later, I was writing an OS from scratch for the Micronova and Nova 4X computers (Data General). It was wicked cool stuff. And I was only 18.
My entire computer career shot off from there. I have never had formal education in Computer Science, and yet I've done just about everything you can imagine.
I know what I'm good at, as is demonstrated by what I've accomplished. I even have a software patent, though many here would decry such a beast -- as do I, in part. But hey, I got paid good money for it, so I went with it.
Slash me to pieces for tooting my own horn. Actually, I only mentioned to "guru" bit in passing, as a short-hand for stating that I kinda know something about databases in high-demand environments, without having to spend an entire paragraph doing the same. If you want to pick it to death, go straight ahead and do so. Sheesh.
However, despite all of that, I do find the Dunning-Kruger reference interesting. I have been back and forth many times with assuming everyone has my level of understanding, and thinking I'm a stupid idiot despite evidence to the contrary. These days, I simply call an ace an ace. I know what I can do, I know what I am capable of, so why be shy about it? Do I know everything? No. I would never claim such. However, If I do know something, what's wrong with just being honest about it? Why is it some get offended at this? I put in the Blood, Sweat, Tears, and Years getting to where I am. Should I not be proud of that? What does modesty buy me?
I've had bloody enough of beating myself into the ground for this or that, and I refuse to do it anymore. I am an empiricist; I go by observations. And I have observed many others referring to myself as "guru", "genius", "brilliant", and what not. Quite frankly, I don't think all of those monikers are deserved. But then, I should give myself credit for what I have accomplished.
So sorry you are peeved. Actually, I'm not sorry that you are. That's your problem. Not mine.
and realise that to easily comply with this law, you encrypt the filesystem underneath the database, not the data in the database itself.
Then again, anybody who declares themselves to be a guru at something probably is suffering from the Dunning–Kruger effect.
Others -- many others -- HAVE declared me a guru.
And do you have any idea the performance impact it would have on the database server to encrypt the underlying file system? You've obviously not worked with high-demand, high traffic websites before. You would totally fail at any major social networking website with that approach. You MIGHT get away with that approach in a high-read low-write scenario, but social websites tend to have a high-read high-write setup.
Coupled with issues of backup, maintenance, and what not, you'd send the system administrators screaming for your blood.
What do you think would happen to Facebook, say, if they had to encrypt all of their database servers -- and to say they have a thousand db servers is probably low-balling it. For sure it would destabilize their entire operation, and they would have to spend millions on equipment upgrades, probably go with hardware encryption options, and backups would be nightmarish, as they would have to be encrypted too.
Take my advice. Don't bother trying to get a job in the social networking arena.
don't think it's just that we can't "think out of the physics box". I'm saying that it is extremely unlikely that anything lies outside of that "physics box" that we'd (or any other civilization) find useful for interstellar space travel.
100 years ago we knew about the atom but no scientist at that time that could even begin to phantom the of power and energy it can generate.
We knew about it, we saw it but it took a fairly long time before we discovered what we really could do with it.
It's not so hard to imagine that a hundred years from now we have discovered new properties and uses for things we already know about now.
Fairly long time? Not really. If anything, we learned pretty darn quickly what could be done with it, as Oppenheimer and buddies clearly demonstrated.
100 years from now? Yes, we'll find new and wondrous ways to manipulate atoms. We're doing so every day with nanotech and the like.
But fining ways to get around the speed of light implications for macro objects? Don't think so. The best we have today with regards to the fundamental nature of the universe are the family of superstring theories. And I have yet to hear any of those theoreticians announce anything like a possibility for superluminal travel for macro-sized objects.
That's why I've shifted my own focus from Cosmology/GR/QM to Complex Dynamical/Chaotic/Adaptive Systems and Fractals and the like. Much wonderful progress to be made there, even in our lifetimes!
Just today I used my SSN to access my forgotten username at fidelity.com. There's no question that Fidelity needs my SSN since my activities there have tax implications, so there's no way they haven't got my number stored somewhere in their databases. I have no problem with this.
