Domain: imgur.com
Stories and comments across the archive that link to imgur.com.
Stories · 71
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Police Capture Second Marathon Bombing Suspect in Watertown, Mass.
Police have captured believed Boston Marathon bomber Dzhokhar Tsarnaev, who was "pinned down" in a boat stored behind a house in Watertown, Massachusetts. You can listen to the live police feed here. -
One Boston Marathon Bomb Suspect Dead, Other At Large After Shootout With Police
theodp writes "During the night, The Tech broke news that gunshots were reported at MIT near 32 Vassar Street (the Ray and Maria Stata Center for Computer, Information, and Intelligence Sciences), and one officer was shot and taken to Mass General Hospital. MIT's Emergency Information page also reports that injuries have been reported. Sadly, CNN is now reporting that the university police officer has died. Look for updates on Twitter." The two suspects identified earlier as being behind the Boston Marathon bombings are believed to be responsible for this. They were found by police. One suspect, 26-year-old Tamerlan Tsarnaev, was killed in a shootout. The other suspect, 19-year-old Dzhokhar Tsarnaev, is still being pursued. The Associated Press reports that the two are believed to be from the Russian region near Chechnya. During the firefight, the suspects threw explosive devices at police. Public transit in Boston has been shut down, and hundreds of thousands of people have been asked to not leave their homes. Here are live feed for local TV news and emergency services audio. Police have been warned that the remaining suspect may have a suicide vest.
Reader Okian Warrior points out a related story worthy of notice: "The 4chan crowd, poring over images of the Boston marathon, identified two dark-skinned and bag-carrying suspects (among others). This was then picked up by The New York Post, who ran the image on Thursday's front page with the headline 'Feds seek these two pictured at Boston Marathon.' And now, a completely innocent teen now finds himself scared to leave his home." -
One Boston Marathon Bomb Suspect Dead, Other At Large After Shootout With Police
theodp writes "During the night, The Tech broke news that gunshots were reported at MIT near 32 Vassar Street (the Ray and Maria Stata Center for Computer, Information, and Intelligence Sciences), and one officer was shot and taken to Mass General Hospital. MIT's Emergency Information page also reports that injuries have been reported. Sadly, CNN is now reporting that the university police officer has died. Look for updates on Twitter." The two suspects identified earlier as being behind the Boston Marathon bombings are believed to be responsible for this. They were found by police. One suspect, 26-year-old Tamerlan Tsarnaev, was killed in a shootout. The other suspect, 19-year-old Dzhokhar Tsarnaev, is still being pursued. The Associated Press reports that the two are believed to be from the Russian region near Chechnya. During the firefight, the suspects threw explosive devices at police. Public transit in Boston has been shut down, and hundreds of thousands of people have been asked to not leave their homes. Here are live feed for local TV news and emergency services audio. Police have been warned that the remaining suspect may have a suicide vest.
Reader Okian Warrior points out a related story worthy of notice: "The 4chan crowd, poring over images of the Boston marathon, identified two dark-skinned and bag-carrying suspects (among others). This was then picked up by The New York Post, who ran the image on Thursday's front page with the headline 'Feds seek these two pictured at Boston Marathon.' And now, a completely innocent teen now finds himself scared to leave his home." -
LucasArts Employees Hold Wake & Eulogy; Vader Still Roams
Dawn Kawamoto writes "LucasArts employees held a wake Friday night, days after Darth Vader Disney slayed their studio. Taking the high road, two LucasArts employees put together a eulogy that offers a retrospective on the culture, memories and accomplishments of the team. Most of us who've witnessed a blood bath at the workplace aren't as charitable. Darth Vader Disney is expected to strike again in the next two weeks at its studio and consumer product divisions." -
Ask Slashdot: Building a Cheap Computing Cluster?
New submitter jackdotwa writes "Machines in our computer lab are periodically retired, and we have decided to recycle them and put them to work on combinatorial problems. I've spent some time trawling the web (this Beowulf cluster link proved very instructive) but have a few reservations regarding the basic design and air-flow. Our goal is to do this cheaply but also to do it in a space-conserving fashion. We have 14 E8000 Core2 Duo machines that we wish to remove from their cases and place side-by-side, along with their power supply units, on rackmount trays within a 42U (19", 1000mm deep) cabinet." Read on for more details on the project, including some helpful pictures and specific questions. jackdotwa continues: "Removing them means we can fit two machines into 4U (as opposed to 5U). The cabinet has extractor fans at the top and the PSUs and motherboard fans (which pull air off the CPU and remove it laterally — (see images) face in the same direction. Would it be best to orient the shelves (and thus the fans) in the same direction throughout the cabinet, or to alternate the fan orientations on a shelf-by-shelf basis? Would there be electrical interference with the motherboards and CPUs exposed in this manner? We have a 2 ton (24000 BTU) air-conditioner which will be able to maintain a cool room temperature (the lab is quite small), judging by the guide in the first link. However, I've been asked to place UPSs in the bottom of the cabinet (they will likely be non-rackmount UPSs as they are considerably cheaper). Would this be, in anyone's experience, a realistic request (I'm concerned about the additional heating in the cabinet itself)? The nodes in the cabinet will be diskless and connected via a rack-mountable gigabit ethernet switch to a master server. We are looking to purchase rack-mountable power distribution units to clean up the wiring a little. If anyone has any experience in this regard, suggestions would be most appreciated." -
Discovery Increases Odds of Life On Europa
tetrahedrassface writes "Observations of spectral emissions from the surface of Europa using state of the art ground based telescopes here on Earth have lent data that indicate the surface of the Jovian moon is linked with the vast ocean below. The observations carried out by Caltech's Mike Brown and JPL's Kevin Hand show that water is making it from the ocean below all the way up to the surface of the moon. In their study (PDF) they noticed a dip in the emission bands around lower latitudes of the moon, and quickly honed in on what they were seeing. The mineral of interest is epsomite, a magnesium sulfate compound that can only come from the ocean below. From the article: 'Magnesium should not be on the surface of Europa unless it's coming from the ocean,' Brown says. 'So that means ocean water gets onto the surface, and stuff on the surface presumably gets into the ocean water.' Not only does this mean the ocean and surface are dynamically interacting, but it also means that there may be more energy in the ocean than previously thought. Another finding is that the ocean below the icy surface of Europa is basically very similar to an ocean on Earth, giving the neglected and premier solar body for life past Earth another compelling reason for being explored." -
Feedback On Simcity Gets User Banned From EA Forums
An anonymous reader writes "EA's latest SimCity game requires users to log on online even for single player. After being unable to log on for three hours, one of its users chimed in with his very polite $0.02 opinion, only to get himself banned by EA admins. Another great victory for DRM." Update: 01/29 18:00 GMT by S : The player's ban has been lifted, and it seems to have happened for an unrelated issue anyway. -
Feedback On Simcity Gets User Banned From EA Forums
An anonymous reader writes "EA's latest SimCity game requires users to log on online even for single player. After being unable to log on for three hours, one of its users chimed in with his very polite $0.02 opinion, only to get himself banned by EA admins. Another great victory for DRM." Update: 01/29 18:00 GMT by S : The player's ban has been lifted, and it seems to have happened for an unrelated issue anyway. -
Feedback On Simcity Gets User Banned From EA Forums
An anonymous reader writes "EA's latest SimCity game requires users to log on online even for single player. After being unable to log on for three hours, one of its users chimed in with his very polite $0.02 opinion, only to get himself banned by EA admins. Another great victory for DRM." Update: 01/29 18:00 GMT by S : The player's ban has been lifted, and it seems to have happened for an unrelated issue anyway. -
Why "We The People" Should Use Random Sample Voting
Frequent contributor Bennett Haselton writes this week with his explanation of how an improved algorithm on the White House's petition-creation site could do away with Death Star petitions and even improve on the existing serious ones. Read on below for his modest proposal on that front.With a little boost from 4chan, a petition for the U.S. government to build a working Death Star has reached 30,000 signatures and counting, over on the White House's Department Of Let's See How Fast We Can Get 75,000 Signatures To Legalize Pot (or as it's officially known, "We The People"). This is the website where any of the member of the public can create a petition that other users can sign, and if the petition receives 25,000 signatures in 30 days, the White House will issue an official response. (Alan Boyle is taking suggestions on how the White House should respond to the Death Star request. How about: "4chan. You will never find a more wretched hive of scum and villainy.")
