Slashdot Mirror

Indeed. It's also interesting to note that Einstein's original papers are eminently readable to the Layman, compared to the kind of papers we see in journals today. Perhaps that's due to the complexity of the mathematics now advanced at the bleeding edge, or perhaps it's because journals try to be even more economical with space than they used to be. I don't know.

... Cataclysmic events happen every now and then and causes extinctions and hardship on surviving organisms

Indeed, it appears that periodic cataclysmic events are required in order to keep evolution going.

We've seen several eras in Earth's history where life appears to "stagnate" at some level, proceeding with little-or-no change for long periods. The last of which was the "age of dinosaurs", which lasted 170 million years or so, depending on how you define the starting point. It ended with the Chicxulub impact.

We also see numerous examples of species which are largely unevolved; for example, ants have been around for 120 million years and one species of prehistoric ant is apparently still living in the Amazon. Coelacanths have been around in their present form for about 400 million years.

The overall impression is that life tends to "stagnate": once life evolves into an efficient survival mechanism, there's no pressure to evolve further. Evolution aims at being a better "fit" for the unchanging environment, but more complexity is simply not needed.

This is why I believe the Drake equation is overly optimistic. I think it omits the factor "fraction of star systems that experience occasional planetary meteor strikes". If we ever travel to another star, we're likely to find it teeming with life, but stagnated at some level.

This may be one factor (of possibly several) that explains the Fermi paradox.

The "doubling rate" identified in the article may be an artifact of Earth, and that's only if Genome complexity is even a reasonable measure to make. Lilies have 30x the genome size of humans - another explanation might be that genome complexity is related to genome size, which does not have much selection pressure. It's not a peer-reviewed paper.

They rely on the resonant frequency of atoms in metal vapors (Cesium or Rubidium), or the output of a hydrogen maser.

http://en.wikipedia.org/wiki/Atomic_clock

Radioactive decay is a chaotic process. So chaotic that it can be used as the basis for a random number generator. Just what you DON'T want in a precise time/frequency reference.

http://www.fourmilab.ch/hotbits/

Check out the exercise portion of The Hacker's Diet. You might also check out something like One Hundred Pushups. Or, take a walk at lunch time and during breaks.
--
JimFive

What is your Chi squared estimate applied to those results? That is to say, the probability that those results are due to chance?

I personally like the exercise plan in the Hacker's Diet. It's just a basic minimum level of exercise you should get per day.

Honestly, any particular scaling exercise routine would work well - the important thing is that you have something structured, that you can easily do without equipment, and that you have scheduled a block of time for. It's significantly easier to keep up an exercise routine if you have no excuses for not doing it, and "but I'd have to go to the gym" or "but I can't find my running shoes" end up being a lot harder to ignore than you'd think.

I personally like the exercise plan in the Hacker's Diet. It's just a basic minimum level of exercise you should get per day.

Honestly, any particular scaling exercise routine would work well - the important thing is that you have something structured, that you can easily do without equipment, and that you have scheduled a block of time for. It's significantly easier to keep up an exercise routine if you have no excuses for not doing it, and "but I'd have to go to the gym" or "but I can't find my running shoes" end up being a lot harder to ignore than you'd think.

Since you're worried about losing fitness, gaining weight, etc., -- which is great, most people don't start to think about it until after it becomes a problem -- and since you're an engineer, I suggest the first thing you should do is to begin measuring and tracking relevant stats. Anything worth doing is worth quantifying and plotting on graphs, of course :-)

Read (or skim) The Hacker's Diet. Whether or not you agree with its particular approach to weight management, it does a good job of instilling the idea that your body is just another piece of equipment that you can engineer. You can't redesign it, but you can set up negative feedback control loops that keep it in the configuration that you want it to be, and the first step is to measure and track so you have hard numbers that represent your state and trend.

This doesn't have to be difficult. In fact there are a lot of free on-line resources to make it very easy. Google will find you plenty more, but I'll give you the ones I use.

