Mail 714 Thursday, February 23, 2012
This will have to be short shrift – most of the mail deserves more comment, but this is the best I can do as I fall behind…
"I do wonder about the proliferation of hypothetical constructs and intervening variables in physics."
You would almost think it was a hundred years ago ….
Port Ludlow, WA
FTL Neutrinos & All Things Dark In Physics
Don’t worry about the state of modern physics too much on the account of dark matter and dark energy. These things are at least replicably measurable entities. The moniker of "dark" is a frank admission of the physics community that they do not know what the stuff is, beyond the fact that dark matter must be matter of some kind, some where, as it has a gravitational influence and that dark energy must be energy of some sort because it causes the expansion of space-time to accelerate. There are many theories as to what each is, and they are indeed theories because they are each falsifiable through observation and experimental testing.
Where physics gets into a little trouble these days concerns theories of multiple universes, many of which are inferred from our current theories of the universe — general relativity theory and quantum field theory — but which are not falsifiable or experimentally testable. So, they cannot claim the mantel of "theory" but they are still discussed as such. The physics community needs to come clean and call them what they are, speculations. Speculations are important as they provide the seeds of future observation and experiment, but they should not be elevated to the status of evolution, relativity, or quantum field theory just because someone with a PhD dreamed them up.
Kevin L. Keegan
Ofer Lahav on dark energy
Subject: Ofer Lahav on dark energy
The head of the science programme at the Dark Energy Survey on the rapidly expanding universe and the future of dark-energy research
Dark energy, like the aether, is inferred from indirect observations. Some of those observations are recent and there hasn’t been a lot of though given to alternate views. We’ll see. Meanwhile the space telescopes tell us more…
re: UFO’s and Burkhard Heim
Dear Dr Pournelle,
I’m reading A Step Farther Out and just got through the chapter about UFO’s. Something struck me: you cite a remark by Robert wood that "these things are generally reported accompanied by a really overwhelming magnetic field".
A by-product of Burkhard Heim’s unified theory is that a strong enough (as in tens of thousands of Teslas) magnetic field cancels inertia. A common theme in UFO stories is their ability to move as if they had negligible inertia – seemingly unlimited acceleration , including "turning" at very sharp angles.
As you say, it’s all conjectures.
On a different tack, it’s often stated that special relativity is what prevents us from interstellar travel. Staying with Newton doesn’t really make things much better.
Assume only Newtonian physics apply and you want to travel from Earth to Alpha Centauri in a week.
Under constant acceleration/deceleration, you’ll have to generate and handle about 22,000 g’s.
Assuming you somehow manage to survive this, your speed at turning point will be about 220c, meaning your kinetic energy will be equivalent to about 24,000 times your mass.
Let’s be optimistic and assume you have near-perfect mass-energy conversion and know how to generate and control black holes so you can store all that mass in a small enough space.
You’d still have to accelerate all this at 22,000 g’s.
The math to compute how much reaction mass you’d need to achieve this is beyond my ability under a scenario in which you also convert mass to energy to accelerate your reaction mass, but I note that with a reactionless drive, you’d need about 5 PetaWatts to do it and get a 1,000t spaceship in orbit at Alpha Centauri. Using marine nuclear reactors, we’d need (using the only figure I could find, 54kg/kW, and that for the Savannah’s power plant) 270 billion tons of power plant to generate them.
So even if Einstein were wrong, to get the the closest star system in a week we’d still need to
1) learn how to survive 22,000 g’s
2) learn how to generate energy densities about 2 (based on rocket engines) -3 (based on nuclear plants) orders (the 1,000x kind of order) of magnitude higher than we’re currently able to.
It doesn’t sound really less far-fetched than the Alderson drive.
Nobody ever said it would be easy.
I like the Alderson Drive – I wrote the specs for it, sort of, as the input for Dan Alderson to work with – but I fear that the only way to the stars is generation ships. Those are possible.
An interesting article on how smartphones change healthcare outcomes:
I’m surprised it took the NY times long enough to figure this out. I’ve been using search engines to diagnose myself for over a decade; now I use WebMD. Before I go to the doctor, I do my research and my recommendations are often followed. Medicine is analysis, plain and simple. You use the same structured analytical techniques that you use in matters of statecraft. The only differences are vocabulary and the composition of the information — really.