Cynics will say that the whole process was already a joke anyway. Even looking at the most popular non-Death-Star related petitions on We The People, most of them express standard left- or right-wing positions on hot-button topics in a manner that's extremely unlikely to convert anyone who doesn't already agree. Since everyone already knows that those some large segment of the population holds those positions, nobody would be surprised that any one of those petitions would be able to gather 25,000 signatures, and so there would be no pressure on the White House to change any of their official positions as a result.
On the other hand, I don't think this means that online petitioning can't work. Rather, I think a sligthly different algorithm could greatly improve the quality of the suggestions that get filtered to the top and trigger a response from the White House. At least one algorithm exists that (a) would prevent the system from being "gamed" by any large, organized group (whether 4chan or the NRA); and (b) would reward the petitions that were supported by the highest percentage of the general user population (or, if you prefer, the petitions that were supported by the highest percentage of credentialed experts in a given field).
The algorithm is the same one that I've advocated for preventing cheating on digg, or identifying the best "hidden gems" among newly released songs (and political arguments), or adjudicating Facebook abuse complaints -- have each petition voted on by a random subset of users registered on the We The People site. Based on this random sampling method, the petitions that have the highest percentage of "yes" votes, are assumed to be the ones with the broadest level of support among registered users, and the ones most deserving of a response from the White House.
Example: Suppose there are 250,000 registered users on the We The People site. A user creates a new petition, and somehow manages to pass some "threshold" that is implemented to screen out blatant time-wasters. (Perhaps you have to gain 100 signatures to pass the first threshold. I'd prefer it if you could clear the first hurdle just by paying $5 with a credit card, but this might anger purists who say that petitioning the government should always be free.) Your petition then gets emailed out to 100 randomly selected other users on the site, who vote to either Agree or Disagree. (In practice, in order to get 100 votes cast, you'd have to email more than 100 people, taking into account their response rate. So if only 50% of users respond to an email request for votes, email it to 200 randomly selected users to ensure you get about 100 votes cast.) Then petitions are sorted according to the percentage of users in their sample who voted to Agree. Petitions that got a high percentage of yes-votes, could be forwarded out to a wider audience (say, 1,000 users), to ensure that the initial high percentages of yes-votes wasn't just a fluke. Users in each random sample could also include comments about why they were voting a particular proposal up or down.
This sounds deceptively simple, but it makes it much harder for an organized online movement to hack the system. Say that 4chan manages to get 25,000 registered users in an attempt to push their favored petition to the top. This still means that, on average, their voters will comprise only about 10% of the randomly selected voters in any online poll - possibly enough to give an extra boost to a petition that already had broad support from regular users, but not enough to achieve a coup all by themselves.
Perhaps you'd object that even if such a system could not be manipulated by organized mobs, it would still leave the approval rating in the hands of non-expert ordinary citizens (even if citizens registered on We The People are slightly more informed than average). Whether you think this is a good thing, depends on whether you think the purpose of the site is to reflect the will of the people, or to provide informed advice to the President.
But if you want to get a random sampling of expert opinions, that's pretty easy as well. For petitions on, say, economic matters, just have a subset of users consisting of economics professors from accredited universities across the country. (These credentials would have to be confirmed manually by White House staff, but it's not that hard to verify that someone owns an .edu address and that their university webpage identifies them as an econ professor.) Then any petition on an economic matter could be submitted to a random sample of economics professors to be rated by them. If a petition gets a rating from economics experts that is wildly different from the rating it gets from the general user population, that suggests something interesting is going on (either econ professors are out of touch, or the general public is misinformed). But if a petition gets high levels of support from the public and the relevant expert group, that would seem to justify a response from the White House, much more so than some of the idiotic petitions currently pulling 65,000+ votes on We The People.
Something almost like this has actually been done by the IGM Economic Experts Panel in Chicago, which surveyed a group of 41 economists that the IGM believed to be among the best in the world, representative of the political left, right, and center. The survey found a high degree of consensus on questions that the general public is divided on, such as the fact that 40 out of 41 experts agreed with the statement:
All else equal, permanently raising the federal marginal tax rate on ordinary income by 1 percentage point for those in the top (i.e., currently 35%) tax bracket would increase federal tax revenue over the next 10 years.
To people who have heard celebrity conservative economists claiming that raising marginal tax rates lowers tax revenue, it might come as a surprise that virtually all expert economists in the IGM's sample, including a representative number of self-described conservatives, agreed that it does not. But don't just soak the rich and call it a day; most economists in the IGM's sample also disagreed that:
The cumulative budget shortfalls in the US over the next 10 years can be reduced by half (or more) purely by increasing the federal marginal tax rate on ordinary income for those in the top tax bracket.
Of course those were questions of fact (what economists call positive economics), while petitions address questions of what should be done (what economists call normative economics, and which varies according to your values and goals). But even economists with diverse political leanings often advocate similar policies; NPR interviewed 5 economists spanning the spectrum from left to right, and found across-the-board consensus in favor of 6 proposals, which you can read here. And hey, one of them is legalizing pot!
If We The People implements a system for polling a random sample of economics experts, I think their first order of business should be to have them rate the ideas in that 6-point platform. The five-person panel claimed that all of these ideas have broad support from economists across the political spectrum, but it would be good to know for sure. And for any of those six points that has broad consensus support from experts, it should be incumbent on the White House to declare whether they agree, and if not, why not.
More generally, random-sample voting will always reveal more useful information -- whether about the opinion of the public, or about the opinions of experts -- than a petition site that lets passionate users self-organize into signature mobs. As I've been saying ever since my first story advocating this algorithm, the only site I'm aware of that currently implements random-sample voting correctly, is HotOrNot, which shows users a random series of pictures and lets users rate the picture's hotness on a scale of 1 to 10. Can we not make at least that much effort to design a working system, when it comes to deciding which petitions get a response from the White House?
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Is Our Infrastructure Ready For Rising Temperatures?
Hugh Pickens writes "Megan Garber writes that last weekend, a US Airways flight taxiing for takeoff from Washington's Reagan National Airport got stuck on the tarmac for three hours because the tarmac had softened from the heat, and the plane had created — and then sunk into — a groove from which it couldn't, at first, be removed. So what makes an asphalt tarmac, the foundation of our mighty air network, turn to sponge? The answer is that our most common airport surface might not be fully suited to its new, excessively heated environment. One of asphalt's main selling points is precisely the fact that, because of its pitchy components, it's not quite solid: It's 'viscoelastic,' which makes it an ideal surface for the airport environment. As a solid, asphalt is sturdy; as a substance that can be made from — and transitioned back to — liquid, it's relatively easy to work with. And, crucially, it makes for runway repair work that is relatively efficient. But those selling points can also be asphalt's Achilles heel. Viscoelasticity means that the asphalt is always capable of liquefying. The problem, for National Airport's tarmac and the passengers who were stuck on it, was that this weekend's 100+-degree temperatures were a little less room temperature-like than they'd normally be, making the asphalt a little less solid that it would normally be. 'As ironic and as funny as the imgur seen round the world is, it may also be a hint at what's in store for us in a future of weirding weather. An aircraft sinking augurs the new challenges we'll face as temperatures keep rising.'" -
Minecraft Map of Northwestern Campus Printed In 3D
erich666 writes "Ben Rothman has created a five-foot-wide scale model of most of Northwestern University, where he was a sophomore this past year. This campus model is unique: it is the first modeled in Minecraft and then printed on a 3D printer. It is also the largest Minecraft 3D print to date, and will be on display in the main lobby of the largest building on campus in a few weeks. Ben began in November and spent about 600 hours recreating the campus. He notes that "this felt like playing a game more than a modeling task." The cost of the print material was about $2000 to $2500, well less than the cost of the display case being built for it (admittedly, labor costs are included for the case). The free Mineways program was used for export. It can help upload an exported Minecraft model to Shapeways, i.materialise, or other 3D print service. Models cost as little as $5." -
MIT Fusion Researchers Answer Your Questions
You recently got the chance to ask a group of MIT researchers questions about fusion power, and they've now finished writing some incredibly detailed answers. They discuss the things we've learned about fusion in the past decade, how long it's likely to take for fusion to power your home, the biggest problems fusion researchers are working to solve, and why it's important to continue funding fusion projects. They also delve into the specifics of tokamak operation, like dealing with disruption events and the limitations on reactor size, and provide some insight into fusion as a career. Hit the link below for a wealth of information about fusion. 1. What have we learned?
by jank1887
Fusion is one of those technologies that is always '50 years away,’ even 50 years ago, maybe even 50 years from now. So, looking at what's actually happened recently: What do we actually know now that we didn't know 10-15 years ago that gives support to the notion that we're making progress? Or, what are the 'big' things we know now? Similarly, what are the things we still don't know that we could reasonably expect to find answers for in the next 10-15 years?