For overall weight and activity tracking I use http://fitbit.com/ It works best if you buy the $100 Fitbit pedometer/activity tracker and the $130 Aria Wifi-enabled scale (see how the website can be free, without ads?) but you can do it just by entering your numbers daily. Just weigh yourself every morning and take 15 seconds to record it (or if you have the Aria, just weigh yourself and the numbers show up on the web site). You can also track your exercise activities, your measurements (e.g. chest, belly, biceps, etc.) and whatever else you want, and the web site will give you nice graphs. If you get the Fitbit, or another pedometer whose measurements you'll have to enter manually, you'll have that measure of your activity level as well.

If you run, or cycle, etc., http://endomondo.com/ is a great tool for tracking those. Endomondo provides iOS and Android apps for your phone, and you can connect your Endomondo and Fitbit accounts, so when you go out for a run or a ride and track it with your phone, the activity automatically shows up on your Fitbit log. If you like you can also get a bluetooth heart rate monitor which the Endomondo app will use to log your heart rate.

Another key metric is food intake, but that's a lot more work. Fitbit provides food logging, but it sucks because it has a lousy food database. However http://myfitnesspal/ provides an excellent database which makes it easy to find whatever you eat, and the phone app includes a barcode scanner which makes it even easier for packaged foods. Oh and myfitnesspal integrates with Fitbit, too. Honestly, though, unless you're working towards a specific weight gain/loss goal, and you are pretty dedicated about it, logging your food is too much work.

Anyway, armed with measurements, plotted on charts, with trendlines you can see where you're at and where you're going, which enables you to see if there's something you need to be concerned about and to take charge if there is. If you want to make a change, just decide what you think would help and start doing it, then monitor your trends over a few weeks to see if it does. If not, or if not enough, tweak a bit more. Continue adjusting whatever knobs seem appropriate and observing the results until you are where you want to be -- or if maintaining is your goal, just keep doing what you're doing unless the trend lines show movement that you don't want.

The key to making the "measured lifestyle" work is making the measurements easy, automatic and habitual.

Oh, one other tool I've found helpful for goal achievement is http://beeminder.com./ It integrates with fitbit.com (and some other sites) and also provides SMS and/or e-mail reminders, as well as pretty graphs. Most importantly, though, Beeminder provides incentive. You can make a "pledge" to achieve a parti

Because if you update to the next version of Word or Excel, half of your macros break. The simplest-yet-complete rant on this I've seen is here: http://www.fourmilab.ch/hackdiet/comptoolsExcel.html

And by design, Word & Excel will ratchet themselves forward in versions (especially if you're working with clients). So why invest significant time in an infrastructure that is designed to break?

In car sales, that is called dynamic obsolescence.

Because if you update to the next version of Word or Excel, half of your macros break. The simplest-yet-complete rant on this I've seen is here: http://www.fourmilab.ch/hackdiet/comptoolsExcel.html

And by design, Word & Excel will ratchet themselves forward in versions (especially if you're working with clients). So why invest significant time in an infrastructure that is designed to break?

If we really seriously want to move from the expensive launch vehicle, expensive hardware optimization we are currently in, we probably need to do something like this.

That project is starting to sound like a boondoggle. Lots of PR and fundraising, no hardware. They have a contribution system, a mailing list, a Twitter feed, and press coverage. They've been blithering about this for two years now. But they haven't built so much as one single demo part.

We know what the Analytical Engine was supposed to do computationally. There's a simulator. It's a rather straightforward machine. It's roughly comparable to a programmable calculator of the 1970s. There are 1000 memory locations, each of which stores a 50-digit decimal number. These are separate from the program and data, which are on chains of punched cards. It can add, subtract, multiply, divide, shift, and compare, which is all you need.

Parts of the Analytical Engine have been built, and there's a working Difference Engine. So the components are understood.

There's no good reason for the 50-digit precision, and 1000 memory locations is too much for the compute power available (about 1 IPS). Like programmable calculators, 10 digits and 100 memory locations would have been enough for most problems. Babbage's own trial model of the "mill" (the ALU) has only 25 digits. Building a memory of 50,000 wheels about 3 inches in diameter means building something the size of a locomotive, most of which will just sit there. Trimming it down to 25 digits and 100 locations would make for a large desk-sized machine.