More power to you. I begrudgingly make an exception for financial institutions, though I really shouldn't have to (and they give no choice these days, anyway). But for everyone else, they can take a hike if they think I will fess up my SSNO. Maybe they can pry from my fingernails.
Yes, I believe TrueCrypt is the best encryption software. TrueCrypt meets all the requirements, including avoiding vendor lock-in.
I dunno. I kinda like the AES encryption that comes free with Linux. Does everything TrueCrypt does for free -- and I get the source code to boot in case I get exceptionally paranoid about back doors, etc.
Firstly, your point about different territories with different rules is fundamentally flawed. Many places — all of Europe, for example — already have stronger data protection laws than most of the US. This causes no earth-shattering problem with compliance. Large companies keep the data they can't legally export within their European offices. Smaller companies just outsource things like payment collection to services that guarantee any personal data will be processed securely and not transferred outside of EU borders. They were going to outsource it anyway, so the only people who lose out are services that want to handle sensitive information but can't make the same guarantees as others about security, whose flawed business model just became obsolete.
If you are in, say, Great Britain, and Great Britain says you must encrypt all your data on your hard drive, you will have to deal with that, as you are under the direct jurisdiction of Great Britain. But if you are, say, running an Internet business in Montana, and Great Britain says you must deal with your data one way to do business with their citizens, and Massachusetts claims you must deal with your data a different way to do business with their residents, etc., what will you do? You will either go bust trying to comply with all the different and conflicting rules of ever region you do business with, or you run the risk of doing something illegal in a region you do not live in.
Stating that your data must be secured is one thing; stating how it is to be secured is another thing entirely.
I worked for a major online social network once, and we ran into the inane rules of the PCI, which micromanages business dealing with credit card data about how every workstation connected to the network must be managed, no matter how isolated the workstation from the credit card servers is. Things like idle times for screen savers (with password lockdown) being just, say, 5 minutes or so. It made doing software development from multiple computers unbearable as I had to continually keep typing in the stupid password every 5 minutes -- or giggle the mouse or touch the keyboard. It simply took away attention from my development efforts.
Being micromanaged by every region you wish to do e-commerce with is no picnic. If you are a mega-corporation, you can navigate those treacherous waters. If you're a small operation, a mom-and-pop, or otherwise less than a Fortune-1000 company, good luck.
I have been the victim of identity theft myself once, and I hear you on the annoyances of getting everything set straight again. But much of that pain comes from government agencies, corporate agencies, and others that simply refuse to believe that you've been duped. Perhaps some laws should be enacted in that regard to make it easier for the victim to recover.
But, truth being told, I can never trust law-makers to get it right. I can't trust law-enforcers to do the right thing, and I certainly don't trust politicians and all of their empty promises they do every election to "finally get it right".
If the civilization we discovered was 50 light-years away, it does us no good to lub something slow in their direction, as it would take many 10s of thousands of years to actually reach them! Imagine future generations on that planet not knowing why a planet-killer suddenly entered their stellar system. Assuming they could trace the origins back to our world, would they then hijack the device, reprogram it, and lub it back in our direction to reach us thousands of years later, where no one here would even know or can recall the device was ever built (or maybe from ancient records).
Relativistic weapons? Won't work, for the following reasons:
The amount of energy required to get the payload up to relativistic speeds would be simply enormous. A significant fraction (or multiple, if you want it over 90% lightspeed) of the payload's mass equivalent in energy would be required to pull it off.
If you used a laser to propel the weapon, you eliminate the problem of having to accelerate the fuel along with the craft, but then our alien friends would get a heads-up something was coming their way 50 years from when we sent the bugger off.
To knock off an entire planet, the weapon would either have to be pretty darn big or be made of antimatter. I suppose you could send a horde of thermonuclear devices (great way to get rid of our stockpiles!!!!:-)) But having multiple devices would only complicate the propulsion issue.
A LOT of our civilization's resources would be required to do any of this on the basis of a very vague threat from something 50 light-years away. No one living today would be living by the time they arrived, even if they could, say, acheive 25% lightspeed themselves, so nothing would be done anyway.