MIT Researchers: As researchers in this field, we have heard the expression "Fusion is 50 years away and always will be" more times than we would like to admit. The implication of this statement is that no real progress has been made in the field, which is simply not true! We have made a great deal of progress, even in the last 10–15 years (which have been very lean times for funding). We’ll try to summarize some of the new findings, in no particular order:
1) Internal Transport Barriers/Reversed Shear operation –
We have actually discovered a way to improve upon the performance that we get in H- mode plasmas. These improvements come in the form for so called internal transport barriers. In the past 10–15 years we have begun to understand how to modify the current flowing in tokamak plasmas so that we create effectively what is a barrier in the middle of the plasma. Like the edge barrier in H-mode plasmas, this barrier restricts particles and energy from escaping the plasma and enhancing the overall performance. 2) I-mode –
In just the last 5 years, a new operational regime has been discovered on the Alcator C-Mod tokamak at MIT. This is termed the I-mode, or “Improved L-mode” regime. When the tokamak is operated in this manner it exhibits excellent energy confinement properties, keeping the plasma hot. At the same time the plasma does an excellent job of expelling impurities which dilute the fusion fuel and reduce the number of fusion reactions which can occur. It is particularly important to us as it was first observed on Alcator C-Mod, and is now under active development at many other tokamaks around the world.
3) Development of Predictive Models –
Great advances have been made in the development of predictive computer models, such as gyrokinetic and magnetohydrodynamic (MHD) formulations. Years of experiments have revealed that plasma turbulence is often primarily responsible for the loss of particles and energy from fusion reactors. In the past 10–15 years we have developed advanced models which are thought to contain sufficient physics to simulate plasma turbulence and predict the performance of future fusion devices. At this time we are in the process of validating these models, i.e. comparing them directly with experiment to ensure they are correct, but we are approaching the ability to reliably predict the performance of fusion plasmas without the need for a fusion reactor. This can motivate engineering design and operational choices for future fusion devices.
4) Self-acceleration of the plasma (intrinsic rotation) –
Over the past decade, it has been discovered (on Alcator C-Mod and elsewhere) that plasmas can spontaneously rotate, at speeds of tens of kilometers per second. (Imagine the donut-shaped plasma spinning on its axis.) This turns out to have beneficial effects for stabilizing turbulence at the edge, as the spinning plasma causes the turbulent eddies to break up before they can carry hot plasma out of the core. This is an exciting area of research that could have big implications for the performance of a tokamak reactor.
5) Disruption mitigation –
One of the main problems with a tokamak is the ‘disruption’, when the plasma energy is suddenly lost, stopping any fusion that is occurring and requiring a restart of the reactor. (See the question below for a lot of detail about this!) In extreme cases, these disruptions can cause damage to the wall of the tokamak – which would require repairs before the machine can be restarted. Over the past decade, we have developed techniques to mitigate these disruptions, causing the plasma to come to a rapid shutdown that does not negatively affect the wall condition. Work is underway to scale these techniques up to a reactor-size device (ITER).
6) ELM control/avoidance –
Another longstanding problem with tokamaks is periodic ‘bursts’ of energy from the edge called Edge-Localized Modes (ELMs). In today’s devices, ELMs are not a problem, but in ITER and future reactors, they could carry enough energy to damage the wall in the divertor region (where most of the energy comes out). There has been rapid progress lately (past 15 years) in ways to control these ELMs by making them more rapid and smaller, such as using resonant magnetic perturbation (RMP) coils to distort the shape of the confining magnetic field, or ‘pellet pacing’ (firing small pellets of deuterium fuel into the machine 50–60 times per second, which triggers an ELM), or vertical ‘kicks’ in which the control system suddenly jogs the plasma position a few centimeters vertically, also triggering an ELM. Between these techniques and the recently discovered I-mode (which doesn’t have ELMs), this is a problem that is well on the way to being solved.
7) High-Z walls –
This is a particular point of pride for Alcator C-Mod. Running a tokamak with walls made of refractory metals has many advantages because of the extreme capacity of these materials to absorb heat loads, but there are disadvantages as well, such as how radiative these high atomic number elements are if they get into the plasma as impurities, or how metallic materials distort when they melt, rather than ablating like carbon-fiber composites. Alcator C-Mod (which has a molybdenum wall) and other tokamaks have recently shown that it is possible to reliably run a tokamak with high-Z refractory metal walls, which will almost certainly be a feature of future reactors.
2. Power Loss Scenario in Alcator C-Mod?
by eldavojohn
Not to raise any fears -- rather out of genuine curiosity -- what happens when the magnetic fields that hold the 90,000,000 degrees Celsius plasma in place fail or loser power on the Alcator C-Mod? I understand it's probably in prototype mode, but what sort of safety advantages or disadvantages do Alcator C-Mod designs offer over conventional, large-scale designs? Does the plasma come into contact with the toroidal superconducting coil? Then what?
Geoff Olynyk answers: Actually, that’s exactly what my research is on! The event you describe is called a "disruption." Holding a hot plasma stationary using magnetic fields without it ever touching material surfaces is very difficult – Richard Feynman once compared it to trying to "hold Jello with rubber bands." For any number of reasons, like a magnetic coil losing power, the control system not being able to juggle the plasma position quickly enough, or the plasma hitting a stability limit (pressure or density goes too high), it’s possible for the plasma to hit the wall. The most important thing to know, though, is that when this occurs (and it does, frequently, in today’s experiments – although it’ll have to be a very rare occurrence in a real power reactor so it produces uninterrupted electricity), it is no risk to the environment or to safety.
To understand what happens, you have to realize that the plasma is very, very light. In the Alcator C-Mod tokamak, it has a mass of only about 0.001 grams – about one- fiftieth as much as the smallest drop of water you can get from an eyedropper. (This is with a plasma volume of about a cubic meter – a fusion plasma is actually a pretty good vacuum!) So even though it’s very hot, it doesn’t actually have a lot of thermal stored energy to flow into the wall if confinement is suddenly lost. There is actually more energy stored in the current flowing in the plasma (in C-Mod, about a million amperes), which also gets deposited on the wall. In C-Mod, thermal stored energy is about 50– 150 kJ and magnetic stored energy is almost 1000 kJ. The problem is that as we go to larger machines (like ITER, or a reactor), the amount of stored energy in the plasma scales like the cube of the size, and the wall area only scales like the square of the size. So the energy deposited per square meter of wall area gets worse (larger) as we go up in machine size.
The plasma doesn’t hit the superconducting coils - it hits (really, deposits its energy on) the “first wall” of the chamber closest to the plasma. So, we do two things to make sure that the walls can survive these disruption events. The first is making them out of materials that can take a blast of heat, like tungsten, or else materials that ablate away rather than melting, like carbon fiber composites. The second is to develop “disruption mitigation” systems which can cause the plasma to radiate all its energy evenly over the entire wall surface, spreading the heat out and lessening the chance of causing localized melting. But I want to stress again - disruptions are an operational problem, meaning they might cause a power plant to be offline for a while, but they’re not a safety problem. There is no chance of a runaway reaction or meltdown in a fusion reactor.
