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Comment: ...of Government and Enterprise Working Together (Score 1) 62

by Roger W Moore (#49827861) Attached to: Mystery Company Blazes a Trail In Fusion Energy

This is exactly why you let private entrepreneurs do things rather than the government. It'll get done better, cheaper, and faster.

Actually you will typically only get two out of those three. Saying that there should never have been any tax spent on this is really not understanding what these entrepreneurs are doing. The reason that any of these startups are even possible is because of the huge amount of work which has been done on fusion in the past by governments. If none of that money have been spent there would be no fusion start ups because we would not have enough knowledge about fusing plasma to make any sort of even vaguely viable bid for investment funding. In addition some of the startups are actually get tax money to help them startup.

Rather than denigrate the government paid research that got us here you should be looking at a research system which is doing exactly what it should be and working extremely well as a whole. The, yes often ponderous, ship of state takes science on the long, risky and costly journey across a vast ocean of knowledge which does not appear to be very relevant to improving our quality of life until it gets within sight of something extremely useful. Then the entrepreneurs take over and rapidly construct a fleet of many different craft to get to the new shore which is now in sight. Most will sink without trace on the way to that shore but those that arrive rapidly explore and open up new territory for us all to benefit from.

So what we have here is a great example of the system working as it should. It's not a case of tortoise vs. hare and more a case of the tortoise carrying the hare until it is close enough to the finish that it can sprint across the line and win the race faster than either one could by themselves. Government research is slow and it is expensive but that is because they take on the big, slow and expensive research which private enterprise lacks the stamina to do. A successful team plays to each member's strengths and that's exactly what appears to be happening here. So don't complain - all those tax dollars you probably previously complained were wasted on fundamental research may well be about to be paid back ...and with a lot of interest if any one of these companies are successful.

Comment: Re:Odd thoughts: (Score 1) 222

by BitZtream (#49827485) Attached to: Microsoft To Support SSH In Windows and Contribute To OpenSSH

BSD tools are pretty standardized yes.

UNIX tools are specific, its a certification.

GNU/Linux is a SysV bastarded child formed by merging a pretty great kernel with any number of half assed intentionally incompatible in subtle ways user land utilities.

Nothing about Linux is BSD or UNIX other than the feel. Windows is in fact more UNIX than Linux is, with its posix certified interop layer that Linux supports well, but is not certified.

A older version of OS X is UNIX and Posix certified.

Comment: Re:What use? (Score 1) 135

by tnk1 (#49822591) Attached to: Facebook Now Supports PGP To Send You Encrypted Emails

Yes... if you send your emails to people through a Facebook client, instead of downloading the key and sending encrypted mails via your own email client.

Aside from actually doing something stupid like sending emails from FB (where you'd have to trust them anyway to not store your unencrypted text before they encrypted it for you), there is actually no issue with Facebook or the United States doing this.

FB hosting your public key has zero effect on anything. You are supposed to distribute your public key widely. The actual problem with public keys is ensuring that your public key is actually your public key for the purposes of not sending an email that someone else can read.

For that, you need to actually send an email with that key and then (usually over phone or in person) confirm that the recipient:

a) Got the email (proving that the email address isn't sending it to some other mailbox)
b) The recipient can decrypt the mail with their secret key.

If the recipient gets the email, but they can't decrypt it, then the public key is incorrect and would be discarded.

This verification process is the hard part for random people downloading keys and sending emails to addresses of people they've never met, although in practice, if you have any real world contact with your recipient, the verification feedback is usually pretty easy to come by.

MITM attacks would presumably require you to be able to intercept mails to the email address of the supposed recipient, you would then decrypt the email, store it, and then re-encrypt it with the actual recipient's public key and forward it on. That requires, however, a significant investment by the attacker, not to mention a not inconsiderable amount of authority to create some sort of email interception proxy.

It can also easily be thwarted by the uploader of the public key logging in as another person or anonymously and comparing the key that FB provides with their known good key. If the key doesn't match, then you have MITM possibilities and you simply remove your public key and call the Washington Post for an expose on FB's MITM of your public key encryption.

Comment: November Revolution (Score 1) 59

I doubt any revolution in particle physics would ever come from *WITHIN* particle physics.

