What does it take to specify the state of a car? Many would claim that the dimensions of all parts and the material properties of the alloys and composites is a pretty complete description. You don't need all the modern physics. You just need a model that is quantitatively adequate for the level of accuracy desired. Simulating the classical/solid mechanics of a full auto crash is still a bit beyond us, but we can simulate many parts of the process. Even before simulation, we developed an understanding that allowed major improvements in auto safety that was partly rooted in approximate theories and partly in phenomenology. That distinction between an approximate theory (classical mechanics plus solid mechanics) and a phenomenology (observing auto crashes and drawing conclusions about what the important processes must be) is very important. With human interactions, we have many pieces of phenomenology (some pretty complicated parts of this are taught as 'social skills' in pre-school). But we have nothing in the way of a theory whose approximations are understood and whose predictive power goes beyond the situations from which the phenomenology was derived. I would argue that predictions in social engineering are essentially extrapolations of phenomenology that might work and might not...you simply don't know until you do the experiment. Whereas in classical mechanics, you know much more about what is going to happen including the Lyapunov exponents for chaotic systems that tell you when your predictions will no longer be accurate.
Your last comment is about political control. You seem to mean that our phenomenology will improve as big data mines human behavior and we learn to use that data and those ideas to control others. We do need to be careful who controls that. Although I suspect that the degree of control achievable by such means is easy to overestimate.
This hope for an effective theory of human behavior is a reasonable hope. There might be a simple effective model that could describe human behavior without accounting for all of the parameters needed to fully specify the problem. It happens in many fields. We can very accurately predict fluid flows without worrying about the parameters of all the molecules. But for humans, it really is hard to imaging how it might work out. Consider the fact that once some humans have a theory of how humans behave, someone will start using it to gain a competitive advantage and then other people will start changing their behavior in response to knowledge that the theory is being used. It is a fascinating way to be unknowable...to be guaranteed to change as soon as anyone figures it out.
"Social scientists will be able to understand and predict the interactions of people the way physicists understand and predict the interactions of objects."
Many of us technical types would love for this line of inquiry to be fruitful. But to have a 'physics of people' you have to know the values of all the parameters needed to specify the current state of a person and you need to know all interactions of that person with the rest of the universe. Phrased like that you can see how ludicrous it is to dream of using the methods of physics for social science. Physics works because the fundamental constituents of the universe happen to be only a small number of particles whose interactions are amazingly simple. For example all electrons are exactly identical and interact via only 3 forces (with some uncertainties about effects on scales larger than galaxies and energies higher than trillions of electron volts). The hope for a theory of sociology is a false hope. The hope for a useful phenomenology might be more reasonable and big data can help.
With inflation and continued erosion of social security and other retirement income sources other than assets, my calculations say that I simply can't retire with a middle class income if I don't have quite a bit more than $1 million in 2040 when I retire. Real returns are below 5% these days, and $1million kicks off less than $50,000 per year which will likely be well below median in 2040. As others have noted, it is not all that hard to reach $1 million with regular investing and modest real returns (and assuming we don't have a market collapse which is not an entirely justified assumption). But it is a system that a large number of numerically handicapped Americans seem not to be able to plan for or cope with. I would translate the headline: "44% of US developers don't think they are going to be able to retire (or simply have never done the math)".
Not sure what you mean there. Quantum mechanics is hugely important for everyday life--all the biochemistry of life is quantum mechanics. So the ability to build a quantum computer would be expected to open up vast new possibilities. But that will function on the basis of known physics. My comments about the limited engineering uses of quantum mechanics so far was meant to point out how it is easy to overestimate the practical use of fundamental theories even when the theories describe all the matter around us. The question at hand is whether unknown physics (dark matter, undiscovered particles, etc) affects everyday life or will have a practical impact on technology. If it does, it will probably be in applications that involve precision measurement where you need 15 digits of accuracy so that Feynman diagrams including particles beyond the standard model become important.
It might have been better if I had phrased (2) a little more strongly like Carroll did: something like 'the physics of everyday life is completely understood' or 'there will be no practical applications of physics beyond our current theories (the standard model and general relativity)'.
Yes they might be compatible. But if (2) is true, then the discoveries of (1) quickly become irrelevant. This is what Horgan is getting at. If new theoretical ideas don't have any practical implications for our corner of the milky way galaxy, it is going to become very very hard to keep up a never ending sequence of experimentally confirmed discoveries.
Note that Carroll was not claiming that Newtonian mechanics explained all of everyday life. He was claiming that the standard model plus general relativity contained all of everyday life. The analogy to Newtonian mechanics is to help people see how little impact on everyday engineering practice even the discovery of quantum mechanics had (and QM is a hugely practical theory that explains materials, semi-conductors, etc as you note). My guess is that the quantitative discrepancies between current predictions and measurements leave little hope that discoveries beyond the standard model and GR are going to have any practical applications except maybe in the distant future if we need 15 digits in the magnetic dipole moment of the muon or are trying to travel outside our galaxy or are considering the heat death of the universe. Like Horgan, I would love to be wrong. But I just haven't heard any good empirical arguments to support claim (1) that are deeper than 'past performance predicts future results' mixed up with wishful thinking.
The mercury/Vulcan reference is an interesting one. Note that the precession of Mercury is a pretty small effect and the GR effects that produce it have only recently begun to have practical applications in the global positioning system clocks. Do you have modern candidates to propose where unobserved entities are hypothesized to patch up measurements with the standard model or GR? Dark matter and Dark energy are the obvious candidates. The Higgs particle also could have been such a thing. If it had not been observed we might have needed a paradigm shift, but even that probably would not have made much practical difference. You don't need to be able to predict the masses of the particles in the standard model for practical purposes. It works quite well to measure their properties and use that to predict how they behave.