3. Ubiquitous Fusion Power
by monsted
When will fusion power my house (or vehicle)?
MIT Researchers: This is obviously an impossible question to answer, but we can give some thoughts about when it might happen, and why. First, the current official plan is that ITER will demonstrate net fusion gain (Q = 10, that is, ten times more fusion power out than heating power put in) in about 2028 or 2029. (Construction will be done by about 2022 but there’s a six-year shakedown process of steadily increasing the power and learning how to run the machine before the full-power fusion shots.) At that point, designs can begin for a “DEMO”, which is the fusion community’s term for a demonstration power plant. That would come online around 2040 (and would putt watts on the grid, although probably at an economic loss at first), and would be followed by (profitable, economic) commercial plants around 2050.
This seems like a long time, and it is, but it’s important to understand that this is not the only possible path. You might say that we’re not a certain number of years away from a working fusion power plant, but rather about $80-billion away (in worldwide funding). We’ll get into this more in response to one of the other questions, but there are other experiments that could be done in parallel with ITER that would certainly speed up the goal of a demonstration power plant, if there were the money for it. Here is a graph based on a 1976 ERDA (predecessor to today’s DOE) fusion development plan, showing their four paths to a reactor, as well as a business-as-usual funding case that would never lead to a reactor, and in black is the actual funding amounts. (All values are adjusted to 2012 dollars.)In the U.S. at least, fusion funding hasn’t been anywhere close to what would be required for a “crash program” to get to a reactor. If it were, it would probably be possible to have a demonstration reactor in about twenty years. (This is not actually that long - given that it takes almost a decade to build a large fission reactor or hydroelectric dam!)
Fusion has a reputation of “always being thirty years away” (or fifty, or twenty). We want to address that head-on here: aside from a few over-optimistic predictions made in the very early days of magnetic fusion research (the 1950s), this reputation is undeserved. The reason it has taken so long to get to breakeven (ITER) is because since the end of the 1970s, funding for fusion research has been continually slashed, up to today, when the U.S. is proposing shuttering one of three remaining tokamak experiments, the Alcator C-Mod device at MIT that we all work on. Despite this, progress has been continuous. But if we had the money, we would be getting there quicker.
4. What are the economic numbers for a successful, commercial reactor?
by kestasjk
I know that the economics of larger reactor = more economical are well known with tokamaks. Does this mean you have a good idea of the minimum cost / generating capacity of the first commercial reactors? If so, what do those numbers look like?
7. Lower Limit on Tokamak Design
by gyepi
Are there any good guesstimates on how small a tokamak-based fusion reactor (which produces more energy than it consumes) can become? Theoretical limitations on the size of the reactor would have obvious implications for pragmatic issues.
MIT Researchers: Questions 4 and 7 are similar and we answer them together here.
The current thinking is that a tokamak fusion reactor will be about 1 gigawatt electrical, and about 2–3.5 gigawatts thermal (depending on how high-temperature the blanket is and thus how thermally efficient it can be). This is about the size of a current fission reactor or large coal-fired power plant.
Fusion researchers are working on smaller designs, though! At MIT, some students are working on a concept for a 350–500 MW (thermal) class fusion reactor, which would be cheaper to field and thus more likely to be built by private industry with limited access to capital. This is still early work, though, and the economic analysis is not done yet.
Cost estimates for a new technology like fusion cannot be terribly reliable, but several studies suggest that, with suitable developments in science and technology, the costs could be competitive with other methods of electricity generation. We recommend you read the ARIES-AT study (google it), which goes through all the factors that go into the cost of electricity (COE) for a fusion reactor, and compares their concept to other electricity generation options (fission, fossil fuels, etc.) A key advantage of fusion is in what economists call "external costs." These are costs borne by society as a whole and not by the generating industry. Environmental pollution, nuclear proliferation, and military operations to protect oil supplies are all examples of external costs for energy.
5. What Problems are Holding Back Successful Reactions?
by Bucc5062
Can you explain to a non-scientist what the biggest stumbling blocks are for an effective fusion reaction? Is it truly a matter of throwing money down an energy hole, or are there verifiable, measurable benchmarks that lead us from one step to the next? I.e. we’ve achieved X, now we need Y; when we get Y, we get Z and then achieve fusion. Is it the technology holding us back, the politics, or the science?
MIT Researchers: We know exactly what we need to do. Not everything has a solution yet – that’s why it’s still a research project! – but we generally know what the big challenges are to get to a working magnetic fusion reactor. Here is a non-exhaustive list:- 1 – Non-inductive current drive. We can’t rely on inductors to drive the plasma current since they are inherently pulsed (not steady-state). We think that lower hybrid current drive might be the solution, and are actively researching this on Alcator C-Mod.
- 2 – Confining a 'burning plasma.' This is the big question that ITER will resolve – can we really confine a plasma that is dominantly self-heated – that is, most of its energy comes from fusion reactions rather than external heating. Will new instabilities appear? Or can we confine the plasma as we expect we can.
- 3 – Confining a steady-state burning plasma while avoiding off-normal events. We have to do both of the previous points at the same time! And we can’t have disruptions too often or else the power plant won’t have a high enough duty factor. The goal is to have disruptions (which require a shutdown) occur less than once per year.
- 4 – Validated predictive capability for fusion-grade plasmas. We have made great progress in this field already (see our answer to an earlier question), but it’s not at the point yet that, say, fluid mechanics codes are, where Boeing can design an entire plane in the computer before ever building a scale model. We need our models of fusion plasma behavior to be accurate and reliable enough to design first-of-a-kind machines that we are 100% sure will work the way we think they will.
- 5 – Diagnosing a burning plasma. It’s really hard to tell any of the properties of the plasma even today, when we use pure deuterium fuel (instead of ‘live’ deuterium–tritium fuel), and our plasmas are colder than they would be in a reactor! You can’t, for example, stick a thermometer in to tell the temperature! We have to use subtle effects like bouncing a laser beam off the electrons and telling the temperature from the Doppler shift of the laser from the moving electrons (a technique known as Thomson scattering). Making these diagnostics work in the reactor environment, with higher plasma temperatures and a ferocious flux of neutrons coming out, is a great challenge.
- 6 – Better understanding of plasma–wall interactions. The plasma is confined by magnetic fields, and ideally doesn’t touch the wall at all, except in a very small area called the divertor. This means that the material challenges in the divertor are severe – we have to figure out a way to operate the plasma so that it’s hot in the center, but cold near the divertor, so that it doesn’t erode the wall too fast. This will be a limiting factor on how long you can run a fusion power plant for before you have to shut it down in order to do maintenance. Ideally, we’d want this to be every 2 years or so, like fission power plants today.
- 7 – Materials for plasma-facing components. We need to develop new materials that can withstand the high temperatures of the wall of a fusion reactor while resisting neutron damage and not becoming too activated by the neutrons that will pass through them. (There is some progress on this front with ferritic steels and silicon carbide.)
- 8 – Magnets that meet the plasma physics requirements and allow reactor maintainability at reasonable costs. (Some of us are working on demountable superconducting coil concepts that may eventually be the solution to this!)
- 9 – Design and materials for tritium fuel cycle and power extraction. Fusion reactors will breed their own tritium fuel from deuterium – this process has to be experimentally tested on a large scale (which will obviously require a burning plasma tokamak).
- 10 – Reliability, availability, maintainability, and inspectability (RAMI) of the reactor designs. We have to show that our concepts for reactors really are as good as we think they can be.
The point is that it’s not a money pit. There are unsolved challenges, but we know what they are, and with adequate support, these challenges will be overcome. This is why we are urging everyone to go to fusionfuture.org and write Congress asking them to keep supporting U.S. fusion research! (It’s very easy – there’s a link at the right on the website.)