A question I once asked of the project was "how many part numbers"? That is, how many different parts are required? They didn't know. I suspect not that many. The existing model of the mill doesn't have a high part number count. The "store" (the memory unit) is inherently repetitive. Most of the parts can be die-cast and finish-machined, which is the most economical way to produce good metal parts in medium quantity. Many of the lever-type parts are cut from flat sheets of brass. Those you make with a CNC mill or a water jet cutter. 3D printing isn't really appropriate as a way to make brass parts, and making a plastic copy of the Analytical Engine would be rather tacky.

1.684Au or
156,537,715 miles
see
http://www.fourmilab.ch/cgi-bin/uncgi/Solar/

Nothing in this world happens by random - or have you heard of truly random number generator? No!

I have. Random occurs at the quantum level. http://www.fourmilab.ch/hotbits/ This site creates "hot bits"; truly random numbers. " HotBits are generated by timing successive pairs of radioactive decays detected by a Geiger-Müller tube interfaced to a computer."

Anyhow, this being /. what everyone here is *really* interested in finding is the Oh God! particle.

It's close cousin, the Oh-my-God particle has already already been found

Yahoo is currently running this Reuters article, in which we are told quite the assortment of lies about US spy agency operations. The spokesman expresses acute concern about respecting the privacy of US Citizens, and claims that US Spy Agencies do not spy on US Citizens except as absolutely needed for anti-terrorism operations. Wow, what a pack of lies!

I wish to, once again, remind readers about ECHELON, the UK/USA global signals intelligence system. We already know, from numerous leaks that have occurred over the years, that the USA intercepts all the electronic communications it can get at, regardless of whether or not it involves US citizens. We already know that the NSA avoids its prohibition on spying on US citizens by swapping data with non-US spy agencies that are allowed to spy on US citizens (e.g. MI6). So, please, don't be fooled by the outright lies and disinformation currently spewing from the marketing wing of US Cyber-command. They see everything, they examine everything.

Note that NSA et al can penetrate public key encryption via the QC system they have had online since the late 1990s, so any PKI-based cryptography tool is transparent to Five Eyes. I'd like to suggest one excellent truly open-source encryption tool which, while it is not perfect, probably renders your actual words opaque to ECHELON.

Thanks for the link.
I have a huge interest in weight loss, mainly because I used to be a bit overweight, (although never really "fat") and have struggled to keep my weight under control ever since I started trying to.

In fact, I've published an app for Android (https://play.google.com/store/apps/details?id=net.cachapa.libra) based on the Hacker's diet: http://www.fourmilab.ch/hackdiet

If you haven't done so, I really recommend you read it. If you have, then I'd be interested to hear your thoughts on how it compares with the link you posted.

The founder of Autodesk takes a similar approach. His guide is very detailed and motivating. I lost sixty pounds through simple calorie counting. (And then put it back on during some bad times last year, but at least it's under my control.)

http://www.fourmilab.ch/hackdiet/e4/

If you're seriously overweight (50-100+ pounds), this translates to all kinds of good news:

* The fatter you are, the more calories you burn. This really adds up at 100 pounds overweight. I was eating three hot, filling, satisfying meals a day and still losing two pounds per week.
* It's easy to get calorie counts for junk food and fast food -- just check the label or the web site! Eating poorly actually makes it easier to lose weight.
* Progress will be rapid and visible.

Most of the magazine articles and other popular material are written for neurotic skinny women who freak out about being 5-10 pounds overweight and want a simple answer to their self-image problems. Don't let them mislead you into looking for magic when the science is right in front of you. It really is this simple.

I can't mod because I commented above, but the post above is awesome! I also want to chime in that the food pyramid has been replaced by "my plate". This has been the case for a few years, now.

As for counting calories, it is the fundamental unit of measure for energy. I have shed a bit of weight and like to think of my body as a rational system. In the fact that the storage of fat and gains in girth are because I was eating too much energy than what I needed to survive so my body stored the weight. The Hacker's Diet gave me great insight as to how weight is 90% caloric intake, 5% genetics, and 5% exercise.

I'm wondering how this compares to The Hacker's Diet, which I found to be quite good.

