EmDrive study officially published - <AUTHOR> http://arc.aiaa.org/doi/full/10.2514/1.B36120 <comment><USER2> Recent previous discussion:

[https://news.ycombinator.com/item?id=12992536](https://news.ycombinator.com/item?id=12992536)

<comment><USER3> Since there's obvious appetite to discuss this, we've merged the comments here instead of burying the current (re)post as a dupe like we normally would.

A couple more posts about this:

[https://news.ycombinator.com/item?id=12994541](https://news.ycombinator.com/item?id=12994541)

[https://news.ycombinator.com/item?id=12994400](https://news.ycombinator.com/item?id=12994400)

</comment></comment><comment><USER4> This is pretty good news if only that we will get more research into this phenomenon.

In 1933 von Neumann basically published a proof against the idea of any hidden-variable theory. It took 30 years but Bell then discredited it.

My guess is that a lot of this will get revisited. The outcome of this in the next 10-20 years might be really cheap probes (via reusable launch vehicles like SpaceX is making) that need no propellent to continue onto their merry way for a long time. The current way of doing this would be using solar sails or something along those lines which is not exactly compact.

Having a way to push your little probe along (even at a little bit of acceleration) without having to carry a lot of heavy propellant is a big deal. Maybe just some solar panels to generate the energy needed.

<comment><USER5> > This is pretty good news if only that we will get more research into this > phenomenon.

Or maybe it's just a waste of time/money? (I'm not being facetious for the sake of it. See cjensen's comment[1])

[1] [https://news.ycombinator.com/item?id=12995341](https://news.ycombinator.com/item?id=12995341)

<comment><USER6> Nothing in that comment is news, but if we've reached a point where we're _completely_ unwilling to accept that experiments could show us something new before theorists predict and explain it, then we should hang up our science hats and go home.

Skepticism is warranted, but the team behind this study seems to be proceeding with a healthy dose of it, and AFAIK they have not made any inappropriate claims. The results so far are interesting, the experiments do not seem terribly expensive, and I see no reason why they shouldn't be followed to their conclusion (which will probably be the discovery of a mundane explanation for the phenomenon that's been observed).

<comment><USER7> Are you actually worried that all of the world's scientists are completely unimaginative and incompetent? I don't understand why you'd escalate it this way just because _this_ topic comes up. That certainly doesn't sound like a reliable frame of mind in which to be.

<comment><USER6> You seem to be looking at my comment through a radically different lens than I was when I wrote it. You know it was in reply to another comment, right?

</comment></comment></comment></comment></comment><comment><USER8> It's so frustrating. One micronewton per kilowatt. All that power going in, and so little force coming out. All it takes is some tiny noise effect to get that much force. The effect is so weak and they're so near the noise threshold.

Quotes: "Components get warmer and the geometry changes slightly due to thermal expansion". "The thermal signal in the vacuum runs was slightly larger than the magnitude of the impulsive signal." "As the aluminum heat sink got warmer, its thermal expansion dominated the shifting center of gravity (CG) of the test article mounted on the torsion pendulum. This CG shift caused the balanced neutral point baseline of the torsion pendulum to shift with the same polarity as the impulsive signal when the test article was mounted in the forward or reverse thrust direction." "The seventh error is outgassing, which has the potential for a false positive from vaporization of surface molecules of the dielectric insert or other nonmetallic surfaces."

<comment><USER9> > It's so frustrating. One micronewton per kilowatt. All that power going in, > and so little force coming out. All it takes is some tiny noise effect to > get that much force. The effect is so weak and they're so near the noise > threshold.

Yep. Reminds me of psi. You can set up mechanical radiation-decay powered RNGs with pre-set runs of numbers in pre-registered double-blind experiments with remote audit logs analyzed carefully with permutation tests and randomness test suites, and all of the huge effects claimed by regular people and psychics go away... but you still get on net a _slight_ excess of bit flips in the psi direction. Is psi real? Seems highly unlikely. But what could possibly be left - publication bias, fraud, or what? No one knows. At some point, effects become subtle enough that you just can't believe studies finding it on net - there's some sort of epistemological 'noise threshold' where stuff is happening but you don't know why or can come up with causal explanations.

<comment><USER10> > you still get on net a slight excess of bit flips in the psi direction.

Is that "net" extracted from all published experiments, i.e. in some meta syntheses? And is statistically significance calculated in each individual experiment?

> Is psi real? Seems highly unlikely. But what could possibly be left - > publication bias, fraud, or what? No one knows.

Publication bias toward positive results should be detectable via methods such as funnel plots.

If you've looked into these aspects it would make interesting reading.

<comment><USER9> > Is that "net" extracted from all published experiments, i.e. in some meta > syntheses? And is statistically significance calculated in each individual > experiment?

You can find excesses in both individual experiments and meta-analyses, IIRC.

> Publication bias toward positive results should be detectable via methods > such as funnel plots.

Funnel plots have notoriously low statistical power, it would require only a little publication bias to produce excesses, and asymmetry in a funnel plot can be due to other reasons.

<comment><USER10> Thanks for these comments, will make for interesting investigations.

</comment></comment></comment></comment></comment><comment><USER11> There seems to be a meme around the EmDrive where "it works" and "conservation of momentum is upheld" are mutually exclusive. Couldn't it be the case that there is some local phenomenon happening that we do not understand that still manages to maintain conservation of momentum? Isn't assuming that momentum conservation is violated a conjecture on the underlying physics of the device, which we don't know?

<comment><USER12> It's a little more complicated than conservation of momentum, which is just a subset of conservation of energy useful for intuition about the non quantum world. If you're converting energy into massive particles or photons for propulsion you can still have a "massless" drive while maintaining conservation of momentum because what you're really conserving is the total energy of the system. Research has previously shown that it is possible to create particles but it requires ungodly amounts of energy and a specially designed apparatus that separates the resulting particle and antiparticle using quantum effects before they can annihilate each other. There is even some research into using a vibrating "quantum mirror" that forces virtual photons to become real using only energy from quantum fluctuations but that's even more complicated and difficult to engineer.

Either the EM drive has a unique combination of features that allows efficient creation and separation of particles using electricity, some other unknown quantum effects are present that can convert energy to momentum without an opposite reaction on another particle/field, or there is still a hidden error. Given the scientific knowledge we have today, it's extremely likely to be the latter but that doesn't preclude the possibility that we have discovered something novel.

<comment><USER13> Really annoying to see false expertise pop up again and again.

> conservation of momentum, which is just a subset of conservation of energy

This is false. Momentum and energy are two different things, even with mass- energy equivalence. In particular, momentum is a vector while energy is a scalar, and their mass-energy equivalent units (impulse vs energy) are also different.

Also: pair production doesn't necessarily require some amazing quantum device to keep the pair separate.

> There is even some research into using a vibrating "quantum mirror" that > forces virtual photons to become real using only energy from quantum > fluctuations but that's even more complicated and difficult to engineer.

This is true if you consider conservation of energy to be an engineering problem. Under no scientific theory can you pluck energy from the vacuum.

<comment><USER14> _> Momentum and energy are two different things, even with mass-energy equivalence. In particular, momentum is a vector while energy is a scalar, and their mass-energy equivalent units (impulse vs energy) are also different._

None of this is correct when you take relativity into account. In relativity, momentum and energy are both parts of a 4-vector, and that 4-vector is conserved. And in natural units, in which c = 1, energy and momentum have the same units. Particle physicists use these units all the time.

<comment><USER13> Yes, I know how the 4-dimensional momentum vector in relativity works.

I'm not aware of a physical view for which energy and momentum are the same for the purposes of something like the EmDrive. In particular, you cannot completely turn one into the other by a choice of coordinates, and you cannot mix them by any physical process. And I could be wrong, but I'm 99% sure you need both energy and momentum conservation to get 4-momentum conservation.

No matter your view, conserving the spacelike components of 4-momentum is not "a subset of the conservation of energy". And the truth/falsehood of this view has nothing to do with the "non quantum world". Relativity was an extension of classical electrodynamics before it was anything else.

<comment><USER12> _> And I could be wrong, but I'm 99% sure you need both energy and momentum conservation to get 4-momentum conservation._

I'm almost certain you're wrong. The most mathematically precise definition I remember for conservation of 4-momentum only requires that the interaction is invariant to spacetime translations. I don't see how that requires you to conserve both separately from the whole.

 _> No matter your view, conserving the spacelike components of 4-momentum is not "a subset of the conservation of energy". And the truth/falsehood of this view has nothing to do with the "non quantum world". Relativity was an extension of classical electrodynamics before it was anything else._

That was a poor choice of words on my part. I meant that an understanding of conservation of momentum based in classical mechanics is rather meaningless when talking about a drive that might use energy to create particles. What matters is that the total energy of the system is conserved and I stand by my choice of "subset" because momentum is _not independently conserved._ Calling conservation of momentum a subset of conservation of energy is not even close to calling energy the same thing as momentum and I have absolutely no clue where you got that idea.

<comment><USER13> There's a confusion here which you still don't get. Momentum is not 4-momentum. Conservation of latter implies the former but the reverse is not necessarily true. And nothing in the above is a "subset of conservation of energy"\--that's absurd.

Actually, I'm not 99% sure, I'm 100% sure. It's very easy to imagine a relativistic system where momentum is conserved but energy isn't. Imagine if the universe was made of inelastic billiard balls, with no internal "heat", so every collision just lost energy. But momentum is still conserved.

<comment><USER14> _> It's very easy to imagine a relativistic system where momentum is conserved but energy isn't. Imagine if the universe was made of inelastic billiard balls, with no internal "heat", so every collision just lost energy._

This won't work. Let's suppose we have just two billiard balls, and that 3-momentum is conserved in the center of mass frame (in which it is by definition zero), but energy in this frame decreases at each collision. (Ignore the fact that this obviously implies that the 4-momentum of the system is not conserved, even though it is undergoing no external interactions.) Now transform into any other inertial frame. You will find that 3-momentum is not conserved either; it has a different nonzero value after a collision than before.

<comment><USER13> This is a bizarre comment. If we forget about energy, this is equivalent to saying 3-momentum is not conserved in inelastic collisions _in real life_. Which is false.

<comment><USER14> _> this is equivalent to saying 3-momentum is not conserved in inelastic collisions in real life._

No, it's not. In real life, energy is conserved, so the energy that is lost from kinetic energy in inelastic collisions needs to go somewhere. And whatever receives that energy will also have momentum (even if it doesn't in the center of mass frame, it will in other frames), so it has to be included in the accounting of momentum conservation as well as energy conservation. A relativistic theory that conserves energy as well as 3-momentum (i.e., standard relativity theory) will still conserve both energy and 3-momentum when you change frames, even in inelastic collisions. (In the simplest case, the lost kinetic energy goes into increasing the rest mass of the two billiard balls, by increasing their temperature.)

