iObserve... makes your preparation of astronomical observations a breeze. It gathers automatically and easily all the information you need when observing the sky with small and big telescopes. It has been built from the ground up by an experienced professional astronomer.


iObserve allows you to:

• 

• Resolve an object coordinates with SIMBAD

• Access automatically its aliases, magnitudes, and NASA ADS references

• Display the equatorial, celestial, galactic coordinates, in whatever epoch and units

• Access the ViziR catalogue pages, and ADS abstract page.

• Draw its airmass curve for for about 90 builtin observatories on Earth

• Draw simulatenously multiple airmass curves of different objects for comparison

• Get the table of the selected objects sorted according to their time of minimum airmass

• See the Moon's airmass curve in place, and its minimum separation to any object, when relevant

• Observe the airmass curve over a night whose length and shift can be largely customized to even satisfy radio astronomers!

• Slide easily the night date to match future's observing dates

• Find automatically for you the closest Landolt and UKIRT standard stars

• Know how much time an object spends above a given altitude during the night

• Get the time and length of the nights for 4 different twilights limits

• Perform searches in the object's references



If you have your own astronomical observatory, being a remote amator or professional observatory, or simply your backyard, simply enter its coordinates, and you will be able to use it like any other builtin observatory.



iObserve also provides its famous times bar with Local Time, UTC, (Modified) Julian Date and the Local Mean Sidereal Time of an observatory you can choose.



Note for 0.8 beta users: An Upgrade Process will take place during first launch. It will keep your current objects, and export Observing Runs and Night Logs to a safe place before being removed.



A place to store astronomy-related websites is also provided, as well as a full-screen mode.

Version 1.0.2:

• 

• Fixed the completely wrong Moon airmass curve with new algorithm from textbook "Astronomical Algorithms", validated with Unit Tests and comparison with Xephem values. Differences of a few arcminutes have been detected with Xephem, despite perfect accuracy with textbook example. 

• Fixed the wrong UTC and LMST values in the tracking window of airmass plot. 

• Fixed an issue where the name of the standard star folder was renamed in place of the star's. 

• Fixed a problem occuring when creating a new observatory, and that was causing the app to hang or crash. 

• Fixed the missing negative galactic altitude sign (was never visible) 

• Fixed the wrong NASA ADS quicklook abstract page displayed when references are filtered with a search. 

• Fixed a problem where SIMBAD returns more than one object for a given input, that was causing the app to hang or crash. 

• Fixed the missing refresh of the star name in the airmass plot when changing the name of a star. 

• Fixed an issue where a standard star could be deleted and never recovered. 

• Fixed the wrong recovery of objects present more than 1 time in the list (for objects with equal name and coordinates). 

• Fixed a nasty bug that was screwing the correct number of standard stars saved on disk. 

• Corrected the wrong "m" and "s" units in declination coordinates. 

• Added the possibility to import a list of stars from a file, optionaly containing the coordinates. The whole import mechanism has been improved. 

• Added buttons "Open in iObserve" and "Open in Papers2" to the NASA ADS QuickLook window. Papers2 is an app by mekentosj.com. 

• Added the possibility to transform coordinates to B1950 epoch. 

• Changed the SIMBAD webpage to that of the new SIMBAD CDS Portal. 

• Improved the Help (although it is not finished). 

• Improved stability when accessing a star already saved. 

• Improved the coordinates precession algorithm. 

• Improved the drag & drop of separators. 

• Improved the reliability of deleting folders of objects, and mix of objects and folders. 

• And the usual "additional various UI and stability improvements"

Mac OS X 10.6.6 or later.

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Two analyst reports claim that a large majority of customers waiting in line for yesterday's US iPhone launch were repeat customers. According to Piper Jaffrey’s Gene Munster, 77 percent of those waiting in line already owned an iPhone, while Oppenheimer analyst Yair Reiner found a very similar 76 percent of customers in the same boat. According to the Oppenheimer numbers, the average length of time before upgrade was 14.7 months.

Munster, who polled a total of 608 people across San Francisco, Minneapolis, and New York City, also found that 16 percent of the line dwellers were making the switch to AT&T from another carrier. A little more than half of iPhone 4 purchasers were there for the phone with the highest storage capacity. That's up from 43 percent in 2009, but it doesn't reach the astronomical mark of 95 percent when the original iPhone launched in 2007.

