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The U.S. military already has one of these

It's used in inertial navigation for weapons systems. Interestingly, the inertial navigation software itself is available as source code for download, but the data of the map itself is classified to prevent its use by non-U.S. aggressors. Also, for what its worth, the military data resolution is far better than the 100km between data points, as it is with GOCE, but is the resolution falls off on non-projected weapons trajectory route splines.

See also the geoid from the earlier GRACE observations (animated spinning globe) which were 322km resolution, along with a more technical discussion of GOCE:

        http://www.scientificblogging.com/planetbye/grace_goce

-- Terry

Of course it's a hack! So is "dark energy". I know Physicists don't think too much about philosophical or meta-physical implications of theory; they're very practical men (and women). If the mathematics work and agrees with observation, then they're good to go. The problem is when there's no observation to either agree or disagree with, or when the observations they're developing models for are actually wrong. That is why many of these people do what is called "theoretical physics". Of course sometimes observations are made that contradict current theoretical physical theories. When this happens my raised eyebrow can be justifiably lowered (for a moment).

I worry about "Chicken Little" syndrome with space weather alerts. "GPS will die, sending airplanes crashing and sinking boats. Cell phones will fail, stranding travelers and resulting in people in remote areas dying due to exposure. Worse of all, our TV may go out for a few hours."

Jay Reich from the Dept. of Commerce talked about 'overwarning' versus 'need for science', covered at http://www.scientificblogging.com/daytime_astronomer/why_sky_falling_space_weather_communications but here's the summary:

Science is rigorous, slow, based on data and challenge. This means politically it's horrible, and the media overstates it. So we have to balance warning with overhyping and risking people tune us out. Solution? Unknown.

The whole concept is a farce. The "research" upon which this test was based in fraudulent. Sad.

http://www.scientificblogging.com/rugbyologist/festival_idiots_3_andrew_wakefield_vaccines_and_autism

They have one, it's called RepRap.

If you want to go the mad scientist route, build a satellite in your basement. It's about the same cost as buying a motorcycle ($8K including launch) and, as far as mid-life crises go, a lot cooler. I'm doing it ( http://projectcalliope.com/ ), and blogging about how it goes at http://scientificblogging.com/satellite_diaries

You get to learn neat stuff about electronics, Arduino-level programming, and HAM radio.

It's worth it just for when people ask what I do for fun...

and as we know leaders in the field are never frauds.. oh wait!

And here as well: http://www.scientificblogging.com/quantum_diaries_survivor/plot_week_news_cp_violation

Crossing the "event horizon" isn't really an interesting event in and of itself. It just marks a point of no escape and no return. Granted, if you're getting close enough to the black hole to be anywhere near the event horizon, the tidal stresses might be pretty intense, but the horizon itself is not a solid object and likely somewhat boring.

Also, supermassive black holes generally have remarkably low densities. A 6.5-billion-Sun black hole has a density of about "0.5 mg/cm3, less than half the density of earth's atmosphere at sea level."

This is why I personally only launch eco-friendly and organic all-wood satellites. :)

This is why I personally only launch eco-friendly and organic all-wood satellites. :)

Trucking companies aren't known for their fresh and new approach to... well, anything really.

But it doesn't have to be that way. Computer science is really about thinking carefully about a method of doing something. Logistics are very important to trucking companies, and if there's one thing that computer scientists are good at, it's logistics.

The new hot theoretical speculations hold that gravity is a thermodynamic effect too, not a regular force. This dude explains.

Still highly speculative, mind you, but definitely hot stuff.

The equation Einstein came up with more than a century ago can be considered a degenerate form of the mass-energy-momentum relation for vanishing momentum. Einstein was very well aware of this, and in later papers repetitively stressed that his mass-energy equation is strictly limited to observers co-moving with the object under study. However, very, very few people seem to have paid attention to Einstein's warnings, nor to any of the more recent warnings. Even worse, the vast majority of authors of popular science books take great liberty in applying E=mc^2 to objects moving at speeds close to the speed of light, and then declare mass to increase with velocity in an attempt to recover consistency in what has become an incoherent mix of relativistic and Newtonian dynamics. Theoretical physicist Lev Okun refers to this practice as a "pedagogical virus". ..... What I consider truly amazing, is how few people are aware of the mass-energy-momentum relation.

