Your examples are all very good, but I would take issue with your comparisons to the ridiculous cost of a Space Shuttle launch. SpaceX's budget would be orders of magnitude larger as well if they had to launch a payload that big with people on board.
that exists mainly as welfare for mediocre engineers?
Would you care to elaborate on or support this point? I find it is needlessly inflammatory and just downright rude. By what metric of engineering excellence are you using? Where are all the excellent rocket engineers working? Are the only good rocket engineers in the US working for SpaceX? Because the two 800 lb gorillas in the industry have a lock on the rocket launch business, one could argue that it is they who have the wherewithal to hire the best engineers.
What sort of campuses are you talking about? On all the campuses, large and small, that I have been on, this is not the case. It would put a big damper on attracting people to lectures, cultural events, plays, etc. that the colleges and universities actively promote outside the campus. Are you over-generalizing from some isolated event ("Don't taze me bro")? Now maybe if you are talking about hanging out in the bushes outside the women's dorm, then yeah, that will probably happen to you.
This is addressed in the paper. The paper abstract:
Material from the surface of a planet can be ejected into space by a large
impact, and could carry primitive life forms with it. We performed n-body
simulations of such ejecta to determine where in the Solar System rock from
Earth and Mars may end up. We find that, in addition to frequent transfer of
material among the terrestrial planets, transfer of material from Earth and
Mars to the moons of Jupiter and Saturn is also possible, but rare. We expect
that such transfer is most likely during the Late Heavy Bombardment or
during the next one or two billion years. At this time, the icy moons were
warmer and likely had little or no icy shell to prevent meteorites from reaching
their liquid interiors. We also note significant rates of re-impact in the first
million years after ejection. This could re-seed life on a planet after partial or
complete sterilization by a large impact, which would aid the survival of early
life during the Late Heavy Bombardment.
Panspermia is the hypothesis that life can be spread between planets and
planetary systems. One class of panspermia is lithopanspermia, in which
pieces of rock are the mechanism for dispersal (Tobias & Todd, 1974; Melosh,
1988). Rock fragments can be ejected from an inhabited planet's surface via
large meteor impact. This ejected material can then travel through space and
may land on another planet or moon, as we have seen in identified meteorites
from Mars found on Earth (Bogard & Johnson, 1983; Carr et al., 1985). If an
ejected rock encases sufficiently resilient organisms, life could be seeded on
its destination planet or moon.
Your point is well taken. Why do so many people here talk about the accuracy of bombs? You'd think that on this site with so many supposedly tech-savvy people that they would figure out that there are a few other interesting uses for an accurate GPS system than cruise missiles.
Excellent point. Another thing I find interesting whenever I see press about her, it is usually "MIT engineer." I'm not sure why MIT is always thrown in there. I guess it has more cachet than "Purdue University engineer" or "University of Illinois at Urbana-Champaign engineer" or just plain old engineer, but I find it largely irrelevant nonetheless.
The large scale beer producers operate for the most part on a very slim profit margin. Unless this is somehow cheaper to produce than mashing malted barley, they wouldn't care about it one way or the other. Alcohol is a large part of the taste of beer and other alcoholic beverages (taste a non-alcoholic beer, or a Malta Goya) so you'd need to figure out how to replace ethanol and not change the taste. I doubt the big beer producers give a rat's ass about this at all; if they see any worth in it, they'd work with him. That industry is not afraid of change; witness the failed attempts at clear beer, Zima and its ilk, all the current alco-pops. If they see a potential opening into a new market segment, they go after it aggressively until it doesn't pan out.
However, it certainly sounds much better, in a pull for the underdog way, to say "and it would have worked if it wasn't for those meddling beer companies and that dog".
What you are looking at in the picture is the waveguide they used to test it. The antenna itself is inside the waveguide and is a split ring resonator, 40 mm on a side.
Actually, the difference here is that they built a rectenna out of metamaterials, specifically a split-ring resonator (SRR) design. I presume their point here is that they came up with a compact rectenna design that can work fairly well at 900 MHz. The paper you referenced with the 82% efficiency used a dipole antenna for 5.8 GHz. The wavelength at 5.8 GHz is something like 50 mm, and they used a 1/2 wave dipole antenna (their length was around 25 mm). The wavelength at 900 MHz is 333 mm, but their SRR design was only 40 mm on a side (a 1/2 wave dipole would have to be 150 mm or so).