A 19th century analogy is to chemistry. Chemists in the late 19th century were able to put in place much of modern chemistry without having correct ideas about how a chemical bond actually worked. Quantum physics did not replace chemistry. It mostly explained things that were already known. But it did something else...it suggested where to look for new discoveries: the addition of Hafnium to the periodic table for example. It also opened up precision calculations of bond energies, bond lengths, etc which have been quite useful. That is what happened when we finally figured out how ordinary matter works...the stuff we are made of. (1) is a guess that figuring out what dark matter is or the properties of possible non standard model particles formed at energies above 100GeV will guide us to new areas of inquiry that lead to breakthroughs and practical applications. But it seems an unsupported guess. We already have discoveries like the top quarks and tau neutrino that didn't lead to any significant breakthroughs or new technology. Does anyone have any dark matter hypotheses for which they have a potential application? It is just very hard to imagine what one could do with a source of gravitational force that interacts so weakly with ordinary matter than it is currently only detectable on length scales of an entire galaxy. And dark energy is much much farther from engineering use.
So let's keep trying to find new breakthroughs. But it is also good to be honest with ourselves about what we have reasons to expect and what is wishful thinking.
The subject of the likelihood of future breakthroughs in basic science is very important. But Horgan is not very good at articulating the main issues. Much better is Sean Carroll's blog: http://www.preposterousunivers...
To simplify the situation to make it comprehensible, consider two hypotheses about the future of science. (1) Science will have an eternal sequence of groundbreaking discoveries/paradigm shifts. (2) The highly successful models we currently use are so accurate that they will continue to be used forever.
The first hypothesis is beloved by scientists in search of funding and by sociologists of science who wish to treat science as merely a social construct. It really is a strange alliance, but a common cause can make strange bedfellows. The second hypothesis is much less widely defended. Partly because it is clearly false in a fundamental sense...we know that current models don't describe dark matter for example, and so they have to be wrong and are likely to be replaced. But the weight of the second hypothesis is on the 'accuracy' of our current models of fundamental physics. As Carroll clearly argues, there is nothing of practical importance in everyday life that we can show to be in violation of the current laws of physics. Of course there will be major breakthroughs in applied physics...major things like figuring out how atoms and cells form brains and intelligence or discovering how to compute solutions of quantum many body systems. But if we are forced to choose between the two hypotheses, I think the evidence leans toward Carroll's side: the fundamental physics of everyday phenomena does not deviate in any significant ways from known physics.
Many people can't seem to see the vast gulf that exists between the discoveries of Maxwell's equations or quantum mechanics (which are necessary to describe matter and light, fundamental aspects of our lives) and current work on dark matter and primordial gravitational waves (which require precision detectors observing things from outside our galaxy). Also, before you dismiss (2) with references to late 19th century quotes about the end of physics, take a few minutes and look at the history beyond the quotes. Those quotes were mined for science funding publicity. Many scientists in the late 19th century knew that they couldn't explain atomic spectra...Kelvin even worked on vortex models of atoms. And if you focus your attention on 'practical' physics, the claims that late 19th century physics was nearly complete turn out not to be too far off...engineers spend almost no time studying quantum mechanics or relativity. It might be 1 or 2 courses out of 20 that cover physics that was discovered since the end of the 19th century. In mechanical engineering there are typically zero courses on quantum mechanics or relativity.
Yes, a more realistic vision of managing science would be an important improvement. Currently you make your way to a permanent position by producing a lot of results that impress established scientists, which in practice often means you extend and confirm their work. This expands the community in which the senior established scientists run the show. But they are expected to manage and do science. Many of them are not skilled in managing, and when they do manage well, they are no longer able to engage in the actual science in a very substantial way. But the managing and doing can't be fully separated. How are management decisions to be made without an awareness of the subtle questions about where barriers to progress will pop up?
If I had one simple way to improve the situation, it would not be to encourage more maverick science. (It is just too difficult to separate true genius mavericks who will make major contributions from the much larger number of delusional smart people who are dreaming up new ways of being totally useless. If there are breakthroughs to be made by genius mavericks, they probably are going to need to make them while serving as patent clerks in the time honored model of Einstein.) I would replace the system of giving credit for large number of papers cited many times. This system reinforces a kind of 'follow the crowd' style of science that creates huge numbers of papers, none of which are particularly clearly written or provides a major advance. More credit needs to be given to people who write fewer clearer papers which waste less of their colleagues valuable time trying to review and decipher. The emphasis should be on the number of significant new ideas contributed and not on the number of highly cited papers which is more a measure of scientific fads than of substance.
No, you already input energy to separate the water and the salt. Remixing them will release part of the energy which could be harnessed, but inevitable losses in conversion will make it better to just use your original energy if you didn't need the fresh water. One nice thing about this article is that they explicitly state the most important point...that it is impractical to use this method in the only context where it would have potential for significant impact which is in the mixing of fresh water rivers with ocean water.
At one level, they are right that unreproducible results are usually not fraud, but are simply fluctuations that make a study look promising leading to publication. But raising the standard of statistical significance will not really improve the situation. The most important uncertainties in most scientific studies are not random. You can't quantify them assuming a gaussian distribution. There are all kind of choices made in acquiring, processing, and presenting data.
The incentives that scientists have are all pushing them to look for ways to obtain a high profile result. We make our best guesses trying to be honest, but when a set of guesses leads to a promising result we publish it and trust further study to determine whether our guesses were fully justified.