6. NIMBY
by GeneralTurgidson
How do you explain the safety/benefits of fusion to a generation of people terrified of nuclear anything?
MIT Researchers:This is where fusion really shines. The two big problems (at least, perceived problems) of fission reactors are the risk of a meltdown, and what you do with the high-level radioactive waste. Fusion has neither of these issues!
Regarding the first, the reason why a worst-case accident in a fission reactor can be so devastating is because there is a lot of fuel in the reactor at any one time. There are well known accidents at Chernobyl (where the reaction ‘ran away’, making more power than the reactor was designed to handle) and Fukushima, where the fission chain reaction was safely shut down, but the cores melted down when the tsunami knocked out the cooling systems, due to ‘decay heat’ which is produced by the used fuel even after shutdown.
In a fusion reactor, it’s a completely different story. There will be less than a gram of fuel in a reactor at any one time—fresh deuterium–tritium fuel is continually added as it is burned—and so a runaway reaction is simply not possible. Decay heat isn’t a problem in a pure fusion system, again because there just isn’t any fuel sitting there undergoing nuclear reactions once the reactor is shut down. In general, this is one area where it’s a benefit that a fusion reaction is so hard to sustain! We have to try really hard to keep the plasma hot enough to undergo fusion in the first place, so if we just turn off the heating and fuelling systems, the fusion reaction will shut down very quickly.
As for the second benefit of fusion (waste), the reaction is completely different from that in a fission reactor. In fission, uranium (or other heavy elements like plutonium) split into pieces, producing hundreds of different isotopes, some of which are radioactive, with half-lives ranging from fractions of a second to millions of years. In fusion, the reaction is simple, deuterium + tritium helium + neutron. So there is no “waste” from the unburned fuel – any tritium that isn’t burned gets pumped out of the chamber and recirculated back in.
This is not to say that there will be no radioactive waste from a fusion plant. The reactor vessel itself will become activated because of the flux of neutrons passing through it, and will have to be treated accordingly when the plant is decommissioned (after, say, a 50-year operational period). But it’s important to note that this kind of radioactive waste is of a much lower level – it won’t have to be stored for very long before it will be “cool” enough to simply bury in the ground safely. And there is active research going on into new materials for fusion reactors that are more resistant to activation by neutrons, such as ferritic steel and silicon carbide.
Finally, fusion has great advantages for nuclear non-proliferation. Creating enough fission power plants to avoid climate change would mean that the plutonium moving around the world would be enough to create about 100,000 nuclear weapons. For fusion, it is much more difficult to use a reactor to make fuel for weapons. This is also something that we think a nuclear-skeptical public will appreciate about fusion power.
All of us are strong supporters of fission power, and we agree that at times, the nuclear power industry has not received a fair shake when compared to other sources of energy. But we think that the advantages of fusion power speak for themselves, and the public will be able to understand the risks and will support the construction of these plants. Obviously, having media that are able to explain things clearly and fairly are a necessity.
8. What do the numbers really look like?
by Erich
ITER is a hugely expensive project, and won't produce a commercially viable power generation system. In a lot of areas where research is done on things which don't work yet -- rockets, bridges, transmission systems, etc -- there's a general idea of how things might be able to "scale up" to meet the goals. Is tokamak fusion really in sight of being a commercially viable source of energy? If we need unobtanium to make a commercially viable reactor, wouldn't it make sense to wait until the materials are viable before making even larger tokamaks? Or is it still worth learning from these new, bigger, more expensive reactors?
MIT Researchers: You are exactly correct in your statement; ITER is an expensive project which will not produce electricity upon completion. However, ITER’s main purpose is not to put watts on the grid, but to demonstrate the scientific feasibility of fusion by creating a Q=10 plasma (10 times as much energy out as we put in). We do have a good idea of how to proceed with devices following ITER, namely DEMO, a full demonstration fusion power plant which will use the steam cycle to generate electricity from the fusion reactor. The basic layout of a reactor can be found here: http://www.fusionfuture.org/what-is-alcator- c-mod/c-mod-for-energy/
Although there is still plenty of research which remains, fusion is in sight of being a commercially viable energy source. We believe that we now understand the physics well enough to create the appropriate plasma conditions (this will be demonstrated on ITER) and we are working on the engineering challenges that lay between us and a commercial fusion reactor.
It is obviously impossible to predict when fusion will put power on the grid since the estimate can change drastically based on demand and overall funding levels. You are however, correct in noting that some of the biggest challenges involve the discovery/ development of materials which can resist the unique and harsh conditions associated with fusion reactors, namely, high heat and neutron fluxes. Due to its importance to the success of future devices, this is a very active and important area of research.
The international fusion community is attempting to address these issues in the following manner: Given the scope of the ITER project and the time required to build and test it, we are planning on constructing a materials testing facility named, IFMIF which stands for International Fusion Materials Irradiation Facility. This facility should be operated at the same time as ITER and will be addressing the materials issues associated with an eventual fusion power plant while ITER is demonstrated the scientific feasibility of a fusion reactor.
Given the time-scales for reactor construction, we think it would be unwise to wait for this materials testing to be complete before starting new machine construction. Addressing the remaining problems in parallel will most likely result in the quickest path to fusion energy.
9. Careers in Fusion?
by benjfowler
As practicing researchers, can you tell us about the health of the pipeline of young researchers coming into the field? Is there a glut of trained physicists at this stage, or is there still a need for trained specialists to enter the field, especially with ITER and follow-on machines coming online in the next couple of decades?
Nathan Howard answers: At this point in time fusion is actually a pretty healthy field in terms of young researchers and with emergence of the next generation devices such as ITER, there should be an influx of researchers stepping up to meet the need for trained specialists on these next gen devices. Currently in Europe and Asia, emphasis on fusion research is ramping up to support the research needs. These newly trained researchers are going to be the scientists working on ITER in 10-15 years.
Unfortunately, the US fusion program is in danger of going the opposite direction of the Asian and European programs. The current proposals made by the US are threatening the health of fusion in the US. The President’s 2013 budget proposal calls for drastic cuts to the domestic fusion budget to pay for increased funding for the ITER budget. However, if these cuts continue, there will not be a field for the young researchers to enter and the US fusion program is in danger of dissolving before ITER comes online.
This does not mean that a need for trained specialist will not remain, it just means that the young researchers in Europe and Asia will be filling these positions. Dr. Stewart Prager, the head of Princeton Plasma Physics Lab said it best, “We have a clear choice before us: The United States can either design and build fusion energy plants or we can buy them from Asia or Europe.”
As a young researcher myself, I am particularly affected by the choices that the US is currently making. Myself and other graduate students have been urging others who support fusion research to contact congress and tell them to continue to fund domestic fusion research. We put together a website, www.fusionfuture.org, which provides more information and people the ability to quickly and easily contact their congressmen to tell them to support research. Please support US fusion research and check out the site.
12. Patents?
by Anonymous Coward
Will patents get in the way of your research?
MIT Researchers: In general, we find that the tokamak labs of the world are extremely cooperative; patents have never been a problem. It does seem likely that the technologies supporting power plants will be highly patentable, but the sort of scientific knowledge we’re accumulating at present really isn’t. At some point, we expect to move from a collaborative to a competitive phase – but we’re not there yet.
11. What level of investment would get fusion going?
by Tragek
Do you think a program the size of the Apollo program could kickstart fusion to general availability? Or would a smaller program suffice?
14. What could you do with unlimited resources?
by petes_PoV
Given $1 trillion, the pick of the best brains in the world to work willingly on the project, a large enough location away from any and all governmental regulation and every facility you could ever need - when would fusion be commercially viable?
MIT Researchers: Questions 11 and 14 are similar and we have answered them together.
Any kind of question asking about a hypothetical massive increase in funding is tricky to answer. We probably couldn’t even spend a trillion dollars if we wanted to – just because it would take a long time to get enough people trained in plasma physics and fusion energy.