Doctors must learn all sorts of vocabulary and rules, but the analytical framework is basically the same. What a concept? That’s what the modern education system tried to erase, but they failed with some of us. Doctors are expensive consultants who speak a different language and are authorized by law to do things I can’t, like write prescriptions. I only go to the doctor if I need antibiotics, etc. Else, you’re candy on a stick, lazy, or incompetent.
Joshua Jordan, KSC
Well, my professional career was in Operations Research, which is generalism par excellance. Gradually I learned less and less about more and more until…
Day of the Drone
I got a kick out of InvenSense’s disclaimer.
"InvenSense sensors should not be used or sold in the development, storing, production and utilization of any conventional or mass-destructive weapons or any other weapons or life-threatening applications as well as in any other life-critical applications including but not limited to medical equipment, transportation, aerospace and nuclear instruments, undersea equipment, power plant equipment, disaster prevention and crime prevention equipment."
While it is a precision accelerometer for -16G to +16G, it’s survivable at 10,000G shock tolerance. Doesn’t say what the temperature range for operation is (probably 50 to 100 degrees F?), nor what the tolerances were for electrical, magnetic or ionizing radiation interference or damage; although you can write to the company and ask for that information.
I wonder how durable these would be for a reusable space vehicle? At $150 a piece, you could easily have a light weight, multiple-redundancy system without worrying too much about one or two dying on a flight.
Michael D. Houst
I am told that the accuracy of these microgyro guidance systems requires correction by gps, and ICBM’s don’t do that. But drones get their position fixes from gps as well as inertial memory… It used to be that we talked about cruise missiles. Drones seem to be related…
Re: Drones or the do-it-yourself cruise missile
These pages have everything needed for an autopilot:
Parts are on the peg at the local MC for what amounts to pocket change.
For once, the electronics are cheaper than the airframe. Build one in your garage. One fellow in NZ pointed that out a few years ago and got in big legal trouble. See:
This guy has been messing about with pulse jets for quite awhile, so the results were somewhat predictable. On another part of the site, he shows where he built every kid’s dream machine, the jet-powered go-kart.
Just not sure why we haven’t seen any terrorist cruise missiles yet, maybe because it’s easier for the terrorists to program humans to do the job than microcontrollers.
I worked on inertial guidance systems at Wright Field from 1955 through 1958. Part of my job was to look for non-mechanical alternatives to rotating-mass gyros and moving-mass accelerometers. I came across a report on experiments by a Frenchman named Georges Sagnac. He had placed an interferometer on a ship and demonstrated that the interference fringes would shift if the ship were driven in a circle. That sounded like a lead to what I was supposed to work on. I found that the sensitivity of the interferometer depended on path length (longer path = more sensitivity) and on wavelength of the illumination used (shorter wavelength = more sensitivity). Knowing the maximum size that we could get away with in an airplane, I calculated the wavelength needed to get the sensitivity we required. It came out gamma rays. That was out. There are no mirrors for gamma rays, so you can’t make them follow a closed path. Good idea, but not feasible.
Years later, after I was long out of the inertial guidance business, I read an article in AVIATION WEEK about a laser gyro. The headline puzzled me. How do you make a gyro out of a laser? About two paragraphs into the story I realized they’d found a way to get a long path length, and make a Sagnac gyro work in either an airplane or a missile.
This is one of the tricks I learned to use in my later career as a technological forecaster. Ask "what’s missing" from a potential innovation, that makes it not feasible, then watch for something to provide that missing piece. The laser provided the missing piece for the Sagnac gyro.
Joseph P. Martino
Dandridge Cole said long ago that you can’t predict the future, but you can invent it. Of course your inventions will have effects you didn’t predict.
Gingrich definitely won the debate. Santorum will win some primaries and delegates, but not the nomination. I remembered that I didn’t support Santorum but couldn’t remember why. Ron Paul refreshed my memory while confirming my opinion that Santorum was the kind of kid who was always getting robbed of his lunch money.
More and more analysts are speculating about if not predicting a brokered convention. I believe that energy policy is the salient issue. If we don’t get energy policy right for a change, nothing else will matter. In spite of that infamous flirtation with Global Warming Theology posing with Pellossi on the couch, Gingrich is rational about energy policy. Santorum is also rational on energy policy and AGW. Ron Paul is also rational but would have a far too passive approach to energy policy. My fantasy is a brokered convention that nominates Governor Palin who is absolutely maniacal about energy policy. Obviously her activist approach to energy is policy is the result of the importance of oil production to Alaska, but she also understands how energy impacts the economy, foreign policy and national security. Alternatively, she could be the VP nominee and given authority over energy. If a President Paul, Romney or Gingrich reneged on such an agreement, she could seduce them. I have no doubt that the excitement of having sex with her would kill them then she would be President.