There is one step that would improve the situation. We need to provide a mechanism to receive career credit for reproducing earlier results or for disproving earlier results. At the moment, you get no credit for doing this. And you will never get funding to do it. The only way to be successful is to spit out a lot of papers and have some of them turn out to be major results that others build on. The number of papers that turn out to be wrong is of no consequence. No one even notices except a couple of researchers who try to build on your result, fail, and don't publish. In their later papers they will probably carefully dance around the error so as not to incur the wrath of a reviewer. If reproducing earlier results was a priority, then we would know earlier which results were wrong and could start giving negative career credit to people who publish a lot of errors.
Problem is they don't care about quantum computing. What the authors of this proposal mean by 'the national interest' is 'does it enhance the power and prestige of the wealthy interests that currently control much of the US government and economy'. If they had the capability to think about it, they would realize that quantum computing is in their short term interests (it would allow them to read the rest of the global communication that they are not already intercepting), but not in their long term interests (because eventually everyone will switch to quantum information passing for which interception is detectable). But they actually don't know enough to care about quantum computing. They simply want to rule the world and they view scientists as a tool to use toward their ends.
We can be pretty sure that there are new fundamental laws that we don't yet know. The phenomena ascribed to dark matter for example are clearly physical phenomena and there must be fundamental laws that describe them. It is not at all clear that we have exhausted possible means to learn about new fundamental laws. There are improved dark matter searches going on all the time. Gravity wave detectors are likely to find something in the next few decades opening a new window on the universe, and there is a reasonable chance that LHC will show new physics beyond the standard model. It has been slow going compared with the first half of the 20th century, but progress on fundamental laws has not ground to a halt.
You may be hinting that discovery of new fundamental laws may not be very useful for building new technology. There I would probably agree, at least in the next century of two. But that is very different than the claim that we will not discover any new fundamental laws. The deep claim that many people seem not to have accepted yet is the one made by Sean Carroll in his series of blog posts explaining that the physics of everyday life is already understood. 'http://www.preposterousuniverse.com/blog/2010/09/23/the-laws-underlying-the-physics-of-everyday-life-are-completely-understood/'
In his sense, you are right. This is it. We will always be describing our world using concepts of electrons, photons, neutrons, and protons etc. interacting by the four known forces. However, simpler calculating methods may well be possible, like the ones proposed in the original post, which can dramatically change our abilities to predict the outcomes of known fundamental principles.
Yes, you are right. I made a basic mistake. I did 1 m/s^2 rather than 1 g. 350m/s at 1g has a turn radius of 12.2km. Much more manageable. That also gives you 3.7cm misalignment over a 30 m section for 1g which will be much easier to maintain. However, you probably want less than 0.1g rapidly varying acceleration, so alignment at mm or better tolerances may still be required. I think high speed rail are already aligned to mm tolerances without active feedback. It seems like a critical cost question will be whether a good suspension and good static construction methods can maintain adequate alignment or whether they need active feedback. Seems the active feedback would be expensive and difficult.
Yes, evolution has created intelligence without knowing how it works, so it seems it must be possible for us to do it again...although we can't really wait around to develop it by selection on random variations.
It also seems that we easily underestimate the number of kinds of intelligence that may be possible. Although it is possible that human intelligence is a good example of a kind of general intelligence that is evolutionarily convergent and other kinds of intelligence will be similar (although maybe different in degree by being faster or less prone to mistakes (or slower or more prone to mistakes)); it seems more likely to me that human intelligence is one of many ways to understand, and many different kinds of intelligence could be developed depending on which of many different tasks it is being optimized to perform.
So for example, I wouldn't focus on natural language capability if I were working on building AI. And hence I think the Turing test is mostly irrelevant. It seems that language is an unbelievably complicated approximation scheme that humans developed to communicate while avoiding dealing with the complexity of their surroundings. Science developed largely to the degree that we became able to use experiments and mathematics to help us find precision amid the ambiguities involved in human language. I would probably focus on building a system that could simulate its environment, using approximate models to simplify the complex parts to make it computable. Then give the system some kind of way to represent goals and simulate ways to approximately reach those goals. Then try to try the way that seems most promising and learn from mistakes. This is the path that robotics and video games are already going. However the alternate route of trying to understand natural language and use the massive base of human understanding as a starting point for artificial intelligence will continue to be an attractive avenue also.
One of the great open questions about the future of humanity is which will happen first: A) we figure out how our minds are able to understand the world and solve the problems involved in surviving and reproducing. B) we figure out how to build machines that are better than humans at understanding the world and solving the problems involved in surviving and reproducing.
I think it is not at all clear which one will happen first. I think the article's point is exactly right. It doesn't matter what intelligence is. It only matters what intelligence does. The whole field of AI is built around the assumption that we can solve B without solving A. They may be right. Evolution often builds very complicated solutions. Compare a human 'computer' to a calculator doing arithmetic. Clearly we don't need to understand how the brain does this in order to build something better than a human. Maybe the same can be done for general intelligence. Maybe not. I advocate pursuing both avenues.
Since reading the paper on the proposed Hyperloop when it was posted, I have been wondering what piece of the research and development will turn out to be the most difficult. Everyone focuses on the costs and political difficulties of getting this actually built. But at least on/. we should be able to contemplate the engineering without worrying about the biggest problems for these systems which is that foolish humans have to build and use them.:)
It seems to me that maintaining alignment of the tube might be the most difficult challenge. To maintain accelerations below 1g at 350 m/s (782 mph) you have to have a radius of curvature more than 122 km (a=v^2/r). That means the variation from a straight line of only 3.7 mm over the 30 m between pylons will produce 1g. And it takes 0.085 seconds to travel this distance, so it has the potential to produce one hell of a bumpy ride. Now I think they could maintain alignment of a few microns over 30 m and a good suspension could probably remove most of the bumps, but it could be a tough challenge. Since day/night temperature differences and many other things will probably move the pylons on these scales, they are going to need active feedback to maintain alignment.