We can say this: an increase in funding would allow for different paths to be tried in parallel, like stellarators, tokamaks (ITER), spherical tokamaks, etc. Plus, we could build a facility in the United States to study the problem of plasma–wall interactions, which is a very important topic that has not been adequately studied up to this point (see our answer above about what steps are needed to get to a reactor).
We think that we’re roughly $80-billion away from a reactor. At current levels of funding (worldwide), that’s about 40 years. Even given access to huge amounts of money, it’s unlikely that a working reactor could be built in less than a decade – there are just too many facilities to build between current devices and a full-scale reactor in order to ensure success. But we could certainly do it faster than 40 years!
We want to note that “crash” programs like Apollo or the Manhattan Project succeeded because they took risks – they started work on building their systems before they had done all the homework. That is inherently risky, but these risks are mitigated by pursuing alternatives in parallel. Something similar could be done in fusion, given the money.
15. Your favorite books?
by eldavojohn
I'm not a physicist (software guy), but I've taken a few physics classes. At an early age I found a tattered copy of George Gamow's One Two Three . . . Infinity, which, although incorrect in some parts (I guess that's why they revised it and that's why 'speculations' was in the title), was perfectly written for my then-fifth-grade mind. It set me on a path toward science, and a few weeks ago I saw the same 1960s Viking Press edition and flipped through it, noticing what was slightly off and remembering it. I've since grown to love other obvious books by authors like Hawking, Penrose, Hofstadter, etc. So, quite simply, what are your favorite books for all minds, young and old? Also, can you annotate which are written for the layman's entry into the given field and which are written to encompass the field for the researcher? I find that some books start off with the jargon so strong and the references and footnotes so thick that you start to have to re-read every paragraph, as they're clearly condensing entire historic papers into lengthy sentences. Any fiction books worthy of influencing your work and desires?
Ian Hutchinson: My all time favorite novel is Godric by Fredrick Buechner. It's a wonderful first-person portrait of the prior life of a medieval hermit. My favorite physics teaching text is the Feynman Lectures on Physics, which comes from a remarkable effort by the most widely acclaimed american physicist of the 20th century to explain really advanced physics to undergraduates.
I really don't enjoy the genre of books that combine science popularization with metaphysical speculation. They are of course quite popular, but most are philosophically naive in a way that I find annoying.
Anne White: I like detective/adventure stories. I also enjoy reading plays, poetry and short stories – some authors I read over and over are Wolfgang Borchert, Julio Cortazar, Ray Bradbury and Samuel Beckett.
Recently, I've enjoyed reading The End of the Affair by Graham Greene, People of the Book by Geraldine Brooks, Jane Eyre by Charlotte Bronte and Her Fearful Symmetry by Audrey Niffenegger.
Influential books/stories that I remember reading when I was young : The Pearl (John Steinbeck), Catch-22 (Joseph Heller), Flatland, and Ender's Game.
Dennis Whyte:- For science non-fiction books, it’s a tie: The Selfish Gene by Richard Dawkins, and Wonderful Life by Stephen Jay Gould.
- Novel (in general subject area of science): The Baroque Cycle by Neal Stephenson
- Speculative fiction: Starship Troopers by Robert Heinlein
Geoff Olynyk: The Making of the Atomic Bomb by Richard Rhodes is the best non-fiction book I’ve ever read. It’s a bit long, but is a fascinating, well-written exploration of the project to develop the atom bomb (both in the U.S. and elsewhere).
This is not a science book, but The Rebel Sell by Joseph Heath and Andrew Potter (sold in the United States as Nation of Rebels) changed my life. I was into counterculture, "culture jamming," anti-advertising, that kind of stuff, and this book made me seriously reconsider all of it. I now understand that trying to be unique is futile in a world of seven billion, and I should just try to be a good person and do good for the world (hence working on fusion!) Potter’s follow-up The Authenticity Hoax, explores the search for authenticity in more detail, but it’s not nearly as good of a book as Rebel Sell.
Nathan Howard: I first became interested in physics by reading about astrophysics. I was specifically interested in black holes and so one of the first books I read (after some of the popular books by Hawking which are written for general audiences, e.g. A Brief History of Time) was a book by Kip S. Thorne called Black Holes and Time Warps. I really enjoyed this book. It did not require much technical background, just some basic mathematics, and it gave good explanations of black holes, relativity, and gravitational waves.
16. Why is fusion more useful than exploiting thorium?
by gestalt_n_pepper
I understand that in the long term, we would want fusion. But we face increasing energy problems over the next 50 years and severe energy problems before 2100. Wouldn't it make sense to allocate research and development resources to something that we know works?
MIT Researchers: First of all, fusion will be putting watts on the grid before 2100. It’s not going to be tomorrow, but it’s not going to be a hundred years, either.
We know how to build thorium fission reactors. It's been done. They have none of the major attractions of a fusion reactor in terms of safety, fuel resources, reduced waste, or non-proliferation. Worldwide thorium fuel resources are about the same as those of uranium. Thorium reactors might become part of the commercial fission reactor mix in the future, but they don't offer transformative possibilities for nuclear power the way fusion does.
That said, we think that the that the scale of the energy/climate problem demands that we (meaning: government and private industry where appropriate) pursue multiple lines of development into new energy sources. Obviously nobody wants to waste taxpayer money, so all proposals have to be evaluated for chance of success – but today, it’s limited by funding more than by a lack of good ideas. This shouldn’t be the case.
The key thing we want to get across is that it shouldn’t be a contest between “fund fusion” or “fund thorium research”. Fusion is extremely important for humankind and should be funded – if thorium fission also has promise, it should be funded too.
17. How is fusion power harnessed?
by circletimessquare
The talk is always about reaching break-even with fusion. What about capturing the power? Are we generating heat that will drive steam turbines? What schemes exist for capture and harnessing the power generated by fusion?
MIT Researchers: In a magnetic fusion reactor, each deuterium-tritium fusion produces a 3.5 MeV (mega- electronvolt) alpha particle (helium nucleus) which deposits its energy in the plasma (this self-heating is how you can have an ‘ignited’ plasma which doesn’t require much or any external heating), and a 14.1 MeV neutron, which deposits its energy in a thick lithium blanket surrounding the toroidal reaction chamber. But in the end, all of it comes out as heat!
For a conservative fusion reactor design, this heat would be removed by a primary cooling loop (high-pressure steam or some sort of liquid metal) which would give the heat to a secondary steam loop (Rankine cycle) in a heat exchanger (steam generator). The steam would then turn a turbine, producing electricity, just like in a fission or coal power plant.
Of course, with a thermal process like a steam cycle, one is always limited by the Carnot efficiency, which increases as the temperature of the high-temperature reservoir goes up. So there are also designs to use a very high-temperature (800–1000 C) gas cooling loop and a Brayton cycle.
But the short answer is: the alpha power is captured by the plasma, and the neutron power is captured by the blanket. It all comes out as heat, which is used to heat a working fluid, which turns a turbine, producing electricity. This is not expected to be a technological problem – the challenge is in getting a confined thermonuclear plasma to produce the fusion energy in the first place!
19. Fusion Milestone Prizes?
by Baldrson
In 1992, with the assistance of fusion technologists such as Robert W. Bussard, I developed legislative language for a series of 12 milestones, each of which would be awarded a $(1992)100M prize for the achievement of objectives toward the attainment of practical fusion energy. This legislation also provided a grace period during which scientists and technologists that had been working on the US fusion program would be provided full salaries, without obligation, during which time they could seek support for their ideas to achieve these milestones. This legislation presaged a number of other prizes including the X-Prize and BAFAR / CATS prize. In 1995, Robert W. Bussard submitted this legislation to all relevant Congressional committees, copying all US plasma physics laboratories. Needless to say, the legislation wasn't passed. Do you think the time is right?
MIT Researchers: We think that the current approach, in which government-funded labs are not in direct competition, but have to justify their funding to the agency (in our case, the DOE), is the best option for the moment. Perhaps the X-PRIZE approach might work for the alternative concepts? (see our answer below regarding Polywell/Dense Plasma Focus/ IEC etc.)