Reiner estimates that Apple will sell 1.5 million iPhone 4 units during the launch, a number which would trump last year’s iPhone 3GS opening weekend sales by 500,000. At the same time, Munster claims the launch numbers are largely irrelevant due to the brand loyalty that Apple has assembled over the past three years. 

He points out that what's much more important than opening day numbers are the hordes of iPhone users who continue to upgrade as their contracts expire, despite vocal displeasure with AT&T service in some regions. 

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"Mortal as I am, I know that I am born for a day. But when I follow at my pleasure the serried multitude of the stars in their circular course, my feet no longer touch the Earth." -Ptolemy

When you look up at the stars in the night sky, perhaps the most striking thing that they do is rotate about either the North or South Pole, depending on which hemisphere you live in.

But what do you get if you look up at the same time each evening, night after night?

Well, unlike the planets Mars (in red) and Uranus (faint, to the upper right of Mars), the stars stay in the same exact spot from night to night. Yes, they're moving, but they move far too slowly for how far away they are to detect their motion.

So how would you determine how far away a star is? Well, if your name was Nicolaus Copernicus, you'd look up at the positions of the stars at one night, and you'd look up six months later, and see if any of the stars have moved.

Why would you do that? Play along with me for a moment. Close your left eye, and hold your right arm out straight, with your thumb pointing up. Pay close attention to where your thumb appears to be relative to everything around you.

Got it? Good. Now, leaving your thumb in the same exact spot, open your left eye and close your right eye. Notice where your thumb appears to be now.

It appears to move! You can play with this all you like, but you'll not only notice your thumb always moves when you switch eyes, it appears to move by a fixed number of degrees dependent on two things only: how far away your thumb is from your eyes and how far apart your eyes are! In astronomy, we call this parallax.

Back to the stars now. When you make an observation of the stars, your eyes are way too close together to see any sort of "apparent shift" of a star. In fact, the diameter of the Earth is far too small! But Copernicus, realizing that the Earth goes around the Sun, would have seen his position shift, over the course of six months, by about 300 million kilometers! So, he reasoned, he should be able to see the closest stars in a different apparent position, like so:

Of course, Copernicus didn't see anything because the telescope hadn't been invented yet! The first astronomical parallax wasn't discovered until 1838, and that was by Friedrich Bessel.

(And yes, for those of you who are wondering, it's the same guy who did Bessel Functions.)

Once you can measure the parallax of stars, the one with the largest parallax will be the closest one to you. (And if you want the answer, it's Proxima Centauri, at 4.2 light-years distance.)

But what if you lived before 1838? What if you still wanted to know the distance to the stars; would you have any recourse?

Not until the mid-1600s did someone -- Christiaan Huygens -- make some great progress on that front. Huygens was already famous for inventing the pendulum clock and discovering Saturn's rings and its great Moon, Titan. But the stars were another story. Huygens' big idea was that the stars in the sky were identical to our Sun, but much farther away.

Since he knew how bright the Sun was and how far away it was, he reasoned that if he chose the brightest star in the sky and was able to figure out its brightness relative to the Sun's, he could figure out its distance!

So he found the brightest star in the sky, Sirius, and studied it.

The next day, he went and took a large brass plate and drilled holes of different sizes in it. He held the disc up at arms length, covering the Sun entirely. Well, except for the holes he drilled in it! And so he studied the tiny bit of Sun poking through the holes, looking at progressively smaller and smaller holes until he found one that matched Sirius.

At least, that was the plan. It didn't work, though. No matter how small he made the holes, the tiny bit of Sun that shone through was always significantly brighter than Sirius! So what did he do? He went out and got a bunch of opaque glass beads, reducing the amount of light that came through even further.

And it wasn't until he reduced the amount of light coming from the Sun by a factor of about 800 million that he was satisfied. This meant that -- roughly -- this star was 28,000 times farther away than the Sun was from Earth!

If you work this out in modern units, his estimate comes out to about 0.4 light years. But if you head on over to wikipedia, it'll tell you (correctly) that Sirius is 8.7 light years away. But it will also tell you that Sirius, intrinsically, is 25 times more luminous than the Sun is!

In other words, if you know something about how intrinsically bright a star is, you can figure out how distant it is without a telescope, and just by creatively destroying one of your dishes!