I think we, as humans, would choose to chat rather than nuke. But the latency on that communication channel would be ominous. It'd be 100 years before we'd get back a response.
And I am completely ruling out FTL, BTW. The only things moving away from us faster than light in our Universe are those things beyond our Universe's event horizon. Not going to happen in local space.
What this all means though is that the small startup/merchant/mom-and-pop Internet operations will find it more and more expensive to swim in these waters infested with little fiefdoms everywhere with delusions of hegemony.
What, you thought this law was passed for some purpose other than that? Laws like this serve two purposes: One, to be able to put a sound bite into ads and two is to help big companies keep small competitors out of the field.
... and nothing I've seen to this time would even hint at the merest possibility of anything that could possibly make interstellar travel "cheap and affordable" my mere civilizations throughout the cosmos
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So how, pray tell, are we any "safer" by any measure any rational human being would entertain?
Is this yet again another fine example of how government wishes to manipulate us by fear of the paper lion? When car travel comes anywhere close to being as safe as air travel, then we might entertain these stats again.
The sad fact is, even if there were a 9/11-level incident every year, driving would still be far more dangerous.
Oh, but our friendly little government will seize upon any chance to yank more freedom away from us. Bush, Obama -- makes no difference. Remember that when they have all of those T-ray body scanners in every airport that will render you, your wife, and your kids nude to some pervert in a room nearby.
But I guess idiots love a false sense of security, I suppose.
Thank you Bush and Obama!
I'm making no such assumption.
My main point is that it is impossible to know how much of the universe that we don't know. I personally find it almost unthinkable that we will know when we hit the limit of knowledge until 10,000 years after that point.
Seriously. Although much of knowledge seems to be converging, there are still huge swaths of physics that we don't understand, like gravity, magnetism, superconductivity, etc. Yes, we can write down equations for these things and make some predictions, but I don't think that there is anybody out there who can explain why a moving charge creates a magnetic field, for example.
Perhaps these answers will only be intellectual curiosities, but I would be very careful about making any predictions about what is NOT possible. The universe is just too marvelous and humans are just too young as a species for me to think that we're even close to figuring it out.
Why moving charges create magnetic fields: http://galileo.phys.virginia.edu/classes/252/rel_el_mag.html
I would agree that we do have much to learn, but at the same time there is much that we know. When it comes to the fundamental nature of physics, we understand quite a bit about how the Universe works, but we may not have all of the whys just yet.
But even if we did have the "whys", it would be, as you say, settle our academic cravings. But believe me, I am very careful about what I state. And I would just LOVE if someone can prove me wrong by actually making interstellar space travel cheap and affordable. But the equations are very clear on this -- it will take a certain amount of energy to achieve certain velocities; issues of reaction mass and specific impulse will have to be dealt with.
We can dream up all kinds of exotic "cheats", but I want to see a "cheat" that actually works. Because we have not seen one yet nor have we observed one in nature, given the level of observations we make these days, given the physics, given the equations that are verified to increasing levels of spot-on accuracy, I am forced -- despite my own dreams -- to place the possibility of cheap and affordable interstellar travel at a low order of probability -- very low. We can do it, but it's gong to cost us BIG TIME.
Also, the likelihood that a space-faring intelligent species besides us is even close enough to be worth the while of paying that cost to come to Earth is even smaller. We are getting to the point where we may able to detect earth-like planets in nearby stars, if any, and I've heard of a couple of cases where they *think* they may have detected *something*. But even given that, and given the great efforts of the SETI project over the decades, I have to look long in the eye of the possibility of intelligent technologically-advance life being "nearby". With all the gallant efforts of SETI over the decades, there has only -- to my knowledge -- be one detection of what MAY be an intelligent signal -- the so-called "Wow Signal" that was never repeated.
It's a really big Universe, and the size of it is really incomprehensible to most humans. Physics tends to be non-intuitive, especially the physics that goes beyond normal everyday experiences. The best we can do right now is an 80-year round trip to the *nearest* star, assuming all the technical issues can be solved, and it would be at great cost, with lots of huge uncertainties. I am sure we can improve on that somewhat, but the more interesting stellar systems are going to be found much further out. 50 light-years? 100 light-years? 1000?