20. ITER
by MpVpRb
Is the ITER project good science? Or is it a politically-motivated, pork-laden boondoggle?
MIT Researchers: ITER is absolutely good science. Governments representing over half the population of the world are backing the project because it is the logical next step – a prototype reactor that will produce ten times more fusion energy than heating power put in, for a few minutes at a time. It is also pushing forward the development of fusion reactor technology (materials, control systems, remote handling systems, etc.). The U.S. fusion community endorsed ITER as the best option for a next-step experiment at the Snowmass II conference in 2002 (see proceedings here).
All of that said, the cost of ITER has risen substantially from the original estimates, and because overall magnetic fusion funding has remained nearly flat in the United States, the U.S. contribution to ITER is threatening to swallow up the entire domestic program. This is starting with the planned closure of Alcator C-Mod in September 2012, but unless more money is allocated to fusion research, all three U.S. tokamak facilities are at risk in the next few years.
Graduate students at Alcator C-Mod have put together a web page explaining the problem: http://www.fusionfuture.org/faq/the-fusion-budget-problem/ and we urge you to go to this website and click the link to contact your member of Congress and urge them to fully fund a strong domestic program and the U.S. contribution to ITER!
21. NIF
by Grond
Is the NIF approach even plausibly capable of generating electricity in a useful way? Or is it purely a research platform / smokescreen for nuclear weapons research?
MIT Researchers: The primary mission of the National Ignition Facility (NIF) is "stockpile stewardship." That is, to ensure that U.S. nuclear weapons continue to be a credible deterrent. This is why NIF is funded by the National Nuclear Security Agency (the agency in charge of the nation’s nuclear stockpile), not the DOE Fusion Energy Sciences program. Thus, the weapons research mission of NIF is not a smokescreen, but is actually the publicly acknowledged primary objective for the facility.
Some researchers at NIF believe that their inertial fusion approach can be used for an energy source as well. We don’t want to speculate here on the plausibility of the LIFE (Laser Inertial Fusion Energy) concept. There is a National Academy of Science review of the prospects of inertial fusion energy under way right now; the final report is expected to be published before the end of this year.
18. Dense Plasma Focus
by mbradmoody
Do you see any merit in the "dense plasma focus" approach to commercial fusion power production, specifically the work of the Lawrenceville Plasma Physics group?
22. Focus Fusion / aneutronic fusion?
by mwk88
Focus Fusion Society is posting research on their project to do aneutronic (e.g. Proton Boron (pB11)) fusion. The concept sounds great, and as an engineer, I find several parts of their design, such as direct extraction of electric power, to be elegant. Is this credible research or pie-in-the-sky? I have not seen much mention of them in mainstream fusion research.
23. Polywell Fusion
by mknewman
What do you think of the efforts at EMC2 Fusion and Polywell Fusion? They seem to be making real, measurable, and open results, but the mainstream physics community seems to ignore this progress.
24. What’s wrong with IECs / Fusor?
by claytongulick
Why aren't IEC reactors based on Farnsworth's designs taken more seriously? From what I understand, IECs have been more effective at producing fusion, and they are cheap to build. People even build them in the garage. From everything I've read, no one really takes the "fusor" seriously in the fusion science realm, and it's considered a dead line of inquiry. I've never understood why.
MIT Researchers: These four questions (18, 22–24) are answered together here.
None of us are experts on inertial electrostatic confinement, magnetized target fusion / dense plasma focus, or Polywells, and so we don’t want to say too much about the specifics of those designs. We can say the following:
1. The amount of money that is being spent, especially in the United States, on fusion is far lower than the field deserves, given its track record and potential. This sounds self-serving, but we think it’s justifiable based on the facts. The graph we posted above shows how the fusion budget is far lower today than it was thirty years ago, even as we continue to make steady progress toward a reactor and the seriousness of the coupled energy/climate problem becomes more obvious.
The alternate confinement concepts program has also seen cuts. (“Alternative” in DOE Fusion Energy Sciences parlance means, basically, anything that isn’t tokamaks, stellarators, or laser [inertial] fusion.) The Levitated Dipole Experiment, an innovative magnetic-confinement arrangement based on planetary magnetic fields, was cancelled just as they were about to add significant auxiliary heating for the first time. And these small-scale alternative confinement projects are not very expensive! Some of these alternative concepts may very well be promising and deserve taxpayer money to be developed.
2. But on the other hand, these groups need to show that they deserve funding. It’s not enough to just tease these promising results and be secretive about the methods or technologies. Public funding can only come when the details are published in the open literature, and subjected to the scrutiny of peer review and the wider community reading the papers. The (hot) fusion community is still living with the aftermath of the cold fusion scandal from a quarter century ago - so it’s very important for the proponents of these alternate concepts to push the researchers to publish their results in peer-reviewed journals. Whatever negatives the tokamak might have, one thing you can’t say about it is that the research has been too secretive, and this has allowed the funding agencies to make the judgement that the tokamak is currently the most promising route to a fusion reactor, which is why this line of research gets the most money.Special thanks to Dr. Martin Greenwald, Prof. Ian Hutchinson, Asst. Prof. Anne White, Prof. Dennis Whyte, Nathan Howard, and Geoff Olynyk for taking the time to answer our questions.
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Gate One Brings Text-mode Surfing To the Web, Quake-Style
Riskable writes "As a follow-up to my previous Slashdot story, Gate One is now out of beta. Packages can be downloaded here. There's also a live demo: press the ESC key on this page to have a terminal running lynx drop into view, Quake-style! I've also posted a video overview and the documentation can be found here. Some pertinent changes since the beta: Added the ability display images inline within terminals, key-based SSH authentication, a WebSockets authentication API (for secure embedding), dramatically improved terminal emulation, an overhauled bookmark manager, support for international keyboard layouts, and a web-based log viewer that lets you export logs to self-contained HTML playback files." -
Ask Slashdot: Do Kids Still Take Interest In Programming For Its Own Sake?
nirgle writes "I have been wondering lately if there are any kids interested in programming for its own sake anymore. When I was my nephew's age, computers were still fascinating: There wasn't a laptop on every table, facebook wasn't splattered on every screen, and you couldn't get any question answered in just a couple seconds with Google. When I was 10, I would have done anything for a close programming mentor instead of the 5-foot high stack of books that I had to read cover-to-cover on my own. So I was happy when my nephew started asking about learning to do what "Uncle Jay does." Does the responsibility now shift to us to kindle early fires in computer science, or is programming now just another profession for the educational system to manage?" Another reader pointed out a related post on the Invent with Python blog titled "Nobody wants to learn how to program." -
Ask Slashdot: What Can You Do About SOPA and PIPA?
Wednesday is here, and with it sites around the internet are going under temporary blackout to protest two pieces of legislation currently making their way through the U.S. Congress: the Stop Online Piracy Act (SOPA) and the Protect-IP Act (PIPA). Wikipedia, reddit, the Free Software Foundation, Google, the Electronic Frontier Foundation, imgur, Mozilla, and many others have all made major changes to their sites or shut down altogether in protest. These sites, as well as technology experts (PDF) around the world and everyone here at Slashdot, think SOPA and PIPA pose unacceptable risks to freedom of speech and the uncensored nature of the internet. The purpose of the protests is to educate people — to let them know this legislation will damage websites you use and enjoy every day, despite being unrelated to the stated purpose of both bills. So, we ask you: what can you do to stop SOPA and PIPA? You may have heard the House has shelved SOPA, and that President Obama has pledged not to pass it as-is, but the MPAA and SOPA-sponsor Lamar Smith (R-TX) are trying to brush off the protests as a stunt, and Smith has announced markup for the bill will resume in February. Meanwhile, PIPA is still present in the Senate, and it remains a threat. Read on for more about why these bills are bad news, and how to contact your representative to let them know it.
Note: This will be the last story we post today until 6pm EST in protest of SOPA. Why is it bad?
The Stop Online Piracy Act is H.R.3261, and the Protect-IP Act is S.968.
