View 837 Monday, August 04, 2014
“Transparency and the rule of law will be the touchstones of this presidency.”
President Barack Obama, January 31, 2009
Karl Lembke is a chemical engineer with the LA Department of Water and Power, and works in the quality department. He is also a one of the leaders of the Los Angeles Science Fantasy Society and thus an old friend. He sends this
Posted by Chad Orzel on August 4, 2014
I’ve gotten a few queries about this “Impossible space drive” thing that has space enthusiasts all a-twitter. This supposedly generates thrust through the interaction of an RF cavity with a “quantum vacuum virtual plasma,” which is certainly a collection of four words that turn up in physics papers. An experiment at a NASA lab has apparently tested a couple of these gadgets, and claimed to see thrust being produced. Which has a lot of people booking tickets on the Mars mission that this supposedly enables.
Most physicists I know have reacted to this with some linear combination of “heavy sigh” and “eye roll.” The proposed mechanism doesn’t really make any sense, and more importantly, even in the free abstract for their conference talk they state that both the configuration of the device that was supposed to produce thrust and the “null” version that was not supposed to produce thrust gave basically the same result. As Tom notes, this is mind-boggling, and John Baez goes into more detail, including a link to the paper.
The paper itself is kind of a strange read, like it was put together by a committee containing a mix of responsible, hard-headed engineers and wild-eyed enthusiasts. The experimental procedure and results sections are very sober and pretty clear that this is not a meaningful test of anything, but then there’s a whole section planning missions to Mars with scaled-up versions of the technology. Which sort of suggests that this was a test run by some career engineers at the insistence of an enthusiast who’s highly-placed enough to make them do tests and write up stuff that they find kind of dubious. But that’s just speculation on my part.
The only thing I have to add to this discussion is a quick mention of why this is likely to have gone wrong. The core technique described in the report is a “torsion pendulum.” This is a technique for measuring tiny forces that dates back to the days of the singularly odd Henry Cavendish, and is still one of the principal techniques for measuring the force of gravity. The basic idea is to hang your test system from a thin wire, balanced at one end of a barbell-like arm, then do something that makes the barbell twist. The amount of twist in the wire will then tell you how much force was produced.
The basic technique has a long and distinguished history. It’s also notoriously finicky, which is why there’s still a lot of uncertainty and debate about gravity measurements. From stuff quoted by Baez, this seems to be the first use of the NASA lab’s torsion pendulum apparatus, which is not terribly promising. There are zillions of ways this could go wrong, and you’re not going to account for all of them the first time out of the gate.
To give you an idea of what’s involved, one of the very best groups in the world at doing this sort of measurement is the “Eöt-Wash Group” at the University of Washington, whose short-range tests of Newton’s inverse-square law provide the extremely shiny photograph in the “featured image” up at the top of this post. I’ve seen numerous talks by these guys, who are awesome, and in many of them they show a photograph of the lab, which contains a big shiny vacuum chamber and set of magnetic shield at one side of the room, and a knee-high stack of lead bricks right in the middle of the floor. That’s not because some grad student got tired before getting all the lead back to the storage room– the pile is placed very deliberately to counter the gravitational attraction of a large hill behind the physics building there.
That’s the level of perturbation you need to account for when you’re doing these sorts of experiments right. Now, the Eöt-Wash crew are looking for much smaller forces than the rocket scientists in Houston, and Houston is pretty flat, anyway, so they may not need to worry about carefully placing lead bricks. But there are dozens of tiny perturbations that are really hard to sort out– the report specifically mentions vibrations caused by waves in the ocean a few miles away, and if they’re seeing that, they’re going to be bothered by a lot of other stuff. This isn’t something you’re going to sort out in the roughly one week of testing that they actually did.
So, yeah, don’t go booking yourself a ticket to Mars because of this story. It’s almost certainly an experimental error of some sort, most likely a thermal air current due to uneven heating. Which is a failure mode with a long and distinguished history– Cavendish himself noted in 1798 that an experimenter standing near the case could drive air currents that would deflect the pendulum, so he put the entire apparatus in a shed, and took his readings with a telescope. And in his final set of data, he found that he needed to account for the difference in heating and cooling rates between his metal test masses and the wood and glass of the case.