-- What's Wrong with E=mc^2, The Hammock Physicist.

Our blogger then proceeds to draw a right triangle with sides E*v, E*c, and m*c^3. For velocities (v) of 0, E*c=m*c^3, or E=mc^2. Yay vectors.

So in the new model, temperature differences in the space around the sun, 4.6 billion years ago, caused Earth to migrate outward as much as gravity was trying to pull it inward

Or, perhaps, gravity could be a consequence of temperature differences, so the "pull" and the "push" don't really happen.

From http://www.scientificblogging.com/hammock_physicist/holographic_hot_horizons the first of the two blog entries:

The value for G comes out correctly if you enter for Abit the value corresponding to a Planck area. However, the Planck area (G/c3) is defined in terms of Newton's gravitational constant G. Have we not introduced a circular reasoning here? I am actually not sure.

This does seem like an issue. However, it looks like you can do this with G as a variable. The upshot then is not that you get the right value for G at the end but that you get Newton's inverse square law (up to a scalar) which by itself would be really impressive even if one can't a priori get the value of G.

Obligatory disclaimer: I'm a math grad student not a physicist so I could be completely wrong here.

http://www.scientificblogging.com/mark_changizi/why_doesn%E2%80%99t_size_matter%E2%80%A6_brain This has been proven over and over that size doesn't relate to smarts. An elephant's brain is just over 3 times larger than ours and yet I didn't see any elephants walk on the moon or develop great civilizations.

Recommended reading: The God Particle by Leon Lederman. He was head of CERN for a while and won his Nobel prize for discovering the bottom/beauty quark at Fermilab. This is THE best book I've read on the topic. Just bear in mind that when he wrote it the SSC was going to be the next big project and LHC is largely fulfilling that role instead, as it turns out.

The period of observation isn't really a factor, because one of the things that makes this tricky is that the heavier particles such as the hypothetical Higgs decay into something else very very quickly anyway.

You don't observe these kinds of particles directly; you see the cascades of particles that they decay into pass through your detector, and then you prove that the only way that combination of particles could have appeared travelling in those directions is if they are the product of the hypothesised particle.

This article talks about how Fermilab recently went through this process for a top quark, which is a pretty similar deal. The top quark is a heavy particle you won't see in most interactions until you get to some pretty big energy densities, just like the Higgs; the difference is the energies are somewhat lower, so Fermilab has got there already.

CMS and ATLAS are both designed to ensure you detect EVERYTHING known that comes out of the collisions so you can also work out what went straight through your detectors, by looking at what energy has not been accounted for in what you picked up.

Or, there might be a whole other bunch of particles produced at 7 TeV, and no Higgs at all; plenty of papers have been written on what you might expect to see instead. Other explanations for inertial mass are available.

---

LHC Feed @ Feed Distiller

Sadly however, people will read this article and will still freak out about how the LHC is going to doom us all.

Still, the LHC *can* make an fairly impressive mess of the test chamber area something goes wrong. I'd recommend being at least a few miles away from it while it's running.

http://www.scientificblogging.com/big_science_gambles/interview_professor_otto_rossler_takes_on_the_lhc
And interesting discussion on this that I found. It's very likely that the resulting explosion would "save the planet" as a side effect, but make for a very impressive crater as well.

I wrote up some notes from a NASA lunch meeting on this, titled (not too originally, I admit) 'The Petabyte Problem'. It's at
http://www.scientificblogging.com/daytime_astronomer/petabyte_problem. It's not just a question of thinking on the 'Internet scale', but about massive data handling in general.

What makes it different from previous eras (where MB was big, where GB was big) is that, before, the storage was expensive, yes, but bandwidth wasn't as much of a trouble for transmitting, if even locally. You could store MBs or GBs on tape, ship it, and extract the data rapidly-- bus and LAN speeds were high. Now, with PB, there's so much data that even if you ship a rack of TB drives and hook it up locally, you can't run a program on it in reasonable time. Particularly for browsing or inquiries.

So we're having to rely much more on metadata or abstractions to sort out which data we can then process further.

Vaccination is often all or nothing. Call it tyranny of the majority if you like-- most of us want to live. Deal with it.

Vaccination is NEVER "all or nothing".