The alignment will need to be measured and corrected over scales up to at least tens of kilometers. What kind of a system would you use to measure alignment with accuracies of microns over tens of kilometers? What kind of actuators would you use to position a steel tube 2 cm thick and 2.3 m in diameter with accuracy of microns? What failure rate can be tolerated with 25000 pylons? How much would the tube bend if one pylon had its actuators fail or if a semi truck ran into a pylon?
When I first thought of how to build a prototype for this system, I thought of using a circular loop since it would allow a single induction motor to accelerate a cycling capsule many times until it reached full speed, just like a cyclotron. But then I calculated the radius necessary to maintain moderate accelerations, and realized how straight this tube is really going to have to be. Maybe they can use a circular loop to test low speed operation, but even a circle of 10km radius can only go to 70 m/s (158 mph) before going above 1g. In a 1km radius circular loop at 350 m/s you have 122g. So the high speed tests are going to have to be in a straight test facility with linear motors capable of taking the capsule up to full speed.
That is a very interesting result. Their first measurements of the positron energy spectrum are consistent with super-symmetry ideas about dark matter collisions creating positron-electron pairs. If it turns out to be right, it will be the first non-gravitational detection of dark matter. But there is not much experimental support for the super-symmetry ideas being used to connect dark matter with positrons, and there are other possible sources of the positron spectrum at the current accuracy. So we'll see. It is great to see they have some results...this experiment has taken a long time and a lot of money. But when you introduce a much more precise way to measure, it usually turns out to be worth the cost and effort in the end.
Economist tech news seems to always have these breathless descriptions of new technologies that will change everything without bothering to understand the underlying science. Why let facts get in the way of a story that sells? At the root of it, I think some economists realize that the model of continuous exponential growth used in their models depends on continuous revolutionary break-throughs in energy technology and basic materials. Since the recent reality has only had incremental changes, they feel pressed to make up revolutions in hope that it will save their models.
I think you misunderstand the situation with our understanding of gravity. We already have a theory that describes everything we have been able to observe on scales smaller than a galaxy. This is very different than magnetism where we were using magnets for hundreds of years before we had an adequate theory. My point is that solving a theoretical inconsistency (like quantum gravity) has no clear practical consequences when there are no observations that need to be explained.
Nuclear reactions are already well within the range of energy scales that are fully described by our current theories. You have to be at truly exotic energies that haven't existed since the big bang (except in very rare cosmic rays or in our future particle colliders) before you might find deviations from our current theories.
Many of you seem focused on Star Trek. Does it not seem a little odd that it is fictional entertainment rather than experiments that are being used to decide what is physically possible? No one has ever detected anything moving faster than the speed of light. A hint of neutrinos going 1 part in a million faster than light was treated as a major anomaly this past year, until it was found to be an experimental error. There is no reason whatsoever to expect warp drives...except the human attraction to wishful thinking. And there is also no reason to think that wormholes exist or that we would be able to manipulate them.
There are many cases like this. I mentioned the human brain. But there is no evidence to suggest that superconductivity is not simply many body quantum mechanics. Unsolvable at the moment, yes. But it doesn't show any deviations from current theory in a fundamental sense.
The only way to manipulate gravity that anyone has found is to move mass around. Similarly, we manipulate electromagnetism by moving charges around. But we don't have a theory of quantum gravity precisely because we have not found any ways of moving masses that doesn't agree with the predictions of general relativity. In short, there is no evidence of any effects of quantum gravity that could be exploited for any of the Star Trek like manipulations of gravity. For E&M, the situation was exactly the opposite. There were a hole bunch of observed phenomena before there was any useful theory.
The last two examples (superconductivity and biology) fall into the latter part of my comment...There will be major revolutions. But they will not be in fundamental physics. They will be in our ability to use our known theories to predict the behavior of complex systems.
You are after increases in our experimental capabilities, but mbkennel is talking about something else. The materials and processes relevant to our lives on earth are largely understood at a fundamental level. That is a major difference that isn't going to be changed by more precise experiments. Say we can measure collisions at 500 TeV rather than 8 TeV currently. It may produce a breakthrough in particle physics. But what materials and processes relevant to our lives will be revolutionized? (Now of course we can't predict the behavior of many things relevant to our lives, and there are major breakthroughs available there, but it won't be in fundamental physics).
Your list is a bit problematic. We have excellent theories of quantum electrodynamics that are compatible with special relativity and effectively answer 1,2 7 and 9. 3 is good: there would be a nobel prize for anyone who creates a successful theory of quantum gravity. 4 is like asking 'does bigfoot exist'. We have very good reasons to think the answer is no. 5 wouldn't get you a nobel prize becomes the first publication was last summer. 6 has a definite answer 'yes and no: top quarks decay, electrons do not'. I suppose you mean 'do protons decay'. That one would get you a nobel prize. 8 would also get you a nobel prize, but you would have to connect it to something measurable, which the string theorists seem to strictly avoid. And 11 and 12 are good questions for the sociologists and philosophers. 10 amounts to about the same thing as 3, basically it is asking for quantum general relativity. But none of these questions (excepting the last two non-scientific ones) have any clear practical relevance to our world. What technology will you build after answering them?
mbkennel is right. Before the quantum revolution there were a few people who declared that they understood almost everything (Michelson's quote is famous), but the wiser ones clearly knew that they could not explain many properties of matter including discrete spectra, heat capacities, and most of chemistry. Check a biography of Lord Kelvin to note how early these problems were clearly appreciated. The three mysteries s/he cites are a good summary. Note how huge the difference is between today and the 19th century. The first two mysteries have no currently observable effects on scales much smaller than a galaxy. And the third is a 'we don't know why the universe has a specific set of parameters' question. Answering it will be extremely interesting, but there are not a bunch of practically important unexplained phenomena waiting to be united with our deeper understanding if it arrives.