The good news is that there’s enough sober and practical content in the report to suggest that somebody there will eventually do this right. At which time the effect will probably disappear– it’s already a few orders of magnitude smaller than an earlier claim, according to the space.com story linked above. Removing air currents as an issue (which they can do, but didn’t because they were using cheap RF amplifiers that couldn’t handle vacuum) will probably wipe it out completely.
(Also, my forthcoming book has a big section on Cavendish. But that’s not out until December…)
“As Wired.co.uk reported, this happened last year when a Chinese team built its own EmDrive and confirmed that it produced 720 mN (about 72 grams) of thrust, enough for a practical satellite thruster.”
1 newton [N] = 7.23301385120989 pound foot/second² [lb·ft/s²]
I assume 72 grams thrust is 72/1000 x 2.2 pounds or about .16 pounds of thrust with about 2 kilowatts of power. One presumes that more power would produce more thrust, but even if it couldn’t that 0.16 pounds of thrust is plenty enough to measure with a gravity swing. Torsion pendulum measurements – as used in the Eotvos Experiment that showed that gravitational mass and inertial mass are equal to some seven decimal places – are needed to detect really tiny forces, but they are enormously sensitive, and require a lot of work to compensate for various outside events, as indicated in Orzel’s text.
Hang the apparatus on a swing; 720mNs will be more than enough to cause it to hang measurably off vertical. When it comes to rest off vertical you know you’ve got something, and it will be a lot easier to rule out other errors. A torsion pendulum is far too sensitive for this work.
Karl also defends his DWP colleagues:
As I suspected, the water trunkline break in Westwood was a major item in the news. (I first heard about it while I was in Woodland Hills, hooked up to an apheresis machine.) I haven’t seen anything beyond your initial observation, so i thought I’d provide a bit of insider perspective.
There was a 60 foot geyser on Sunset near UCLA, where a water main broke. This being Los Angeles, aka Detroit Southwest, it took the DWP an hour to get someone out there, and while it’s no longer a geyser, the water is – ha. As I write this, the radio announces it has stopped. It started at 1530 this afternoon. Flooded the lower decks of several parking structures. Cars lost. Los Angeles has highly paid city workers, but not a lot of city work gets done.
While I can’t speak for most of the city workers, I’ll offer a couple of points about the DWP response time.
1) Traffic into and out of that part of town that time of day is generally awful. Even in the morning hours, it can take me an hour to get from the DWP building to that precise area, just south of a number of designated sample points for the distribution system. In the late afternoon, it’s always worth the extra time spent going around that area.
To be sure, DWP crews would not be responding from downtown Los Angeles, but rather from one of the maintenance yards. The nearest such yard is the West Los Angeles yard, not far from the West Los Angeles Kaiser hospital. From there, there aren’t many routes to that part of Sunset Blvd that don’t involve driving along Sunset. Looking at a map, the best approach might be to head over to Westwood Blvd and then find a way around the UCLA campus. Another possibility would be to go through Bel-Air: Head north of Sunset on Stone Canyon, and then cut across Bellagio to where it joins Sunset, in about the right area.
But this is being done with 20/20 hindsight and could still have led crews into an impenetrable mess on the ground. (I went over and looked in the gate book. It was open to the detail showing the trunkline going past Stone Canyon. If you wanted to try approaching through Bel-Air, you would head north on either Bellagio or on Bel-Air Road. So much for 20/20 hindsight.)
2) Once a crew has arrived, where are the valves? The gate book shows the nearest valve for the 36" trunkline is over by Copa Del Oro Road, between Stone Canyon and Bel-Air. As they say in the travel ads, "getting there is half the fun." Hopefully, the valve itself isn’t under water. That might require locating the next valve upstream.
3) The water main involved was a 36-inch trunkline, right where it splits into a 36-inch and a 30-inch trunkline. This would be a part under a fair amount of stress from the flow of water. Since it broke, it would seem to follow that we want to avoid further stress by shutting off the water very rapidly. Certainly, the last thing you want is water hammer sending shock waves back up the trunk line and splitting every weld, joint, and bend until the force of the shock wave was spent.
I suspect, when all is said and done, the DWP response to the break will turn out to have been at least as fast as could have been expected.
Another topic that will be discussed (and already is among the talking heads on local radio) is why we have century-old water mains in the city. Shouldn’t we be replacing them?
Well, we are. It takes a while for each main, and has to be done around the other improvements we’re doing, such as bypassing reservoirs that no longer meet stricter environmental and health regulations. Or we could shut down water service to the entire city for half a decade and renovate it from top to bottom.