Trust me, I don't want to be right on this. I really don't.
My point is that although we've achieved a lot, the nature of the questions we're able to ask today demonstrate that we still don't really understand huge areas of how our universe is constructed and the physics that support it.
If we try to see a way today to make interstellar space travel cheap and affordable in the context of the limitations we know of (as you are doing) then we can only assume that it's impossible. But the whole of history has demonstrated that as advanced as technology and knowledge is at any fixed point in time, hundreds and thousands of years later what is known and achievable is vastly different. Off the scale even. And so it will be for our successors, many generations from now.
See my post somewhere else on this thread about the sigmoid nature of our understanding of the Universe.
Just because there are gaps in our understanding does not mean that our basic understanding of GR and QM are so far off that we can't draw some cautious conclusions about what is possible, what will be expensive, and what we shouldn't even bother with.
We may still do Interstellar Travel. I have some ideas of my own on how to make it "cheap and affordable", but nothing to do with circumventing the realities of Relativity and the limitation of the speed of light.
Basically, an idea I've been playing around with -- self-replicating robots that I've dubbed "Replicons". These Replicons would go out to the asteroid belt and the moons of Jupiter, etc. to to use the raw materials present to not only build more of themselves, but to also build anything we want -- including interstellar space ships of any size we want. The Orion idea could be utilized for propulsion. A trip to Alpha Centauri would take 40 years or so, so it would be a generational journey. And I know MANY would want to sign up for such a journey.
The costs here would be mainly one of time, plus the enormous initial investment to engineering and deploying the first of the Replicons to get things going.
But at least the Replicons would provide a significant ROI for its investors -- all kinds of rare earths can be had; all kinds of goods could be manufactured by these beasties. Can you imagine doing an order for a nice sleek car and having it parachuted from orbit to your front door in a few days?
The engineering challenge I see for Replicons will involve finding new ways to mine and refine -- ways that don't require a lot of water or petrochemicals. The understanding on how to do this may already be there, but just not practical to do on a world rich in water and petrochemicals. Still, it will require a lot of research and development, but I'm up for it if the funding can be had.
So, as you can see, I am not a complete killjoy on this matter. I was hoping to do something with the Repliconics idea, but I don't have the time nor the clout to pull it off right now. And due to all the misconceptions created by popular movies like "Terminator", it may prove to be a hard sell in any case.
Yes, I am being hard-nosed about this. And I can wish upon a star with the best of them. But unless we have another super-major upheaval in our current understanding of Physics on the scale of what happened 100 or so years ago (unlikely), we're wasting our time entertaining fantasies of cheap and easy interstellar travel.
Well, sure, interstellar travel may be unlikely, and you'd be willing to bet $1 million on it. But would you be willing to bet the future of humanity on it, or is a little caution in order ?
If the survival of humanity (or whatever we evolve into) is at stake, cost will cease to be a consideration.
http://fractopoly.com/
I may be OK with laws that state that "thou shalt protect thy client's information", but not with anything that tries to dictate how to do it. Law-makers know nothing about the technical aspects behind security.
"It is sheer folly to think that an advance race went through all the trouble to cross many, many light-years of intergalactic space just to say "Hi". The enormity of the effort they would have to mount given the physics of space travel"
To a cargo cult society anything other than basic objects are magical. That is to say, cars, planes, armaments, modern technological devices, communications all are Godly stuff. They do not understand how another society can manufacture such powerful objects that they can't---so easily. You don't seem the kind to wowed by a two-day cross country car ride across the continental United States, a one time godly act. Thus, why do you assume a cargo cult mentality on intergalactic space travel? Or any other magical act from your perspective? Or are you from the Intergalactic Turnpike Authority?
I'm just being hard-nosed about this. The ETs will be governed by the same laws of physics that we are governed by. And I am not one given to magical thinking. Also, you are making the assumption that knowledge is linear, but I addressed that fallacy in a different post.