If the vaccination works, you won't get sick, no matter what the rest of the world does. So why do you believe forcing it on everyone is a good idea?

I call bullshit. Citation, please.

It's easy to "call bullshit" when you're completely ignorant of a subject, and just insist on enforcing your dogma on everyone else...

On the off chance that you do actually want an opportunity to edify yourself:

Do flu shots for the elderly save lives? Just washing hands works better, says study.

http://blog.nj.com/njv_thurman_hart/2007/12/a_useless_vaccine_mandated.html

http://www.globalhandwashing.org/health_impact.htm

The art looks dark, yes, but then, the famous "Fantasia" segment of Mickey as the Sorcerer's Apprentice was plenty dark, too. So they're keeping the right spirit, I think. Mickey isn't always hearts and violets. Sometimes he's a cunning tactical schemer, and sometimes he's a pure force of chaos... who always means well.

Me
blogging at http://scientificblogging.com/sky_day/

As a scientist, I run into the mental block many people have that 'science is hard', which means anything scienc-y I say is treated like it's in another language. For example, I wrote my family and friends:

        I'm launching a satellite for fun, to make music from space. It's called Project Calliope, and I'm writing about it up at: http://scientificblogging.com/satellite_diaries/feed

        It's pretty much just me, with some friends helping with different parts of it, and a couple of sponsors helping cover costs (hopefully). I'll be the first to admit it's unusual, but I've always wanted to be part of the space race.

And I received one particular reply of:

        Hi-in English what does this actually mean??Sounds, well , different

The answer in English is, "I'm launching a satellite for fun, to make music from space." That's really it. No deep analysis or technobabble needed.

The solution, I think, is hamsters. Everything is easy to understand if there's a cute animal. Had I said "I'm launching a hamster into space", everyone would say "cool!" or "weird!", but at least they'd get it.

...
competition forces companies to eventually lower their costs. with robots and computers being able to do more and more human jobs, it seems like a good idea to fire workers and have them replaced.

on the surface it seems like a good idea - but high unemployment, which eventually follows, has never been good for any economy.

it won't bring on a new era of prosperity, as less people will be able to buy their products. this forces companies to lower prices even more (ie firing workers, using technology instead), which again hurts purchasing power. A lovely vicious circle ending in the very rich getting richer and society's bottom 50% starving. ...

This kind of argument has been used since the 1700s industrial revolution. Ever hear of Luddites? Or Featherbedding? There is a dislocation. Older workers have a hard time adapting and being retrained for new technology and adapting to a new environment, and yes there is a lot of suffering, and I don't want to be dismissive of that. But the end result has not been 'the very rich getting richer and society's bottom 50% starving."

I will also allow that if the singularity happens, if machine intelligence genuinely surpasses human, then everybody may be out of a job. It would be a singularity or at least an inflection point. But what should be done about it? Should we always hold machines back so we can claim our top dog position.

One thing that seems to be true of human nature is that people generally would prefer to be the big frog in a small pond, rather than a comparatively less big frog in a bigger pond even if they're bigger in absolute terms. Some economists and policy makers talk about how 'a rising tide floats all boats', but for a lot of people, if their particular boat isn't floated high enough vis a vis others, they'd prefer the status quo.

50K years from now, do we want humans to still be smarter than the machines? One alternative might be 'trans humans', enhancing our own intelligence through artificial means, or combining with machines into cyborgs. I would say that runs into the "ship of theseus' paradox:
http://www.scientificblogging.com/geeks039_guide_world_domination/cool_thought_experiments_ii_ship_theseus

also the obligatory wikipedia URL: http://en.wikipedia.org/wiki/Ship_of_Theseus,

> I am currently going through a Neil deGrasse Tyson phase.

I became a fan of his after his "Astrophysicists Killed the Dinosaurs" talk:
http://www.scientificblogging.com/daytime_astronomer/astrophysicists_killed_dinosaurs_neil_degrasse_tyson_science_communication

Because there are sound commercial reasons to do so.

Which vary in each specific instance, while the figure itself remains largely unchanged.

It boils down to human counting systems with only three or four distinct values: 0%, 1%, 90%, 99% aka nobody, hardly anybody, most people, almost everyone.