Here ya go:
http://www.fourmilab.ch/hackdiet/ Written by the founder of autodesk. It's a bit dated, but still works wonders. He has an exercise routine in there that is nicely laddered and realistic. Coupled with the tracking spreadsheets and stuff, you can see all sorts of trends that allow you to tune in on where you need more work (whether diet or exercise).
-nB

I agree, i'm interested in the science, but i'm not willing to put the effort into micromanaging my entire life and and analyzing everything in detail.

A geeky friend of mine recently pointed me at the One Hundred Push-Ups program. It appeals to me because it's a webpage, it doesn't require anything complicated in the way of equipment or anything like that, it presents a simple and easy to understand plan with lots of numbers, and it takes place over a specific time period. You follow the plan, and the numbers keep going up till you reach your goal. (Assuming you manage to stick through to the end.) It might take more than six weeks if you have to take some do-overs, but it's definitely a finite period of time at the end of which you should see some definite improvement, something that really appeals to me. (I'm just starting week four myself right now.)

Another site i've used in the past is Calories Per Hour, particularly the BMR and RMR calculator. You can use it in conjunction with an exercise program, or just for setting up a diet plan. There's lots of numbers and math, which appeal to me as a geek, but at the end you have a nice simple number or two which tell you how much you can eat every day if you don't want to gain weight, and how much you can eat every day if you want to lose weight in a methodical and long term manner.

Of course on that note there's also The Hacker's Diet, which similarly takes the fairly straightforward approach that losing weight = consuming less calories than you burn.

You can argue a long time about paleo diet vs atkins diet vs south beach(?) or whatever other fad diet you've heard of, but in the end weight is just a matter of calories in vs calories out. If you want to lose weight you can reduce the calories going in or increase the calories going out. Certainly adjusting the kind of food you eat can make you healthier in other ways, but controlling the number of calories you eat is the first step. And if you start paying attention to the number of calories you eat you'll quickly discover that the healthier you eat the more you get to eat. Even just making the same food at home that you would have gotten at a fast food restaurant will save you a lot of calories than you can then spend on a snack or something. So instead of feeling like you _have_ to eat healthy to fit some particular diet you've decided to subject yourself to, you feel like you're getting rewarded for eating healthy.

Another classic along the same line is "The Hackers Diet". It's more about dieting and motivation than exercise, but well written and often funny (at least I thought so in the early 90's when I read it) http://www.fourmilab.ch/hackdiet/www/hackdiet.html

It's a great project, but I don't think it's really happening. The guy behind it is into PR, not cutting metal. "The project hopes to have a working machine before the 2030s."

There's a simulator for the Analytical Engine. It runs in a Java applet, and you can write and run programs. It's not that hard to program. The Analytical Engine is comparable to a low-end programmable calculator, without trig functions.

The machine itself isn't that complicated; just big. It's big because Babbage specified 1000 memory locations of 50 decimal digits each. So you need 50,000 memory wheels. That's all for data; programs are on cards. The "mill" part of the machine is roughly the complexity of a good mechanical desk calculator.

That's actually far too much memory for what the thing can do. Nobody seems to know why 50 digits, either. Babbage had figured out shifting, and understood scale factors, so it's not that he wanted to put the decimal point in some fixed place and work in fixed fractional mode.

If the thing were built with 100 memory locations of 10 digits each (a typical configuration for an 1980s programmable calculator), it would be equally capable, and 1/50th the size. That's enough capacity for navigational tables and astronomy. Built with full memory, it would be the size of a locomotive, and most of the memory would be idle. The extra memory wouldn't make it useful for bookkeeping or business; the I/O isn't there for that.

I wrote in and asked how many part numbers (different parts) the machine has, which gives a sense of how much manufacturing effort is required. There probably aren't that many; all 50,000 memory wheels will be identical, and most of the "mill" is repeats of a 1 digit mechanical adder. I didn't get an answer.

Somebody should model the machine in SolidWorks or Autodesk Inventor. (Or upgrade the mechanism support in Minecraft and let that crowd do it.)

Meh. I use hotbits, random numbers based on nuclear decay.

I'm re-reading The Hacker's Diet in another tab. Excellent article. Exercise is basically pointless when it comes to weight loss; twelve hours of bicycling full out to burn off one measly pound of fat. Who has the time for that? It's far easier to just not eat that extra pound in the first place.