Stephen Hawking is a smart guy, but he needs to think this one through. This is not even a remotely realistic threat.
I think many brilliant and talented people like Stephen Hawking neglect the economic side of many of their otherwise wonderful adventure ideas.
I'll need to look up the Orion Project (I think that's been around for a while) but I think the estimates are on the low side. I think it would take much more than 1/10th of US's GDP to pull it off. For starters, there's all the research and engineering into many areas that would have to be done just to even make it feasible.
Let's take a look at nuclear physics/energy. If you look back ~100 years, the idea of matter and energy being interchangeable was only theoretical. If you go back ~150 years, you would probably be laughed at if you claimed that it would be possible to power an entire city with enough electricity to blot mask the stars with light, using only a piece of metal.
You are assuming that the progress of knowledge is linear; that what we know now vs. what we'll know 100 years from now is the equivalent of what we knew then, 100 years ago, to what we know now.
You couldn't be more wrong.
Knowledge is highly nonlinear. It interacts with itself, and it has wide-ranging synergistic effects. But the flipside of that is that once you hit a critical level of understanding, you quickly exhaust what you don't know that will also have huge impact on you as a civilization.
The progress of knowledge is more like the sigmoid curve than a straight line. The 20th Century represents the sharp rise in that sigmoid, and we are approaching the asymptote now.
This is more the case with (large scale) physics than it is with anything else. We're at different points of that sigmoid in other fields.
I wish I were wrong on this, and I've been trying to convince myself that I am over the years. But I don't think so.
Be grateful that we've lived at a unique time in history and have been able to witness and experience the sharp rise of that sigmoid. I think we've got more rise to see, but we're closer to that asymptote that we'd like to believe, I'm afraid.
Actually, since on one, AFAIK, has been beyond the orbit of the moon, we can't even run. So we'd better behave ourselves.
The best way to "hide" would be to end all electromagnetic activity on this planet. In essence, stop using radio, disable all satellites, darken all our cities... well, go back to living in caves. All over a fear so remotely improbable we're much more likely to see a natural extinction-level-event wipe us all out. Or perhaps way more likely to wipe ourselves out.
Silly humans. Really, we're not worth the bother. Ford Prefect was correct in his assessment of "Mostly Harmless".
Yet, somehow, we know *nothing* about gravity. We know nothing about strong and weak nuclear forces, except for that fact that they exist and we can measure their effects. But I guess that is not interesting..... why try to discover new things when we all know enough already? At least I'm glad most people that matter disagree with your argument.
We know nothing about gravity? I have sitting on my shelf a very thick book called Gravitation written by Kip Thorne, Charles Misner, and John Wheeler. Care to tell them what you just told me? Or perhaps I should drop this book on your toe to demonstrate the weight of what we know about Gravity. :-)
And yes, they may disagree, but it doesn't matter. Actually, I am hoping one of them will be inspired (or angered) enough to prove me wrong and make Interstellar Travel a reality in my lifetime. At least this time I am NOT the one being Panglossian.
Please explain me why encrypting credit cards is easy but encrypting emails is not. Unless you are linking by those fields (and if you are doing that let me cast doubt on your self claimed MySQL guru credentials) it should have exactly the same cost, actually less since once you have implemented working encryption for one field, extending it to additional fields has virtually zero cost. I agree on that about local rules, but completely disagree on the technical aspects.
From what I understand of what Massachusetts is trying to impose is encryption of ALL personal data, not just credit cards numbers.
I never said anything about encrypting emails. I just mentioned that an idiot tried to levy taxes on emails. Yes, it's such a dumbass idea that you misread it as something else!!!!! Yes, it's that hard to believe.
You need to be able to select fields containing the customer's name and perhaps address, zip code, and some other identifying info in order to be able to do lookups, to target ads, and the like. Encrypting those fields must play havoc for performance on SQL Server. I know MySQL, but not SQL Server. Obviously indexed lookups go to hell on encrypted fields; you basically can't do it unless you have at least part of that field stored in plaintext somewhere, like in the index. And if you are doing that, what's the point of encrypting the field? MySQL as of 5.5 does not offer field-level encryption, anyway. You can encrypt the DB connection, which should be used if you are connecting to the DB across an open network. Which might make plenty of sense if you are replicating the DB across multiple sites (and many are using this approach).