The Wheel of the Year <http://www.amazon.com/Wheel-Year-ebook/dp/B004MPRET4/> : Now available on Amazon Kindle
The Official Manual for Spice Cadets <http://www.amazon.com/Official-Manual-Spice-Cadets-ebook/dp/B004P8JJUU> : Now available on Amazon Kindle
Yet another illustration of why I don’t usually comment on breaking news.
I am told that Los Angeles is on a three hundred year pipe replacement schedule, and that changing to a two hundred year cycle would be prohibitively expensive; also that old man Mulholland, who headed DWP in the days when the pipes were being laid, kept the only accurate copies of all the plans and maps, and when he was dismissed in disgrace took them with him; but that may be a rumor. In any event they are still cleaning up the Sunset Geyser and sinkhole.
Tobacco and Ebola
Scientists stumble across the obvious treatment for Ebola: tobacco <http://www.nbcnews.com/health/health-news/tobacco-plants-plus-antibodies-equal-possible-treatment-ebola-f6C10963179>
Wed, 21 Aug 2013 20:08 CDT
A cocktail of antibodies cooked up in tobacco plants may provide an emergency treatment for Ebola virus, one of the deadliest viruses known, researchers reported Wednesday.
The treatment provides 100 percent protection to monkeys when given right after exposure. But it also helps even after symptoms develop, the researchers report in the journal Science Translational Medicine.
Ebola first appeared in 1976 and causes an especially frightening and deadly form of hemorrhagic fever. Patients die of shock but may bleed internally and externally. Depending on the strain, it kills between 25 and 90 percent of patients.
There is no existing treatment and no vaccine. "It is horrifying," says Gene Olinger of the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID), who worked on the study.
Various strains of the virus pop up unpredictably across Africa, perhaps as people venture into forests to hunt wild animals, especially monkeys and apes, known as bushmeat. The virus infects apes and monkeys and it infects people who are exposed to bodily fluids, such as blood.
Scientists are working on a variety of approaches to treat the virus and also to make a vaccine. This latest possible treatment comes from the vaccine work.
"We were developing a vaccine and the vaccine was tested in mice and the mice were used to make the monoclonal antibodies to understand how they protected from disease," Olinger said in a telephone interview.
Antibodies are immune system proteins that recognize and attack invaders such as bacteria and viruses. Monoclonal antibodies are engineered to recognize a specific pathogen – in this case, a strain of Ebola.
The team chose three of the antibodies and made them into a cocktail called MB-003. They’ve been testing it in monkeys, which can be infected with Ebola in much the same way as humans can.
In this latest test, 43 percent of the monkeys recovered and survived when treated as long as five days after they were infected, even after they started showing symptoms. "We were excited," says USAMRIID’s James Pettitt.
Usually once symptoms start, that means the virus is already overwhelming the body’s defenses.
Olinger thinks a higher dose of the antibodies might work even better. The antibodies must be given intravenously, but clinics being run by groups such as Doctors Without Borders have the facilities to offer the treatment, he says.
More testing is needed first, before trying it on people. A company in Canada is working on developing other antibodies that might improve the treatment. And this particular cocktail recognizes most, but not all, the known strains of Ebola.
Kentucky BioProcessing in Owensboro, Kentucky makes MB-003 using tobacco plants. The plants are genetically engineered to produce "humanized" versions of the antibodies. "It creates a green juice and we purify the antibody from it," Pettitt says. "It is a much cheaper and quicker way to produce the antibody."
"Our facility can produce these proteins in two weeks at a substantial reduction in cost to other production methods," says Barry Bratcher, the company’s chief operating officer. "This advanced method of manufacturing allows us to address needs quickly and inexpensively."
Africa is loaded with nasty viruses <http://www.nbcnews.com/health/new-virus-africa-looks-rabies-acts-ebola-1C6435402> . Lassa fever virus comes from a family known as arenaviruses and causes 500,000 cases of hemorrhagic fever a year. Crimean-Congo hemorrhagic fever and Rift Valley Fever viruses are in another family called bunyaviruses; Ebola and its cousin Marburg viruses are in a family called filoviruses.
