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User: joe_frisch

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  1. Re:And in other news on Study: Science Still Seen As a Male Profession · · Score: 1

    The question is *why* more men than women want a career in science (if that is true).

    Is it due to some innate biological difference? Is it due to discrimination or harassment when they try to enter science? Is it due to a wide range of subtle societal pressures that are difficult to quantify?

    I think the best we can do is to look for and eliminate any detectable discrimination and try to ensure that women have the same opportunities as men.

    One thing to do is to study why the ratio of men to women is quite different in different technical fields.

  2. Re:I was working at IBM at the time on 25 Years Today - Windows 3.0 · · Score: 1

    I was an OS/2 user for a while. The problem I found was that major applications (like Lotus123) were more expensive on OS/2 and were often older variants. Since OS/2 had a windows compatibility mode I used that to use cheaper / newer apps. The compatibility mode seemed no more stable than windows itself (not really surprising). so I eventually decided running OS/2 was just an affectation and went back to windows.

    By the time OS2 came out, IBM just didn't have the muscle to drive the entire market anymore. I suspect it would have also died if it did not have a compatibility mode, but I think windows compatibility doomed it for sure.

  3. How does this work?
    Hackers claim they have a huge database of embarrassing information. How do they prove that they didn't simply invent the information?

    I have a "database" showing that Senator XYX has as thing for furries and garden implements. See - here I have a text file with Senator XYZ's name and a list of preferences......

    You could take any list of names and add arbitrary kinks, then threaten to release them. How do you show that this is the *real* database and not one you made up?

  4. Re:Death is too much publicity on Dzhokhar Tsarnaev Gets Death Penalty In Boston Marathon Bombing · · Score: 1

    But that isn't how we execute people. We spend millions of dollars and pay to keep them in prison for many years. In the end it can be more expensive than a life sentence.

  5. Death is too much publicity on Dzhokhar Tsarnaev Gets Death Penalty In Boston Marathon Bombing · · Score: 1

    He is a murderer and some will say he deserves to die. But - a death sentence will keep his name in the news for a long time. Better that he be locked up and forgotten.

    Personally I do not support the death penalty. It is too rare to be a deterrent. Too irreversible if there is a mistake. Too barbaric for a civilized society.

  6. Re:The real question is - on Dawn Spacecraft Gets a Better Look At Ceres' Bizarre 'White Spots' · · Score: 1

    No, they checked. In the video you can see it goes dim then black when it gets out of sunlight.

    It was worth checking though.....

  7. That is why I go by rail not air in Europe China, Japan, Korea - even though it is often more expensive than air.

    The key will be whether we can avoid the PITA issues in California HSR. If they want TSA, cheked luggage, 1 hour prior check-in and advanced reserved seats for reasonable prices, then I'll just fly. The flight itself is so short that the discomfort really isn't an issue. Its all the end effects that matter.

  8. Re:This again? on New Test Supports NASA's Controversial EM Drive · · Score: 1

    There are still a lot of ways for the experiment to get the wrong result in vacuum. The force is really quite tiny.

    Their "hard" vacuum was 1e-6 torr scale. That might still be enough to to produce some force. There can be effects from temperature causing anomolus forces in the suspension mechanism. There can be magnetic field effects from power cables. Torque from RF cables getting warm.

    This would be a very difficult experiment to do correctly. Without details, it is much more likely that they got it wrong, than that they have found a violation of conservation of momentum.

    As an aside, quantum mechanics still conserves energy and momentum. The pushing on virtual particles from the vacuum doesn't work unless you add enough energy to turn them into real particles - and then you just have a photon drive variant (which would produce far less thrust).

  9. Re:Enough of this on Long Uptime Makes Boeing 787 Lose Electrical Power · · Score: 2

    Even though this bug isn't a direct threat, it could interact with other future software changes. If it is a counter overflow there is a risk that the counter would run at a higher rate in some future version where more functionality is needed. If 248 days went to 2.48 days, it might not be caught in testing, but could (rarely) happen in real life.

  10. Re:Science requires a certain agnosticism on New Test Supports NASA's Controversial EM Drive · · Score: 2

    There is an old saying that you should keep your mind open, but not so open that your brains leak out.