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The metric system's biggest appeal is it's base unit of 10. 10's are just a whole lot easier to work with. For scientific measurements, 10's make it easy to calculate changes in orders of magnitude (that is, from millimeters to centimeters to kilometers instead of trying to do the math in feet or miles). Tens are just easier to manipulate. We have ten fingers and ten toes. We (in the US) use a base unit of 10 in our monetary system.

So why not make our days, hours, minutes and seconds into units of ten as well?

As it turns out, we almost did. The metric system, in a slightly less evolved state than what it is now, was adopted in France shortly after the French Revolution around 1789. The basis for the metric system had been around for about 200 years, but France's adoption snowballed into an almost world-wide change over to metric.

The Revolution lasted about ten years and saw the centuries old French monarchy toppled by civilian uprisings and replaced by a democratic system. Adopting metric was not only practical, it represented getting rid of the old regime and starting fresh. French leaders then decided to also make a calendar based on units of 10, and recruited mathematicians and scientists to help put it together (this included enlisting the help of Joseph-Louise Lagrange, whose name should be painfully familiar to calculus students).

The new calendar, known as the French Republican Calendar divided a year into twelve months (three for each of the four seasons), each made up of three 10-day weeks, with each day divided into 10 hours, divided into 100 minutes, divided into 100 seconds. So one of these new hours was actually about 144 minutes, or more than two traditional hours.

That didn't last long, for a number of reasons. I have my theory.

I'd have to argue that the calendar, measurements of time, are much more ingrained in our day to day lives than measurements of distance, length, mass, ect. Many people, including physicists, make up their own measurements to suit what they are measuring, or use comparison as often as exact measurements. For example, if I am trying to tell someone the distance between two locations, I often tell them a unit of time. It's 30 minutes away. What I mean is it's, assuming we are using the same method of transportation, this is how long it will take you to get there. That is often more valuable than distance. Have you ever used an object as a unit of comparison rather than an exact unit? Something was as big as a softball, a car, a house. Often times this is just easier than giving specific units of mass and size. Physicists have also come up with abbreviated measurements for values they use frequently. In the realm of the very large or the very small, traditional units (even with those handy units of 10) aren't always helpful. An Astronomical Unit is the distance from the Earth to the sun, and this is often better than giving the distance in millions of kilometers.

But this seems to be less often the case with time. There are units of time used in physics to refer to incredibly small or incredibly large lengths of time, but I would argue that these are used less often than in the case of other units. There is, for example, the Galactic Year, equal to 250 million years, but I don't hear this tossed around a lot. When talking about the universe, we still say that it is 13 or 14 billion years old (even though that time frame is difficult to grasp), but we measure its distance in light years, not kilometers, to make it easier to understand. The very smallest unit of time we have measured is the attosecond, or 10^-18 seconds. At that scale we are still using seconds, yet most chemists and physicists use angstroms when talking about measurements of length around 1x10^-10.

And of course that's not the only reason a new calendar would change things. It would mean the restructuring of some key elements of society, namely the work week. And there is also the religious pull - the Bible holds a seven day week, and in doing so keeps Sunday holy. Unless we wanted to continue to make a day of rest every seven days, which would make "Sunday" actually take place on various days during the week, we'd have to extend the week to ten days. Or, we could have shortened it to five, which would have been nice, but maybe not practical.

The calendar, though ultimately impractical because of how deeply entrenched the Gregorian calendar is in our lives, had some interesting aspects. In the way that the Christian calendar assigns some days to Saints, it assigned every day of the year with some thing. Days ending in 5 were assigned an animal. Days ending in 0 were assigned a tool, and all other days a plant or animal. Had this taken off we would have had The Day of the Cauliflower, The Day of the Blueberry, and The Day of the Marshmallow. You would also see these fun days: the potato, the vat (a tool?), the spinach, the corn salad, the hedge mustard, and the button mushroom. Today would be The Day of the Duck.

The French leaders also tried to divide a circle into 400 degrees, instead of 360 degrees. So instead of doing a 180 on someone, they would say you did a 200. Instead of 90 degrees to a right angle, there would be 100. The mathematician, physicist, sailor, and all around busy guy Jean Charles de Borda spent a lotta time building a new compass to go with the new system. But in the end it didn't stick. With a change like that to the foundation of geometry, you also have to change all of your logarithms and geometric functions like sine, cosine and tangent. As if that stuff isn't tricky enough as it is. And to be honest, dividing a circle into factors of 10 doesn't really make things much easier, since 100 isn't nicely divisible by thirds, which appear quite frequently in geometry. Still, for his good efforts Borda had a crater on the moon named after him, so it wasn't a total waste.