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Your last comment is about political control. You seem to mean that our phenomenology will improve as big data mines human behavior and we learn to use that data and those ideas to control others. We do need to be careful who controls that. Although I suspect that the degree of control achievable by such means is easy to overestimate.
This hope for an effective theory of human behavior is a reasonable hope. There might be a simple effective model that could describe human behavior without accounting for all of the parameters needed to fully specify the problem. It happens in many fields. We can very accurately predict fluid flows without worrying about the parameters of all the molecules. But for humans, it really is hard to imaging how it might work out. Consider the fact that once some humans have a theory of how humans behave, someone will start using it to gain a competitive advantage and then other people will start changing their behavior in response to knowledge that the theory is being used. It is a fascinating way to be unknowable...to be guaranteed to change as soon as anyone figures it out.
Many of us technical types would love for this line of inquiry to be fruitful. But to have a 'physics of people' you have to know the values of all the parameters needed to specify the current state of a person and you need to know all interactions of that person with the rest of the universe. Phrased like that you can see how ludicrous it is to dream of using the methods of physics for social science. Physics works because the fundamental constituents of the universe happen to be only a small number of particles whose interactions are amazingly simple. For example all electrons are exactly identical and interact via only 3 forces (with some uncertainties about effects on scales larger than galaxies and energies higher than trillions of electron volts). The hope for a theory of sociology is a false hope. The hope for a useful phenomenology might be more reasonable and big data can help.
With inflation and continued erosion of social security and other retirement income sources other than assets, my calculations say that I simply can't retire with a middle class income if I don't have quite a bit more than $1 million in 2040 when I retire. Real returns are below 5% these days, and $1million kicks off less than $50,000 per year which will likely be well below median in 2040. As others have noted, it is not all that hard to reach $1 million with regular investing and modest real returns (and assuming we don't have a market collapse which is not an entirely justified assumption). But it is a system that a large number of numerically handicapped Americans seem not to be able to plan for or cope with. I would translate the headline: "44% of US developers don't think they are going to be able to retire (or simply have never done the math)".
Not sure what you mean there. Quantum mechanics is hugely important for everyday life--all the biochemistry of life is quantum mechanics. So the ability to build a quantum computer would be expected to open up vast new possibilities. But that will function on the basis of known physics. My comments about the limited engineering uses of quantum mechanics so far was meant to point out how it is easy to overestimate the practical use of fundamental theories even when the theories describe all the matter around us. The question at hand is whether unknown physics (dark matter, undiscovered particles, etc) affects everyday life or will have a practical impact on technology. If it does, it will probably be in applications that involve precision measurement where you need 15 digits of accuracy so that Feynman diagrams including particles beyond the standard model become important.
It might have been better if I had phrased (2) a little more strongly like Carroll did: something like 'the physics of everyday life is completely understood' or 'there will be no practical applications of physics beyond our current theories (the standard model and general relativity)'.
Yes they might be compatible. But if (2) is true, then the discoveries of (1) quickly become irrelevant. This is what Horgan is getting at. If new theoretical ideas don't have any practical implications for our corner of the milky way galaxy, it is going to become very very hard to keep up a never ending sequence of experimentally confirmed discoveries.
Note that Carroll was not claiming that Newtonian mechanics explained all of everyday life. He was claiming that the standard model plus general relativity contained all of everyday life. The analogy to Newtonian mechanics is to help people see how little impact on everyday engineering practice even the discovery of quantum mechanics had (and QM is a hugely practical theory that explains materials, semi-conductors, etc as you note). My guess is that the quantitative discrepancies between current predictions and measurements leave little hope that discoveries beyond the standard model and GR are going to have any practical applications except maybe in the distant future if we need 15 digits in the magnetic dipole moment of the muon or are trying to travel outside our galaxy or are considering the heat death of the universe. Like Horgan, I would love to be wrong. But I just haven't heard any good empirical arguments to support claim (1) that are deeper than 'past performance predicts future results' mixed up with wishful thinking.
The mercury/Vulcan reference is an interesting one. Note that the precession of Mercury is a pretty small effect and the GR effects that produce it have only recently begun to have practical applications in the global positioning system clocks. Do you have modern candidates to propose where unobserved entities are hypothesized to patch up measurements with the standard model or GR? Dark matter and Dark energy are the obvious candidates. The Higgs particle also could have been such a thing. If it had not been observed we might have needed a paradigm shift, but even that probably would not have made much practical difference. You don't need to be able to predict the masses of the particles in the standard model for practical purposes. It works quite well to measure their properties and use that to predict how they behave.
A 19th century analogy is to chemistry. Chemists in the late 19th century were able to put in place much of modern chemistry without having correct ideas about how a chemical bond actually worked. Quantum physics did not replace chemistry. It mostly explained things that were already known. But it did something else...it suggested where to look for new discoveries: the addition of Hafnium to the periodic table for example. It also opened up precision calculations of bond energies, bond lengths, etc which have been quite useful. That is what happened when we finally figured out how ordinary matter works...the stuff we are made of. (1) is a guess that figuring out what dark matter is or the properties of possible non standard model particles formed at energies above 100GeV will guide us to new areas of inquiry that lead to breakthroughs and practical applications. But it seems an unsupported guess. We already have discoveries like the top quarks and tau neutrino that didn't lead to any significant breakthroughs or new technology. Does anyone have any dark matter hypotheses for which they have a potential application? It is just very hard to imagine what one could do with a source of gravitational force that interacts so weakly with ordinary matter than it is currently only detectable on length scales of an entire galaxy. And dark energy is much much farther from engineering use.