I just don't see what sense it makes to encrypt the entire filesystem. More importantly, what does politicians and bureaucrats know about filesystems, anyway?
We are doing things that seemed difficult on an immense scale: Fission and Fusion.
There is a difference with seeming difficult and actually BEING difficult. We are not just talking splitting and smashing atomic nuclei; we are talking about the very fundamental nature of space-time here.
Our biggest hope is that Einstein was wrong somehow. So far, all of his theories about Relativity have been holding up, with the possible exception of the fine-structure "constant" evolving over time. But even that is time on a cosmological scale. Don't see how that could give us cheap and affordable interstellar travel.
"640K ought to be enough for anybody..." This was said only 29 human years ago; imagine what it might sound like in 1000 years.
Your assumptions are based on our current notions of physics.
"Current notions of Physics"? And just where do you expect physics to go?
Let me explain it this way.
Let's define T as being the actual truth about the Universe -- from a physical standpoint.
Let us also define H as human's understanding of T.
T is an invariant quality. It's not going to change. As best us humans can do is to push H as close to T as we can get it.
We have made incredible strides at moving H very close to T -- at least as far as what is practical. We understand gravity enough to construct the GPS network, which *must* take into account General Relativity. We are doing amazing things with condense matter physics. We are capable of doing measurements to 10 or 12 decimal places on various constants and relationships of qualities in our Universe.
Let's take GR, for example. Scientists over the decades have been verifying GR to an ever increasing degree of accuracy. It still holds. It still holds.
On the other front, Quantum Physics, we build ever bigger and bigger particle accelerators to probe deeper into the nature of matter. On that front, we do keep turning up new surprises. But very few of those new surprises turn out to be something really useful, as to transform our lives like the discovery of electricity did way back when.
So, do you see the pattern here? In a very, VERY short timeframe, we have moved H quite close to T. The remaining delta has not been turning up much in the way of being earth-shattering, except at how we can manipulate and shape and rearrange baryonic matter to make it sing, roll over, dance, and play dead. On that front, there is much to be discovered.
But to make interstellar travel cheap and affordable by mere mortal civilizations, such as ours, requires progress and revolution in our understanding of the fundamentals of this Universe to reveal, perhaps, something we've missed so far.
Problem is, we keep improving our measurements and finding out that much of what we do know is "spot on" to within an ever increasing small margin of error. That's actually BAD NEWS for those of us hoping for a breakthru to make interstellar travel a reality.
Resorting to quips and anecdotes will only proffer false hopes at this point. The details are everything. As H -> T, I become even more convinced that we are stuck with what we know and understand today, with perhaps a few niggling refinements here and there that won't deliver the titanic breakthroughs we need.
As always, I would LOVE to be proven wrong about my above assessment. But you tell me. You see any holes in my reasoning, in a way that is more substantial than the usual Pollyanna approach of "gee, anything's possible because we don't know everything?" Help me out here.
The Dunning–Kruger effect is a cognitive bias in which "people reach erroneous conclusions and make unfortunate choices but their incompetence robs them of the metacognitive ability to realize it."[1] The unskilled therefore suffer from illusory superiority, rating their own ability as above average, much higher than in actuality; by contrast, the highly skilled underrate their abilities, suffering from illusory inferiority. This leads to a perverse result where less competent people will rate their own ability higher than more competent people. It also explains why actual competence may weaken self-confidence because competent individuals falsely assume that others have an equivalent understanding. "Thus, the miscalibration of the incompetent stems from an error about the self, whereas the miscalibration of the highly competent stems from an error about others."[1] “ In the modern world the stupid are cocksure while the intelligent are full of doubt. ” — Bertrand Russell[2][3]
Interesting reference. However, you hardly know anything about me, so perhaps you have fallen prey to the Dunning-Kruger effect yourself. :-)
But while we're on the subject, let me continue.