What you hypothesized was something different: a hypothetical relativistic theory (which obviously does not match our actual world) in which energy is not conserved but 3-momentum is. In such a hypothetical theory, inelastic collisions could take place without the lost kinetic energy going anywhere: it simply disappears. I am simply explaining why such a relativistic theory is not possible: if energy is not conserved, 3-momentum cannot be conserved either (except in one particular frame, the center of mass frame, but that violates the principle of relativity so it is not allowed in a relativistic theory).

<comment><USER13> No, the 4-momentum is conserved _as a vector_ given a reference frame, which means all 4 parts are conserved, which means 3-momentum is conserved. It doesn't "go somewhere".

You seem to be obsessed about conservation of the magnitude of 4-momentum under Lorentz transformations. It's the whole vector I'm talking about, not the magnitude. and change-of-frame is not a necessary part of conservation laws.

The claim that you can observe conversation in one frame but not another is absurd. The laws are affine; they hold in any frame or none.

<comment><USER14> _> the 4-momentum is conserved_

In standard relativity, yes. But not in your hypothetical "relativistic system where momentum is conserved but energy isn't". You said such a system was easy to imagine. I simply pointed out that, easy to imagine or not, such a system doesn't work. Nothing that I said about 3-momentum being conserved in one frame but not another applies to standard relativity where the 4-momentum is conserved. It only applies to the hypothetical system that you claimed was easy to imagine. I don't understand why you keep talking as though my comments about 3-momentum being conserved in one frame but not another referred to standard relativity.

 _> It doesn't "go somewhere"._

By "go somewhere" I simply meant energy can get transferred from one part of the system to another. I didn't mean that total energy wasn't conserved (in standard relativity).

 _> change-of-frame is not a necessary part of conservation laws._

It is in a relativistic theory, since the principle of relativity requires that the laws of physics, including conservation laws, must hold in all frames.

 _> The claim that you can observe conversation in one frame but not another is absurd._

For standard relativity, of course it is. But not for your hypothetical system.

 _> The laws are affine; they hold in any frame or none._

This seems to contradict what you said earlier in the same post, that "change of frame is not a necessary part of conservation laws".

<comment><USER13> You seem confused by how conservation works, and intent on misunderstanding it.

All I can say is that momentum conservation is Lorentz invariant in my system, and hence cannot depend on choice of reference frame. The conserved quantity is not invariant, and conserved quantities do not need to be Lorentz invariant, and fact almost always are not. If this confuses you, sorry, but I cannot follow your reasoning anymore.

<comment><USER14> _> All I can say is that momentum conservation is Lorentz invariant in my system_

If by "my system" you mean your hypothetical theory where energy is not conserved but 3-momentum is, I strongly suspect you have not done the math. See below.

 _> The conserved quantity is not invariant, and conserved quantities do not need to buslye Lorentz invariant, and fact almost always are not. If this confuses you, sorry, but I cannot follow your reasoning anymore._

I understand what you are saying here, but it does not refute what I was saying. You are saying that, for example, in standard relativity, energy is conserved--in a given frame, it stays the same through any series of events-- but it is not frame invariant; changing frames changes the energy. I agree with that.

What I am saying is something different: in your hypothetical relativistic theory in which energy is not conserved, then 3-momentum cannot be conserved in any frame other than one particular one (which in my example was the center of mass frame). I am not saying the numerical value of the 3-momentum has to be the same in all frames. I am saying that in all frames but one, the numerical value of the 3-momentum, as evaluated in that frame, is different after an inelastic collision than before, i.e., 3-momentum is not conserved in that frame.

Here is the math backing up that assertion. Suppose 3-momentum is conserved in the center of mass frame. In that frame the 3-momentum is zero. We assume that our system consists of just two billiard balls, each with the same rest mass m. Before the collision, one ball has speed v and the other has speed -v (we can restrict ourselves to one spatial direction). After the collision, one ball has speed w and the other has speed -w, where w < v (because the collision is inelastic). So 3-momentum is zero before and after the collision in this frame, and energy is not conserved--it is smaller after the collision.

Now transform to any other frame. Call the relative velocity of the Lorentz transformation u. Then, in this frame, the speeds of the two balls before the collision are (I am using units where c = 1)

v+' = (u + v)/(1 + uv)

v-' = (u - v)/(1 - uv)

and the speeds after the collision are

w+' = (u + w)/(1 + uw)

w-' = (u - w)/(1 - uw)

Now we evaluate the 3-momentum in this frame. Before the collision, it is

m ( v+'/sqrt(1 - (v+')^2) + v-'/sqrt(1 - (v-')^2) )

After the collision, it is

m ( w+'/sqrt(1 - (w+')^2) + w-'/sqrt(1 - (w-')^2) )

Substituting and straightforward algebra simplifies these to

before = 2mu/sqrt[(1-u^2)(1-v^2)]

after = 2mu/sqrt[(1-u^2)(1-w^2)]

These are obviously not equal, hence 3-momentum is not conserved in this frame. (In standard relativity, where energy is conserved, 3-momentum would be conserved as well; as I mentioned before, the simplest way for that to happen would be for the two billiard balls to heat up, increasing their rest mass. More complicated ways would involve other particles, or the billiard balls emitting radiation, or something like that.)

<comment><USER14> Just to clean up one item: I did assume in the above that the rest mass of the billiard balls was unchanged in the inelastic collision. But we can drop that assumption and still prove that, if energy is not conserved in the center of mass frame, 3-momentum cannot be conserved in any frame other than the center of mass frame. Suppose the rest mass of the balls after the collision is M (instead of m). Then we have for the 3-momentum before (P0') and after (P1') the collision, in a frame with velocity u relative to the center of mass frame:

P0' = 2mu/sqrt[(1-u^2)(1-v^2)]

P1' = 2Mu/sqrt[(1-u^2)(1-w^2)]

But we can simplify this by writing down the total energy before (E0) and after (E1) the collision, in the center of mass frame:

E0 = 2m/sqrt(1-v^2)

E1 = 2M/sqrt(1-w^2)

So we can see that

P0' = E0 (u/sqrt(1-u^2))

P1' = E1 (u/sqrt(1-u^2))

Hence, if E0 > E1, we must also have P0' > P1. In other words, the only reason we happen to have P0 = P1 in the center of mass frame is that being in that frame is equivalent to having u = 0 in the above formulas.

(It is also straightforward to show that if energy is not conserved in the center of mass frame, it is not conserved in any frame. So the Lorentz invariance of the two conservation laws, energy and momentum, cannot be separated--they are inseparably linked.)

</comment></comment></comment></comment></comment></comment></comment></comment></comment></comment></comment></comment></comment></comment></comment><comment><USER15> Interesting what are the fundamental reasons for the thrust. It's certainly not throwing photons. Hypotheses:

* Flawed study. It actually throws something (like, cavity material slowly ablating) or repels of Eddy currents in surroundings;

* It repels of Earth (and the force has either gravitational or magnetic nature); then it's not suitable for deep space propulsion

* A sort of ether actually exists, and it throws that. Though, then there would be some anisotropy showing ether wind; in this case it is suitable to be used in deep space

<comment><USER16> If you read through their conclusions, they suggest that there may be a quantum vacuum capable of transmitting oscillations and this vacuum is what this this device pushes off of leaving a wake behind.

<comment><USER17> [Disclaimer: I think it's a measurement error.]

Just ignore the theoretical explanations. Just imagine that it's something they wrote to avoid the crackpot tag. That explanation doesn't make any sense. Also avoid all the other theoretical explanations, they are also very sloppy.

Just concentrate in the experiments, that is the less sloppy part of these reports.

If they discovered something new, then they can make a working prototype and improve it until it's clear that they are measuring something really new and it's not an experimental error or a misattributed force. They can make foolproof instructions so anyone can make a version in a good enough lab and reproduce the experiment, or sell an experimental setup in Ebay. Then it will "confirmed".

There has been a many famous experiments that were later debunked, like:

* cold fussion [https://en.wikipedia.org/wiki/Cold_fusion](https://en.wikipedia.org/wiki/Cold_fusion) , they had also some kind of theoretical excuse, but it was wrong and it was impossible to reproduce the experiment.

* arsenic in DNA [https://en.wikipedia.org/wiki/GFAJ-1](https://en.wikipedia.org/wiki/GFAJ-1) , they had also some kind of theoretical excuse, but it was wrong and it was impossible to reproduce the experiment.

If you want success cases, my favorites are:

* the asymmetric disintegration of cobalt in a magnetic field [https://en.wikipedia.org/wiki/Wu_experiment](https://en.wikipedia.org/wiki/Wu_experiment) , I guess they had some wrong explanation, but the correct explanation was discovered like 20 years later

* high temperature superconductivity [https://en.wikipedia.org/wiki/High-temperature_superconducti...](https://en.wikipedia.org/wiki/High-temperature_superconductivity) IIRC they have some explanation or practical rules, but the correct explanation was discovered like 20 years later

Just concentrate in the experiments, and wait 20 years for a good explanation.

<comment><USER18> > They can make foolproof instructions so anyone can make a version in a good > enough lab and reproduce the experiment,

Is that not what this is? Roger Shawyer invented it, but NASA, NWPU and the Dresden University of Technology have all built and verified their own versions to work.

<comment><USER19> The TU Dresden people did not "verify" that the device works --- instead, they identified many spurious error sources, and recognized that the final results were essentially null on the level of measurement accuracy, and unable to say whether there's thrust or not.

[http://arc.aiaa.org/doi/pdf/10.2514/6.2015-4083](http://arc.aiaa.org/doi/pdf/10.2514/6.2015-4083) [https://tu-dresden.de/ing/maschinenwesen/ilr/rfs/ressourcen/...](https://tu- dresden.de/ing/maschinenwesen/ilr/rfs/ressourcen/dateien/forschung/folder-2007-08-21-5231434330/ag_raumfahrtantriebe/JPC ---Direct-Thrust-Measurements-of-an-EM-Drive-and-Evaluation-of-Possible-Side- Effects.pdf?lang=en)

<comment><USER18> Oops, you're right. Thanks for the correction!

</comment></comment></comment></comment></comment></comment><comment><USER20> There is an elaborate analysis of potential error sources, which I appreciate highly. However, I would have preferred a more rigorous quantitative analysis.

The offered explanation model is highly fascinating. I'd appreciate if somebody would chime in with a more understandable version or resources thereto.

</comment><comment><USER6> A while back I read an interesting but possibly also batshit crazy article that proposed an explanation possibly involving something like quantization of inertia, and/or generation of extremely long-wavelength photons, wavelengths on the order of the size of the universe.