I'm kind of disappointed. When I started watching the video, I thought someone had built this with moving parts in Minecraft But it's just a big collection of wired logic. It's not like you can see the parts move.

So hook up a VHDL compiler to the Redstone 2 Minecraft compiler. There are CPU designs available in VHDL. Generate a real CPU in Minecraft.

The cool CPU I'm waiting for is Babbage's Analytical Engine. The guy who says he's building a replica hasn't made much progress yet. Babbage's design had about a dozen instructions. But it was designed with 50-digit arithmetic (unclear why) and 100 memory locations (reasonable). The memory part would have been bulky, but the CPU is comparable to a mechanical desk calculator. It will be expensive to build, but as a CAD modeling job, not so bad, because it's mostly repeated instances of the same components.

Good stuff. Here's a pie-cutter for those who RTFL.

• Random.org provides random data generated by radio noise. You can get as much random data as you'd like. Gaming websites download their random data in 5MB chunks to use for card shuffles and dice rolls.
• HotBits is a similar idea, but uses radioactive decay instead of radio waves
• If you want to do it in house, you can do so with a smoke detector and a webcam. This was submitted to slashdot in 2006
• Finally, if you need a ton of random numbers, and they must be random, you can buy RNG hardware

What do i do? if I don't really care if it's random, I use the RPG from the programming language I'm using, or /dev/random. If I really, really care that it's random, I download a chunk of data off random.org, and either use that for the numbers, or use it to seed my RNG. For the most part, anything more than that is overkill.

While it may be the largest weapon deployed...

You be wanting the B41, at 25 megatons.

I suspect a far more interesting value for nuclear weapon ratings would be the effective blast radius, both as an airburst and at ground level. 9 megatons might be something that would wipe out an entire large metropolitan area, or it might be something that would just take out a city center. The difference is significant.

It is more efficient to use a bunch of "small" bombs than one monster one if you want to take out a city. This is described in detail in The Effects of Nuclear Weapons.

From the article:

"In the first instance the digitized documentation will be restricted to John Graham-Cumming and Doron Swade for the purposes of Plan 28 and in 2012 will be made available for research purposes and hopefully will have full public availability in due course."

That's a bit much for century-old documents. Fortunately, Plan 25 is open source and on line, along with a simulator in Java.

When just few percent of the launchpad mass gets into LEO, such (50+%) waste matters a lot. "The most reliable ... most frequently used launch vehicle in the world" (and among the least expensive ones, also in cost per kg) is a fully expendable rocket, semi-mass produced (on average over 30 per year; though there's a more mass-produced example in the very first widely used, large rocket; and who knows where we would be if OTRAG weren't cancelled for political reasons), and probably comfortably on its way towards a century of service (with how a new launchpad in Guiana is inaugurated right about now). Mass production, simplification, modularisation (of standard units) is what generally seems to do the trick in lowering costs of operations; few large, unique and overcomplicated units generally accomplishes quite the contrary.

Besides, capsules can be largely reusable as well. And don't forget how much they can do, and did, that STS-class vehicle cannot. Plus, why would you want humans to do experiments in a capsule? Space stations are for that ...for quite a bit longer than a puny one week (and if you insist, compare the length of "Soyuz strips" with those of the Shuttle in this timeline ...the first type looking there more like actual spaceships).

And most of the space station modules historically lifted, did so on an expendable launcher. In fact, there is some talk of retrofitting few in-storage "western part style" ISS modules with small orbital tugs, launching them on average medium launchers, and docking them autonomously like all Russian and some Japanese and European modules do - what will most likely end up being less expensive (including the R&D and manufacture of tugs!), less wasteful, than launching such modules on STS was! (which was "required" for many ISS modules only because they were specifically constructed that way, to give the Shuttle some purpose).
Think about it for a second - STS was among the three most powerful, by far, launchers in history (if not the most powerful at take off, too lazy to check). And yet, its payload capability was merely in the range of many medium expendable launchers. Proton, Ariane 5, Delta IV, Atlas V, Falcon, Long March, Angara, Rus. Pick one.