Slash me to pieces for tooting my own horn. Actually, I only mentioned to "guru" bit in passing, as a short-hand for stating that I kinda know something about databases in high-demand environments, without having to spend an entire paragraph doing the same. If you want to pick it to death, go straight ahead and do so. Sheesh.
However, despite all of that, I do find the Dunning-Kruger reference interesting. I have been back and forth many times with assuming everyone has my level of understanding, and thinking I'm a stupid idiot despite evidence to the contrary. These days, I simply call an ace an ace. I know what I can do, I know what I am capable of, so why be shy about it? Do I know everything? No. I would never claim such. However, If I do know something, what's wrong with just being honest about it? Why is it some get offended at this? I put in the Blood, Sweat, Tears, and Years getting to where I am. Should I not be proud of that? What does modesty buy me?
I've had bloody enough of beating myself into the ground for this or that, and I refuse to do it anymore. I am an empiricist; I go by observations. And I have observed many others referring to myself as "guru", "genius", "brilliant", and what not. Quite frankly, I don't think all of those monikers are deserved. But then, I should give myself credit for what I have accomplished.
So sorry you are peeved. Actually, I'm not sorry that you are. That's your problem. Not mine.
That's why you get others to declare you a guru :)
They have, silly.
and realise that to easily comply with this law, you encrypt the filesystem underneath the database, not the data in the database itself.
Then again, anybody who declares themselves to be a guru at something probably is suffering from the Dunning–Kruger effect.
Others -- many others -- HAVE declared me a guru.
And do you have any idea the performance impact it would have on the database server to encrypt the underlying file system? You've obviously not worked with high-demand, high traffic websites before. You would totally fail at any major social networking website with that approach. You MIGHT get away with that approach in a high-read low-write scenario, but social websites tend to have a high-read high-write setup.
Coupled with issues of backup, maintenance, and what not, you'd send the system administrators screaming for your blood.
What do you think would happen to Facebook, say, if they had to encrypt all of their database servers -- and to say they have a thousand db servers is probably low-balling it. For sure it would destabilize their entire operation, and they would have to spend millions on equipment upgrades, probably go with hardware encryption options, and backups would be nightmarish, as they would have to be encrypted too.
Take my advice. Don't bother trying to get a job in the social networking arena.
don't think it's just that we can't "think out of the physics box". I'm saying that it is extremely unlikely that anything lies outside of that "physics box" that we'd (or any other civilization) find useful for interstellar space travel.
100 years ago we knew about the atom but no scientist at that time that could even begin to phantom the of power and energy it can generate. We knew about it, we saw it but it took a fairly long time before we discovered what we really could do with it.
It's not so hard to imagine that a hundred years from now we have discovered new properties and uses for things we already know about now.
Fairly long time? Not really. If anything, we learned pretty darn quickly what could be done with it, as Oppenheimer and buddies clearly demonstrated.
100 years from now? Yes, we'll find new and wondrous ways to manipulate atoms. We're doing so every day with nanotech and the like.
But fining ways to get around the speed of light implications for macro objects? Don't think so. The best we have today with regards to the fundamental nature of the universe are the family of superstring theories. And I have yet to hear any of those theoreticians announce anything like a possibility for superluminal travel for macro-sized objects.
That's why I've shifted my own focus from Cosmology/GR/QM to Complex Dynamical/Chaotic/Adaptive Systems and Fractals and the like. Much wonderful progress to be made there, even in our lifetimes!
Just today I used my SSN to access my forgotten username at fidelity.com. There's no question that Fidelity needs my SSN since my activities there have tax implications, so there's no way they haven't got my number stored somewhere in their databases. I have no problem with this.
More power to you. I begrudgingly make an exception for financial institutions, though I really shouldn't have to (and they give no choice these days, anyway). But for everyone else, they can take a hike if they think I will fess up my SSNO. Maybe they can pry from my fingernails.
Yes, I believe TrueCrypt is the best encryption software. TrueCrypt meets all the requirements, including avoiding vendor lock-in.
