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Comment Re:It's like winning the lottery! (Score 4, Informative) 255 255

The browser UI is new, but the rendering engine is still based on Trident. They just removed all the legacy stuff, and focused on clean implementations of the standards without worrying so much about backward compatibility. Edge will puke about as badly as Chrome or Firefox will if fed code and markup intended for IE7, instead of falling back to IE7's rendering style.

Which isn't to say there aren't going to be security bugs, of course. But then, the same is true of all the big browser vendors.

Comment Re:Physics time! (Score 1) 511 511

Yep. Those kinds of experiments get expensive, though. There are only a few systems in the world sensitive enough to reliably (i.e. without risk of error from outside sources) detect thrust on the levels we're talking about, even at 10x the power of the current experiments. Another problem is that they need to cool the thing. It sounds counterintuitive, but cooling stuff in a vacuum (such as they are using for the current rounds of testing, to eliminate the risk of errors due to things like convection currents) is hard. That makes it difficult to run a high-power magnetron.

Comment Re:Physics time! (Score 1) 511 511

Possibly. I don't actually know anything about quantum virtual particles except what I've read related to the theories on how the EM Drive might work. I've got a BS in computer engineering, not a PhD in physics. I can believe that Hawking could have shown that, but I don't know if it has or has not been shown.

Comment Re:Physics time! (Score 1) 511 511

Empirical observations trump theory. Theory is an attempt to explain how the universe works, but it does not dictate the universe's workings. Grad-level physics can explain why the EM Drive shouldn't work. Newtonian physics can explain why GPS shouldn't work, too; and yet the accuracy of the results remain as high as ever.

The problem is, according to everybody who has tested it, the EM Drive does produce thrust. When your theory contradicts reality, it is the theory which is discarded (or at least updated). Unless there's some pervasive experimental error in all of the independent observations of this effect - which is possible, but becomes less likely with each successful reproduction - that will need to happen with our understanding of those grad-level physics you studied.

In that case, on your final, you did the equivalent of computing that if a 1kg object (constant mass, initially at rest relative to you) produces 10^8 N of thrust in a straight line away from you for six seconds, it'll be going at just over twice the speed of light relative to you afterwards. Perfectly consistent with physics as it was near-universally understood until 110 years ago...

Of course, in this case, we have an experimental result before we have a fully consistent theory to explain it. In a reversal from the way much (though not all) recent physics progress has been made, the empiricists appear to be outracing the theorists. That's why right now there are a number of hypotheses, each of which have problems. More experiments will allow us to refine those hypotheses and throw out those which are shown to be incorrect (for example, Guido Fetta - of the Cannae Drive - had a theory that radial slots inside the drive's chamber were required; NASA demonstrated that they weren't). More time will also allow theoretical physicists to work out the underpinnings of how this happens. That will expand our understanding of the universe, give us the tools to predict future experimental results (rather than trying to explain the result after the fact), and open new branches of scientific exploration.

The above paragraph is, of course, predicated on the assumption that the effect does happen. I'm not discarding the possibility of experimental error at this point. It is simply becoming less and less plausible of an explanation.

Comment Re:Physics time! You misunderstand ion drives (Score 1) 511 511

First of all, a horse cannot continuously accelerate given a constant amount of electricity (or even hay). Horses need to push against something (the ground) and can only do that so fast; there is a cap on their maximum velocity. In practice, for any given real-world flywheel and generator, there would be a max speed for an EM Drive-driven rotor too - due to centrifugal force, if nothing else - but there's no theoretical maximum that I'm aware of.

Read david_thornley's comment above for the math. The basic idea is that if you have something which increases its velocity at a constant rate and for constant energy, then its kinetic energy growth will eventually exceed the energy driving it. That's because kinetic energy grows as the square of velocity.

Of course, a conventional rocket could accelerate continuously (unlike a horse) if you could keep it supplied with fuel. That's the big "if", though; the total energy you could get out of it is never more than the rest energy of the fuel you put in. Imagine a total-conversion antimatter rocket, which is probably the most efficient kind of reaction drive possible (since you are literally extracting all the energy possible from a given mass). It produces an incredible amount of energy for the fuel you put in... but at the end of the day, it runs out of fuel (stops accelerating) and you have to put more in, consuming the mass/energy of something from outside the system. It can't run forever without consuming an infinite amount of mass.

The EM Drive has no fuel requirement at all. Electricity isn't a thing that can be consumed, it's a process, the motion of electrons. A generator can keep applying (electromotive) force to those electrons, keeping them moving forever as long as there's an energy input to the generator itself. The EM Drive can keep producing thrust as long as it has electricity. Once you reach the break-even point, no outside mass/energy is required.

Comment Re:Physics time! (Score 4, Informative) 511 511

Except it doesn't. The microwaves are not emitted anywhere. They are generated into a sealed chamber. There's nowhere they can go.

The formulae you listed would be useful to describe thrust from a photon drive (or light drive), but those need an open-ended emitter. Also, the results you get from them are about three orders of magnitude too low for the observed ratio of thrust to power. A 700W microwave photon drive wouldn't be detectable by the experimental apparatus.