I don't think they were making any claims of new physics here, but probably pointing out a design that would be fairly compact and leverage all the 900 MHz EMI flying around. For what its worth, their max efficiency occurred for a resistive load of 70 Ohms, which is a reasonable load for something that you want to power with an energy harvester.
I suppose I may click through to see what the actual ad said, because the person above suggested that it was at least indirectly addressing the Snowden situation, but for years I've seen them heavily active in recruitment and even small business outreach. If you go to a technical conference expo, it wouldn't be a surprise to see them have a booth, or the CIA, or FBI, or whatever. I think most people don't realize how big of a place the NSA is. Like all other large institutions (National Institutes of Health, any of the National Labs, all universities) they have divisions that specialize in work on this or that, so this group over there might be involved in the data surveillance thing, but these groups over there are doing completely different things. Any ad from them to recruit you to come work for them is going to say you'll do real cool work, and it will have an appeal to a sense of God and country. How else are you supposed to do the sell?
The NSA advertises jobs all the time in a variety of formats. They have recruitment booths at technical conferences, internships, etc.. They have a whole web site and all. What is particularly newsworthy about this?
There are some really interesting experiments going on these days with QM behavior of macroscopic objects (micrometer-scale). I've seen descriptions of MEMS cantilevers built and they measure its vibrational modes, and these guys describe how they did it using reflected laser light. The trick is to cool the device to get rid of the phonons and detect when it falls into the ground state.
The 20-year frequency estimate uses and extends the infrasound-based estimates. From the Brown et. al. paper:
Using our best estimate for the Chelyabinsk airburst energy, of about 500 kt, we have estimated the bolide flux at the Earth over the
period from 1994 to mid-2013. This estimate is based on 20 years of
total global coverage by the US government or infrasound sensors,
more than doubling the earlier time coverage.
The beauty, of course, is because it was so precisely ground into a wonderfully specific shape (it gave perfect spherical aberration), it was easy to make corrective lenses.
From what I know of everyday life in the US from friends and Slashdot posters . ..
You would have a very myopic view of the US in particular, and the world in general, if you are basing it off of Slashdot posters. Indeed, I can form a very clear opinion of Europeans from Slashdot posters as well, but I don't think you would find it reflects your experience.
I always found the browser search hijack to be rather annoying. That, and the majority of my fortune quotes suddenly were from someone named Husse, who nice guy and all as he seemed to be, the quotes meant nothing to me since I never interacted with him on the Mint forum.
if we don't actually need this helium reserve lying around forever, selling it off slowly seems like a reasonable thing to do.
One of the many problems with the Helium Privatization Act of 1996 is that it mandated that the sell-off was to be linear, not based upon supply, demand, or any other aspect of the marketplace. So every year the Bureau of Land Management had to sell of X many units.
The Government wasn't selling it below market cost to encourage scientific applications or for any other reason based upon intelligence, foresight, or reality. It is because Congress passed a law forcing the helium reserve to be sold off (Helium Privatization Act of 1996). The pricing mechanism worked into the law bears no relationship to the market price of helium. It was as much a horrible idea at the time as it is now. Too bad it only took almost 20 years to address.
Plus, if Spiegelman was fairly well known for this kind of research, the journal editors should have asked him or one of his colleagues to be one of the reviewers.
If it is true that they have a terrible peer review process, then I think it is very relevant to the story. They must have a terrible peer review process if the paper got published. Normally there would be several rounds of give and take between the paper authors and the journal editors and reviewers, which either wasn't done, or was done through some manner of communication such as using personal email accounts.
Better yet, they could build a big arena and everyone who goes to the arena could float up in the air before they vaporize. At birth we could implant a crystal in everyone's hand, and when their crystal starts flashing, that's when they know to go to the arena. The criteria for when their crystal flashes, we can figure that out later. Base it on their age or something....
Slashdot Mirror
Your examples are all very good, but I would take issue with your comparisons to the ridiculous cost of a Space Shuttle launch. SpaceX's budget would be orders of magnitude larger as well if they had to launch a payload that big with people on board.
that exists mainly as welfare for mediocre engineers?
