Today I decided to buy a toy replica of the 11th Doctor’s sonic screwdriver and was amused at what else it suggested I buy:
Then again…bow ties are cool.
"We should not be afraid to speculate. But we should be careful to distinguish speculation from fact."
For those interested here are the equations for the black hole generator. The three main pieces of information we are interested is the black hole’s mass M (in kilograms), the power output P (in Watts), and the time it will take to evaporate (basically, the safety margin) T (in seconds). If you know one, it is possible to obtain the other two:
P = 3.563 x 10^32 / M^2 = 6.838 x 10^21 / T ^ (2/3)
T = 8.407 x 10^-17 * M^3 = 5.654 x 10^32 / P ^ (3/2)
M = 2.283 x 10^5 * T ^ (1/3) = 1.888 x 10^16 / P ^ (1/2)
Rechecking the numbers it appears I actually made errors in calculating the black hole’s parameters in the previous post, so I went back and corrected them.
For the past few days I’ve been kicking around the idea of using a black hole as a power generator. It seems counter-intuitive: a black hole absorbs all matter, right? How would one use it to create power? The answer lies in the fact that all black holes emit what is called Hawking Radiation.
In 1974, Steven Hawking showed that black holes have temperature due to quantum effects, and anything with a temperature above absolute zero will create black-body radiation. This radiation obviously has energy, which comes from the mass of the black hole itself (the details aren’t particularly important, only the big picture). Essentially, black holes will slowly evaporate and thus shrink. Even stranger, as they get smaller, black holes will emit more and more radiation until they have no more mass left and completely disappear.
So, what if we were to construct a black hole and harness this energy as it is emitted? We capture it (more on this in a bit), build, say, power cells around it, use it as a power plant? Now obviously, it would be bad to let the black hole evaporate completely as the power output increases enormously as it shrinks. In a practical sense, the black hole “goes critical” and explodes. So…what if we continually feed it with matter to keep it at a relatively “tame” level? Say we have our black hole, and we’ve tuned it to produce, say, 10 TeraWatts of power, enough to power the Earth. It’s mass would be (if my math skillz haven’t failed me) about
1.9 million 6 million tons and be about one ten-millionth of a billionth two millionths of a billionth (2 x 10^-15) of a centimeter in diameter. 10 TeraWatts means it will lose roughly 0.11 gram per second in radiation and every year it will lose about 3500 kg in mass. If we continually input matter at that same rate, the black hole will remain stable and continually output 10 TeraWatts.
The reason this is so intriguing is because the conversion rate is (theoretically) 100% efficient. We put a kilogram of matter into the black hole, we’ll get (eventually) a kilogram of mass-energy back out, and the black hole will be exactly the same as when we began. Compare this to fusion where the efficiency is only around 0.7%. That’s a huge difference! Even better, any matter at all will work, not just hydrogen and helium. Elements that are past iron on the periodic table are useless for fusion, but work just fine with black hole generator.
Creating such a black hole is left as an exercise to the reader, but here’s how you hold it. Well you actually don’t have to “hold” it. If you’re building this power generator in space, you can just let the black hole freely orbit the Sun or the Earth and construct your power collectors around it, but it wouldn’t be very mobile. If you actually wanted to take it with you, you could initially feed the black hole with some amount of electrically-charged matter. If a black hole swallows an electron, the black hole itself will then have a negative charge. You can use this fact to electrostatically levitate the black hole, like how if you stack two magnets on a stick with the same poles pointing towards each other, one will stay hovering above the other in mid-air. Neat huh? One just needs to continually input charged particles to keep the charge on it.
Even the threat of the black hole “going critical” is literally very remote. If left to physics alone our hypothetical 6-million-ton black hole won’t actually explode for over
18,000 568,000 years.
Anyway, looking around the web, it seems as though someone has already written a paper on this. I suppose I’ll take it as a good sign that my own musings are paper-worthy material (though in their paper they use the black hole to power a space ship), just the rigor is lacking.
A Dyson Sphere is a massive solar power collector that entirely encloses. I used the concept in my series Alien Civilizations as a means to capture all the outpouring energy from all the stars in the universe.
The concept I used is likely the most feasible: a swarm of independently orbiting collectors, each with its own orbit, all controlled by computer system to keep them from crashing into each other. This doesn’t require any undiscovered materials or technology, and we could probably begin building such a structure today. The only problem is the sheer amount of mass that would have to be transformed and transported, required enormous space-based infrastructure and manufacturing capabilities.
But there’s another design that is far less feasible, but more interesting: a single solid shell, 2 AU in diameter, used as a huge space habitat. This has a number of problems, not the least of which is that it is unstable.
Newton’s Shell Theorem states that in any hollow uniform sphere, the net gravitational force in any location is zero. Simply put, if you were inside a hollow sphere, you would not “fall” in any particular direction due to gravity. At all points, the gravitational force from all parts of sphere cancel each other out. The problem is: how you keep such a thing centered on the Sun?
One obvious answer is attitude thrusters, but that seems a bit drastic, and energy intensive. My idea is, well, what if it isn’t a uniform sphere? What if we specifically constructed the Dyson Sphere so that it was more massive on one side? Could we set up some sort of psuedo-orbital situation from that?
Second is how you go about constructing it. Half a sphere is also very unstable, but is an inevitable stage in construction. Or it is? Instead, what if we were to first build the equator-region in inertial orbit? What if we start by building a giant ring that it orbiting the Sun? Then, we start building towards the poles, keeping the center of mass within the equatorial plane at all times?