Does anyone know what I'm talking about? IIRC it was based on some theoretical work that was done before EmDrive was a thing, and it seemed less hand-wavey to me than simply "conservation of momentum is wrong" or "we're using the quantum vacuum as a tractive medium which is supposed to be impossible but whatever" explanations.

I'm not saying this explanation is right (or wrong, or that the thrust observed in these experiments is or isn't caused by "new physics"); I'm just curious whether anyone knows what I'm talking about and can provide some more context.

edit, found it: [https://www.technologyreview.com/s/601299/the-curious- link-b...](https://www.technologyreview.com/s/601299/the-curious-link-between- the-fly-by-anomaly-and-the-impossible-emdrive-thruster/)

Any thoughts?

<comment><USER21> I think you're talking about McCulloch's quantisation of inertia theory. [http://www.ptep-online.com/index_files/2015/PP-40-15.PDF](http://www.ptep- online.com/index_files/2015/PP-40-15.PDF) which I believe was originally inspired by the rotation of galaxies.

<comment><USER6> Yup, that's it. I found the article I read, edited my post to include it.

</comment></comment></comment><comment><USER22> If anyone's lazy, I highly suggest at least reading parts 9 and 10. One of the interesting takeaways here is that Q __* -thrust is 2 orders of magnitude stronger than Photon-thrusters, and about 1-2 orders of magnitude lower than Ion-thrusters.

 __* A Q-thruster is a thruster which pushes off of the zero point fluctuations in vacuum, which is still not understood.

<comment><USER23> But if you will try to discuss pilot-wave and walking droplets here (they are mentioned in part 10), you will receive lot of downvotes here.

Quote:

Although the idea of a pilot wave or realist interpretation of quantum mechanics is not the dominant view of physics today (which favors the Copenhagen interpretation), it has seen a strong resurgence of interest over the last decade based on some experimental work pioneered by Couder and Fort [13]. Couder and Fort discovered that bouncing a millimeter-sized droplet on a vibrating shallow fluid bath at just the right resonance frequency created a scenario where the bouncing droplet created a wave pattern on the shallow bath that also seemed to guide the droplet along its way. To Couder and Fort, this seemed very similar to the pilot-wave concept just discussed and, in subsequent testing by Couder and others, this macroscopic classical system was able to exhibit characteristics thought to be restricted to the quantum realm. To date, this hydrodynamic pilot-wave analog system has been able to duplicate the double slit experiment findings, tunneling, quantized orbits, and numerous other quantum phenomena. Bush put together two thorough review papers chronicling the experimental work being done in this domain by numerous universities [14,15].

<comment><USER24> > But if you will try to discuss pilot-wave and walking droplets here (they > are mentioned in part 10), you will receive lot of downvotes here.

If you try to claim, without evidence, that pilot waves predict different behavior than standard quantum mechanics, you might deserve that downvote.

Pilot waves are a mathematical framework, they may be useful mathematical tricks in some cases, but they don't predict new behavior AFAIK.

I've been to talks about Couder et al's work, and the authors _don 't_ argue that pilot waves are validated as descriptions of the universe by their work. They do demonstrate a novel macroscopic system that observes the laws of classical mechanics, and under certain circumstances, behavior emerges that is nicely described by the pilot wave equations. This does _not_ mean that pilot waves are somehow a more fundamentally correct description of what's really going on.

<comment><USER25> This is actually incorrect. Pilot wave theory gives a deterministic explanation of phenomenon that the standard model treats as frequentist random events. Only if you assume no knowledge of the underlying hidden variables does the model reduce to the same as the frequentist standard model.

This is exactly analogous to statistical mechanics (e.g. the ideal gas law) arising from classical Newtonian mechanics when you assume no specific knowledge about gas particles (individual positions or velocities), just aggregate mass and energy.

An experiment that "proves" an extension of pilot wave theory might be, e.g., observing that decay rates of radioactive isotopes are affected by being in a quantum corral or something like that. An experiment that shows there is a more fundamental, and influenceable process underlying phenomenon that the standard interpretation treats as frequentist.

For this reason it could be easily argued that theoretical physicists should be spending more time on pilot wave theory since it is this sort of theory from which future advances would come, vs the standard interpretation which puts up a semantic stop sign and says "proceed no further".

<comment><USER24> > This is actually incorrect. Pilot wave theory gives a deterministic > explanation of phenomenon that the standard model treats as frequentist > random events.

That's a remarkably incorrect statement. Let's see:

* The "standard model" is a quantum field theory and has essentially nothing to do with this discussion.

* Standard quantum mechanism says _nothing_ about frequentist vs Bayesian interpretations of anything.

* Standard quantum mechanism is a deterministic theory, too. Take a look at the Schrödinger equation: it's deterministic.

Determinism is tricky. Suppose you have a particle doing its thing (going through double slits or whatever) and then you measure its position. In standard QM, you have two choices: you use the Born rule (or a fancier version -- I like the POVM formalism) and get a distribution of outcomes and a new post-measurement wavefunction, or you can include the measurement apparatus in your system and you end up with many worlds. In PWT, I think you have two similar choices. You can start with a distribution of your (hidden) initial condition and get an resulting distribution over the outcomes (which will be the same as the Born rule distribution if you calculate it correctly). If you do this, you still need to model decoherence, and I believe it looks at least as artificial as the standard QM case. Alternatively, you could presumably add degrees of freedom and more hidden variables to describe the measurement apparatus and you end up with an IMO extremely messy version of many worlds.

<aside>My personal view is that standard QM with many worlds is the best theory we have. If you start with the many worlds hypothesis and assume that it's totally impractical to devise an experiment that actually detects coherence between large-scale states, you can ignore this coherence, average it out, recover the Born rule, etc, as an approximation. IOW I think that decoherence is a limitation of our ability to build crazy experiments rather than a fundamental property of the universe.</aside>

</comment></comment></comment></comment></comment><comment><USER26> [http://blogs.discovermagazine.com/outthere/2014/08/06/nasa-v...](http://blogs.discovermagazine.com/outthere/2014/08/06/nasa- validate-imposible-space-drive-word/)

About the previous tests of the same team:

"The testing was done by five NASA employees in a lab devoted to exploring unorthodox propulsion ideas. The team leader is a researcher named Harold "Sonny" White, himself a proponent of ideas about faster-than-light warp drives that most of his colleagues have classified as physically impossible. The lead author is one of White's Eagleworks teammates, David A. Brady. Calling this group "NASA"—as almost every popular news story has done—is a gross oversimplification."

<comment><USER27> They fund it, no?

<comment><USER26> Would it be better if NASA wouldn't have less then 10 people, out of their 18,000 employees (0.05%), working on testing nevertheless such claims which almost surely don't work?

Maybe, if that 0.05% is used against NASA by claiming it doesn't do its job how it should.

<comment><USER28> Interestingly, NASA used to have a group working on such projects.

[https://en.wikipedia.org/wiki/Breakthrough_Propulsion_Physic...](https://en.wikipedia.org/wiki/Breakthrough_Propulsion_Physics_Program)

And I believe they actually did a serious job, which is probably why they never found any warp-drive ;-)

</comment></comment></comment></comment><comment><USER29> If you pressurize a sealed cavity with a gas, it's not going to move due to the internal pressure regardless of what shape you make it. If you sum all of the collisions of the gas atoms along with the container, the sum momentum will be zero. Momentum is mass x velocity.

Contrast this with pressure created via light. Velocities with light don't add that way. Instead there is a red/blue shift in the frequency.

I can't put my finger on how this could work, but it seems there is a discontinuity here between the speed of light being constant in all reference frames and summing velocities to calculate momentum.

Maybe with light, only energy conservation matters and momentum can be changed via redshift/blueshift relative to the container.

<comment><USER23> You know that everything around us is both matter and wave at same time (wave- particle duality). Right? I.e. small bit of matter surrounded with wave. (See any of walking droplets videos to develop intuition).

Unlike regular matter, waves are propagating through space, by contraction and expanding of a field. Because of particle-wave duality, when matter is moving, EM field around matter expands and contracts at high frequency. Right?

EM radiation in form of radio-waves can interact with these surrounding waves because of interference. Right?

IMHO, interference between radio-waves and surrounding waves may cause effect similar to used in acoustic levitation.

<comment><USER23> These anonymous downvotes are frustrating. I cannot guess what caused them, so I cannot learn on my mistakes.

<comment><USER30> I downvoted for basically the same reason as 'danbruc -- the comment contains inaccuracies (as far as I understand physics, IANAP) that don't become accurate just by appending "Right?" to them. I don't really read that "Right?" as condescension like 'humbledrone but more as a verbal tick. I hear it from others and even suffer from it myself sometimes, the idea is that a "Right?" pause offers the other party in the conversation a chance to interrupt and correct you, because you're not entirely certain of your own assertions. But that doesn't work so well in written communication except maybe with instant messaging.

I gave you an upvote for persisting in getting corrections/tips from people like 'danbruc and 'lutusp though. Since you were interested in simulation you might enjoy this article (or others on his site) from an actual physicist: [http://oyhus.no/QuantumMechanicsForProgrammers.html](http://oyhus.no/QuantumMechanicsForProgrammers.html)

<comment><USER23> Can you enumerate these inaccuracies, please?

PS.

I enjoyed articles about [https://en.wikipedia.org/wiki/Amplituhedron](https://en.wikipedia.org/wiki/Amplituhedron) .

</comment></comment></comment></comment></comment><comment><USER2> Any chance this thing is using dark matter as reaction mass? We're confident that dark matter exists because it's the only thing that perfectly explains the evidence from gravitational lensing of colliding galaxies (eg. [https://en.wikipedia.org/wiki/Bullet_Cluster](https://en.wikipedia.org/wiki/Bullet_Cluster) ). Finding a way to interact with dark matter sounds much more plausible than breaking thermodynamics.

<comment><USER31> Please read where the "dark matter" term came from. It's not a faerie dust that facilitates magic use. It's just a hypothetical matter in the universe that we can't observe, because for some yet-unknown reason it doesn't emit light. There's no reason it can't be just regular matter.

<comment><USER32> Not only does it not emit light, it does not interact with electromagnetic waves in any way.

<comment><USER33> And it doesn't obscure light - doesn't leave a shadow. No, its not regular matter at all. Its definitely something strange.

<comment><USER34> If it is something at all and not only a flaw in our theories.

<comment><USER35> Calling it "inexplicable gravity thing that makes galaxies work" does not exude confidence.

</comment></comment></comment></comment></comment></comment><comment><USER36> One thing that bothers me about this paper:

The measurement error is stated to be +/\- 6 micro-Newtons. However, the difference between force measured _at the same power_ is 30-40 micro-Newtons and the "measurement error" is listed as the +/\- error. So if the measurement error is that low then the additional variation is unreliability of the effect itself _or_ a miscalculation of the measurement error.