When you cite 1% it spares you from deciding whether to write "hardly anyone" or "a tenacious few". For exponential distributions, 1% is the glass half-full point: the optimists read that as the upward inflection of immanent domination; status-quo pessimists read that as annoying cohort who forgot to take their meds.

If you write "5% of desktops run Linux", it's like saying the glass is 5/8s full. It only complicates the knee-jerk response.

If some materials science wonk invents an exotic new material which they have absolutely no idea how to commercialize, but raised money anyway, the obligatory quote is that commercial products will be available "in five years". It's kinda PR speak for "don't call us, we'll call you, if we ever get our shit together".

There are sound reasons not to take precision too seriously.

http://www.scientificblogging.com/quantum_diaries_survivor/nitpicking_omega_b_discovery

Not to mention that we are making judgements about 100000 year temperature (and composition) cycles based on 200 years of data, completely ignoring the other ~4.55 billion years. These judgments fly in the face of paleological evidence showing the earth has been much hotter than now in the past, in a repeating cycle, long before man existed.

All we really know is that the global temperatures are rising. We have no idea why. Anyone that claims they do has a political agenda or hasn't bothered with the paleological record or the Milankovitch cycle.

I'm all for green energy etc, but predicating it on global warming is fallacious and misleading. "Because we will run out of oil in less than 100 years, need sustainable energy, we fight wars over oil, fossil fuels are filthy, and hydrocarbons cause cancer" are much better reasons, factually correct, and are scarier because we have valid evidence to support them as opposed to "Wolf!", which is based on a data set tailored and limited to fit the "man caused global warming" argument and political agenda.

Nobody is denying climate change. What is at issue is the cause of the climate change. The only acceptable answer is "We don't really know, but the *evidence* says it's been much hotter and much colder in the past, and climate change is part of the earth's natural processes".

That's all we can prove.

It's very irresponsible (in many ways) to misrepresent a theory as fact before it's been proven.

I don't think any climate scientists are idiots. However a lot of them are supported by government grants, so they have a conflict of interest. There are many cases where scientists that disagreed with the bandwagon have had their funding cut.

http://www.scientificblogging.com/news_releases/climate_scientist_consensus_global_warming_real_other_scientists_not_so_much

Hi,

>So you can fairly easy detect it and have enough time to calculate when and if it will hit

Actually, no. Most detections occur after the fact, not in near-real time. So we're not predicting them, we're backtracking after we notice one.

You can't see a CME head on, only from the sides (it's "optically thin"). So you can't see the ones that hit Earth if you're viewing from Earth (that's why there's the STEREO mission, to look off the earth-sun line).

And, they don't travel at a uniform velocity. Current predictions are only good to +- 12 hours. So for an event that takes 1-4 days to arrive, you have a +- half day window. That's pretty big. Current modeling with STEREO might be able to get that down to +- 4 hours, soon.

And it turns out it matters which magnetic field orientation it has-- a small CME with field aligned opposite the Earth's is far worse then a big CME with the field aligned. Fortunately there's a lot of work to use magnetogram images to predict the orientation.

All that combines to define the 'geoeffectiveness' of a given CME/solar storm.

Hard to detect the earth-incident ones, and hard to predict. Fun to study, though!

me
http://scientificblogging.com/sky_day/

The National Forensic Association is an intercollegiate debating organization. I doubt they have anything particularly important to say about the JFK assassination. There was a report by the National Academy of Sciences based on acoustical analysis of crime scene recordings, but it concluded that the multiple-shooter theory was not supported by the available acoustic evidence.

Perhaps you are thinking of a report by a Texas A&M professor of statistics and a retired FBI forensic scientist from 2007 who "conducted a chemical and forensic analysis of bullets reportedly derived from the same batch as those used by suspected assassin Lee Harvey Oswald." Their conclusion was that the bullet fragments aren't particularly rare and that the matching fragments could have come from three or more separate bullets, and that previous analysis based on bullet fragments "used to rule out a second assassin is fundamentally flawed."

The important thing to note here, conspiracy buffs, is that those two reports don't contradict one another. There could be a second shooter that wasn't captured by the acoustic evidence -- but likewise, matching fragments could have come from three or more separate bullets is not an equivalent statement to "matching fragments did come from three or more separate bullets."