Happy Day of the Duck!

The latest Nintendo-published downloadable game for the DS may be one of the worst-named Nintendo games of all time. It's also another proof that top Nintendo-affiliated developers could school a lot of iPhone game creators.

Link 'N Launch is a DSiWare game from Intelligent Systems, the development studio behind such Nintendo-published greats as Advance Wars, Fire Emblem, and the Paper Mario series. For their second DSiWare game, IS has made a variation on the pipe-linking game Pipemania, a clever offering of linked puzzles that all involve connecting paths of pipes between fuel sources and and a rocketship, each "level" of this puzzle game resulting in the rocket being fired only as far and as on course as the player's pipe-arranging enables it.

Loved
Tough-To-Describe Strategic Sci-Fi Puzzle Gameplay: The game's main missions require that a rocketship be shot for a set distance through space, toward a planet far away. Satellite dishes need to be delivered, or something. To get the rocket there, the player must solve puzzle challenges along the way, each completed challenge serving to boost the rocket further along. The challenges involve connecting puffs of space fuel on the DS' lower screen to any or all of the rocket's three boosters that are rendered right at the top of that screen (the top screen shows the rest of the rocket and hints about the best path to send the rocket on next) .

In the playing field are square pieces, each of them displaying a straight, curved or branching piece of pipe. With the deft swipes of a DS stylus, these pieces need to be twisted, flipped and moved in order to connect fuel to rocket. Once the connection is made, the fuel flows and the rocket launches a few astronomical units of length further toward the destination planet. As the rocket slows to a stop after its latest push, the player has to arrange a new set of pipes to push the rocket forward again. As the rocket journeys further into black space, the challenges get tougher. The pieces available and the paths that need to be made to join fuel and rocket are increasingly complex. The whole endeavor toughens as the player must focus on which of the three boosters they are are igniting, where they are pointing the rocket as a result, whether they are going off course, flying into a comet's path, or running out of time before the mission fails. Better players will snag power-ups that extend the clock or allow the rocket to be upgraded. Best players will arrange the longest possible paths of pipe, which, for some reason, cause the rocket to get the biggest boost.

Stellar Art Design: There are two wonderful things to look at in Link 'N Launch. First is the upgradable rocketship which looks so much like something Captian Olimar from Pikmin games would fly that I've decided this game is a stealth Pikmin spin-off. Upgrading one's rocketship via collected power-ups provides both a boost in the ship's flight performance but a wonderful punchy transformation of dumpy vessel into sleeker ship, each upgrade creating a more fantastic and fun craft. What looked like a flying potato is now a mighty carrot, of sorts. The other visual stand-out is the fuel that flows through the pipe paths the player arranges. Once a path links fuel source to one or more of the rocket's three boosters a pink goo flows through the pipes. That probably seems like nothing special when described here, but it offers the same satisfaction that Yosemite Sam appeared to have in those old Bugs Bunny cartoons when he got to watch the fuse he lit travel a winding path of gunpowder toward the barrel in which he was sure Bugs was hiding. I hope, though, that you can plan your paths better than Sam usually did.

Hated
The Game's Terrible Name: Typed out, Link 'N Launch looks like the name of a Zelda game that shouldn't exist. Maybe Launch is Link's 'lil pal! The two guys hang out when Link is not rescuing Princess Zelda and this game is about their fun adventures? Or maybe the person who doesn't get that bad impression merely hears me saying the name of the game to them. Do they think I just said Lincoln Launch? Are they wondering if this game is about one of America's great presidents doing something or other? Worse, maybe they actually hear the correct words: Link 'N Launch. And, unless they've been dying to link things and then launch things, I bet they're hoping I change the topic. The name of this game is a liability for anyone who wants to, with good reason, make the game sound like something interesting and worth trying. In a downloadable games market where a game's name may be its only selling point, having a bad one is unfortunate.

Link 'N Launch, despite its name, is impressive. At first, the game seems like just another twist on the same genre that was used for the pipe-connecting hacking system in the original Bioshock. But just 10 minutes with the game already reveals that there is a design thickness here of a layered and captivating puzzle game. This is a puzzle game in which how you play the board you're on has much to do with whether you have a decent chance to do well on the next one. And while it suffers some from the problem of the original Lumines, that it can sometimes take too long to get tough enough for players who've played it regularly for a week, it's novel for a long enough time to earn a recommendation.