</comment><comment><USER37> Can someone smarter than I explain the impact of this?

<comment><USER38> It's a machine that seems to produce a miniscule amount of thrust without a propellant. The laws of physics as we know them require that momentum always be conserved, but this thing seems to move without pushing on anything, which should be completely impossible.

Most likely what's happening here is a thermal effect or the machine pushing off the earth's magnetic field. Keep in mind that these things are very difficult to measure due to the tiny amount of thrust they may or may not produce. According to this study 1.2mN was measured, which is about the same amount of force as gravity exerts on 6-7 grains of rice (according to my back- of-the napkin calculation).

If this were real it would be absolutely huge, and destroy just about all of modern physics. It isn't just that we believe in conservation of momentum because we don't know of any way to break it, the equations we're using to describe things don't work without it.

This paper has a number of flaws. For example, the test really needed to be performed inside of a vaccuum to have any credibility at all, and whether that was the case was not made clear.

TL;DR It's most likely bunk, unfortunately, but it would be very revolutionary if true

<comment><USER17> The 6-7 grains of rice is an interesting comparison, but they actually they didn't get 1.2mN, they got 1.2mN/kW and they only tested the device with 40W, 60W and 80W and they got [http://arc.aiaa.org/action/showPopup?citid=citart1&id=t3&doi...](http://arc.aiaa.org/action/showPopup?citid=citart1&id=t3&doi=10.2514%2F1.B36120&area=aop) so they only measure a force of ~70uN, that is like 1/25 of a grain of rice, that's probably like a few grains of salt.

And then they use a "aggressive slope-filtering level" method (whatever it means) to get 124uN, that is still very small, like 1/10 of a grain of rice.

<comment><USER39> The results would be a great deal clearer if they could test it in a high vacuum at 2 to 4 kW. Measuring 3-4 millinewtons reliably is a lot easier to believe than a newton force equivalent to a tiny fraction of 1 grain of rice.

</comment></comment></comment></comment><comment><USER40> How much evidence is needed to motivate testing it in space? It seems that would settle the dispute regarding whether it works or not. Considering how inexpensive cubesats are to launch, it seems like it could be launched for about $100k, not including the additional R&D.

<comment><USER41> I could be mistaken, but I believe someone is lunching such a test next year.

Edit: Cannae Inc. intends to launch a test with a small satellite. 2017 is so far a guess for launch based on a quick search.

</comment></comment><comment><USER28> Several comments have hinted at the possibility that this would be a over- unity device but as I couldn't find a specific demonstration, here is one that does not involve any fancy physics.

Let's assume we have a spacecraft powered by an energy source with total energy `E` and mass `m`. The EM-drive produces a constant thrust `F` at a constant power `P`.

Kinetic energy of the S/C after time `t`:

        Ek = 0.5 * F^2 * t^2 / m

If `t` is the time at which the energy in the source is exhausted, then the ratio of kinetic energy developed to the expended energy (E = t * P) is:

        Ek/E = 0.5 * F^2 / P^2 * (E/m)

So this basically says that we have a over-unity device whenever the energy source has a specific energy above:

        E/m > 2P/F ~ 1.6 10^6 J/kg

which is certainly not achievable in practice, but in theory is totally fine being still well below c^2 (which by the way justifies a-posteriori the neglect of relativistic corrections in the above).

</comment><comment><USER42> Can't we put one in a cube sat and give it a go? (or: why can't we?)

<comment><USER43> I'd think power is a problem. This produces a very slight acceleration with a kilowatt of power, while it looks like a 3U (triple stack) cubesat might produce ~14 watts.

<comment><USER44> Cannae is launching its thruster experiment in a 6U cubesat next year: [http://www.popularmechanics.com/science/energy/a22678/em- dri...](http://www.popularmechanics.com/science/energy/a22678/em-drive-cannae- cubesat-reactionless/).

<comment><USER42> Cool! Any chance a 6U could stay up for month with conventional thrusters? Or will it be proven to work or at least be better than other thrusters once and for all?

</comment></comment></comment></comment><comment><USER45> Thanks for submitting this, love to see feedback from the physicists who hang out around here!

<comment><USER46> There was a very elaborate experiment in Germany regarding this.

They concluded that the force is excerted by coupling the RF-energy from the outside.

If the system is fully self-contained (driven by a battery physically connected to the cavity) there is no thrust to be measured.

It's very sad to see NASA being involved in such shitty research.

<comment><USER47> The linked paper draws no such conclusion:

"The nature of the signals observed is still unclear."

They are, clearly, taking the tack of eliminating all sources of measurement error. But they haven't yet achieved that, and as yet a force remains. It seems perfectly reasonable to assume it _will_ be attributed to measurement error, but that is not yet the case:

" Next steps include better magnetic shielding.... We believe that this is a good education project to track down measurement errors..."

<comment><USER46> Yes, and the is the point.

NASA would have had the means to eliminate most of those sources of errors. I wouldn't call these measurement errors though -> the measurement is fine - your setup is the source of error.

But they decided not to follow such a line of research.

And yes, they are right "We believe that this is a good education project to track down measurement errors".

The measurement error being the "thrust" that is due to your experimental setup.

But let them waste some more money, time and reputation and build this in space so they can find out it does not actually work.

<comment><USER48> Did you create this account only to comment on this story? (just curious)

> NASA would have had the means to eliminate most of those sources of errors.

Yes. NASA as a whole yes. One group researching something that may or may not bear fruit no.

So it's natural they try to eliminate easier errors first. But (as an example) it's one thing to have a good vacuum, another one to have an _excellent_ vacuum for testing. So first you test on the good vacuum.

<comment><USER46> > Did you create this account only to comment on this story? (just curious)

Yes i did, usually i just let certain topics pass by me and never comment here.

RF-cavities though are the very core to my line of research, so my acceptance for bs is very low in this regard.

If one wants to convince me of a thrust effect: build a prototype where the power source (a battery for example) and the RF-source are strapped onto the cavity, put the whole setup in a vacuum of your choice (i heard NASA has very nice and !large! facilities) and show me a sustained increase in impulse (just let it rotate for a while)

<comment><USER49> > If one wants to convince me of a thrust effect: build a prototype where the > power source (a battery for example) and the RF-source are strapped onto the > cavity, put the whole setup in a vacuum of your choice (i heard NASA has > very nice and !large! facilities) and show me a sustained increase in > impulse (just let it rotate for a while)

Okay, but they aren't trying to convince _you_ yet.

They're trying to convince _themselves_ that it's worth spending the resources you describe.

<comment><USER50> Excellent point. They do mention performing an experiment with large angular displacement and a larger vacuum.

> To definitively rule out any residual concerns about thermal error sources, > future test campaigns could employ a test apparatus capable of measuring > small torques over much larger angular displacements. For example, a > Cavendish balance approach properly designed to allow very large rotation > angles such as 90, 180, or even 360 deg will not be susceptible to this type > of thermal false positive.

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER51> > Although this test campaign was not focused on optimizing performance and > was more an exercise in existence proof, it is still useful to put the > observed thrust-to-power figure of 1.2mN/kW1.2 mN/kW in context. The current > state-of–the-art thrust to power for a Hall thruster is on the order of > 60mN/kW60 mN/kW. This is an order of magnitude higher than the test article > evaluated during the course of this vacuum campaign; however, for missions > with very large delta-v requirements, having a propellant consumption rate > of zero could offset the higher power requirements. The 1.2mN/kW1.2 mN/kW > performance parameter is over two orders of magnitude higher than other > forms of "zero-propellant" propulsion, such as light sails, laser > propulsion, and photon rockets having thrust-to-power levels in the > 3.33–6.67μN/kW3.33–6.67 μN/kW (or 0.0033–0.0067mN/kW0.0033–0.0067 mN/kW) > range.

Read More: [http://arc.aiaa.org/doi/full/10.2514/1.B36120#_i36](http://arc.aiaa.org/doi/full/10.2514/1.B36120#_i36)

</comment><comment><USER52> _If the vacuum is indeed mutable and degradable as was explored, then it might be possible to do /extract work on/from the vacuum, and thereby be possible to push off of the quantum vacuum and preserve the laws of conservation of energy and conservation of momentum. It is proposed that the tapered RF test article pushes off of quantum vacuum fluctuations, and the thruster generates a volumetric body force and moves in one direction while a wake is established in the quantum vacuum that moves in the other direction._

...well, at least it's better than calculating the theoretical produced thrust by ignoring the axial component of the radiation pressure against the side walls. Which is how tapered resonant cavities like this were supposed to produce thrust when I was in high school.

But, leaving a wake in the vacuum should require that the vacuum exists in some particular reference frame. How's that supposed to work?

Or since the paragraphs immediately before that one discussed the vacuum behaving differently when there's stuff in it, are they just saying that _something_ is being exhausted out the back (which should be visible by some sort of effect on the vacuum?) even if they have no idea what that something might be?

</comment><comment><USER53> Open Source Projects / Experiments that might be relevant to the discussion:

[https://hackaday.io/project/5596-em- drive](https://hackaday.io/project/5596-em-drive) [https://hackaday.io/project/10166-flying-an- emdrive](https://hackaday.io/project/10166-flying-an-emdrive)

</comment><comment><USER54> For the uninitiated how good or bad is 1.2mN/kw?

<comment><USER55> To put into proportions: The radio isotope thermoelectric generator (RTG) of the Voyager spacecraft wheighs 37kg. So let's say we can build a spacecraft using this and the EM drive weighing a total of 50kg. The RTG produces 157W of power. This translates to a change in speed 30cm per day.

Bonus question: The power of the RTG halfes avery 87.7 years. What is the asymptotic speed the spacecraft will reach?

<comment><USER56> Asking this is like asking how long it should take for a sperm cell to swim across the Atlantic Ocean.

The EMD is simply not applicable to scales where RTGs are used, much as a 5MW maritime diesel turbine is not applicable to swimming motions of a biological cell. The power density of Voyager is a hundred times lower than what an EMD ship would need.

</comment></comment></comment><comment><USER57> Doesn't a standard microwave (or any other) transmitter produce a tiny force due to radiation pressure?

I understand that this is different because the radiation bounces around an enclosed chamber and so momentum wouldn't be conserved, but if the issue is to create propellant-free propulsion, doesn't that already exist (even though it's not practical)?

<comment><USER58> > Doesn't a standard microwave (or any other) transmitter produce a tiny force > due to radiation pressure?

pressure against what?