The World Health Organization documents dozens of Ebola outbreaks <http://www.nbcnews.com/id/22028651/ns/health-infectious_diseases/t/new-deadly-strain-ebola-emerges/#.UhSy4JLvtPM> , including an outbreak of Ebola Zaire that killed 128 people out of 143 infected in Congo in 2003 – a 90 percent fatality rate – and a 2007 outbreak in the Democratic Republic of Congo that killed 187 out of 264 people infected for a 71 percent fatality rate.
I report this without knowing more; it’s certainly a surprise to me.
And here is the alternate view on reactionless drive:
The World Just Changed
Throughout the course of human affairs, there have been a few defining moments when Technology has changed History. Johannes Gutenberg did it when he invented the printing press. Alexander Graham Bell did it again, when he invented the telephone. Alexander Fleming brought us Penicillin, and Dr. Banting brought us insulin. And all of us have witnessed the birth of the computer, the Internet, and the Cellular telephone. All of these technological turning points have changed our lives; and every single one without exception owes its existence not only to brilliance, but to tenacity.
Why tenacity? Because true invention, by its very nature, challenges the accepted dogma of that which is known. In the grey and sober world of solemn science, true invention sometimes demands that new rules be written; and at other times, true invention requires that the entire rulebook be thrown out the window.
But throwing the entire rulebook out the window is the very definition of scientific heresy; and it is not well tolerated in the world of science. And those who attempt to do so, are even less well tolerated. They are shouted at jeered at, laughed at, and held in contempt. They are objects of ridicule and scorn; for science does not abandon its rulebook without a fight.
Now, let me introduce you to Roger Shawyer.
Shawyer’s a British Aerospace Engineer. He started off in the Industry working on such things as guided missiles, radar, and communication systems. He wound up at working at EADS Astrium (a European spacecraft and payload manufacturer) for 20 years. While there he occupied various positions, including Head of Department for payload equipment, as well as Project Manager for various different payload deployments. He was also responsible for the initial design of the Galileo navigation payload. Shawyer’s a heavyweight, and he knows what he’s doing.
But then, a terrible thing happened: he had an idea.
He envisioned a brand new approach to rocketry; an approach that would make use of the new discoveries being made in the confusing world of quantum theory. And his vision cost him both his job, and his credibility; because he envisioned a magical space drive that didn’t involve rockets, something less aligned with Physics and more aligned with Star Trek.
Perhaps a bit of clarification is in order.
Rockets work by throwing something out the back of the rocket. Imagine that you were standing on a skateboard, holding a baseball; and imagine that you took that baseball, and threw it as hard as you could. The skateboard you were standing on would move in the other direction, taking you (hopefully) with it; and that’s how a rocket works.
That big, bright exhaust plume coming out the back of the rocket? that’s highly energetic gas, being thrown out the back of the rocket at great speeds. It is the reason the rocket goes up, and is perhaps the best known example of Newton’s third law of motion: "For every action, there is an equal and opposite reaction."
Unfortunately, you have to take your fuel with you; and when you run out of fuel, that’s it. You coast. That’s just how rockets work. And that’s the only way they can ever work, and if you think differently, well, you can just take it up with Sir Isaac Newton, the Revered Father of Physics. Insert sarcastic chuckle here.
Unfortunately, Shawyer thought differently.
He believed that he’d found a way in which, by manipulating specific properties in the confusing and largely unexplored world of Quantum Physics, he could obtain thrust – a force pushing in a specified direction – WITHOUT having to throw something out the back. Which would be a clear violation of Newtons third law of motion.
In other words, blatant scientific heresy.
When he developed his mathematical model, he showed it to his employer; they showed no enthusiasm. When he pushed, their mathematicians gently reminded him of Newton’s Third Law, and suggested he read a book on the subject. When he requested funding, it was denied; and when he suggested building a working model, he was laughed at. Shawyers folly; might as well build a flying saucer. His career prospects did more than dim; they largely disappeared.
Undaunted, he started his own company called SPR (Satellite Propulsion Research). He refined his mathematics, defined the shapes, determined the energies required, and built a model.
And it worked.
He wrote a detailed scientific paper and sent it to every peer reviewed journal, only to have it rejected by every one. You see, Newton is right. Newton is always right. And because Newton is always right, you must be wrong. And since you must be wrong, you’re not worth our time.
That was the prevailing theme of the rejection letters. When there were rejection letters; many simply trashed his papers without bothering to comment.
He begged scientists to come and see his working model; they all refused. You see, Newton is always right. Since Newton is always right, you must be wrong. Your machine might move, but it’s not because you’ve made any great discovery; you’ve just got some subtle side effect happening here. Nothing important enough to warrant looking at.