Would you care to elaborate on or support this point? I find it is needlessly inflammatory and just downright rude. By what metric of engineering excellence are you using? Where are all the excellent rocket engineers working? Are the only good rocket engineers in the US working for SpaceX? Because the two 800 lb gorillas in the industry have a lock on the rocket launch business, one could argue that it is they who have the wherewithal to hire the best engineers.
What sort of campuses are you talking about? On all the campuses, large and small, that I have been on, this is not the case. It would put a big damper on attracting people to lectures, cultural events, plays, etc. that the colleges and universities actively promote outside the campus. Are you over-generalizing from some isolated event ("Don't taze me bro")? Now maybe if you are talking about hanging out in the bushes outside the women's dorm, then yeah, that will probably happen to you.
This is addressed in the paper. The paper abstract:
Material from the surface of a planet can be ejected into space by a large impact, and could carry primitive life forms with it. We performed n-body simulations of such ejecta to determine where in the Solar System rock from Earth and Mars may end up. We find that, in addition to frequent transfer of material among the terrestrial planets, transfer of material from Earth and Mars to the moons of Jupiter and Saturn is also possible, but rare. We expect that such transfer is most likely during the Late Heavy Bombardment or during the next one or two billion years. At this time, the icy moons were warmer and likely had little or no icy shell to prevent meteorites from reaching their liquid interiors. We also note significant rates of re-impact in the first million years after ejection. This could re-seed life on a planet after partial or complete sterilization by a large impact, which would aid the survival of early life during the Late Heavy Bombardment.
From the first paragraph in their paper:
Panspermia is the hypothesis that life can be spread between planets and planetary systems. One class of panspermia is lithopanspermia, in which pieces of rock are the mechanism for dispersal (Tobias & Todd, 1974; Melosh, 1988). Rock fragments can be ejected from an inhabited planet's surface via large meteor impact. This ejected material can then travel through space and may land on another planet or moon, as we have seen in identified meteorites from Mars found on Earth (Bogard & Johnson, 1983; Carr et al., 1985). If an ejected rock encases sufficiently resilient organisms, life could be seeded on its destination planet or moon.
Imagining that all life must have originated from Earth is an amazingly earth-centric point of view
This claim is not made anywhere in the paper, or anywhere else for that matter that I can find.
Your point is well taken. Why do so many people here talk about the accuracy of bombs? You'd think that on this site with so many supposedly tech-savvy people that they would figure out that there are a few other interesting uses for an accurate GPS system than cruise missiles.
Excellent point. Another thing I find interesting whenever I see press about her, it is usually "MIT engineer." I'm not sure why MIT is always thrown in there. I guess it has more cachet than "Purdue University engineer" or "University of Illinois at Urbana-Champaign engineer" or just plain old engineer, but I find it largely irrelevant nonetheless.
The large scale beer producers operate for the most part on a very slim profit margin. Unless this is somehow cheaper to produce than mashing malted barley, they wouldn't care about it one way or the other. Alcohol is a large part of the taste of beer and other alcoholic beverages (taste a non-alcoholic beer, or a Malta Goya) so you'd need to figure out how to replace ethanol and not change the taste. I doubt the big beer producers give a rat's ass about this at all; if they see any worth in it, they'd work with him. That industry is not afraid of change; witness the failed attempts at clear beer, Zima and its ilk, all the current alco-pops. If they see a potential opening into a new market segment, they go after it aggressively until it doesn't pan out.
However, it certainly sounds much better, in a pull for the underdog way, to say "and it would have worked if it wasn't for those meddling beer companies and that dog".
What you are looking at in the picture is the waveguide they used to test it. The antenna itself is inside the waveguide and is a split ring resonator, 40 mm on a side.
Actually, the difference here is that they built a rectenna out of metamaterials, specifically a split-ring resonator (SRR) design. I presume their point here is that they came up with a compact rectenna design that can work fairly well at 900 MHz. The paper you referenced with the 82% efficiency used a dipole antenna for 5.8 GHz. The wavelength at 5.8 GHz is something like 50 mm, and they used a 1/2 wave dipole antenna (their length was around 25 mm). The wavelength at 900 MHz is 333 mm, but their SRR design was only 40 mm on a side (a 1/2 wave dipole would have to be 150 mm or so).
