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Comment: Color means many things (Score 2) 327

by ganv (#49153205) Attached to: Is That Dress White and Gold Or Blue and Black?
This reminds me of the great entries from the competitaion to explain 'What is Color':

https://vimeo.com/87968614 http://www.centerforcommunicat...

By the way, I see white/lavender and brown. It would be very interesting to know what lighting/image manipulation was done to get those colors out of a dark blue and black dress.

Comment: Is NIH unique here? (Score 1) 153

by ganv (#48778295) Attached to: Fewer Grants For Young Researchers Causing Brain Drain In Academia
In the physics and engineering proposals I have reviewed, it seems that young researchers still get a significant preference in the distribution of grants. But there is a problem that the proposals from young researchers are often much weaker. It is really hard to write a great grant proposal and new faculty members usually struggle long and hard to get good at it. You have to have great ideas, preliminary work, and a great presentation. And you have to know how to market your ideas to the diverse set of people who will be reviewing the proposal. Maybe 30 years ago, people could get research grants just by describing some potentially interesting research, but in the current environment, you have to write a proposal that is better than 80 or 90% of the others, and that is hard for young people to do. Maybe the bias toward younger researchers should be stronger. But I don't think it helps them to set a low bar and then they will fail to get their grants renewed. I would recommend that grant agencies more aggressively limit the number of grants that can be accumulated by the big names. No one can effectively mentor 5 post-docs and 10 graduate students, and letting them suck up all the funding just because they are able to spit out a large number of strong proposals limits the number of new researchers who can be funded.

Comment: Re:A Word to the young bright kids out there (Score 2, Interesting) 153

by ganv (#48778101) Attached to: Fewer Grants For Young Researchers Causing Brain Drain In Academia
That advice makes sense. It will be very hard to implement though. Research grants pay graduate student stipends. I am not sure it is a subsidy. It is the way research work is paid for. The problem is that the work is done for depressed wages: the typical accomplishments of a grad student are much much larger than you could get with a similar salary offered to a non-degree seeking researcher, same thing for post-docs: they are paid less with the hope that they are preparing for a step up to a permanent position soon. So implementing your system is going to make research much more expensive to perform. If there are fewer graduate students doing research, then research becomes even more a winner take all because only the top professors will be able to support graduate students and maintain active research programs. That means even fewer faculty positions (without research funding, universities hire fewer faculty who teach more rather than more faculty who are also doing research). I think a better fix is to adjust the graduate programs so that they focus not on creating future researchers, but on creating experts prepared for a wide range of technical jobs that are not in research. Research would become a smaller part of these graduate programs and only the top few students who wanted to pursue a research career would continue for post-doctoral research.

Comment: Re:Why is he worried (Score 1) 583

by ganv (#48247209) Attached to: Elon Musk Warns Against Unleashing Artificial Intelligence "Demon"

I think Elon sees something that most of you do not. Artificial intelligence is not like anything else. We know very very little about the kinds of intelligence that are possible. But if it is possible to build AI that is smarter and more capable than us, then it will by definition be better than us at building the next generation of itself. And at that point, humans are permanently obsolete because we have no rapid methods for upgrading ourselves. It has nothing to do with who is 'using the AI' or 'Who is doing the prescription'. There will be no person and no human moral intuitions in the loop at all. The intelligence that supersedes us will be doing what it wants to do. We'll be like the fish who debate how to control their bipedal relatives who have decided to start overfishing the oceans. It is simply out of their control. And if that doesn't scare you, then you don't understand.

We don't know whether or not artificial intelligence is possible. But it seems like a very reasonable possibility sometime in the next few centuries. And we know so little about intelligence that we have very little idea about whether it will share anything like the moral intuitions that undergird human society. Many of us suspect those evolved for survival in hunter-gatherer tribes and AI will evolve a very different set of criteria upon which it makes its choices.

Comment: Re:Wrong distance away (Score 3, Informative) 23

by ganv (#48208985) Attached to: Two Exocomet Families Found Around Baby Star System
That error jumped out to me also. Its like describing a city 93 miles away and instead saying it is 93 million miles away which instead of being 1.5 hour drive is all the way to the sun. It is really useful to get a cosmic distance scale in your head: billions of light years is the size of the visible universe, millions of light years are distances to nearby galaxies. 30,000 light years is the distance to the center of our galaxy. 4 light years is the distance to the nearest stars.

Comment: Re:Amusing (Score 1) 350

by ganv (#48174057) Attached to: The Physics of Why Cold Fusion Isn't Real
We just discovered that we are made of atoms a little over one century ago, and our ignorance is vast. But we should also be careful not to err on the side of blindly assuming that anything is possible. It is essential to think clearly about what might and might not be possible based on what we know now in order to direct our investigations. Will we discover new laws of physics that are relevant to releasing energy from nuclear reactions? I suspect the answer to that is probably no, and the reason is the high precision we achieve from our current theories in describing the behavior of atoms and nuclei. Careful experiments of nuclear excitation energies, fusion cross sections, etc agree with theoretical calculations, often to many significant digits. There just isn't much place to hide new physics in this energy range. Of course new fundamental discoveries (dark matter, etc) are very likely. They just are unlikely to change our predictions for nuclear phenomena by a quantitatively significant amount. Would it be better to stay open minded because one can never be sure? (See http://www.preposterousunivers...) Or is it better to make audacious, falsifiable hypotheses, such as the hypothesis that we already know the laws underlying the physics of everyday life? (http://www.preposterousuniverse.com/blog/2010/09/23/the-laws-underlying-the-physics-of-everyday-life-are-completely-understood/)

That doesn't tell us much about how to engineer processes that obey the known laws of physics. Predicting what humans will be able to do is very very difficult...and people regularly get it badly wrong being both too optimistic and too pessimistic. In my mind, good hypotheses based on careful consideration of the best evidence are never premature. They just might be wrong.