So let's keep trying to find new breakthroughs. But it is also good to be honest with ourselves about what we have reasons to expect and what is wishful thinking.
The subject of the likelihood of future breakthroughs in basic science is very important. But Horgan is not very good at articulating the main issues. Much better is Sean Carroll's blog: http://www.preposterousunivers...
To simplify the situation to make it comprehensible, consider two hypotheses about the future of science. (1) Science will have an eternal sequence of groundbreaking discoveries/paradigm shifts. (2) The highly successful models we currently use are so accurate that they will continue to be used forever.
The first hypothesis is beloved by scientists in search of funding and by sociologists of science who wish to treat science as merely a social construct. It really is a strange alliance, but a common cause can make strange bedfellows. The second hypothesis is much less widely defended. Partly because it is clearly false in a fundamental sense...we know that current models don't describe dark matter for example, and so they have to be wrong and are likely to be replaced. But the weight of the second hypothesis is on the 'accuracy' of our current models of fundamental physics. As Carroll clearly argues, there is nothing of practical importance in everyday life that we can show to be in violation of the current laws of physics. Of course there will be major breakthroughs in applied physics...major things like figuring out how atoms and cells form brains and intelligence or discovering how to compute solutions of quantum many body systems. But if we are forced to choose between the two hypotheses, I think the evidence leans toward Carroll's side: the fundamental physics of everyday phenomena does not deviate in any significant ways from known physics.
Many people can't seem to see the vast gulf that exists between the discoveries of Maxwell's equations or quantum mechanics (which are necessary to describe matter and light, fundamental aspects of our lives) and current work on dark matter and primordial gravitational waves (which require precision detectors observing things from outside our galaxy). Also, before you dismiss (2) with references to late 19th century quotes about the end of physics, take a few minutes and look at the history beyond the quotes. Those quotes were mined for science funding publicity. Many scientists in the late 19th century knew that they couldn't explain atomic spectra...Kelvin even worked on vortex models of atoms. And if you focus your attention on 'practical' physics, the claims that late 19th century physics was nearly complete turn out not to be too far off...engineers spend almost no time studying quantum mechanics or relativity. It might be 1 or 2 courses out of 20 that cover physics that was discovered since the end of the 19th century. In mechanical engineering there are typically zero courses on quantum mechanics or relativity.
Yes, a more realistic vision of managing science would be an important improvement. Currently you make your way to a permanent position by producing a lot of results that impress established scientists, which in practice often means you extend and confirm their work. This expands the community in which the senior established scientists run the show. But they are expected to manage and do science. Many of them are not skilled in managing, and when they do manage well, they are no longer able to engage in the actual science in a very substantial way. But the managing and doing can't be fully separated. How are management decisions to be made without an awareness of the subtle questions about where barriers to progress will pop up?
If I had one simple way to improve the situation, it would not be to encourage more maverick science. (It is just too difficult to separate true genius mavericks who will make major contributions from the much larger number of delusional smart people who are dreaming up new ways of being totally useless. If there are breakthroughs to be made by genius mavericks, they probably are going to need to make them while serving as patent clerks in the time honored model of Einstein.) I would replace the system of giving credit for large number of papers cited many times. This system reinforces a kind of 'follow the crowd' style of science that creates huge numbers of papers, none of which are particularly clearly written or provides a major advance. More credit needs to be given to people who write fewer clearer papers which waste less of their colleagues valuable time trying to review and decipher. The emphasis should be on the number of significant new ideas contributed and not on the number of highly cited papers which is more a measure of scientific fads than of substance.
No, you already input energy to separate the water and the salt. Remixing them will release part of the energy which could be harnessed, but inevitable losses in conversion will make it better to just use your original energy if you didn't need the fresh water. One nice thing about this article is that they explicitly state the most important point...that it is impractical to use this method in the only context where it would have potential for significant impact which is in the mixing of fresh water rivers with ocean water.
At one level, they are right that unreproducible results are usually not fraud, but are simply fluctuations that make a study look promising leading to publication. But raising the standard of statistical significance will not really improve the situation. The most important uncertainties in most scientific studies are not random. You can't quantify them assuming a gaussian distribution. There are all kind of choices made in acquiring, processing, and presenting data. The incentives that scientists have are all pushing them to look for ways to obtain a high profile result. We make our best guesses trying to be honest, but when a set of guesses leads to a promising result we publish it and trust further study to determine whether our guesses were fully justified. There is one step that would improve the situation. We need to provide a mechanism to receive career credit for reproducing earlier results or for disproving earlier results. At the moment, you get no credit for doing this. And you will never get funding to do it. The only way to be successful is to spit out a lot of papers and have some of them turn out to be major results that others build on. The number of papers that turn out to be wrong is of no consequence. No one even notices except a couple of researchers who try to build on your result, fail, and don't publish. In their later papers they will probably carefully dance around the error so as not to incur the wrath of a reviewer. If reproducing earlier results was a priority, then we would know earlier which results were wrong and could start giving negative career credit to people who publish a lot of errors.