One shot of such launcher already gives comparable amounts of stuff to work with (of course you also need to launch crew on a separate launch or two, but it still ends up more economical and with much greater possibilities, much longer stay). And, if doing one launch of STS-scale rocket but without the waste of a glorified glider, you'd have few times more in just that one launch (Energia was a bit more sensible like that from the start - the Buran was just its payload; another one was an 80 ton space station modules, one being also at the core of their Mars mission spacecraft which Energia was to asemble; SLS will be also capable of such, it will represent this more sensible approach)

And if you want to bring some stuff back... well, capsules also lead in the amounts of recovered, valuable, purpose-specific, actually reused equipment (also scientific missions, including half of NASA experiments of such type, most during the Cold War; another type, and few more variants of just this one capsule here ...though the "Reentry" text of Foton, seemingly pasted over few arts, doesn't really make much sense and needs to be corr

Trek's end by John Walker (Autodesk John Walker, not the spy) addresses this also, with a twist: Trek's End full short story online

How about ultra high energy cosmic rays striking our atmosphere? The resulting collisions are far more energetic than any human experiment has so far achieved. They probably spit out a lot of stuff we haven't detected yet. http://www.fourmilab.ch/documents/OhMyGodParticle/

"Simple doesn't mean easy".

Anecdote in the Introduction: http://www.fourmilab.ch/hackdiet/e4/

I think you need a real random source (as some device counting radioactive decay) to create the passwords in a secure manner.

Done.

What now?

"Atlast" is an example of a forth that is intended for that kind of embedding. It's kind of showing its age, but it seems like it would be practical.

It's over at fourmilab, and is public domain.

That's dangerously close to "you need to spend (butt-loads of) money to save money" fallacy (why "routine space travel" dream should be of much significance, anyway? Also, I gave one or two replies nearby, no reason to repeat large parts of them)

The question isn't what's "doable", that's beside the point. Shuttle and Buran were doable, much easier in fact... and didn't deliver on any of its main points as advertised (it was supposed to be inexpensive and reliable, with fast turnaround, remember?). Set us back around 2 decades at least. Bled their space agencies dry for cash, caused cancellation of many great projects (many fantastic science missions, always the first to the axe...)

The question is what's practical. Spending half of GDP of the planet (or more...) isn't; no exploration in history operated on such basis.

And I didn't say "dumb payload" in the case of electromagnetic launcher, but "dumb rocket" - how it requires essentially the same tech as current rockets (yes, requires - at the least, there needs to be a massive kick at the apogee, otherwise what's being launched will deorbit at perigee), how it must (not just "most likely") be very similar to current launchers was the point; the "Pegasus" needs to be there, flying out of the end!
Again, not on a nice stationary platform (maybe with some simple multiplication of first stages (again, check Angara, from ~3 IIRC to 130+ tons in essentially single design) for the same effect as a megastructure), but moving on a high-g dynamic one... are you sure it will be inexpensive and reliable, with fast turnaround? Where have I heard that before...

All while the chemical "dumb rockets" are far from showing their full potential. We barely tried with what we know to significantly reduce costs - mass production (vs. skyrocketing (puns and all) costs with one-off massive projects). Maybe not necessarily to such or even such degree, but there's definitely a space for improvement. It's most likely not a coincidence that "the most reliable means of space travel" and "the most frequently used launch vehicle in the world" (plus one of most inexpensive ones) is about one and the same launch vehicle.

If space-time can "stretch" in the presence of a large amount of mess, then maybe it was crinkly in the first place? Presumably every atomic nucleus stretches a miniscule area of space-time around it, it's only really noticable to us as gravity when bundled together into planet sized objects.

There was guy who was .

There's one key word in that quote - "if". "There is no shortage of proposals for radically innovative space launch schemes that, if they worked..."

When we really seriously look at spaceplanes (say, HOTOL or Skylon studies), it turns out they aren't likely to end up any better (in best case scenario!) than "dumb rocket" using comparable technology, materials science ... on the level which we don't have yet, and which is required to make the spaceplane even borderline doable!

While, perhaps, we haven't utilized yet all the possibilities of dumb & simple approach, in some ways we are worse than first effort

What? Many approaches didn't envision the cooling systems that you mention. They still turn out to not give any returns, at best, when studied closer.