The intent of both pieces of legislation is to combat online piracy, giving the Attorney General and the Department of Justice power to block domain name services and demand that links be stripped from sites not involved in piracy. The problem is that the legislation, as written, is vague and overly-broad. For one thing, it classifies internet sites as "foreign" or "domestic" based entirely on their domain name. A site hosted abroad like Wikileaks.org could be classified as "domestic" because the .org TLD is registered through a U.S. authority. By defining it as "domestic," Wikileaks would then fall under the jurisdiction of U.S. laws. Other provisions are worded even more poorly: in Section 103, SOPA lays out the definition for a "foreign infringing site" as one where "the owner or operator of such Internet site is committing or facilitating the commission of criminal violations punishable under [provisions relating to counterfeiting and copyright infringement]." The problematic word is facilitating, as it opens the door to condemning sites that simply link to other sites.
The most obvious implication of this is that search engines would suddenly be responsible for monitoring and policing everything they index. Google indexed its trillionth concurrent URL in 2008. Can you imagine how many people it would take to double check all of them for infringing content? But the job wouldn't end at simply looking at them — Google would have to continually monitor them. Google would also have to somehow keep track of the billions of new sites that spring up daily, many of which would be trying to avoid close scrutiny. Of course, it's an impossible task, so there would need to be automated solutions. Automation being imperfect, it would leave us with false positives. Or perhaps sites would need to be "approved" to be listed. Either way, we'd then be dealing with censorship on a massive scale, and the infringing sites themselves would continue to pop up.
But the problems don't end there; in fact, SOPA defines "Internet search engine" as a service that "searches, crawls, categorizes, or indexes information or Web sites available elsewhere on the Internet" and links to them. That's pretty much what we do here at Slashdot. It's also something the fine folks at Wikipedia and reddit do on a regular basis. The strength of all three sites is that they're heavily dependent on user-generated content. Every day at Slashdot, readers deposit hundreds and hundreds of links into our submissions bin. Thousands of comments are made daily. We have a system to surface the good content, but the chaff still exists. If we suddenly had a mandate to retroactively filter out all the links to potentially copyright-infringing sites in our database, we wouldn't have many options. We're talking about reviewing hundreds of thousands of submissions, and every comment on 117,000+ stories. And we're far from the biggest site around — imagine social networks needing to police their content, and all the privacy issues that would raise.
Small sites and new sites would be hurt, too. A website isn't a single, discrete entity that exists on its own. A new company starting up a site would have to worry about its webhost, registrar, content provider, ISP, etc. The legislation would also raise significant financial obstacles. New companies need investments, and that would be much less likely (PDF) if the company could be held liable for content uploaded by users. On top of that, if the site was unable to live up to the vague standards set by the government and the entertainment industry, they could be on the receiving end of a lawsuit, which would be expensive to fight even if they won (and such laws would never, ever be abused). It's hard to conceptualize the internet without noting its unrivaled growth, and SOPA/PIPA would surely stifle it.
This legislation hits near and dear to the hearts of many Slashdotters; if SOPA/PIPA pass, IT staff for companies small and large are going to have their hands full making sure they aren't opening themselves to legal action or government intervention. Mailing lists, used commonly and extensively among open source software projects, would be endangered. Code repositories would need be scoured for infringing content; the bill allows for the strangling of revenue sources if its anti-infringement rules aren't being met. VPN and proxy services become only questionably legal. The very nature of the open source community — as the EFF puts it, "decentralized, voluntary, international" — is not compatible with the burdens placed on internet sites by SOPA and PIPA.
What can we do?
So, what can we do about it? There are two big things: contact your representative, and spread the word. Slashdot readers, on the whole, are more technically-minded than the average internet user, so you're all in a position to share your wisdom with the less internet-savvy people in your life, and get them to contact their representative, too. Here's some useful information for doing so:
Propublica has a list of all SOPA/PIPA supporters and opponents.
Here is the Senate contact list and the House contact list.
You can also use the EFF's form-letter, the Stop American Censorship form-letter, or sign Google's petition.
If you don't live in the U.S., you can petition the State Department. (And yes, you have a dog in this fight.)
SOPAStrike has a list of companies participating in the protest, and this crowd-sourced Google Doc tracks companies that support the legislation. Tell those companies what you think.
Further reading: Wikipedia has left their SOPA and PIPA pages up. The EFF has a series of articles explaining in more depth what is wrong with the bills. Here are some protest letters written to Congress from human rights groups, law professors, and internet companies.
Go forth and educate. -
Leaked Memo Says Apple Provides Backdoor To Governments
Voline writes "In a tweet early this morning, cybersecurity researcher Christopher Soghoian pointed to an internal memo of India's Military Intelligence that has been liberated by hackers and posted on the Net. The memo suggests that, "in exchange for the Indian market presence" mobile device manufacturers, including RIM, Nokia, and Apple (collectively defined in the document as "RINOA") have agreed to provide backdoor access on their devices. The Indian government then "utilized backdoors provided by RINOA" to intercept internal emails of the U.S.-China Economic and Security Review Commission, a U.S. government body with a mandate to monitor, investigate and report to Congress on 'the national security implications of the bilateral trade and economic relationship' between the U.S. and China. Manan Kakkar, an Indian blogger for ZDNet, has also picked up the story and writes that it may be the fruits of an earlier hack of Symantec. If Apple is providing governments with a backdoor to iOS, can we assume that they have also done so with Mac OS X?" -
Prepare For Massive Wave of Earthquake Scams
wiredmikey sends this quote from Security Week: "Today's tragic events of the 8.9 magnitude earthquake and resulting tsunami, as sad as it is, is a dream for scammers and fraudsters around the world. Tragic events are always something scammers use to their advantage, helping them prey on and exploit innocent victims. Scams are already spreading across Facebook, which started in a matter of minutes after the news broke of the earthquake in Japan. As I write this, scammers are hard at work, registering new domains and cranking out templates for their fake donation sites. This will be followed with massive volumes of email spam, Tweets through Twitter, and Facebook posts, as scammers gear up to solicit donations from around the world." As coverage of the earthquake and resulting tsunami has proceeded, collections of videos and pictures are showing the extent of the devastation. The NY Times makes the excellent point that things could have been much worse if not for building codes and quake-resistant engineering. A state of emergency was declared at one of Japan's nuclear plants, after the earthquake caused cooling problems at one of the reactors. No radiation leakage has been reported, and the US Air Force has helped by delivering coolant by air. -
Anonymous Now Attacking Corporate Fax Machines
An anonymous reader writes "Anonymous has claimed responsibility for distributed denial of service attacks against several anti-WikiLeaks websites this month. In a novel twist to the campaign, Mission Leakflood has started a new DDoS attack against fax numbers belonging to Amazon, MasterCard, Moneybookers, PayPal, Visa and Tableau Software. Some numbers have already stopped responding, and Twitter and PostFinance have since been added to the target list." -
Onion Story Gets Blown Out of Proportion
A 3-year-old Onion video titled "Martial Law Plans Revealed?" has swept across the internet recently, and taken the gullible along with it. The video has some preaching from the highest mountain top about the evils of a government turning fascist, and an equal number explaining until red in the face what The Onion is. -
Parasite Correlated With World Cup Success
mahiskali writes "A parasite commonly found in cats, Toxoplasma gondii, has an unnerving relation to World Cup victories by country. (This parasite was discussed here twice in 2006.) Toxo can be found in almost every type of mammal, from rats to humans. The overall goal of the parasite is to end up in a feline stomach, which is the only place it can reproduce. In other mammals, humans for example, the parasite heads for the brain. It is estimated that nearly 1/3 of the human population has a latent Toxo infection, with individual countries having infection rates varying from 6% (Korea) to 92% (Ghana). Countries with greater incidence of this parasitic infection in their populations tend to win more World Cups than those without. The article, written by a Stanford University neuroscientist, goes on to try out various rationales for such a correlation, ranging from increased testosterone to increased dissent of authority — all symptoms of a Toxo infection. Now we just need to find a parasite that causes an inability to referee properly, and we'll have this whole World Cup business all sorted out."