<comment><USER57> [https://en.wikipedia.org/wiki/Radiation_pressure#Radiation_p...](https://en.wikipedia.org/wiki/Radiation_pressure#Radiation_pressure_by_emission)

<comment><USER58> this article includes a grey body that the force is acting upon.

the difference with the EM drive's method of propulsion is, that while the article you posted describes a force reacting upon an external, "grey body," as is acceptable with the copenhagen interpretation of quantum mechanics, the EM drive force exhibits a characteristic betrayed by a theoretical pilot wave, which indicates a non-copenhagen interpretation of quantum mechanics, but rather a bohmann version of quantum mechanics, in which the force can act upon itself.

run-on sentence alert.

</comment></comment></comment></comment><comment><USER59> Goddamit, I wanted to get to the comment about the superoptimizer, not this mass hallucination over crap sience :(

</comment><comment><USER60> Some criticism on reddit:

[https://www.reddit.com/r/science/comments/5dqy9b/em_drive_is...](https://www.reddit.com/r/science/comments/5dqy9b/em_drive_is_shown_to_work_measurement_of/da6n92f/)

</comment><comment><USER61> For those who dig this stuff...I strongly recommend you watch BBC Horizon episode Project greenglow

[http://www.dailymotion.com/video/x40a65t](http://www.dailymotion.com/video/x40a65t)

</comment><comment><USER39> 1.2 millinewtons per kW is not a lot - the size of a 12kW solar array for a large satellite is quite considerable... Space based nuclear reactors anyone? No cosmos-954 incidents, hopefully.

</comment><comment><USER62> For those who wish to see the abstract page without enabling cookies. [http://archive.is/zuVaz](http://archive.is/zuVaz)

</comment><comment><USER63> If this holds up I am prepared to believe in almost anything – like the universe being a simulation and this is a deterministic round-off error.

Conservation of momentum is pretty fundamental.

</comment><comment><USER64> I don't understand how the 1.2mN/kW is better than the hall thruster that achieves 60mN/kW ? Isn't it better to achieve higher mN per kW than lower?

<comment><USER65> Every other thruster works by pushing something small at very high speeds in the opposite direction of the direction you wish to move in. Hall thrusters are pushing small ions at near the speed of light or something, right?

This thruster pushes nothing. It just achieves thrust with only energy. No refueling ever, solar/nuclear energy into movement until you have no more energy.

This violates certain physical laws, but there it is being measured anyways.

<comment><USER66> Hall-effect thrusters throw ions at 15 to 30 Km/s, or 0.0001c.

There is one other thruster that doesn't need a tank of reaction mass: a photon rocket-- moving yourself around only using radiation pressure. Exhaust speed really is c, but generated thrust is tiny, since photons are pretty light. The resonant cavity thruster is more interesting than a photon rocket, since its thrust is much higher.

</comment></comment></comment><comment><USER67> The laws of physics prevailed, despite the LHC and other experiments. As awesome as it sounds, I find it hard to believe that this finding is something relevant.

</comment><comment><USER68> For those new to this, the emdrive is very likely bogus.

1\. It violates Conservation of Momentum. If the phenomena is real, a large number of basic Physics principles would need to be discarded.

2\. It was designed based on certain principles. Those principles have been shown to be wrong. But it works anyway because _reasons_?

3\. The results of each experiment are suspiciously close to the limits of measurement.

There are two choices here: (a) experimental error or (b) profound alteration to fundamental physics. Occam's Razor applies. Also, "extraordinary claims require extraordinary evidence" and this evidence is far from extraordinary.

That this is being published in a journal which does not cover basic physics is not helping.

<comment><USER69> Agree with everything you write except,

> That this is being published in a journal which does not cover basic physics > is not helping

AIAA is an extremely reputable journal and society. All the members are extremely familiar with conservation of momentum.

The observation of superluminal photons (later disproved) was published in reputable journals as well.

No scientist took either result very seriously. However, the observation of anomalous results is a result worth of publication and communication to other scientists and engineers.

As a practicing scientist, I can assure you that peer-review does not mean something is 'correct', but that is it not provably false, and that the results may be important to the community.

<comment><USER70> The hope is that this gives the idea some legitimacy, which will encourage others to test the idea too. It's like a win-win situation, if you test it and you discredit the effect, that's a free paper. If you verify it or add your own little spin, you'll go down in the history books along with this team.

</comment></comment></comment><comment><USER71> So 1.2 mN/kW. By comparison the ion engine on the Dawn probe puts out 34 mN/kW (236mN / 6.9 kW). But of course that's for an effectively infinite exhaust velocity rather than just 42 km/s.

</comment><comment><USER72> When the super-conducting version work it will change the world.

</comment><comment><USER73> If real, you could build a perpetual motion machine with it. Therefore it's not real.

<comment><USER74> Could you? How? Perpetual motion machines must put out at least as much energy as they take in. AIUI the EmDrive requires external power (such as solar panels) and produces a rather tiny amount of force. This does not sound to me like it's anywhere even remotely close to putting out as much energy as it takes in.

<comment><USER75> It's because there's no such thing as absolute velocity, so your thrust can't vary with velocity, it has to be a constant for given input energy. Kinetic energy is the square of velocity, so as you keep accelerating at a constant rate, you'll eventually get to some velocity at which the energy you get out is higher than the energy you put in, assuming your reactionless drive is more efficient than a photon rocket.

Not that it matters. If it works, it already violates conservation of momentum as we currently understand it. That's just as fundamental as conservation of energy.

<comment><USER76> Hmm, relativistic velocity under constant acceleration is

        v(t) = a t / sqrt(1 + a^2 t^2)

and relativistic kinetic energy is

        Ek = m c^2 / sqrt(1 - v^2/c^2) - m c^2

Leave out the constant -mc^ and for simplicity put m=1, v=1, c=1, and we get

        Ek = (1 - t^2/(1+t^2))^(-1/2)

which is linear in larger values of t, not square.

Proof:

        d/dt Ek = t sqrt(1 / (1 + t^2))
                = sqrt(t^2 / (1 + t^2))

which is always < 1.

<comment><USER75> So at the extreme efficiencies Shawyer claimed, overunity was at decidedly nonrelativistic velocity. It'd be interesting to calculate a maximum drive efficiency before you get overunity.

I've seen claims that the max is the efficiency of a photon rocket, but I haven't seen it backed up with math.

</comment></comment></comment></comment></comment><comment><USER77> Sounds like Polywater:

[https://en.wikipedia.org/wiki/Polywater](https://en.wikipedia.org/wiki/Polywater)

</comment><comment><USER78> As I said earlier this is bogus. We might as well try to prove virgin birth.

<comment><USER56> [https://en.wikipedia.org/wiki/Parthenogenesis](https://en.wikipedia.org/wiki/Parthenogenesis)

</comment></comment><comment><USER79> I was pretty sure there was a seperate study where they debunct it? Gonna look for the link...

</comment><comment><USER80> SPR's Roger Shawyer Explaining The Basic Science behind #EmDrive:

[https://www.youtube.com/watch?v=wBtk6xWDrwY](https://www.youtube.com/watch?v=wBtk6xWDrwY)

<comment><USER81> Since many people may be jumping into this topic without context/awareness: Shawyer's explanations simply do not hold up. Even the minority of folks that know physics and think the emdrive is real agree that Shawyer's proposals are invalid. Further, he's been at this for years, repeatedly making grandiose claims and failing to deliver on them. Take anything he says with a huge grain of salt.</comment></comment>


Ad hoc data analysis/discovery on event data with Clojure and Spark - <AUTHOR> http://danoyoung.blogspot.com/2015/10/and-bobs-your-uncle.html <comment><USER2> I've run similar analyses on advertising data with Spark/Scala. This is what I would consider the 'easy' part: identifying whether or not a user, in the context of some 'session' (or specific ad campaign) saw ads (and which/how many) for that campaign before completing a conversion. Though I used cogroup and reduce to get to this, as conversions are in a separate dataset.

The hard part is building a model which discovers, at each frequency level (or sets of various n number of events), the weights/value of each ad in the campaign (or all campaigns for a given advertiser) in driving conversions for optimization. Really fun stuff to work on, but at the moment it's at a low priority level :(</comment>


Has TechCrunch jumped the shark? They're profiling a website that sells videos of fireplace logs (yes, really) - <AUTHOR> http://www.techcrunch.com/2007/11/26/iyuletv-a-yule-log-for-your-iphone/

<comment><USER2> I think you can make the case he jumped the shark long ago:

[http://cache.valleywag.com/assets/resources/2006/08/satire-i...](http://cache.valleywag.com/assets/resources/2006/08/satire- is-dead.jpg)

</comment><comment><USER3> i loved that episode!

<comment><USER4> <http://www.youtube.com/watch?v=MpraJYnbVtE></comment></comment>


Ask HN: What is your daily reading list? - <AUTHOR> Besides HN can you list one website that you go to the moment you get connected. <comment><USER3> I'm a politics junkie/anorak for Australia/UK as well as multiple other countries and polities.

I have been completely dissatisfied with the precipitous decline, as well as pay-walling, of broadsheets over the last decade and a half that I've been a regular reader. They simply can't do serious coverage because adverts demand they do lowest common denominator reporting. Also I want more than one side to a story and basically all papers, whether they like to declare it or not, have a position and so I end up at least going to two broadsheets to settle my mind on an issue.

Reddit was good for a while but the memes, insults, manipulation of multiple subreddits by racist groups (/r/worldnews, /r/europe) and the bashing down of anything that isn't left-wing on others (again, I want to see all points of view) got me very tired of it.

Twitter is good, but there is so much you can miss, links aren't headlines and I have absolutely zero interest in the meme-like jocularity and 'what I had for lunch' postings. Although discovery is fairly good it's entirely subject to the filter bubble effect and people are often ranting to a select group of yes-women and yes-men.

I want clustered news and opinion, and I want it ranked globally not against my own personal filter bubble. As there is nothing out there that fits my reading pattern I have started building <http://jkl.io> . However crowdfunding hasn't worked to get it going beyond a prototype and so it's going to be longer development cycle to add further features like machine learning (plus votes) ranked comments. But hopefully all that will be done by the end of the year as well as different views and ways of getting into the data. That said, it's now at a stage where it's genuinely my first stop before all the others, and once there are more sources, comments and the like, it will be the perfect overview - for me personally, perhaps not for others - <USER2> news/politics/policy/economics/science/tech across the world.

Also: criticism here would be most welcome, my other thread asking for feedback from HN never caught on.

</comment><comment><USER4> I don't have a daily reading list, as I've found that it harms my productivity. I usually let the problem I'm trying to solve drive me to reading and research. Other than having something to talk about at the water cooler, I've found that trying to "stay informed" or "keep abreast of industry trends" are just excuses for not doing real work.

<comment><USER5> Which is why you find yourself here?

<comment><USER4> :)

If you _must_ know, I was glancing over the headlines while eating breakfast, pondering how to get a colleague to stop being so theoretical and actually try putting some of their ideas into action. (A very smart person who, as you may have guessed, reads tons of stuff everyday.)