How most of the flight must happen outside the atmosphere (which dumb rocket knows, getting the hell out of it as quickly as possible - while spaceplane you envisioned lingers), the basics of rocket equation / how spaceplane wastes lots of payload fraction for airframe - probably means things won't change significantly for a long time, except for some niche uses (like in this case, military)

Remember how the Shuttle was advertised? How it delivers? What actually turns out to be cheapest per launch? (and we barely tried mass production - basically only with very first widely used launcher)

Look at those airplanes (/. & unicode links) from "our" times, as envisioned ~130 years ago (and probably influenced by rapid advances in (sub?)marine technology) - we can build them! (take a Harrier, get rid of the wings and canopy). But strangely, we have settled on something quite different in concept, also when it comes to the mode of operation. Spaceplanes are a dream from scifi of the '40s and '50s (a lot of Shuttle designers probably raised on it...), fueled by rapid advances in airplane technology. But they are a bit analogous to flying boats - and not many those around nowadays (except, again, for very niche uses)

They don't have to be that complex - http://en.wikipedia.org/wiki/OTRAG (yes, this one perhaps goes too far - but consider how liquid ones are far easier to mass-produce (they are inert during manufacture & transport); the only mass produced large booster, V-2, was liquid)

Einstein, Heisenberg, and Tipler
by John Walker
9th August 1995

Einstein seized the moment, “Look, Old One”, he said, “physics is local. You made it that way; I figured it out. But why is there that spooky action-at-a-distance nonlocality in quantum mechanics?”

God chuckled. Even experiencing all of spacetime at once, such events were rare. “Albert, your greatest talent has always been not finding the right answer—anybody could do that—but asking the right question. Your generation learned physics assuming I was a great watchmaker; you destroyed that notion, but most of you died off before it became evident what I was. I create abstract systems from pure information, Albert. I'm a programmer.

“Quantum nonlocality is a bug.”

Energia would be probably nice, yes, in launches without Buran (but still probably not very cost effective due to scale and rarity of the launches). HOTOL was apparently dropped when it became clear that a rocket using the same technological advances would be at least equally effective (but much less complex). And you would want to up the size of the Shuttle?

An orbital launcher flies most of its mission outside the atmosphere. Most of its mass is reaction mass. That, together with what the rocket equation is, probably means a pure rocket will be able, for a long time, to better use technological advances necessary to make a true spaceplane even barely possible.

But perhaps such advances are not even the best way, perhaps simple mass-production would be better. We had a test run, with the first widely used rocket; too bad the orbital effort in such style was killed.

Light has *momentum*. Technically, it's just p = hf. I'm not sure why you need to reference a textbook, but you seem to go about everything in bizarre and unproductive ways. [ShakaUVM]

Because that's from early 1900's quantum theory, not classical electrodynamics. My point is that even in the 1800's, it should've been clear that light has momentum and thus inertia just by examining Maxwell's equations.

... I only consider objects with mass to have inertia, as a massless object cannot have an inertial reference frame that makes any sense. A number of people agree with me. For example, Greene equates inertia with particles with mass.

That's an interesting definition; I've never heard of it before. Like Einstein, I prefer to call "E/c^2" the "inertia" of light because that's the conceptual breakthrough which resolved the original pesky factor of 4/3 that kept appearing in Lorentz's derivation of "E=mc^2":

And because the em-mass depends on the em-energy, the formula for the energy-mass-relation given by Thomson (1893) and Wien (1900) was m = (4 / 3)E / c2 (Abraham and Lorentz used similar expressions). Wien stated, that if it is assumed that gravitation is an electromagnetic effect too, then there has to be a proportionality between em-energy, inertial mass and gravitational mass. However, it was not recognized that energy can transport inertia from one body to another and that mass can be converted into energy, which was explained by Einstein's mass-energy equivalence.

The idea of an electromagnetic nature of matter had to be given up, however, in the course of the development of relativistic mechanics. Abraham (1904) argued (as described in the preceding section #Lorentz transformation), that non-electrical binding forces were necessary within Lorentz's electrons model. But Abraham also noted that different results occurred, dependent on whether the em-mass is calculated from the energy or from the momentum. To solve those problems, Poincaré in 1905[A 8] and 1906[A 9] introduced some sort of pressure of non-electrical nature, which contributes the amount (1 / 3)E / c2 to the energy of the bodies, and therefore explains the 4/3-factor in the expression for the electromagnetic mass-energy relation.