Last is the fact that the Dyson Sphere will heat up. Now because the Dyson Sphere is so huge, it actually won’t get as hot as the Sun. In fact, we can calculate where, at thermal equilibrium, the Dyson Sphere will be a comfortable 72 degrees F. In order for it to be that way, a Dyson Sphere should be around 265 million km in radius, or about 1.77 AUs. This is quite a bit larger than the orbit of Earth, but that it because all parts of the Sphere are in full daylight constantly, whereas half the Earth is always in shadow. Also, the spherical shape of the Earth spreads out the incoming heat from the Sun onto a larger area (specifically twice as large).
Of course, the main challenge is finding a material that could withstand such enormous structural stresses, and finding enough matter to actually build it. For those, I have no idea. The amount of usable material in the solar system is probably not enough.
Well, but if we do overcome those obstacles, maybe we could build one. It would certainly be a sight to see. Or not. Considering the sphere would completely cover the Sun, it would only appear as a giant black disk from outside. How boring.
Back on The Other Blog, I once wrote about how my company (Stater Bros.) could save millions a year by using an automated ordering system, and how it would also increase revenue at the same time. Now it appears that I will get my chance to inform my corporate masters employers about my idea. There are forms at work that they’ve distributed around declaring a “War on Waste” which basically is asking for ideas from anyone about how the company might cut wasteful spending. If you submit one you get a little pin and if your idea is selected, you basically get a pat on the back. But, it might help my visibility in the long run.
Also, I have decided that I am finally going to send off a short story somewhere. I don’t know where yet, but I’ve written one about scientists at SETI discovering intelligent life via radio technology (I know I wrote earlier how unlikely that is, but, hey, it’s just a story). Because aliens, if they do exist, will likely have been around for millions or billions of years, I figure they’ll likely be concerned about the “galactic ecology”, meaning keeping their own growth and energy consumption down, so they don’t quickly use up their resources and cause themselves to go extinct. Civilizations that last that long don’t get that way by ignoring environmental limits. But, they’ll also maybe not be total destroyers, believing that other alien species have the right to exist, just as they do. It’s a tricky situation, allowing new members in pool of limited resources. The message recieved by the SETI scientists, once deciphered, basically turns out to be a “Oh hey, welcome to the universe, we’re glad you’re here, but there are some rules you have to abide by, or else…”
Damn, I just gave away the ending. Oh well, it’s not like anyone actually reads my blog so no harm done. And if I do get readers by people reading my short story, they’ll already know the ending anyway.
Today is March 14th, and you know what that means: it’s Pi Day! You see because pi is (approximately) 3.14. And today’s date is 3/14. And…well that’s it, really. I’m looking forward to 2015, when we will be able to write the date 3/14/15, which is the first four digits of pi. And on that day, at 9:26:53 it will be super-duper Pi Second, because pi is 3.141592653… Although rounding purists will probably prefer 9:26:54 because the next digit after the last 3 is a 5. Heh, what nerds <snort>!
Anyway, today is double special for me. Why? It’s my birthday! Well, ok, it’s not my birthday, but it is the birthday of my character in my semi-autobiographical novel Alien Life. It’s about an extraterrestrial who’s come to Earth to study human culture and technology. A sort of intergalactic anthropologist. He, that is to say I, or Alien!Arik Rice, was born on this day, at least on the human calendar.
So, how old is the little tyke? Well it starts with a 1. And ends with a 2. And it’s not 12.
He’s 16,102 years old, born in the year 14,094 B.C.E. Yes, I’m he’s older than human civilization itself! All because of mind upload and taking care to avoid unnecessary risks, although uploaded people in his civilization are practically indestructible, so even relatively large risks are not hazardous. That’s what you get when your civilization is over a billion years old.
It’s been about three weeks since I last updated, so I figured it might be about time to let my adoring public know that I am still alive. Actually, I’ve been sick the past couple weeks. It’s getting pretty annoying. Plus I’ve been busy with school and work.
What I’ve also been doing is working on my game that I invented. I was lucky enough to get a chance to play Robert Kiyosaki’s game Cashflow 101 a while back, without having to shell out an outrageous $200 (I will never pay $200 for a boardgame. Even if it is a “pedagogical tool”. Especially from someone who’s only success at making money is…telling people how to make money. Yeah). Anyway, I thought it would be cool to have my own copy, but I noticed a few flaws and places where it could be improved. It’s been hardwork, but I’m nearly done now, and have retitled it “It’s Just Business!”. I’d sell it, but then I’d probably get, you know, sued. Although at this point it’s different enough I don’t know if they’d actually have a case.
Also, I’ve been working on a new novel, one which I am so excited about it may end up being my first one. It’s about a group of about four hundred fifty people who get stranded back in time in the late Cretaceous period, shortly before the extinction of the dinosaurs. Sounds like a pretext for a Jurassic Park-type story, right? But Jurassic Parkhas been done, and I hate doing cliched, predictable ideas. No, the real story is about their situation and really about what possible temporal paradoxes that might arise because of their presence there. Are they changing the future? If so, are they possibly erasing the future evolution of the human race, and thus their own existence? If not, why is there no evidence of human civilization at the time of the dinosaurs? Are they really in some parallel dimension, a split timeline, or something else entirely? And what about that asteroid due to hit soon?
In any event, I’m going to try to stay on top of this blog as it is the “public face” of my life.