Problem is they don't care about quantum computing. What the authors of this proposal mean by 'the national interest' is 'does it enhance the power and prestige of the wealthy interests that currently control much of the US government and economy'. If they had the capability to think about it, they would realize that quantum computing is in their short term interests (it would allow them to read the rest of the global communication that they are not already intercepting), but not in their long term interests (because eventually everyone will switch to quantum information passing for which interception is detectable). But they actually don't know enough to care about quantum computing. They simply want to rule the world and they view scientists as a tool to use toward their ends.
We can be pretty sure that there are new fundamental laws that we don't yet know. The phenomena ascribed to dark matter for example are clearly physical phenomena and there must be fundamental laws that describe them. It is not at all clear that we have exhausted possible means to learn about new fundamental laws. There are improved dark matter searches going on all the time. Gravity wave detectors are likely to find something in the next few decades opening a new window on the universe, and there is a reasonable chance that LHC will show new physics beyond the standard model. It has been slow going compared with the first half of the 20th century, but progress on fundamental laws has not ground to a halt.
You may be hinting that discovery of new fundamental laws may not be very useful for building new technology. There I would probably agree, at least in the next century of two. But that is very different than the claim that we will not discover any new fundamental laws. The deep claim that many people seem not to have accepted yet is the one made by Sean Carroll in his series of blog posts explaining that the physics of everyday life is already understood. 'http://www.preposterousuniverse.com/blog/2010/09/23/the-laws-underlying-the-physics-of-everyday-life-are-completely-understood/' In his sense, you are right. This is it. We will always be describing our world using concepts of electrons, photons, neutrons, and protons etc. interacting by the four known forces. However, simpler calculating methods may well be possible, like the ones proposed in the original post, which can dramatically change our abilities to predict the outcomes of known fundamental principles.
This comment sounds like Elon Musk himself. There is even a Freudian slip 'we'. http://www.popularmechanics.com/how-to/blog/elon-musk-on-spacex-tesla-and-why-space-solar-power-must-die-13386162
Yes, you are right. I made a basic mistake. I did 1 m/s^2 rather than 1 g. 350m/s at 1g has a turn radius of 12.2km. Much more manageable. That also gives you 3.7cm misalignment over a 30 m section for 1g which will be much easier to maintain. However, you probably want less than 0.1g rapidly varying acceleration, so alignment at mm or better tolerances may still be required. I think high speed rail are already aligned to mm tolerances without active feedback. It seems like a critical cost question will be whether a good suspension and good static construction methods can maintain adequate alignment or whether they need active feedback. Seems the active feedback would be expensive and difficult.
Yes, evolution has created intelligence without knowing how it works, so it seems it must be possible for us to do it again...although we can't really wait around to develop it by selection on random variations.
It also seems that we easily underestimate the number of kinds of intelligence that may be possible. Although it is possible that human intelligence is a good example of a kind of general intelligence that is evolutionarily convergent and other kinds of intelligence will be similar (although maybe different in degree by being faster or less prone to mistakes (or slower or more prone to mistakes)); it seems more likely to me that human intelligence is one of many ways to understand, and many different kinds of intelligence could be developed depending on which of many different tasks it is being optimized to perform.
So for example, I wouldn't focus on natural language capability if I were working on building AI. And hence I think the Turing test is mostly irrelevant. It seems that language is an unbelievably complicated approximation scheme that humans developed to communicate while avoiding dealing with the complexity of their surroundings. Science developed largely to the degree that we became able to use experiments and mathematics to help us find precision amid the ambiguities involved in human language. I would probably focus on building a system that could simulate its environment, using approximate models to simplify the complex parts to make it computable. Then give the system some kind of way to represent goals and simulate ways to approximately reach those goals. Then try to try the way that seems most promising and learn from mistakes. This is the path that robotics and video games are already going. However the alternate route of trying to understand natural language and use the massive base of human understanding as a starting point for artificial intelligence will continue to be an attractive avenue also.
One of the great open questions about the future of humanity is which will happen first: A) we figure out how our minds are able to understand the world and solve the problems involved in surviving and reproducing. B) we figure out how to build machines that are better than humans at understanding the world and solving the problems involved in surviving and reproducing.
I think it is not at all clear which one will happen first. I think the article's point is exactly right. It doesn't matter what intelligence is. It only matters what intelligence does. The whole field of AI is built around the assumption that we can solve B without solving A. They may be right. Evolution often builds very complicated solutions. Compare a human 'computer' to a calculator doing arithmetic. Clearly we don't need to understand how the brain does this in order to build something better than a human. Maybe the same can be done for general intelligence. Maybe not. I advocate pursuing both avenues.
Since reading the paper on the proposed Hyperloop when it was posted, I have been wondering what piece of the research and development will turn out to be the most difficult. Everyone focuses on the costs and political difficulties of getting this actually built. But at least on /. we should be able to contemplate the engineering without worrying about the biggest problems for these systems which is that foolish humans have to build and use them. :)
It seems to me that maintaining alignment of the tube might be the most difficult challenge. To maintain accelerations below 1g at 350 m/s (782 mph) you have to have a radius of curvature more than 122 km (a=v^2/r). That means the variation from a straight line of only 3.7 mm over the 30 m between pylons will produce 1g. And it takes 0.085 seconds to travel this distance, so it has the potential to produce one hell of a bumpy ride. Now I think they could maintain alignment of a few microns over 30 m and a good suspension could probably remove most of the bumps, but it could be a tough challenge. Since day/night temperature differences and many other things will probably move the pylons on these scales, they are going to need active feedback to maintain alignment.
The alignment will need to be measured and corrected over scales up to at least tens of kilometers. What kind of a system would you use to measure alignment with accuracies of microns over tens of kilometers? What kind of actuators would you use to position a steel tube 2 cm thick and 2.3 m in diameter with accuracy of microns? What failure rate can be tolerated with 25000 pylons? How much would the tube bend if one pylon had its actuators fail or if a semi truck ran into a pylon?