Comment: Re:Useful but physics? (Score 1) 243

by ganv (#48126317) Attached to: 2014 Nobel Prize In Physics Awarded To the Inventors of the Blue LED
You imply that if string theory and fundamental particle physics must have practical relevance like the quantum theories of atomic and nuclear physics of 100 years ago. But they are dramatically different. At that point, they didn't understand what matter was made of. (And despite a few notorious quotes, the best scientists knew that they didn't know how to explain atoms and chemistry.) Now we can't find anything in our galaxy that deviates from our current theories. There just are not going to be any practical applications of the Higgs boson or dark energy (at least not for many thousands of years...). If you are among those who think that physics is discovering new fundamental laws and engineering is using those laws to understand and control phenomena that we care about, then your version of physics is ceasing to be relevant. Instead, physics is actually the attempt to explain and control the world we live in using our knowledge of the fundamental laws. That kind of physics is slowly taking over all of science and engineering.

Comment: Re:Useful but physics? (Score 2) 243

by ganv (#48085241) Attached to: 2014 Nobel Prize In Physics Awarded To the Inventors of the Blue LED
Maybe we can try to help those ignorant of applied physics, but you may be right that they are hard to help...

There is a fantasy that lives on and on that physics is only the search for the fundamental rules of how the universe works. Physics does include the search for the most fundamental theory...things like trying to detect the higgs boson or understand dark energy. But those two pretty nicely define 'irrelevance' to the everyday lives of humans. If physics is only about the search for fundamental rules, then physics is essentially over as an enterprise with practical relevance. (See http://www.preposterousunivers...) But the overwhelming majority of physicists have long been working on applications of known fundamental physics to discover new emergent laws and new technological applications. Semiconductor and device physics is one of the great successes of 20th century physics and this achievement of fabricating gallium nitride with its large bandgap was a major advance, both in the fundamental science of crystal growth and in high frequency electronics as well as the production of blue light. This is exactly the kind of prize that should be given because we need the next generation of physicists to be finding fundamental problems that have practical relevance rather than using their talents on interesting but economically useless tasks like string theory. I predict that in the rest of the 21st cenury, there will be more Nobel prizes in physics given for biological, environmental, and neuroscience applications of physics than there will be for fundamental particle physics. If not, then the Nobel prize will be overshadowed by the Kavli prize or some other prize that recognizes accomplishments that have consequences for humans.

Comment: Propose the risky ideas after you demonstrate them (Score 1) 348

by ganv (#47877191) Attached to: When Scientists Give Up
"The reviewers who decide which projects receive funding are risk-averse."

This hasn't been my experience. Reviewers and grant officers want to fund high risk/high reward science. But you are competing with others who have already tried a bunch of risky ideas and are only proposing the ones that happened to work. You basically have to make a significant discovery before you can be funded and then you can get funding to bring that idea to full bloom and hopefully fund a few risky projects on the side that will serve as the basis of the next grant proposal.

Most new ideas are bad ideas, so funding agencies have to have a pretty rigorous filter to sort out the promising ones. As a result, it will always be very hard to get funding to explore an idea before there is evidence that it is on the right track.

Comment: Re:Why did they have to study this? (Score 1) 710

by ganv (#47456245) Attached to: People Who Claim To Worry About Climate Change Don't Cut Energy Use
Individual choices to conserve resources are well known to be ineffective. Improvements in energy efficiency are also ineffective. Look up Jevon's paradox. Individual conservation mostly decreases the price of fuels which encourages others to use more. The main rational reason for an individual to decrease their energy usage is build the knowledge base and cultural values of conservation that can serve as a foundation for eventual society wide action. I know the libertarians are unable to think clearly about this subject, but there is simply no way to manage common resources like the atmosphere, rivers, and oceans without holding all polluters accountable for the pollution they emit.

Comment: Re:Gigawatts per hour (Score 2) 461

by ganv (#47316633) Attached to: Half of Germany's Power Supplied By Solar, Briefly
Good to see I wasn't the only one who noticed the bad units. :) For those who missed it: Power is measured in Watts, which is energy per unit time (J/s). If you have 22 GW/hr, that is a rate of increase of power provided, so AvitarX calculated that after only 24 hours they would have 22*24=528 GW of solar power being produced, which is ridiculous, but that is what the post indicates.

Comment: sounds like Wall street business as usual (Score 2) 382

by ganv (#47175113) Attached to: High Frequency Trading and Finance's Race To Irrelevance
We have been for a long time in the situation where the financial institutions are primarily extracting rents from producers rather that contributing to economic productivity. High frequency trading is simply a particularly obvious example of this. The situation is not particularly new. Those with wealth and power have always influenced the rules to their own benefit. The question is whether there are any counter-measures that effectively push people to contribute value rather than skim off value created by others.

Comment: Re:The brain has multiple neural nets (Score 4, Interesting) 230

by ganv (#47098975) Attached to: The Flaw Lurking In Every Deep Neural Net

Your model of the brain as multiple neural nets and a voter is a good and useful simplification. I think we still know relatively little about how accurate it is. You would expect evolution to have optimized the brain to avoid blind spots that threatened survival, and redundancy makes sense as a way to do this.

However, I wouldn't classify blind spots as 'no problem whatsoever'. If the simple model of multiple neural nets and a voter is a good one, then there will be cases where several nets give errors and the conclusion is wrong. Knowing what kinds of errors are produced after what kind of training is critical to understanding when a redundant system will fail. In the end though, I suspect that the brain is quite a bit more complicated that a collection of the neural nets like those this research is working with.

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