Comment Re:Physics time! (Score 4, Insightful) 511 511

A) That's one hypothesis among several, and many physicists claim it is, to use your term, "bollocks". I did mention there are multiple theories about how it works. They all have supporters, but they all have counterarguments too.

B) No, classical rocket engines push real particles one way and itself the other way. Unless you intend to claim that "virtual" and "real" particles are the same thing, it's not working "exactly the same way". Analogously, perhaps, but hardly "exactly the same".

Oh, and just for the heck of it:
C) To conclusively state that the EM Drive works according to your preferred theory is quite absurd unless you're an extremely well-educated theoretical physicist, and only slightly less even then. To even *claim* that I claimed anything about how the drive works, much less that my supposed idea is "bollocks", indicates a lack of reading comprehension, lack of understanding of the concept of scientific hypotheses, and lack of maturity.

Good day to you.

Comment Re:Blimey (Score 1) 511 511

Not indefinitely, just over a long time. Ion engines consume fuel (which they ionize, and then throw the ions out the back of the drive, hence the name) so an ion engine still needs to haul its reaction mass along for the ride, and stops being able to thrust once it runs out of stuff to ionize and expel.

Comment Re:Blimey (Score 1) 511 511

The fuel (energy storage) used to produce the electricity doesn't need to be internal to the craft, though. Photovoltaic panels, for example, take electromagnetic energy (photons), such as stars (big balls of fuel) produce, and turn it into electricity. A magnetron (such as the one inside an EM Drive) can turn that electricity back into electromagnetic energy. You now have a relatively tiny craft that can thrust forever so long as there's a star close enough to provide photons (in reasonable quantity). Maybe not viable for a starship, but it could completely revolutionize intra-system travel.

Comment Physics time! You misunderstand ion drives (Score 3, Informative) 511 511

I wrote a comment on this up above, but just to help you understand...

1) No, the ion drive does not use electricity to produce thrust. Ion drives, as their name suggests, use ions to produce thrust. The ions are accelerated using fields generated via electric power, but that's no more a case of using electricity to (directly) produce thrust than an electric car is (the car pushes against the road, imparting momentum to the earth which balances the momentum imparted to the car).
2) Yes, it sounds like a free energy machine. If a given amount of electrical power produces a given thrust, constantly, without consuming any fuel, then you can generate unlimited energy by attaching this thing to a flywheel or rotor arm that drives a generator and it will produce more energy than it requires to drive the thruster. Some of the current theories about this thing claim that it won't do that, that its efficiency will go down the faster it's moving (relative to a given frame of reference).
3) No, electricity is not fuel. Electricity is not a thing. It is a process. Electricity is the motion of electrons. It is a form of energy. Fuel is a way to store energy, but it is not energy itself. You can generate electricity from many things, including fuel, and there are many forms of chemical devices with electrical potential energy - we usually call them batteries - but electricity is not, itself, fuel. Now, the energy still needs to come from somewhere (unless this drive does turn out to be usable to get more energy out than is put in, which would turn *all* of physics on its head) and that "somewhere" is usually fuel of some kind... but it can be things like uranium in a nuclear reactor that is usable for decades from a tiny amount of mass, or hydrogen in the sun producing photons as it fuses and those photons being captured and used to move electrons via the photoelectric effect (in layman's terms, solar panels).

Comment Full Text + links from Hacked.com (Score 5, Informative) 511 511

Scientists Confirm 'Impossible' EM Drive Propulsion

Science News, Space / July 27, 2015 / by Giulio Prisco/

Later today, July 27, German scientists will present new experimental results on the controversial, "impossible" EM Drive, at the American Institute for Aeronautics and Astronautics' Propulsion and Energy Forum in Orlando. The presentation is titled "Direct Thrust Measurements of an EmDrive and Evaluation of Possible Side-Effects."

Presenter Martin Tajmar is a professor and chair for Space Systems at the Dresden University of Technology, interested in space propulsion systems and breakthrough propulsion physics.

A Revolutionary Development for Space Travel

The EM Drive (Electro Magnetic Drive) uses electromagnetic microwave cavities to directly convert electrical energy to thrust without the need to expel any propellant. First proposed by Satellite Propulsion Research, a research company based in the UK founded by aerospace engineer Roger Shawyer, the EM Drive concept was predictably scorned by much of the mainstream research community for allegedly violating the laws of physics, including the conservation of momentum.

However, NASA Eagleworks – an advanced propulsion research group led by Dr. Harold G. “Sonny” White at the Johnson Space Center (JSC) – investigated the EM Drive and presented encouraging test results in 2014 at the 50th Joint Propulsion Conference.

White proposes that the EM Drive’s thrust is due to virtual particles in the quantum vacuum that behave like propellant ions in magneto-hydrodynamical propulsion systems, extracting "fuel" from the very fabric of space-time and eliminating the need to carry propellant. While a number of scientists criticize White's theoretical model, others feel that he is at least pointing to the right direction. The NASASpaceFlight website and forums have emerged as unofficial news source and discussion space for all things related to the EM Drive and related breakthrough space propulsion proposals such as the Cannae Drive.