There's a depth and cleverness in Link 'N Launch that is rare among the smallish games offered for download on portable devices these days. This is true for several of the Nintendo-published DSiWare games. Based on that trend, perhaps some of the best Japanese game makers, those whom seem more spiritually tied to the simpler times of simpler hardware and more tightly-crafted game design, can establish a lead role in the development of tightly-made, downloadable games. I just hope that they try to name them better.

Link 'N Launch was developed by Intelligent Systems and published by Nintendo as a download-only game for the Nintendo DSi on February 8. Retails for $5.00 USD. I cleared the game's 10 increasingly-challenging and lengthy fly-toward-the-planet missions, finished a dozen of the 100 standalone bonus puzzle challenges, unlocked one extra mode and heard the game's single piece of music again and again and again. I think I'm still hearing it now.

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In the past weeks, there have been two TRF articles about Erik Verlinde's alternative interpretation of gravity as an entropic force:

Gravity as a holographic entropic force
Erik Verlinde clarifies some issues

At the beginning, I thought that Erik meant something sophisticated that could work - a new dual (yet universal) way of looking at the gravitational phenomena.

But right now, after the helpful explanations by Erik, I am afraid that I am certain that he shares certain basic misconceptions about physics with the advocates of spin foams, loop quantum gravities, causal dynamical triangulations, octopi swimming in the spin foam, condensed matter gravities, and many other stupid things of the same kind. So in this sense, he shouldn't be quite surprised that these people are trying to build on his paper as a new context to repeat their old incoherent flapdoodle.

I will try to summarize the reasons why nothing like that can ever work because Nature disagrees with the very basic pillars of this system of ideas - and all systems that share certain general assumptions.

But let me begin with a specific new criticism directed against Erik's picture. Let's look at an ordinary double-slit experiment with a massive particle such as an electron or a neutron. The neutrons will turn out to be the best ones.



Everyone knows the double-slit experiment, so I have immediately added the unusual ingredient due to Erik Verlinde. In his preprint, he argues that the entropy of two gravitationally bound objects depends on the distance between them.

In particular, he argues in equation (3.6) and above it that if a probe (small point mass) is shifted by Δx away from the holographic screen (and therefore closer to the center of a gravitational field), the entropy changes by Δx/L where L is the Compton wavelength of the small massive particle. To avoid infinities, let's consider neutrons whose Compton wavelength is 10^{-15} meters or so.

So if you move such a neutron 1 meter closer to (or further from? Who cares...) the holographic screen, there will be a higher number of microstates available to you. For each microstate at one position, there will be exp(10^{15})) states where the neutron is at the other position. These entropy differences may be so huge because Erik assumes that they're being taken from the maximum entropy carried by the holographic screen - which resembles the entropy of an equally sized black hole. The latter is the maximum entropy you can squeeze in a given volume and it is proportional to the area in the Planck units.

Now, the distance (height difference) between the two slits doesn't have to be quite one meter. But it may be substantially longer than the neutron Compton wavelength which means that the ratio between the number of states will be more than astronomical.

Clearly, a neutron going through the two slits can only interfere with itself if the microstates are sharply defined, don't decohere from one another, don't mix up with many other states, are not measured, and so on. There's no doubt that a discrepancy between the number of states corresponding to the upper slit and the lower slit would destroy the interference pattern.

But the interference is known to exist, even in the gravitational field. That much is known even for the electrons. This proves that for each position "x" of the interfering particle, regardless of the position of "x" in the gravitational fields, there must exist exactly one state that describes the situation. That's necessary for the "one-particle" Schrödinger's equation to work even in the gravitational fields. So even electrons instantly falsify Erik's philosophy because in the reality, the interference pattern is not destroyed. However, the picture is even more manifest and constraining in the case of neutrons.

In 1975, Colella, Overhauser, and Werner did the first experiment that tested the effect of a gravitational field (of Earth) on interference; their paper had many follow-ups and boasts 339 citations at this moment.

Using a neutron interferometer (which is dozens of centimeters in size), they exactly found the result that the equivalence principle predicts: the interference pattern is just "freely" falling in the gravitational field, just like the classical neutrons would. The equivalence principle works even when it comes to the quantum phenomena such as interference. Gravity and its equivalence principle work not only when many chaotic things and phenomena cancel: it works even when a single elementary particle is falling down.