To mutilate an old saying: In theory, reading about something and doing something are the same thing. In practice, they're not.

(edit: P.S. There was a time when I read everything I could get my hands on. I eventually learned that I much prefer to be effective, not smart.)

</comment></comment></comment><comment><USER6>
      http://consumeconsume.com/
      http://www.reddit.com/r/AskHistorians/
      http://thesocietypages.org/socimages/
      http://www.contemporist.com/
      http://randomghost.tumblr.com/

Contemporist currently showing errors and occasional CloudFlare messages - load issue? It's architecture/interiors/furniture.

If you like futuristic concepts, Random Ghost and its infinite scroll will eat your day. It's amazing.

Consume Consume is an incredible mixture of bizarre, awesome or amusing images. A good, occasional break from the grind.

<comment><USER7> Why is Consume Consume so awesome? Thx

<comment><USER6> Because of our planet and everyone on it.

</comment></comment></comment><comment><USER8> The subreddits I subscribe to:

<http://www.reddit.com/r/javascript/>

<http://www.reddit.com/r/programming>

<http://www.reddit.com/r/worldnews/>

<http://www.reddit.com/r/DepthHub/>

<http://www.reddit.com/r/todayilearned/>

<http://www.reddit.com/r/AskHistorians/>

<http://www.reddit.com/r/IAmA/>

Except for TIL and worldnews, this is a good mix since they all have about the same level of voting and activity.

<comment><USER9> Reddit should compensate voting based on subreddit activity. I only have a few subreddits on my homepage, and for example the Bitcoin one gets entirely overruled by TIL.

</comment></comment><comment><USER10> Reddit, for sure. If you haven't tried it for a while, give it another go. There are some excellent sub-Reddits and just turning off some of the worst default ones can make a big difference to the quality.

<comment><USER11> What subreddits do you recommend?

<comment><USER12> This one is oddly fascinating -

<http://www.reddit.com/r/whatisthisthing/>

There are also these -

<http://www.reddit.com/r/coffee/>

<http://www.reddit.com/r/dataisbeautiful/>

<http://www.reddit.com/r/chemicalreactiongifs/>

There's also /r/startups, but it's plain boring.

<comment><USER13> > This one is oddly fascinating -

><http://www.reddit.com/r/whatisthisthing/>

I love that Reddit. I use it to practice my websearch skills. When I have some knowledge about something I know what words to use, so going to that subreddit gives me a bunch of stuff where I have no knowledge at all, and I need to learn the right words to use.

</comment></comment></comment></comment><comment><USER14> I get as much value from the comments as the stories themselves so:

\- HN (still the king for quality of comments as well as generally interesting links)

\- Reddit (some sub-reddits are very interesting, especially domain specific ones)

\- Stackoverflow sites (some great info here, but their rather draconian rules on questions that require opinions can cause frustrations as many answers do require some sort of opinion. It is quite amazing how often I get value from questions that have been closed as not constructive.)

\- BoingBoing.net (used to be a regular but has become too weird for my tastes)

</comment><comment><USER15> * My email, where I maintain good, legitimate correspondence.

* My RSS reader, where I subscribe to the blogs of friends, plus the Machine Learning Research Institute, Ben Goertzel, and Venkatesh Rao.

* Reddit, where I'm split evenly between smart things and slutty things: [http://www.reddit.com/r/Anarcho_Capitalism+anarchotranshuman...](http://www.reddit.com/r/Anarcho_Capitalism+anarchotranshumanist+Androgynoushotties+Anthropology+artificial+AskAnthropology+AskCultures+AskHistorians+Assistance+Badass_people+BiGoneMild+Bitcoin+booksuggestions+collapse+communism+confession+cooperatives+dataisbeautiful+DeadBedrooms+deCrypto+DepthHub+DMT+dyke+dykesgonemild+EDC+electronic_cigarette+emogirls+Esperanto+Existentialism+ExoLife+explainlikeimfive+Favors+FifthWorldPics+fifthworldproblems+FiftyFifty+Fitness+forhire+Forth+FriendlyAI+GirlsGoneBitcoin+girlskissing+GirlswithNeonHair+HIPSTERGURLZ+homemadexxx+incest+incorrectphilippines+intentionalcommunity+IWantOut+IWantOutJobs+jobbit+jobpostings+Jobs4Bitcoins+JournalingIsArt+linguistics+littlespace+Loans+LucidDreaming+malefashionadvice+MapPorn+MDMA+neurophilosophy+nihilism+Nomad+Nootropics+okc4okc+OkCupid+p4p+passionx+Persians+Pescetarian+Philippines+polyamory+polygonemild+PostCollapse+ProsePorn+Pyongyang+r4r+Random_Acts_of_Books+Random_Acts_Of_Pizza+resilientcommunities+resumes+ronpaul+RoomPorn+SceneGirls+Scholar+seasteading+self+sex+shorthairedhotties+singularity+Stoicism+SuicideWatch+Survival+Swingers+Tagalog+Thetruthishere+TinyTits+tldr+Waif+wikipedia) )

</comment><comment><USER16> I don't really visit websites as such. I use Google Reader as my jumping off point for 75% of what I read online. I hope that once Reader goes dark that I'll find something that fills the void well enough for the transition not to be too harsh.

The rest of my reading is done here and in the accompanying comment threads, of course, and also NeoGAF, a video game forum that (I only realized this week) I've been frequenting for well over a decade.

<comment><USER17> I switched to Feedly from Google Reader, and have more or less adjusted to it.

Its main problem is that it demands you use their browser extension, which makes it far less convenient than Google Reader.

<comment><USER16> Is the extension at least stable? I seem to have terrible luck with extensions and also seem to run into memory leaks or other issues so I tend to avoid them lately.

</comment></comment></comment><comment><USER17> For news I like bbc.co.uk/news and france24.com

I have quite a few rss feeds that I read in the morning

Webcomics : gunshowcomic.com dilbert.com smbc-comics.com nedroid.com whompcomic.com <http://invisiblebread.com/>

<http://lawandthemultiverse.com/> is an interesting blog giving a legal perspective on comics and science-fiction.

Some web/design blogs : <http://speckyboy.com> <http://smashingmagazine.com> <http://css-tricks.com>

Hardware : <http://anandtech.com> <http://bit-tech.net> <http://hardware- canucks.com> <http://youtube.com/linustechtips> <http://youtube.com/timetolivecustoms> <http://toolsandtoys.net>

</comment><comment><USER18> A few people have mentioned Reddits, and some of them really are great. For those who use RSS, you can subscribe to your front page. <https://ssl.reddit.com/prefs/feeds/>

Similarly, if you want a feed of some specific subreddits, you can use something like reddit.com/r/programming+entrepeneur/.rss

</comment><comment><USER19> HackerNews and LessWrong. I go to Reddit only when I'm looking for something particular or when I'm procrastinating heavily.

</comment><comment><USER20> Rather than having a daily list, I use Feeder (Chrome extension: <http://feeder.co/>) to read my RSS feeds, I had always preferred it to Google Reader, I never did get myself into the mantra of checking Reader often (it ended up being once every few months, when I randomly remembered) ; however Feeder is nice in its minimalistic approach, just showing me how many items for each feed, which encourages me to zero it out, although unlike Reader it just shows the titles of RSS feed items, so I end up judging whether or not to read an article based on the title.

A few feeds I follow:

 _News_

* Hacker News - <https://news.ycombinator.com/> (<https://news.ycombinator.com/rss> and <https://news.ycombinator.com/bigrss> [a lot of the posts are repeated over both, and note these are not necessarily the front page posts, my guess is that they are upvoted new posts, so I end up reading some posts before they reach the front page])

* Phoronix - <http://www.phoronix.com/> (<http://www.phoronix.com/rss.php>)

* ThreatPost - <http://threatpost.com/> (<http://threatpost.com/feed>)

* TheNextWeb - <http://thenextweb.com/> (<http://feeds2.feedburner.com/thenextweb>)

* Wired - <http://www.wired.com/> (<http://feeds.wired.com/wired/index>)

* iClarified - <http://www.iclarified.com/> (<http://iclarified.com/rss/rss.xml>)

* TorrentFreak - <https://torrentfreak.com/> (<http://feeds.feedburner.com/Torrentfreak>)

* r/WorldNews - <http://www.reddit.com/r/worldnews> (<http://www.reddit.com/r/worldnews/.rss>)

 _Blogs_

* Securelist - <https://www.securelist.com/> (<https://www.securelist.com/en/rss/allupdates>)

* Buffer Blog - <http://blog.bufferapp.com/> (<http://blog.bufferapp.com/feed/>)

* Raptitude - <http://www.raptitude.com/> (<http://www.raptitude.com/feed/>)

* Priceonomics Blog - <http://blog.priceonomics.com/> (<http://blog.priceonomics.com/rss>)

* Schneier on Security - <http://www.schneier.com/blog/> (<http://www.schneier.com/blog/atom.xml>)

* Daring Fireball - <http://daringfireball.net/> (<http://daringfireball.net/index.xml>)

* xkcd blag - <http://blag.xkcd.com/> (<http://blog.xkcd.com/feed/>)

* Nota Bene (Eugene Kaspersky's blog) \- <http://eugene.kaspersky.com/> (<http://eugene.kaspersky.com/feed/>)

* Troy Hunt's Blog - <http://www.troyhunt.com/> (<http://www.troyhunt.com/feeds/posts/default?alt=rss>)

 _Various_

* xkcd - <http://xkcd.com/> (<http://xkcd.com/rss.xml>)

* What If? - <http://what-if.xkcd.com/> (<http://what-if.xkcd.com/feed.atom>)

* OzBargain - <https://www.ozbargain.com.au/> (<https://www.ozbargain.com.au/feed>)

* Bret Victor's website - <http://worrydream.com/> (<http://worrydream.com/feed.xml>)

<comment><USER9> You don't really read this _every day_ , do you? If so, how much time do you spend on it per day?

<comment><USER21> Do you use an RSS reader? If a site doesn't update in a day, its impact on you is 0. By feedreader standards, that would be a fairly small list.

I've got about 40 feeds in mine, most of the fairly quiet. It doesn't take that long at all.

</comment></comment></comment><comment><USER22> Randy Pausch said in his time management lecture (a good companion to "The Last Lecture") that your criterion for office reading material should be "Will I lose my job if I don't read this?" <http://www.cs.virginia.edu/~robins/Randy/>

<comment><USER23> I don't think that's good advice and leads to some very short term thinking.

Reading only the stuff that you must in order to not get fired is tantamount to doing to bare minimum. Having a sciolistic knowledge about many topics is helpful when coming up with new ideas (and more importantly, knowing where to look when you need to do a deep dive), as well as making you a well-rounded person.