Shawyer has often been dismissed by the research establishment for not having peer-reviewed scientific publications, but White and Tajmar have impeccable credentials that put them beyond cheap dismissal and scorn. Physics is an experimental science, and the fact that the EM Drive works is confirmed in the lab. "This is the first time that someone with a well-equipped lab and a strong background in tracking experimental error has been involved, rather than engineers who may be unconsciously influenced by a desire to see it work," notes Wired referring to Tajmar's work.

Hacked has obtained a copy of Tajmar's Propulsion and Energy Forum paper, co-authored by G. Fiedler.

"Our measurements reveal thrusts as expected from previous claims after carefully studying thermal and electromagnetic interferences," note the researchers. "If true, this could certainly revolutionize space travel."

“The nature of the thrusts observed is still unclear.”

"Additional tests need to be carried out to study the magnetic interaction of the power feeding lines used for the liquid metal contacts," conclude the researchers. "Nevertheless, we do observe thrusts close to the magnitude of the actual predictions after eliminating many possible error sources that should warrant further investigation into the phenomena. Next steps include better magnetic shielding, further vacuum tests and improved EMDrive models with higher Q factors and electronics that allow tuning for optimal operation."

Contrary to sensationalist reports published by the sensationalist press, the EM Drive is not a "warp drive" for faster than light travel. It could, however, according to current experimental evidence, be a revolutionary development for faster and cheaper space transportation.

Wired notes that an EmDrive could get to Pluto in less than 18 months and mentions more ambitious ideas including a manned trip to the moons of Saturn with a three-year mission time. "Some damage to our theories of physics is an acceptable payoff if we get a working space drive," concludes the Wired article.

Comment Re:Interesting, but still a lot of hype (Score 1) 511 511

Finally, in the hacked.com article, rather than expelling "propellant", aren't you expelling "reaction mass"?

Where did you get that idea? The article never uses the term "reaction mass" (or even either word individually). The only references to "propellant" are to explain what the EM drive *doesn't* use, or to contrast the EM Drive with ion drives (which do have a propellant, the ions that the drive expels).

Also, for the record, "reaction mass" is just "propellant" that has been given momentum and kicked out of the vehicle. They are the same thing at different points in time, and the terms are often used interchangeably.

Comment Physics time! (Score 5, Interesting) 511 511

It appears to impart momentum to something without an opposite momentum imparted to anything else... you know, the basic concept of how every other propulsion system in the world works?

When you walk, your feet push against the ground, imparting a (tiny, relative to the mass of the Earth) amount of momentum to it at the same time that your feet impart momentum to your body.
When you sail a boat, the sails alter the momentum of the wind, and an opposite alteration is imparted to the momentum of the boat.
When a rocket engine fires, it releases exhaust with a lot of momentum going one way, and the rocket receives the momentum going the other way.
This model holds for any kind of propelling of anything. Even a flashlight projecting photons imparts a tiny, tiny bit of momentum to your hand, to your body, to the earth. Magnetic propulsion, chemical propulsion, ion propulsion... all of them operate on the principle of "we go this way, by making something else go that way".

The EM Drive appears to go one way without making anything else go the other way. It releases no exhaust, pushes against no solid or fluid, emits no photons, and interacts with no external magnetic fields. We don't know how it works (there are a number of theories, none of which are that widely accepted), and we still aren't 100% sure it does work (maybe it's still all experimental error... that becomes less likely with each independent verification, but extraordinary claims call for extraordinary evidence), but if it does work it does so in a way that is outside our current understanding of physics. That is a Really Big Deal.

One way or another, this is exciting!

Comment Re: Looking more and more likely all the time... (Score 3, Interesting) 511 511

Yep, the microwave cavity is sealed. Nowhere for them to go.

Also, even in these early and probably very inefficient (assuming the thing really works) trials, the thrust/power ratio is something like three orders of magnitude beyond what you'd get from a photon drive. No "microwave-emitting thruster" operating at these power levels would come even close to the sensitivity threshold of the experimental apparatus, much less reach several times that threshold.

Comment Re:im sure the news on Kepler 452b was grave. (Score 2) 134 134

That's actually not *entirely* true... humans haven't been making artificially modulated RF for a millennium yet, but artificial sources of EM (remember, *light* is EM) have existed practically as long as any form of civilization has. Cities are visible from space. Much less so when they're lit by candles and fireplaces than when they're lit by all the myriad electric sources found in modern cities, and there's a nearly-incomprehensible difference between LEO "from space" and interstellar "from space", of course. It also wouldn't tell the aliens anything about us (even if they had the sensors to detect those tiny motes of firelight, and distinguish them from natural sources) other than that we'd invented fire. Still, that's a lot, in some ways.

It is not best to swap horses while crossing the river. -- Abraham Lincoln

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