The pattern is not destroyed in any way and the phases are shifted exactly as you would think if you thought properly. It's been experimentally verified that Schrödinger's equation including the gravitational potential energy works. Later, it became possible to verify not only the uniform gravitational field but even the tidal forces - the non-uniformities of the gravitational field. Everything works properly. You can see such tidal forces in the interference pattern.

The idea that the number of microstates - the exponential of the entropy - depends on the position of the elementary particles has thus been safely ruled out.

The different branches of the wave function couldn't interfere with each other if there had been no one-to-one map between the states at different altitudes of the neutron or if there were some thermalization going on before the neutron reaches the photographic plate. In our discussions, Erik (and Wilke) defended a very fast thermalization (in order to keep the system at equilibrium at all times) which only makes the things related to interference worse because the interference pattern dies even faster.

Recall that I have argued that Erik's dynamical picture is fundamentally irreversible, unlike gravity.

At the end, Erik (and Wilke) agreed that there is some inherent irreversibility that can't be eliminated but they blamed it on the gravitational waves which I think is indefensible. While I am certain that the gravitational waves emitted by a binary states are essentially pure, calculable, coherent states (exponentials of a graviton creation operator) with a negligible entropy, the definition of irreversibility and the constraints coming from it may look confusing to others which is why I chose the simple interference pattern in this article which should not be confusing.

The idea that there is any "chaos" hiding behind the fundamental forces such as gravity is fundamentally wrong for many other reasons. These reasons are morally equivalent to the argument above but they address different traditions and flawed alternative theories from the history of physics.

The most important one among them was the...

Luminiferous aether.

In the 19th century, physicists wanted to "model" the electromagnetic field as a mechanical system with many wheels and gears: at the end, they even produced a working prototype. ;-)

It was a completely irrational movement with no scientific justification. But many physicists, including a few giants, have simply found mechanics (which was already old) more natural than field theory (which was new, and it was originally meant to approximate many-body mechanics), so they badly wanted such a picture. It's often hard for the people to understand that a newer conceptual picture may be fundamental. (But it always can - there's nothing wrong with being newer. What matters is whether the principle is right.) That's why some people wanted to reduce field theory to mechanics 150 years ago and why some of our contemporaries want to reduce quantum mechanics to a deterministic theory, among other examples of ill-motivated, misguided physics.

Einstein's 1905 relativity revolution can be summarized as a successful assassination attempt against the aether. Einstein appreciated that the Galilean principle of relativity must morally hold not only for the mechanical phenomena but also for the electromagnetic ones. One shouldn't be able to determine whether her train is moving, not even by using optics. After all, Maxwell's equations do seem to imply that the speed of light is always "c" - and they don't even expect us to specify a frame.

Years before relativity, Lorentz actually managed to prove that Maxwell's equations were Lorentz-invariant but he couldn't possibly understand that the transformations ("changes of variables") formed a group (which we call the Lorentz group today - because there's no way to avoid this irony) or that it had anything to do with the Galilean choices of the inertial frames. Einstein was necessary for these advances that may look trivial today.

Maxwell's equations therefore have to hold in all inertial frames, too. That, bizarrely, implied that the speed of light was constant in all frames: it isn't changed to "v+c" or "v-c". Once Einstein convinced himself that this additional postulate had to be valid and something basic about the space and time would have to be altered, nothing could already have stopped him from finding the correct new theory of space, time, and their relationship, the special theory of relativity. It simply followed from the postulates.

Einstein often acknowledged another important role played by Lorentz who wrote down the right explanation of the electromagnetic phenomena in various materials. Lorentz realized that there is only one fundamental electric (E) and one fundamental magnetic (B) vector at each point of space and time. The vectors D,H were derived by mixing E,B with the information about the charge and spin carriers in the material. This made the vacuum much "emptier" and Einstein could ultimately "empty it" completely: he removed the rest of the aether and showed that it couldn't exist because it would be inconsistent with relativity.

The aether is inconsistent with relativity because of many related reasons. Pretty much all of them also belong among the diseases of all the "emergent" theories of space, time, and gravity that have been proposed in literature.