It's also worth noting that, in fact, the report was not done by a "national association," it never made the sweeping claim that "the official story was impossible," and the report has been criticized for naive use of statistics and generally poor writing. According to critic John Fiorentino, the paper as finally presented in 2008 was revised to address his rebuttal linked above, and "by making the revisions, the authors have effectively negated their findings just as stated in [Fiorentino's] rebuttal."

There are many criticisms to be made of the Warren Commission's handling of the investigation, and I suspect that because of that there will be people arguing about this two hundred years from now. The problem is the same here as with nearly all Grand Government Conspiracy Stories, though: even if the official story (about whatever event we're talking about) is incomplete and imperfect, that doesn't ipso facto make the official story wrong in either overall scope or final conclusion. It's worthy to question authority and to be skeptical of any official story--but there is a point where skepticism becomes gullibility: someone who automatically dismisses anything The Government says is thinking no more critically than someone who automatically accepts anything The Government says, and is ultimately just as easy to manipulate.

As a researching using STEREO data, I wrote a piece on some of the logistics of this, and what we may find.
http://scientificblogging.com/daytime_astronomer/secrets_l4l5_gravity_wells

The summary is: we've already seen a bit in an earlier roll so we know there's stuff there, we lose use of the in-situ to explore L4/L5 so we have to balance that with our core science, there's a higher risk to the detectors due to dust, but what the heck, we have to pass through it anyway. We may find any of: dust, the moon's progenitor, and earth-killer, more dust.

Good points. On SOHO-- as you note, SOHO has been camped out at L1 and provides about the same advance notice as WIND. So their statement that WIND gives earliest notice is a little... off.

That said, STEREO-B (and A) aren't on the Earth-Sun line, so you can argue the in-situ measurements aren't quite the same. But I'll go with your argument, since STEREO-B does give advanced notice.

Not to put down WIND-- it does its job well. But there's no need for the article to put down existing missions, let it stand on its own merits.

me
Daily life as a STEREO post-doc at http://scientificblogging.com/sky_day

Oh, sure, it sounds good, but what if the hoses rupture while you're being towed over the ocean-- that's straight water pouring out, at tens of gallons per second! It'll get all over everything! And what are the people running it going to do then, when there's suddenly water all around them? Float? Didn't anyone think this through?

This does sound seriously fun... and smart too. Shades of Armadillo's EPA visit for their earlier hydrogen peroxide rocket, paraphased "what do you do if there's a fuel spill" 'We run away!' "That's not acceptable containment of contaminents!!" 'Sure it is, it'll turn to water and air' "Oh, cool!"

***
want some astronomy? http://scientificblogging.com/sky_day/

Actually, those two journals are print journals I normally pick up in a bookstore. As for online sources, I'm not aware of any academic journals that are freely available online (unfortunately). For free online stuff, reading a nice variety of newspaper-like sites is probably as good as one can get. A few worth reading:

Science:

Eurekalert, Scientific Blogging, National Academies

Politics/Current events:

Moscow Times, Al Jazeera, PressTV, YNet, UN News Service, People's Daily

All this plus heavy use of Google News with custom sections, of course.

None of this is as good as the journals, but it's more current.

That's not what they're arguing. They're talking about a 4,000 year old earth, and dinosaurs with saddles.

In any case, it's more subtle than just saying God 'created' evolution. Prior to the theory of evolution, the watchmaker analogy was perfectly good at reconciling God with the fact that we observe the universe following natural laws. The problem is, evolution provided a natural mechanism for those things taking place, at least as far as biology was concerned. If there's a natural explanation, why bring the supernatural in?

If every time someone discovers makes a scientific discovery, we're content with "God made it that way", then does God mean anything to us?

You found out what 10% of the brain does (the sensory/motor areas)? The other 90% must not be used for anything.
[...]
You'd have a good point ... except that no serious researcher in neuroscience or genetics has ever claimed either of those things.

Yep. This should be modded up.

For example, the "unused brain" thing has never been reliably attributed to a real scientist. Basically, it was made up by the media.

OTOH, I do believe that many geneticists did originally believe that the so-called junk DNA served no useful purpose. See this article, which suggests that at least in the 1970s there was a common belief among geneticists that at least some DNA served no practical purpose other than to replicate itself. It wasn't until about 10 years ago that we started finding actual practical uses for the so-called junk DNA, so presumably that belief persisted at least until then.