</comment></comment><comment><USER24> Articles:

<http://www.reddit.com/r/programming>

<http://www.altdevblogaday.com/>

<http://www.genbetadev.com/> (Spanish)

<http://android-developers.blogspot.com>

Webcomics:

<http://xkcd.com/> (Monday, Wednesday & Friday)

<http://explosm.net/comics/new>

<http://mountsaintawesome.com/index.php>

<http://abstrusegoose.com/>

Above all, obviously, Hacker News. I spend even more time than all others summed up.

</comment><comment><USER25> Well since the question asked for _one_ website, I'd say Google News. It gets me quickly caught up with what's what in the world.

OTOH, for a longer read with topics I'm interested in, I hit Zite on my iPad or on my Android phone. I've got Zite configured with my favorite subjects, and now I'm fairly comfortable that I'm hitting 80-90% of the most interesting articles/goings-on without having to hit dozens of feeds or sites.

</comment><comment><USER26> <http://www.reddit.com/r/worldnews/> and <http://www.reddit.com/r/Bitcoin/>

i use this chrome extension to easily check for new content: <http://feeder.co/>

</comment><comment><USER9> Hackernews, security.stackexchange.com, the Dutch security.nl and Google+.

Also Reddit and Twitter now and then (I don't follow a while lot of people, so I can read back the whole week in a matter of minutes).

Once a month or so I read xkcd.com and exocomics.com, usually when I'm utterly bored or in a bad mood.

</comment><comment><USER13> Thomson Reuters Foundation - (<http://www.trust.org/?show=alertnethumanitarian>)

UN Office for the Coordination of Humanitarian Affairs -(<http://www.irinnews.org/>)

</comment><comment><USER27> Whenever I need a break from tech:

<http://www.lewrockwell.com>

<comment><USER27> Also, my reddit preferences

<http://www.reddit.com/r/austrian_economics/>

<http://www.reddit.com/r/Anarcho_Capitalism/>

<http://www.reddit.com/r/voluntarism/>

<http://www.reddit.com/r/MarketAnarchism/>

<http://www.reddit.com/r/Libertarian/>

<http://www.reddit.com/r/philosophy/>

</comment></comment><comment><USER28> 600 headlines, 60 tech feeds - <http://skimfeed.com>

<comment><USER29> I gave it a try and the first thing I noticed on the top of Popular category "Memes: How Many Can You Name?". So no, thanks.

</comment></comment><comment><USER30> Some of the stackexchange websites

<http://stackoverflow.com/>

<http://programmers.stackexchange.com/>

<http://answers.onstartups.com/>

</comment><comment><USER31> I'm really surprised that no one has mentioned <http://www.launch.co> \- @jason's news ticker.

Switching to just that has been the most productive thing for my time, and still feel comfortable I'm not missing any relevant news.

</comment><comment><USER32> Ruby Daily - <http://rubydaily.org> \- for instant news about ruby and webdev. Stackoverflow - <http://stackoverflow.com/> \- for dev questions and answers.

</comment><comment><USER33> <http://hubski.com>

<http://popurls.com>

<http://www.brainpickings.org/>

<http://kottke.org>

<comment><USER34> Thanks for the popurls plug

</comment></comment><comment><USER35> I prefer using Flipboard to skim through my Twitter feed + some channels like Gaming, Robert Scoble, Wired (and Hacker News Comments).

Edit: and - of course - whenever I find something interesting, I stop skimming and start reading :)

</comment><comment><USER36> Collection of High-Quality Feeds: <http://talll.com> for tech and <http://filll.com> for finance.

</comment><comment><USER37> I recommend <http://blog.cwa.me.uk/> for new web stuff (somewhat .NET oriented)

</comment><comment><USER38> For business, marketing, and growth-related topics, I use <http://quibb.com>

</comment><comment><USER39> From November to April - <http://www.winterhighland.info/>

</comment><comment><USER40> <http://stern.de> for catching up with normal news.

</comment><comment><USER41> Facebook and Hacker News. My friends post a lot of intriguing articles.

</comment><comment><USER42> <http://techdiem.com/>

</comment><comment><USER43> In order: Feedly, Reddit, and Quora.

</comment><comment><USER44> Finnbay - www.finnbay.com

</comment><comment><USER45> phys.org singularityhub.com fastcompany.com

</comment><comment><USER46> lots of Heinlein and Azimov

</comment><comment><USER47> Techmeme

FT

Business Insider

Reddit

<comment><USER9> FT?

<comment><USER48> Financial Times - <http://www.ft.com/>

</comment></comment></comment><comment><USER49> slashdot.org

</comment><comment><USER50> jezebel.com

</comment><comment><USER51> Slashdot: <http://slashdot.org>, and I have been for over 10 years.

<comment><USER52> I read Slashdot for many years however Hacker News has replaced it for me now. The quality of discussion has become very poor over there plus the stories are often a few days old before they hit the frontpage.

<comment><USER53> I think the summaries are the thing that make me stay on /., especially as HN has strict no-editorializing title policy. I've many times missed an interesting story on HN, then read it from /. and came back to HN for comments.</comment></comment></comment>


Post-Mortem of a Tokyo-based Web Start-up - <AUTHOR> http://www.yongfook.com/2007/07/21/jonkenpon-is-dead/

<comment><AUTHOR> Pull quote:

"The reason we built these apps was, in retrospect, incredibly shallow, and I thank my ex-boss for helping me realise this. We built them because we thought they were going to be popular, following the typical web 2.0 path to riches:

       1. Make popular app.
       2. ???
       3. Profit!!1

"Looking back, I think to myself, is trying to make a popular app enough anymore? If you just attempt to make a popular app, how are you any different from the next web startup. The only thing that separates you is ability, and ability can be hired or learned - so the question becomes who has deeper pockets or more free time. Thusly any idiot with time or money can build a web app these days and these were crowded markets we were attempting to break into - productivity and mobile blogging. What then, separates the wheat from the chaff in this case? For me, I think the big one is emotional investment."

<comment><USER2> to quote vallywag: "Shhh, you're harshing our buzz."

</comment></comment><comment><USER3> Interesting comments from everyone. A couple I would like to address.

"god damn, that guy has a lot of pictures of himself in that article"

Yes, yes I do. Read my blog and you'll discover that I'm a _total_ narcissist. It's all part of the blog theme.

"Is this really true, when you take into account startups that fight tooth and nail and still don't succeed? Is it better to start with the confidence, money, and connections of other people and then ride the wave of their support, or is it better to start with nothing other than your own belief in yourself and then fight tooth and nail until you get the confidence, money, and connections of others?"

Good point. My point then is that you need all of the above. If you have connections, capital and a good idea - then sorry, you're a carbon copy of thousands of other tech entrepreneurs. What separates you from them? Anyone can always get more capital if you poke around a bit. Anyone can get more connections if you spend more time schmoozing. What you can't simply "get" is an emotional attachment to whatever you are doing. That's something that has to be there from the beginning, I think. That is what I learned from this experience.

"Problem 1: trying to build 3 apps while doing consulting work (no focus)"

Definitely. I absolutely agree. However, we were in no position to argue (much) and as I said in the post, the relationship we had with the supposed investor was flawed.

"Problem 2: the author was a dick to his only employee (wtf? why?)"

Ken wasn't an employee. He was being paid the same as me and provided similar functions, although I naturally took on more of a leadership role, being the more experienced. I'm a dick anyway, but yes, I was hard on Ken because I expected him to help me as much as possible not to fuck up the opportunity I thought we had. But when you are ready to launch and you find that there are lots of basic errors in the HTML or front end code because advice you've given over and over hasn't been taken in, it's hard to remain cool and collected, especially if it's with a mate.

If anything, being in that situation taught me that I am not fit to be a boss and not fit to team lead. I am much better working alone, and my individual work speaks for itself. That is why I am now leaning towards solo consulting as the focus of my career.

<comment><AUTHOR> Why'd you pull the article? Did Ken complain?

</comment></comment><comment><USER4> It wasn't even a startup at all. They were lying to themselves that it was. In effect they were employees of an investment firm in some sort of ill-defined incubation weirdness. Everyone involved was pretty clueless about what was going on and what to expect. The investment firm was rolling the dice and these guys were enjoying the learning experience and break from consulting.

<comment><USER5> Most "start ups" run by expats in Japan work this way due to visa issues.

</comment></comment><comment><USER6> A bunch of quotes in this article stuck out at me, but this one in particular:

"How can you possibly have the emotional investment necessary to see things through to profitability, through highs, lows and everything in between, if you haven't fought tooth and nail to get there?"

Is this really true, when you take into account startups that fight tooth and nail and _still_ don't succeed? Is it better to start with the confidence, money, and connections of other people and then ride the wave of their support, or is it better to start with _nothing_ other than your own belief in yourself and then fight tooth and nail until you get the confidence, money, and connections of others?

My boss is trying to convince me that I should at least have an offer of cash in hand from an angel investor before leaving my day job, even if I choose not to take it. While this is quite self-serving (he doesn't want me to leave), it also sounds pretty rational. I mean, right now I have fairly little validation other than my cofounder's confidence, my desire to use our own product, and my belief that I have the technical chops to get to the point where we can.

The article suggests that it's probably better _not_ to have that external validation, and _definitely_ better not to take the money. Is that character- building, or foolhardy?

<comment><USER4> I think you know what you want to do. You've mentioned your boss in a few posts and it sounds like he's a selfish prick, who doesn't genuinely care about what's good for _you_. Maybe you should stop talking to him...

If you're successful you will say "Wow. I almost listened to him" like you dodged a bullet. if you fail, you'll have a much better chance of success next attempt.

<comment><USER6> "You've mentioned your boss in a few posts and it sounds like he's a selfish prick, who doesn't genuinely care about what's good for you."

I actually don't think that - I think he's generally a decent guy who cares about his employees, but cares about his company more. He's even said something to that effect: part of his advice to me was to make sure I can setup a corporate structure that'll survive the departure of founders or key employees, because things do go wrong, and the company is his dream. Perhaps there's a lesson in there: don't let your identity get so wrapped-up in your company that it becomes only _your_ company, one where other people don't feel like they have a chance to make a difference in it. Come to think of it, I've heard similar things from other (failed) entrepreneurs.

You're right though: I guess I just need to go with my gut. Eh, I'm young, I've got plenty of time for failures before success.

</comment></comment></comment><comment><USER7> It seems like the biggest problem is that entered the financing company without a clear relationship defined, and that lack of definition seems like it created an abysmal working environment. I have to admit I am confused how the two developers are maintaining control over the web applications they developed for the company. Something seems a bit off there (they got paid for developing stuff, and then left taking the stuff with them?).