If your spacetime history resembles anything like a spinfoam, it's easy to see that it can only look isotropic in at most one reference frame. If one frame makes it look isotropic, it is easy to apply the Lorentz transformations to see that the "spin network" - a slice of the spin foam - will be Lorentz-contracted in other frames.

There are many other, equally obvious ways to see that there can't be any aether in the vacuum. If the material filling the vacuum were resembling water, it would carry a nonzero entropy. But relativity instructs us to study not only the entropy density - a scalar field - but also the entropy current, a vectorial field that combines with the scalar entropy density into a 4-vector field in spacetime. These things transform into each other in the same way as different components of the j^{\mu}, the electric current written in a relativistic fashion. In this case, the integrals over codimension-one slices are not interpreted as the total charge (which is quantized and conserved) but as the total entropy on the slice (which is not quantized, it's approximate, and increases). But the Lorentz properties are identical.

It's very clear that if the vacuum had a nonzero entropy density, there would only exist one privileged reference frame in which the spatial components of the entropy current would be equal to zero. Relativity says that the Lorentz invariance can't be broken by the vacuum. It follows that the vacuum can't have any entropy density.

A similar argument applied to the stress-energy tensor implies that only stress-energy tensors proportional to the metric tensor are allowed in the vacuum. Indeed, string theory agrees with these consistency conditions: the vacuum is unique and the energy density is always combined with the pressure of the same magnitude and the opposite sign. Every semi-realistic, stabilized stringy vacuum has either flat, or de Sitter, or anti de Sitter solutions.

While the precise value of the cosmological constant is not calculable at this moment - or, at least, we don't know how to choose the right one among many discrete options - string theory does imply that the vacuum fluctuations behave like the cosmological constant, i.e. satisfy "p = -rho". The latter condition - the equation of state of the dark energy - is not only a moral consequence of relativity but has also been directly tested by WMAP. It works.

Theories that don't respect the exact Lorentz invariance induce a nonzero entropy density which confirms the Lorentz breaking. They also lead to independent components of the stress-energy tensor, "p" and "rho", in the vacuum. It follows that they inevitably suffer from one new cosmological constant problem because they not only lack the explanation for why "rho" is so small, but also an explanation why "p" is equal to "-rho" and is therefore equally tiny. ;-) (Of course, they also generate infinitely many additional wrong coefficients for all interactions etc., but that's another issue.)

Holography leads us to imagine that the microstates of any system can be embedded into the quantum bits of a holographic screen that resembles a black hole horizon. However, any viable interpretation must be able to explain that the vacuum is a unique state and there are unique states for any position of the neutron in the gravitational field, and so on. String theory in general and the AdS/CFT correspondence in particular satisfy these constraints while Erik's framework does not.

It seems a pretty general temptation of some physicists to be struggling for an explanation of Nature that is crowded with chaotic phenomena that introduce a lot of mess into physics. For reasons that are completely misguided, they think that these are good things if not cool.

But the fundamental laws of Nature have exactly the opposite property. They're as ordered and organized as you can get. The equivalence principle, the postulates of quantum mechanics (the interpretation of the probability amplitudes and linearity of the operators), unitarity (the preservation of the information), the Lorentz symmetry (locally), and other similarly key principles uniformly work, and all of their combinations demonstrably work, too (even though it took some time to get convinced that there's really no contradiction).

The interference experiments yield immensely sharp results that agree with the theories amazingly well. Frequencies (and even the magnetic moment of the electron) can be measured stunningly accurately and everything works. There's just no room for any chaos here. Whoever is looking for chaotic explanations is looking for theories that are dead at birth.

So the difficult goal is not to explain why there's so much chaos or increasing entropy or violations of the principles above or previously unknown collapses of the wave function or [add almost any other kind of fashionable crap you like] behind the fundamental forces but, on the contrary, why there is none of it in Nature. People who are trying to deny the principles from the previous paragraph and invent classically chaotic "visualizations" of the fundamental forces may call themselves independent thinkers or whatever, but that won't change the fact that they misunderstand some very basic insights about all of physics.

In this case, I won't be blaming the postmodern developments of the 21st century for this deformation and recurring attempts to explain the spacetime or gravity in similarly flawed ways. There is a simple reason why I won't: the aether goes back to the 19th century if not much longer than that. Together with the attempts to "unexplain" quantum mechanics by a silly deterministic picture, these flawed "alternative attempts" are likely to stay with us for quite some time.