    When someone claims a violation of very well tested physical laws, AND that violation is not under some new unusual condition, it is very reasonable to be skeptical.

    It this was seen with TeV protons at LHC, or in ultra-strong electric fields, or in strong gravity, or other unusual conditions it would be different. Physicists paid attention to the (later dis-proven) FTL neutrinos from CERN because that experiment was a new measurement under different conditions (very high energy neutrinos). We all expected (correctly as it turned out) that the effect was an instrumentation error, but we paid a lot of attention because it was possibly it was something extraordinary. This isn't.

  11. Re:This again? on New Test Supports NASA's Controversial EM Drive · · Score: 1

    I have spent my life (or at least 35 years) studying physics and doing experiments, many of which include high power microwaves.

    There are a lot of ways for them to have gotten this wrong, and it violates very fundamental physics principals. They can publish in a refereed journal with enough details to satisfy other physicists if they really have something.

  12. Re:This again? on New Test Supports NASA's Controversial EM Drive · · Score: 1

    If you use energy to create real particles out of virtual ones, you are building something very like a photon drive. Its just like an LED converting electricity to matter (photons). Those photons produce thrust - but the thrust / power is extremely tiny. This limit applies to any sort of particles you might produce.

  13. Re:This again? on New Test Supports NASA's Controversial EM Drive · · Score: 1

    There are a number of concepts for accelerator driven nuclear reactors. Nothing fundamentally crazy, just none have been made practical yet. I don't know if there is enough room to increase the efficiency of generating and collecting neutrons - it may be that you just can't quite get there. Similar situation to muon catalyzed fusion. It *almost* works, but the muons stick to the helium after it is formed and you can't quite come up with a scheme where it is a net energy producer.

    Theses sorts of concepts are being looked at - they may eventually get one to be practical, but so far no.

  14. Difficult experiment, clearly wrong . on New Test Supports NASA's Controversial EM Drive · · Score: 4, Informative

    Its not easy to measure 50 micro-newtons of force when you change a power level by 50 watts.

    Currents cause magnetic forces. Things get hot and outgas producing thrust. RF power cables get hot and distort causing a force.

    Think about it. The device weighs something like 5Kilos. That is 50 newtons gravitational force. So a 1 micro-radian tilt will cause a 50 micro-newton force. Walking across the lab floor could cause that amount of deflection. If the chamber is 1 meter across, a 0.1 degree temperature change on one side of the chamber (from a nearby power supply) could cause that much tilt.

    There of course could be force just from photons - but that is a simple and well understood photon drive - known for at least 50 years now - basically a light-sail.

    This is a very difficult experiment to do correctly, and they have not published in enough detail.

    Meanwhile: conservation of momentum has been tested under conditions ranging from ultra-cold gas atoms to 100GeV particle collisions, to orbiting neutron stars. The RF fields they use are very modest. At SLAC we run hundreds of megawatts, not 50 watts. We have superconducting cavities where we easily see the deflection caused by the momentum in the microwave fields - operating at many thousands of times higher power than this experiment - we see nothing unexpected.

    So: Difficult experiment. No unusual physical conditions. Apparent violation of one of the most carefully tested conservation laws in all of science.

    It it literally more likely that the sun will not rise tomorrow (since that is also based on conservation of momentum) than that this experiment was correct.

  15. Re:The best encryption: No encryption on Allegation: Philly Cops Leaned Suspect Over Balcony To Obtain Password · · Score: 1

    It is quite possible to demand keys that someone *thinks* might be there. More is the pity if there never was any encrypted data on the device to begin with.

    A lot of misbehavior from law enforcement seems to stem from them being "sure" of what is going on, despite a lack of evidence to support the surety.

  16. Re:Help me out here a little... on Utilities Battle Homeowners Over Solar Power · · Score: 1

    Sure. But if a higher percentage of customers are using solar, then the utility is selling less power so there is less money available to support the infrastructure. They can either increase prices on the non-solar customers, or decrease the amount of money they pay when solar is put back on the grid.

    If you do the former, at some point the price gets high enough that everyone is forced into local power generation - a sort of asymptomatic run-away. That may be OK, but once its done, no one is paying for infrastructure.