It is, however, fair to say that it has never been scienctific consensus that all junk DNA is useless. But saying that no geneticist has claimed it would be foolish, as I'm sure enough digging will turn up at least some such claims: it was until relatively recently a plausible, if extreme, position.

There is a massive amount of research into cancer, and yet there is no "golden bullet" to cure cancer.

Cancer Cured? Granulocytes Treatment Worked 100 Percent In Mice But Will It Work In Humans?

Depends upon the way the system is working. Does it track the position of a single person and adjusts the view accordingly? Or are there multiple GPU's rendering the scene from different angles and having these different views projected in different directions using vertically aligned lenses? In the latter case, projecting a view "outwards" should be possible. It certainly looks the case in the gears video

I wonder if this technology would scale into a laptop display?

Researchers did a study on primitive surgical techniques. They found out that the caves used for these operations were as far back as possible, meaning that the air was dry and had no dust. Also, whenever a flintstone was used as a cutting instrument, a brand new stone was split, so there was no bacteria on the surfaces of the stone.

Ancient Brain Surgery

I need trepanning like a hole in the head.

This quote, about how science is actually done, is one I put on my quotable quotes page. It's worth reminding people that the "eureak" model of science is a little bit simplistic.

"The work of real science is hard and often for long intervals frustrating...
"Keep in mind that new ideas are commonplace, and almost always wrong. Most flashes of insight lead nowhere; statistically, they have a half-life of hours or maybe days. Most experiments to follow up the surviving insights are tedious and consume large amounts of time, only to yield negative or (worse!) ambiguous results.""

-Edward O. Wilson
"Scientists, Scholars, Knaves, and Fools," in American Scientist 86 (1998)

But, as has been pointed out by Michael White, journalism is more about a "good story" than about accuracy about how science is done.

And according to this link (no myminicity, I swear!), Helium is in danger of being in short supply due to among other things that it's not captured and recycled after use and while being available in big supply in the universe, the Earth supply is actually a bit limited.
According to the article it is an issue the next generations of scientist are going to have to struggle with. So maybe a Helium-based airship is not that good an idea, although I don't have to background to propose a different scheme.

Also Roland doesn't play nice when it comes to photographs. Please compare http://www.scientificblogging.com/news_releases/helium_isotopes_may_uncover_new_geothermal_energy_sources with Roland's blog: http://www.primidi.com/2007/12/02.html#a2025. Btw van Soest has apparently been working on this subject for some time. Check out his publications list on his personal info page http://www-esd.lbl.gov/ESD_staff/van_soest/index.html

The original link works for me

'Stealth' Antenna Made Of Gas, Impervious To Jamming
Submitted by News Account on 12 November 2007 - 2:58pm.
Physics

A new antenna made of plasma (a gas heated to the point that the electrons are ripped free of atoms and molecules) works just like conventional metal antennas, except that it vanishes when you turn it off.

That's important on the battlefield and in other applications where antennas need to be kept out of sight. In addition, unlike metal antennas, the electrical characteristics of a plasma antenna can be rapidly adjusted to counteract signal jamming attempts.

Plasma antennas behave much like solid metal antennas because electrons flow freely in the hot gas, just as they do in metal conductors. But plasmas only exist when the gasses they're made of are very hot. The moment the energy source heating a plasma antenna is shut off, the plasma turns back into a plain old (non conductive) gas. As far as radio signals and antenna detectors go, the antenna effectively disappears when the plasma cools down.

Picture:
http://www.scientificblogging.com/files/plasma%20antenna.jpg

This prototype plasma antenna is stealthy, versatile, and jam-resistant. Credit: T. R. Anderson and I. Alexeff

The antenna design being presented at next week's APS Division of Plasma Physics meeting in Orlando consists of gas-filled tubes reminiscent of neon bulbs. The physicists presenting the design propose that an array of many small plasma elements could lead to a highly versatile antenna that could be reconfigured simply by turning on or off various elements.

- T. R. Anderson and I. Alexeff
2007 APS Division of Plasma Physics annual meeting
November 12, 2007

So uhh.. how does this prevent jamming?
Because you have a broader range of frequencies to hop?