Bonus: The name of their company is "Paper-Rock-Scissors" in Japanese.

</comment><comment><USER5> Emotional investment is overrated.

The reason this endeavor didn't work is:

1\. foreigners living in Tokyo (I lived in tokyo for a year; hugely distracting, hardly an epicenter of web software innovation)

2\. trying to build 3 apps while doing consulting work (no focus)

3\. the author was a dick to his only employee (wtf? why?)

<comment><USER8> 4\. not much effort spent figuring out what market they were going after or what problem they were solving

<comment><USER9> Maybe, but they were doing something right: one site had 7,000 users after 2 months.

It seems their real problem was impatient investors.

</comment></comment></comment><comment><USER10> I'll pull a qoute that struck me

_"It's going to sound cliched and cheesy, but your apps should be an extension of YOU as a person. You should have an emotional connection to the app that transcends thinking about the mercedes it might fucking earn you one day, so that it will keep you interested and give you the motivation to love, care for and improve it."_

I think there's a PG essay about this somewhere. OTOH I'm bother by the amount of pictures this guy has on his webpage. But I love the way he designs the UI's of his web apps.

</comment><comment><USER11> god damn, that guy has a lot of pictures of himself in that article

</comment><comment><USER12> All criticism of his startup strategy aside, his web apps are beautifully executed. I didn't realize that Jason Fried was the American Yong Fook.

</comment><comment><USER13> The core reason for their failure seem to be lack of team spirit. The author clearly considers Ken as a less competent partner.

</comment><comment><USER14> i liked this, thanks for being so honest</comment>


WePad - <AUTHOR> http://wepad.mobi/en

<comment><USER2> I sometimes wonder if this fad of having a massive gloss mark right across screens will pass. It's like they're trying to say "You can be absolutely sure this will reflect everything so that you can't see _anything_ on the actual screen".

When displayed on websites they just seem to take it to extremes. Half the device is black and half is white? :/

Hardware looks quite sexy.

<comment><USER3> Why is a glossy screen considered a "good thing" in the first place? Is there _any_ situation in which a glossy screen is desirable?

<comment><USER2> If you're in the right lighting conditions, blacks are far blacker, contrast is better IMHO than a matt display. But it's a _very_ contentious issue as far as I know.

<comment><USER4> having had both matte and glossy macbook pros, my own observations seem to confirm this: colors are richer and display is brighter (across the same model) but glossy screens get smudged a LOT, and reflect just about everything

<comment><USER5> That's it. If you (the common person TM) are on a shop and look at two laptops side by side, one with a matte screen and the other with a glossy screen, I'm pretty sure that person will be more pleased with the colors on the glossy one.

The problems only appear when you start using it.

<comment><USER2> The problems only appear when you start using it. <In bad lighting setups>

</comment></comment></comment></comment></comment></comment><comment><USER6> Details:

[http://www.neofonie.de/files/product_specifications_WePad_10...](http://www.neofonie.de/files/product_specifications_WePad_1004014.pdf)

Positives: USB ports, Java, Flash, Android apps, built on Linux, Webcam

Negatives: Less battery life than iPad (6 hours vs 10 hours)

<comment><USER7> Negatives: touchscreen not implemented, months or years away from sale

</comment></comment><comment><USER8> Not too shabby, but a few things concern me:

1\. The air vent. Does this thing get hot? How necessary is the air vent? My iPad is always cool as a cucumber, regardless of what I do on it.

2\. The size seems a bit big. Not only is the screen a tad on the large size (or the German pillow girl a tad on the small size), but it also looks pretty thick. The iPad is right on the edge of being to heavy, I wonder what the weight on this thing is.

3\. How polished is this thing going to be? They have more features, ports, etc, but that also introduces complexity. Apple had three iphones with which to work out ui bugs, hardware problems, and other issues.

I'm excited to see how it's received, and also excited to see the upcoming android based tablets. But I'm not holding my breath.

</comment><comment><USER9> I'm looking forward to the android tablets.

<comment><USER10> A website completely devoted to this:

<http://www.androidtablets.net/>

<comment><USER11> is it your site? it looks nice

</comment></comment></comment><comment><USER12> I think those were USB ports I saw in the back.

</comment><comment><USER13> What so hard about building these kind of devices nowadays? It seems to me that all the components are readily available (there is no technological breakthrough in any of them, excepted maybe the screen), and the size of it should make it easier to pack more features or cheaper ones. Unless it's all about the software.

</comment><comment><USER14> I'd really like a full-size laptop with these exact specs (and a full-size battery.) What really detracts from these things' portability is that they basically have to be plugged in every day. It's even the same with my Droid.

</comment><comment><USER15> Runs Android: Excellent. Runs Flash: Too Bad. A year behind the market leader: trouble Will cost more than iPad: marketplace death

You just can't get away with charging more than Apple's offering unless you're providing some kind of genuine innovation. This is unlikely to offer anything iPad doesn't and even if it did, nobody would be inclined to believe it. That means it has to be cheaper, which shouldn't be so hard with Apple's typical margins.

<comment><USER16> Here in Europe the iPad will cost 499 Euro. So 449 is actually cheaper for us.

</comment></comment><comment><USER17> I'm sure it's going to be well engineered like the iPad [http://cdn1.slashgear.com/wp-content/uploads/2010/03/Joo- Joo...](http://cdn1.slashgear.com/wp-content/uploads/2010/03/Joo-Joo- FCC2-540x370.jpg)

oh wait... that was the Joojoo

<http://s1.guide-images.ifixit.com/igi/dDCyRZBNfZ1FxJbI.large>

</comment><comment><USER18> Does this exist, or is it just a late April Fools' joke? Because it seems awfully quick to come up with a real competitor to the iPad...

<comment><USER19> They were developing before the iPad came out, of course. I saw news about them in March, anyway.

They've been marketing to newspapers in Germany, but with the advent of the iPad it would appear they've seen a larger market. I wish they'd get more specific, though. If they're already on the market this summer in Europe, I'm probably going to pick one up.

<comment><USER20> The specs say in Germany they're going to soft-launch it in July and publicly launch in August this year.

</comment></comment></comment><comment><USER4> more informative: <http://www.youtube.com/watch?v=dO0XHMoylZ4>

<comment><USER21> I know this is an early version, but why would you show people a competitor to the iPad that doesn't include a touch interface? Maybe to show off the USB?

<comment><USER22> It has touch. He shows it a little later in the video. One question though is that it appears that he's doing a lot of the touch with his fingernail, which makes me think that the sensitivity is poor.

<comment><USER21> Agh, shamed. The description said touch was upcoming, so I didn't bother watching the entire video.

I guess they say that because they only seem to have a rough prototype with touch right now — the one they were using looked a lot bulkier and more unpolished than the demo model.

<comment><USER22> I was actually wondering why he was padding around with a mouse to start with too.

I wonder though if it supports multi-touch? I really think that's important for tablet computers these days. The control over the device really is so much better.

</comment></comment></comment></comment></comment><comment><USER23> I'm looking forward to seeing if it actually exists, and if so, the price, which I noticed they haven't announced yet.

<comment><USER24> it's in the specs, starts at 449 with wlan, 16gb

<comment><USER23> So about $600 at current exchange rates.

<comment><USER25> but will be sold subsidized, so the price will be lower

<comment><USER26> Wait who's subsidizing it?

<comment><USER25> Afaik, the are making deals with news organizations.

</comment></comment></comment></comment></comment></comment><comment><USER27> Anybody notice the picture of the woman standing up and holding the device? I think it's the last picture in the roll. Not only does she appear somewhat uncomfortable holding it but she is using a pillow in her right hand while standing to kind of prop up the device. Very strange choice for a product shot.

</comment><comment><USER28> I'm wondering what happens to ChromeOS long term if the future is Andriod for portable internet devices.

<comment><USER29> ChromeOS is for netbooks (direct hardware keyboard input, small screen) while Android is for touch devices (android phones, tablet devices, etc).

They're similar, but for completely different markets.

<comment><USER30> I'd pay for a ChromeOS pad - probably a fair amount. With some UI tweaks and a decent context-sensitive onscreen keyboard a ChromeOS pad would be stellar!

(though I am an oddity and only wanting a pad for internet use and nothing else :))

</comment></comment></comment><comment><USER31> this is great news for me. I have already a couple of android apps that i am starting to port with the ipad with the iphone sdk, but my learn curve with objective-c has not been the best.

</comment><comment><USER16> Does anybody know if the battery will be user replaceable?

</comment><comment><USER32> The best thing is:

At the presentation in germany they used windows mobile as operating system ;)

After 1 weeks they tell'd the truth about :P</comment>


Show HN: Truck.app: an SSH browser with rsync - <AUTHOR> http://bonhardcomputing.com/truck/#2017-12-04 <comment><USER2> A FUSE filesystem for rsync-over-ssh would be cool. I found a non-ssh implementation on GitHub: [https://github.com/zaddach/fuse- rsync](https://github.com/zaddach/fuse-rsync)

It seems straightforward to modify to use ssh.

</comment><comment><USER3> Honest question, why is it why is it 21 Megs? It sounds huge for just a front end.

<comment><AUTHOR> _blushes_ \-- 51 when expanded :)

Okay as it's coming up to Christmas....

19 Megs of Qt

18 Megs of Python

5 Meeggggssss of SSL

3 PyObjC

2 MB compiled rsyncs

and a ..bunch..of..other..crap.</comment></comment>


Filecoin ICO raises $200M in 60 minutes - <AUTHOR> https://www.coindesk.com/200-million-60-minutes-filecoin-ico-rockets-record-amid-tech-issues/ <comment><USER2> Amazing, although I am not sure I understand their business model correctly. So they are a middle man for digital storage rental and those transactions are done in Filecoins that only they can mine and distribute? So that company has >$200M in cash now or who gets that money? And the investors are in because they saw the surge of Bitcoin (and now of Filecoin)?

</comment><comment><USER3> How will these storage coins stop cheaters? Why can't I claim that I will store your data and just not do it?

<comment><AUTHOR> Check out their whitepaper [https://filecoin.io/filecoin.pdf](https://filecoin.io/filecoin.pdf)

It includes two proofs, proof-of-replication and proof-of-spacetime which help prove someone is storing the file multiple times in independent locations.

<comment><USER3> It looks like some kind of zero knowledge proof. Why I can't just generate that and then discard your data?

<comment><USER4> Because you need to keep proving over time

<comment><USER3> Reading the paper I get the idea. Although it's possible to cheat, nodes have to put filecoins at risk of loss if they get caught.

</comment></comment></comment></comment></comment><comment><USER5> Who is putting up this kind of cash?!

<comment><USER6> Accredited investors ;-) Didn't notice the difference with non accredited ones.</comment></comment>