  17. Re:Help me out here a little... on Utilities Battle Homeowners Over Solar Power · · Score: 1

    There are a number of ways the utilities could handle this, but they cost money. Someone has to cover the cost of the new equipment.

  18. Re:Sort of redundant on Public Records Request Returns 4.6M License Plate Scans From Oakland PD · · Score: 3, Interesting

    The risk of large scale surveillance is that it can generate data sets that can be mined for information. Tracking can show networks of friends, attendance at political rallies, books read, movies watched, foods and alcohol consumed. Does this pattern match for a potential terrorist - can't prove anything, but maybe you shouldn't keep your job at Lockheed, or should get extra screening at the airport? Did you watch "little miss sunshine" too many times for your demographic - could mean you are a pedophile - maybe you shouldn't have a job as a school teacher - think of the children.

    Which political information should you see? Candidates can target their adds to YOU specifically. Same for news, and advertising.

    Maybe you don't get enough sleep, or are found to meet women ( or other men) at bars and take them home. Sounds like "statistically" you might be a health risk and your insurance rates will go up.

    Large scale tracking, data collection and analysis allow for statistical pattern matches. The public might be happy that a new system has a only 1% failure rate, and only a 10% false positive rate for recognizing people who are a danger to children - unless you are in that 10%

  19. Mars one claims $6B to put 4 people on mars.
    On one side -how do they plan to raise that amount of money? They use the Olympics as an example,but that is an event with an enormous viewership. Are they claiming they can get anything like a similar number of viewers for a bunch of guys living (or slowly dying) on mars?

    On the other side, what technology do they have that makes a mars mission cost $6B, not the hundreds of billions that NASA estimates? Sure they may be able to do for somewhat less money, but a factor of 100??? Where is their demonstration of technical expertise to support such a claim?

    Its just a scam.

  20. Re:Nice - If you can do it on Full-Duplex Radio Integrated Circuit Could Double Radio Frequency Data Capacity · · Score: 1

    I use them regularly. They are usually only good to 20-30dB. You can make the transmit and receive antennas *mostly* not couple to each other, but it will be very difficult to get the isolation you need .

  21. Doesn't matter on Ask Slashdot: Choosing a Laptop To Support Physics Research? · · Score: 2

    I'm a career physicist, and I regularly take college interns. She can use whatever she is comfortable with. I I need my interns to have some particular computer or software I will get it for them.

    Personal computers in physics are mostly for writing reports and quick calculations. High power computation and data analysis is done on dedicated server farms.The personal computer is just used as a terminal.

  22. Re:Consistency on World's Most Powerful Laser Diode Arrays Deployed · · Score: 4, Interesting

    the pump is probably 3.2MW for a long pulse (100s of microseconds), and the output is petawatts for a short time (femtoseconds).Diodes are often used to pump solid state laser materials that store energy for many microseconds, then release it much more quickly. (along with chirp pulse amplification to get even larger power compression).

  23. Re:Another diploma mill with a marketing team on Inside Minerva, a Silicon Valley Bid To Start an Elite College Online · · Score: 4, Insightful

    Another major difference between colleges is the interaction with other students. For example at Caltech you are in an environment where it is normal to study for a few hours every night, and where scientific discussions are common, you will get more mental exercise and learn more. An elite liberal arts school will likely provide equivalent benefits.

    Then, while less "pure", the contact you make at an elite school are very valuable in your future career .

  24. Re:Of course they are on It's Official: NSA Spying Is Hurting the US Tech Economy · · Score: 1

    And this is why its so sad that the NSA did this. The US could have grabbed a lot of the market if we could have assured users that our equipment was trustworthy. It would have taken some time, but eventually we would have grabbed market share from China. Now that everyone assumes both countries are spying on their hardware, we no longer have that competitive advantage.

  25. Re:Another rumor ... on TrueCrypt Audit Back On Track After Silence and Uncertainty · · Score: 1

    Once trust is lost, you can't get it back. There is no way to trust the people who are telling you to trust the audit. NSA *could* be anywhere. That doesn't mean that they ARE anywhere, but I can't see any way to trust any software or audit process. (unless you are one of the extremely rare people who can personally audit the code).

    If you had a piece of code that *you* knew was completely secure, how could you convince me of that?