I don't think they were making any claims of new physics here, but probably pointing out a design that would be fairly compact and leverage all the 900 MHz EMI flying around. For what its worth, their max efficiency occurred for a resistive load of 70 Ohms, which is a reasonable load for something that you want to power with an energy harvester.
I suppose I may click through to see what the actual ad said, because the person above suggested that it was at least indirectly addressing the Snowden situation, but for years I've seen them heavily active in recruitment and even small business outreach. If you go to a technical conference expo, it wouldn't be a surprise to see them have a booth, or the CIA, or FBI, or whatever. I think most people don't realize how big of a place the NSA is. Like all other large institutions (National Institutes of Health, any of the National Labs, all universities) they have divisions that specialize in work on this or that, so this group over there might be involved in the data surveillance thing, but these groups over there are doing completely different things. Any ad from them to recruit you to come work for them is going to say you'll do real cool work, and it will have an appeal to a sense of God and country. How else are you supposed to do the sell?
The NSA advertises jobs all the time in a variety of formats. They have recruitment booths at technical conferences, internships, etc.. They have a whole web site and all. What is particularly newsworthy about this?
There are some really interesting experiments going on these days with QM behavior of macroscopic objects (micrometer-scale). I've seen descriptions of MEMS cantilevers built and they measure its vibrational modes, and these guys describe how they did it using reflected laser light. The trick is to cool the device to get rid of the phonons and detect when it falls into the ground state.
Using our best estimate for the Chelyabinsk airburst energy, of about 500 kt, we have estimated the bolide flux at the Earth over the period from 1994 to mid-2013. This estimate is based on 20 years of total global coverage by the US government or infrasound sensors, more than doubling the earlier time coverage.
The Slate article mentions there were two Nature papers, but the article summary above only gives a link to one. The papers are:
This one came up with 20 year frequency for these sized events: A 500-kiloton airburst over Chelyabinsk and an enhanced hazard from small impactors
This one looked a bunch of YouTube videos and analyzed how it broke up as it went through the atmosphere:The trajectory, structure and origin of the Chelyabinsk asteroidal impactor
The beauty, of course, is because it was so precisely ground into a wonderfully specific shape (it gave perfect spherical aberration), it was easy to make corrective lenses.
From what I know of everyday life in the US from friends and Slashdot posters . . .
You would have a very myopic view of the US in particular, and the world in general, if you are basing it off of Slashdot posters. Indeed, I can form a very clear opinion of Europeans from Slashdot posters as well, but I don't think you would find it reflects your experience.
I always found the browser search hijack to be rather annoying. That, and the majority of my fortune quotes suddenly were from someone named Husse, who nice guy and all as he seemed to be, the quotes meant nothing to me since I never interacted with him on the Mint forum.
if we don't actually need this helium reserve lying around forever, selling it off slowly seems like a reasonable thing to do.
One of the many problems with the Helium Privatization Act of 1996 is that it mandated that the sell-off was to be linear, not based upon supply, demand, or any other aspect of the marketplace. So every year the Bureau of Land Management had to sell of X many units.
The Government wasn't selling it below market cost to encourage scientific applications or for any other reason based upon intelligence, foresight, or reality. It is because Congress passed a law forcing the helium reserve to be sold off (Helium Privatization Act of 1996). The pricing mechanism worked into the law bears no relationship to the market price of helium. It was as much a horrible idea at the time as it is now. Too bad it only took almost 20 years to address.
The professor and Mary Anne,
If I recall correctly from my youthful days of rerun watching, in one (the first?) season that line was originally:
and the rest,
I never understood why they didn't name those other two.
Plus, if Spiegelman was fairly well known for this kind of research, the journal editors should have asked him or one of his colleagues to be one of the reviewers.
If it is true that they have a terrible peer review process, then I think it is very relevant to the story. They must have a terrible peer review process if the paper got published. Normally there would be several rounds of give and take between the paper authors and the journal editors and reviewers, which either wasn't done, or was done through some manner of communication such as using personal email accounts.
Better yet, they could build a big arena and everyone who goes to the arena could float up in the air before they vaporize. At birth we could implant a crystal in everyone's hand, and when their crystal starts flashing, that's when they know to go to the arena. The criteria for when their crystal flashes, we can figure that out later. Base it on their age or something ....