The Problem With Gingrich
I think the problem people have with Newt Gingrich is that he doesn’t care if people don’t like him, and he won’t apologize for having made someone mad. Everyone else will immediately rush out to apologize for and try to take back any statement that made someone feel mad. "Telling people who’ve spent their whole lives here that they have to leave is heartless! Um, wait, that doesn’t play well? Oh, well I didn’t *mean* it." Gingrich won’t play that game (or make that concession, if you want to see it that way.) And that’s why people get upset; not so much that he says things, but that he doesn’t pretend to feel sorry for having said them.
Mike T. Powers
"We thought they would support the other parties emerging from the womb of the revolution, but they didn’t."
Bacevich: ‘As Israel has discovered, once targeted assassination becomes your policy, the list of targets has a way of growing ever-longer.’
I am working on an essay about proscription lists. We seem to be legalizing them.
Spacecraft volume/mass calculator
This may interest you for both practical / fiction use; an online calculator for spacecraft volume and mass calculations.
"It ain’t fair? Hey pal, ‘fair’ is where you buy funnel cakes."
Norman Spinrad publishes rejected Star Trek script via Kindle Store.
Subj: Do we need more Solemn Excommunications?
Remember when I said the terrorists in Mumbai spoke a certain Hindu dialect? That made it very hard for me to believe that Muslim terrorists undertook those attacks; later I found evidence of certain outside intelligence agencies. As always, the discouragement fraternity had their baseless insults, accusations, denials, and disagreements. But, once more the truth rises to the top like the cream of the crop:
An Indian court on Saturday approved a request by prosecutors to charge an American citizen, David Coleman Headley, in connection with the 2008 terrorist attacks here, according to an official with the National Investigation Agency. The decision, which is the first step in seeking an extradition, sets up a possible confrontation between the United States and India.
Mr. Headley has confessed in the United States to playing a major role in the Mumbai attacks, which killed at least 163 people, but he testified against another man tried in the attack to avoid both the death penalty and extradition to India.
The plea deal has angered many Indians, already frustrated by the slow progress in the investigations into the brazen attack that unfolded over three days and shook this city. So far, only one person has been convicted in the case in India: the sole surviving gunman in the attacks, Ajmal Kasab, who has been sentenced to death.
The court on Saturday also approved charges against seven Pakistanis and another man in the United States, Tahawwur Rana. It was Mr. Rana whom Mr. Headley testified against in a United States court. Mr. Rana was eventually acquitted of helping to plot the Mumbai attacks, but he was found guilty of supporting plans to attack a Danish newspaper that published cartoons of the Prophet Muhammad.
Just because certain intelligence agencies were able to use Hindu operatives to pull this off does not mean the sponsor of those operations was a Hindu sponsor. It is quite possible to convince people to work against their interests, even if you are their greatest enemy. In fact, KGB operations revolve around these deceptions — consider Operation Trest. As time goes on, operations become more complex and this is not an accident. I don’t know why this is a shock to the average person.
Joshua Jordan, KSC
I have no comment because I have no reliable information.
Justice Ginsburg causes storm dissing the Constitution while abroad <http://dailycaller.com/2012/02/06/justice-ginsburg-causes-storm-dissing-the-constitution-while-abroad/>
Read more: http://dailycaller.com/2012/02/06/justice-ginsburg-causes-storm-dissing-the-constitution-while-abroad/#ixzz1mebxY5XE <http://dailycaller.com/2012/02/06/justice-ginsburg-causes-storm-dissing-the-constitution-while-abroad/#ixzz1mebxY5XE>
I missed this completely when it happened, and it’s not what I particularly want to hear from a member of the Supreme Court whose job is ensure this country follows the Constitution. It seems she would be inclined to change to meet her standards.
Well, it has always been the fancy that the Supreme Court decides what is the law of the land, but in fact they decided cases, and only those cases that the Congress allows them to decide. (There are some cases in which they have original jurisdiction according to the Constitution, but most cases come to them on appeal, and Congress sets that up.) Jefferson abolished a number of courts when he took office; he did not care for some of the judges Adams had appointed. The relation of the Court to the other two branches of government is more complex than is usually taught in school.