Really? It has already happened once with something called the November Revolution. This was the discovery of the charm quark which completely revolutionized our understanding of what baryons and mesons were and ushered in the quark model.

Prior to that there was the prediction of anti-matter by Dirac followed by its discovery a few years later which showed that we could unite quantum mechanics and Special Relativity. Prior to that there was Rutherford's discovery of the atom which completely changed our understanding of the nature of matter and all the early work with particles which lead to quantum mechanics. In fact if you look back at the last century or so of physics many of the major paradigm shifts in the field have come from particle physics or its clear precursor.

If you think that getting a PhD merely requires you to accept certain beliefs then you have a very poor understanding about how science works. Good PhD students will challenge the beliefs of those examining them and defend their work using the data and analysis they have in their thesis.

As for damaging careers coming up with some radical new idea will greatly enhance anyone's career...provided that they put in the ground work to do the studies needed to convince others of its worth. Big experiments are an issue because the amount of ground work to get one of these funded is huge and this limits the scope of ideas to ones which are clearly going to work.

Lastly though as for thinking of the Standard Model as the truth absolutely nothing could be more wrong. In fact we usually start by pointing out one of its most obvious flaws: there is no gravity in it! Indeed we particle physicists spend all our time trying to break it by looking for physics beyond what it allows for. Whoever finds physics beyond the Standard Model is likely to end up with a Nobel Prize so I'm not sure why you would think we would not he extremely motivated to break it and why this would not be really good for anyone's career.

Comment: Depends on Comparison (Score 2) 252

by Roger W Moore (#49819889) Attached to: Fuel Free Spacecrafts Using Graphene

However, electrons are very nearly massless, so unless they're somehow exciting them with massive amounts of energy, the propulsion from the electrons is unlikely to be significant.

It depends on what you compare it to. Since this process was hitting the graphite with photons it makes sense to compare the thrust produced to that created purely by bouncing photons off a material. Electrons might be light but they have more mass than a photon and so the thrust should be significantly higher.

Comment: No Charge Violation! (Score 2) 252

by Roger W Moore (#49819151) Attached to: Fuel Free Spacecrafts Using Graphene
That may be correct but the article you linked has an incredibly misleading title. This process does not convert photons into electrons it simply imparts the photon's energy to one or more electrons which, in the case of thrust, causes them to be ejected from the graphite. The coupling of electrons to photons is extremely well understood, in fact it is the second most accurately tested scientific theory ever discovered (the first being special relativity). The only way to create electrons from photons is to also create an equal number of positrons. However this requires far higher energy processes ~1 MeV of energy which is many orders of magnitude higher than the energies involved in visible light and would easily break apart graphite which is something they ruled out.

Comment: In lab = Surrounded by Electrons (Score 1) 252

by Roger W Moore (#49819081) Attached to: Fuel Free Spacecrafts Using Graphene

Where the heck those extra electrons came from?

They could easily come from all the material which is surrounding the graphite. As the charge builds up on the graphite due to all the electrons being expelled it will develop an increasingly strong electric field eventually will pull electrons from the walls of the chamber. Since the vacuum will also not be perfect the remaining gas molecules could also transfer charge by moving back and forth between the graphite and the chamber walls.

A similar effect exists in the LHC where the electrons are 'helped' to leave the walls by synchrotron radiation hitting the walls of the beam pipe and are then dragged along by the electric field of a bunch of protons forming a electron cloud. This effect is one of the primary limiting factors on the number of protons we can have in an LHC beam.

Comment: Even More Thrust (Score 2, Interesting) 252

by Roger W Moore (#49819015) Attached to: Fuel Free Spacecrafts Using Graphene

So they'd need to carry hydrogen and split off its electrons or something to neutralize the charge.

Actually this could provide more thrust. Use sunlight to propel the craft until it has built up a large enough electric charge that the efficiency of the thrust begins to drop (since it will take an increasing amount of energy to expel the electrons from something with a large positive charge) and then introduce a stream of neutral gas into the sponge. This should strip the electrons off the gas and the remaining positively charge ions will then be repelled by the positive graphite and provide even more thrust.

Of course this means that you need to have a fuel source but it's likely to be far more efficient than current rocket fuel plus there it no need for it to be something explosive like hydrogen - you could probably use Xenon which is a noble gas and so extremely inert and so a lot safer.

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