Some scientists went further; he was accused of fraud.
He published a video of the machine in action on YouTube; it was ignored. (You can watch that video here: https://www.youtube.com/watch?v=57q3_aRiUXs )
Finally came a break. The popular British science magazine New Scientist became interested; and after investigating Shawyers story, they not only published his story, they put him on the cover. "The End of Wings and Wheels". Finally. A bit of traction.
The response was vitriolic. "gobsmacked by the level of scientific illiteracy." "meaningless double-talk". Influential science fiction writer Greg Egan even distributed a public letter stating that "a sensationalist bent and a lack of basic knowledge by its writers" was making the magazine’s coverage sufficiently unreliable "to constitute a real threat to the public understanding of science". Other influential scientists piled on as well; but New Scientist stood by their story.
They were the only ones that did, until 2009. Enter the Chinese, stage left.
China doesn’t have quite the same reverence for the western Gods of Science that Western Science does; but they do have great respect for, and great understanding of, both Mathematics and Physics. They examined Shawyers work in detail; and they felt that it could work. So, they built a model, and tested it.
And it worked.
And they reported it; and that’s when things hit the fan. For the Chinese report caught the attention of the very influential western trade journal Aviation Weekly, and they did a story on the research. And suddenly every aviation reporter on planet Earth was calling China. But all they were getting was the Chinese equivalent of "We’re sorry, but this number is no longer in service". The Chinese Government brought down the Iron Curtain, and if the research carried on, it did so out of view.
But people in the West were starting to sweat. What if Shawyer were right? What if… Dear God… what if Newton were Wrong!??!?
So, they turned it over to NASA. And they did so with a great sigh of relief; for it was felt that NASA would get to the bottom of things, demonstrate the error, prove Shawyer wrong, and restore Newton to the Throne.
Unfortunately, on July 30, 2014, NASA proved that it worked.
At this point, the entire scientific community is leaning against the wall, sweating profusely, and breathing very hard. Because this magical machine has been proven to work. Not just once, but three times; once by Shawyer, once by the Chinese Academy of Science, and once by NASA. The NASA approach was particularly rigorous in isolating the elements, and proving that the effect was not a spurious side effect of some other process. NASA meticulously ruled out every other possible reason; NASA proved that, beyond any reasonable doubt, the machine that Shawyer built, works. It’s not yet clear how or why it works – although Shawyer will patiently explain it to anyone who will listen – but it does work.
The implications of this discovery are immense.
For one, it gives us the Solar System; using a scaled up version of Shawyers drive, we can get to Mars in a few weeks, and to any point in the solar system in not much longer than that. Shawyers drive requires electricity, and for large amounts of thrust it requires a lot of electricity; but that’s all. No expendable fuel source is required. For Science Fiction fans, it provides the practical equivalent of the Impulse Power drive used in the science fiction series Star Trek.
Another likely application is in the use of aircraft and helicopters. Both achieve flight through interaction with the atmosphere; this limits aircraft to a practical limit of 35,000 feet. But Shawyers drive doesn’t require an atmosphere, and it doesn’t require jet fuel. Similarly, it provides propulsion through the water without propellers; and this ushers in a whole new world of super quiet and ultra fast submarines.
We haven’t yet reached the corners of our understanding as to how fundamentally this discovery will change our lives; but it will change our lives. And at some point, Roger Shawyer should be considered for the Nobel Prize. For, just like Gutenberg, Banting, Bell and all the other pioneers of Science, Shawyer is one more example of how a clarity of vision, coupled with an unyielding tenacity, can change the world.
And indeed, Tenacity and Vision are the only things that ever have.
I confess I wish it were all true. Alas, I think they have found flaws in their testing systems.
Your article on the Dean Drive brought back memories I haven’t thought about in 55 years. The Dean drive was all the rage in my high school Physics class (PSSC Physics) back in 1960. I remember seeing a demo on the Today Show and being very excited because it meant interplanetary space flight was possible. Dean claimed he had a patent which gave his claim even more importance. Somehow one of my classmates got ahold of the patent number and I sent for it. It was obvious from the beginning, even to a high school physics student,that the patent was a fraud as far as a reaction-less drive was concerned. It took me a little longer to figure out that the demo took advantage of the resonance frequency of the bathroom scale.
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