It also happens to explain the paradox discovered by Poincare regarding conservation of momentum in different frames when using Lorentz transformations to transform between inertial reference frames.

In other words, the reason Einstein is a household name but Lorentz is known only to scientists can be traced back to the fact that Einstein recognized that light has inertia.

You're quite wrong that it was an expected result - read, and look at the number of times they kept trying to get the experiment to "succeed".

First, I just said that as the story goes, Einstein based special relativity on his daydreams and pre-existing problems with the aether. That's the official story, but I find it hard to believe that Einstein really didn't think about the Michelson-Morley experiment during this process. However, that's what Einstein claimed and the story is at least remotely plausible given his stratospheric genius.

Second, I didn't say Michelson and Morley expected it. I just said Einstein claimed to not find it surprising or informative in his development of special relativity, and that aether timeline I linked should provide convincing evidence that the aether had already been shown to be logically inconsistent long before Michelson and Morley started their w

There's an Analytical Engine emulator available. It's a Java applet.

There's no fundamental obstacle to making a working replica, other than money.

The same patent bit AutoCAD

I'm not sure if we can expect much good from "new, revolutionary launch system" - wasn't Shuttle supposed to be one already? (inexpensive, too...)

So you are honestly implying that just because we tried an experimental and non-traditional launch system once and it didn't work out as well as hoped, we should never do it again? IMHO, research and development into alternative launch vehicles is one of the main things of what NASA should be doing. The private sector as a whole is very good at, and usually interested in, incrementally improving existing aerospace technology, not so much (especially the interest part) for very novel and/or unproven things. However, because every, or even a majority of programs, don't have to be financially successful NASA is freer to do ambitious R&D.

Bigelow Aerospace is a good example of how the public-private dynamic should work, their Genesis I and II are remarkable achievements and will likely be the foundation of future commercially owned and operated orbital craft. However, despite their commendable work and accomplishments they didn't start from square one. Instead, they built on years of NASA research on expandable spacecraft, the most recent and important being the TransHab program of the 1990's which was promising but specifically killed by Congress in 2000. I don't think even a wealthy and self-described space enthusiast like Robert Bigelow would have risked starting a company in 1998 whose main product will be inflatable space stations without the existing groundwork provided by NASA.

Especially if we have an almost 70-year old example of what can be accomplished by proper design, production and launch campaign (yes, orbit requires minimum an order of magnitude more work from a rocket, but manufacturing/etc. are less dissimilar)

The fact that the V-2s were sub-orbital isn't the most important difference. IMHO what makes this a faulty analogy is that the conditions of their production would be almost entirely different from the manufacturing conditions used for any modern launch system in the Western World, or at least I hope so (pay special attention to the blue box half-way down). The V-2s were built by what was essentially slave labor! Both skilled and unskilled workers from Nazi occupied territories forced to work over ten hours per day only receiving very basic shelter and clothing, with subsistence level rations (at best). Also worker safety was practically non-existent and since some of these workers were considered "sub-human" their dieing was sometimes not even considered a bad thing! Big surprise that when you treat your workers like chattel many of your per-unit costs are negligible...

I'm not sure if we can expect much good from "new, revolutionary launch system" - wasn't Shuttle supposed to be one already? (inexpensive, too...)

Especially if we have an almost 70-year old example of what can be accomplished by proper design, production and launch campaign (yes, orbit requires minimum an order of magnitude more work from a rocket, but manufacturing/etc. are less dissimilar)

It may be and md5 hash though the value of the hash is not their mission statment http://i26.tinypic.com/5mesra.png made using fourmilab's md5 tool http://www.fourmilab.ch/md5/

also try entering the mission statement in these online md5 hash tools:
http://www.md5hashgenerator.com/index.php
http://www.miraclesalad.com/webtools/md5.php

I'm sure you can find others that generate the same results as the ones listed above that again produce the result 98e1259d50ef66ddf1c6f443f8a86ec5 and not 9ec4c12949a4f31474f299058ce2b22a

Don't believe everything you read on the net without finding out whether or not it's true yourself =)