When I first thought of how to build a prototype for this system, I thought of using a circular loop since it would allow a single induction motor to accelerate a cycling capsule many times until it reached full speed, just like a cyclotron. But then I calculated the radius necessary to maintain moderate accelerations, and realized how straight this tube is really going to have to be. Maybe they can use a circular loop to test low speed operation, but even a circle of 10km radius can only go to 70 m/s (158 mph) before going above 1g. In a 1km radius circular loop at 350 m/s you have 122g. So the high speed tests are going to have to be in a straight test facility with linear motors capable of taking the capsule up to full speed.
That is a very interesting result. Their first measurements of the positron energy spectrum are consistent with super-symmetry ideas about dark matter collisions creating positron-electron pairs. If it turns out to be right, it will be the first non-gravitational detection of dark matter. But there is not much experimental support for the super-symmetry ideas being used to connect dark matter with positrons, and there are other possible sources of the positron spectrum at the current accuracy. So we'll see. It is great to see they have some results...this experiment has taken a long time and a lot of money. But when you introduce a much more precise way to measure, it usually turns out to be worth the cost and effort in the end.
Economist tech news seems to always have these breathless descriptions of new technologies that will change everything without bothering to understand the underlying science. Why let facts get in the way of a story that sells? At the root of it, I think some economists realize that the model of continuous exponential growth used in their models depends on continuous revolutionary break-throughs in energy technology and basic materials. Since the recent reality has only had incremental changes, they feel pressed to make up revolutions in hope that it will save their models.
I think you misunderstand the situation with our understanding of gravity. We already have a theory that describes everything we have been able to observe on scales smaller than a galaxy. This is very different than magnetism where we were using magnets for hundreds of years before we had an adequate theory. My point is that solving a theoretical inconsistency (like quantum gravity) has no clear practical consequences when there are no observations that need to be explained.
Nuclear reactions are already well within the range of energy scales that are fully described by our current theories. You have to be at truly exotic energies that haven't existed since the big bang (except in very rare cosmic rays or in our future particle colliders) before you might find deviations from our current theories.
Many of you seem focused on Star Trek. Does it not seem a little odd that it is fictional entertainment rather than experiments that are being used to decide what is physically possible? No one has ever detected anything moving faster than the speed of light. A hint of neutrinos going 1 part in a million faster than light was treated as a major anomaly this past year, until it was found to be an experimental error. There is no reason whatsoever to expect warp drives...except the human attraction to wishful thinking. And there is also no reason to think that wormholes exist or that we would be able to manipulate them.
There are many cases like this. I mentioned the human brain. But there is no evidence to suggest that superconductivity is not simply many body quantum mechanics. Unsolvable at the moment, yes. But it doesn't show any deviations from current theory in a fundamental sense.
The only way to manipulate gravity that anyone has found is to move mass around. Similarly, we manipulate electromagnetism by moving charges around. But we don't have a theory of quantum gravity precisely because we have not found any ways of moving masses that doesn't agree with the predictions of general relativity. In short, there is no evidence of any effects of quantum gravity that could be exploited for any of the Star Trek like manipulations of gravity. For E&M, the situation was exactly the opposite. There were a hole bunch of observed phenomena before there was any useful theory. The last two examples (superconductivity and biology) fall into the latter part of my comment...There will be major revolutions. But they will not be in fundamental physics. They will be in our ability to use our known theories to predict the behavior of complex systems.
You are after increases in our experimental capabilities, but mbkennel is talking about something else. The materials and processes relevant to our lives on earth are largely understood at a fundamental level. That is a major difference that isn't going to be changed by more precise experiments. Say we can measure collisions at 500 TeV rather than 8 TeV currently. It may produce a breakthrough in particle physics. But what materials and processes relevant to our lives will be revolutionized? (Now of course we can't predict the behavior of many things relevant to our lives, and there are major breakthroughs available there, but it won't be in fundamental physics).
Your list is a bit problematic. We have excellent theories of quantum electrodynamics that are compatible with special relativity and effectively answer 1,2 7 and 9. 3 is good: there would be a nobel prize for anyone who creates a successful theory of quantum gravity. 4 is like asking 'does bigfoot exist'. We have very good reasons to think the answer is no. 5 wouldn't get you a nobel prize becomes the first publication was last summer. 6 has a definite answer 'yes and no: top quarks decay, electrons do not'. I suppose you mean 'do protons decay'. That one would get you a nobel prize. 8 would also get you a nobel prize, but you would have to connect it to something measurable, which the string theorists seem to strictly avoid. And 11 and 12 are good questions for the sociologists and philosophers. 10 amounts to about the same thing as 3, basically it is asking for quantum general relativity. But none of these questions (excepting the last two non-scientific ones) have any clear practical relevance to our world. What technology will you build after answering them?
mbkennel is right. Before the quantum revolution there were a few people who declared that they understood almost everything (Michelson's quote is famous), but the wiser ones clearly knew that they could not explain many properties of matter including discrete spectra, heat capacities, and most of chemistry. Check a biography of Lord Kelvin to note how early these problems were clearly appreciated. The three mysteries s/he cites are a good summary. Note how huge the difference is between today and the 19th century. The first two mysteries have no currently observable effects on scales much smaller than a galaxy. And the third is a 'we don't know why the universe has a specific set of parameters' question. Answering it will be extremely interesting, but there are not a bunch of practically important unexplained phenomena waiting to be united with our deeper understanding if it arrives.