I dunno. I kinda like the AES encryption that comes free with Linux. Does everything TrueCrypt does for free -- and I get the source code to boot in case I get exceptionally paranoid about back doors, etc.
Firstly, your point about different territories with different rules is fundamentally flawed. Many places — all of Europe, for example — already have stronger data protection laws than most of the US. This causes no earth-shattering problem with compliance. Large companies keep the data they can't legally export within their European offices. Smaller companies just outsource things like payment collection to services that guarantee any personal data will be processed securely and not transferred outside of EU borders. They were going to outsource it anyway, so the only people who lose out are services that want to handle sensitive information but can't make the same guarantees as others about security, whose flawed business model just became obsolete.
If you are in, say, Great Britain, and Great Britain says you must encrypt all your data on your hard drive, you will have to deal with that, as you are under the direct jurisdiction of Great Britain. But if you are, say, running an Internet business in Montana, and Great Britain says you must deal with your data one way to do business with their citizens, and Massachusetts claims you must deal with your data a different way to do business with their residents, etc., what will you do? You will either go bust trying to comply with all the different and conflicting rules of ever region you do business with, or you run the risk of doing something illegal in a region you do not live in.
Stating that your data must be secured is one thing; stating how it is to be secured is another thing entirely.
I worked for a major online social network once, and we ran into the inane rules of the PCI, which micromanages business dealing with credit card data about how every workstation connected to the network must be managed, no matter how isolated the workstation from the credit card servers is. Things like idle times for screen savers (with password lockdown) being just, say, 5 minutes or so. It made doing software development from multiple computers unbearable as I had to continually keep typing in the stupid password every 5 minutes -- or giggle the mouse or touch the keyboard. It simply took away attention from my development efforts.
Being micromanaged by every region you wish to do e-commerce with is no picnic. If you are a mega-corporation, you can navigate those treacherous waters. If you're a small operation, a mom-and-pop, or otherwise less than a Fortune-1000 company, good luck.
I have been the victim of identity theft myself once, and I hear you on the annoyances of getting everything set straight again. But much of that pain comes from government agencies, corporate agencies, and others that simply refuse to believe that you've been duped. Perhaps some laws should be enacted in that regard to make it easier for the victim to recover.
But, truth being told, I can never trust law-makers to get it right. I can't trust law-enforcers to do the right thing, and I certainly don't trust politicians and all of their empty promises they do every election to "finally get it right".
If the civilization we discovered was 50 light-years away, it does us no good to lub something slow in their direction, as it would take many 10s of thousands of years to actually reach them! Imagine future generations on that planet not knowing why a planet-killer suddenly entered their stellar system. Assuming they could trace the origins back to our world, would they then hijack the device, reprogram it, and lub it back in our direction to reach us thousands of years later, where no one here would even know or can recall the device was ever built (or maybe from ancient records).
Relativistic weapons? Won't work, for the following reasons:
I think we, as humans, would choose to chat rather than nuke. But the latency on that communication channel would be ominous. It'd be 100 years before we'd get back a response.
And I am completely ruling out FTL, BTW. The only things moving away from us faster than light in our Universe are those things beyond our Universe's event horizon. Not going to happen in local space.
Baryonic Matter Sucks.
> Government's "solution" to all problems great and small is to put everyone at > gunpoint.
It's the only solution they have. Violence and the threat of violence is what government is all about.
> We may as well be dealing with mobsters.
You are.
And you have to wonder about a society that heavily depends on the threat of being shot as a means to get anything "done".
What this all means though is that the small startup/merchant/mom-and-pop Internet operations will find it more and more expensive to swim in these waters infested with little fiefdoms everywhere with delusions of hegemony.
What, you thought this law was passed for some purpose other than that? Laws like this serve two purposes: One, to be able to put a sound bite into ads and two is to help big companies keep small competitors out of the field.
Ha! Yep. And you're correct.
... and nothing I've seen to this time would even hint at the merest possibility of anything that could possibly make interstellar travel "cheap and affordable" my mere civilizations throughout the cosmos
Have you tried free-market economics? /ducks
Good one. [chuckle]