Schneibster

I couldn't listen to the video, just watch it; something funny with my system no doubt. I read the article and extrapolated from "rail gun." Whatever they're doing, it's not technically a rail gun, which is purely electromagnetic. I'm still trying to figure what's making flames come out the muzzle.

The sabot trick was what they used for the penetrator DU rounds in tanks; I guess you're familiar with the details of that, swansont.

Obviously what they're doing there is barely capable of hitting a single hard target, a tank or (in the video) truck.

Thanks for running the numbers, John Cuthber. I was gonna get up today and do that. You're right, it'll take a heckuvalot more velocity, or mass, to hit hard enough to outperform, say, the New Jersey's main guns which throw a projectile the mass of a Volkswagen some twenty miles or more. (I'll go look up the details if anyone's interested.) This thing they're playing with in the video is a toy compared to that.

23 pounds, delivered at Mach 7 a hundred miles away. This explodes like a nuclear weapon, without the radiation or the fallout. No explosives. It's just the kinetic energy of the slug. All heat nothing more. Iron is presumably the best material. It's highly magnetic and therefore ideal for railgun acceleration.

http://complex.foreignpolicy.com/posts/2014/04/07/watch_the_navy_s_futuristic_star_wars_railgun_blow_things_up

This article is from my favorite foreign affairs site. You will have to register, but you will be able to view ten free articles every month, and comment on them.

If you don't want to register, then here is the direct Vimeo link:

Bear in mind that actual use of the weapon against targets has never before been shown on any medium. I doubt this has seen public viewing on a science site up until now. Enjoy.

The missing link is what to do with the CO2.

Feed it back in!

This is actually a US Navy project, and they claim jet fuel for $3/gallon.

http://www.nrl.navy.mil/media/news-releases/2014/scale-model-wwii-craft-takes-flight-with-fuel-from-the-sea-concept

The US Navy has always tried to be green-- it makes them more effective. This little trick could make them no longer require fuel from land for an aircraft carrier; just food and clothing and cleaning supplies. And people.

And wherever they went they'd reduce CO₂.

In this recent paper from Michael Mann, the recent so-called "global warming slowdown" is shown to be indistinguishable from the Atlantic Multidecadal Oscillation, or AMO, previously called the "NAO" or "North Atlantic Oscillation" before its full character had been measured. Dr. Mann's original "Hockey Stick" paper was based on study of the NAO, so this is familiar data territory for him.

Mann says,

"Some researchers have in the past attributed a portion of Northern Hemispheric warming to a warm phase of the AMO," said Michael E. Mann, Distinguished Professor of Meteorology. "The true AMO signal, instead, appears likely to have been in a cooling phase in recent decades, offsetting some of the anthropogenic warming temporarily."

So another denial falls by the wayside, and global warming wins again.

Full details are available here and I will be fairly available for questions unless ajb takes up all my available CPU cycles.

I was gonna gig you on that use of "constant," speaking of

I think it was a true triumph that the Gravity Probe B folks managed to find their problem, and not only that but correct for it and reanalyze the data. Now THAT required asking the right questions. (A good schneibster always asks good questions. I am a connoisseur, IOW.)

I think they found out what the Pioneer Anomaly was, last time I checked. Extra heat radiation pressure from the reactor?

This is a measure of the expansion of the universe at high redshifts (z > 2) to unprecedented accuracy: circa 2%. This is using the new Baryon Acoustic Oscillation method pioneered by BOSS, this time with three times as many individual objects measured as previously to get the original high resolution results. The current measurements use over 150,000 quasars, as opposed to the last results which used 48,000 and the original survey results which used only 16,000 quasars.

"Three years ago BOSS used 14,000 quasars to demonstrate we could make the biggest 3D maps of the universe," says Berkeley Lab's David Schlegel, principal investigator of BOSS. "Two years ago, with 48,000 quasars, we first detected baryon acoustic oscillations in these maps. Now, with more than 150,000 quasars, we've made extremely precise measures of BAO."

http://newscenter.lbl.gov/news-releases/2014/04/07/boss-quasars-measure-expansion/

This approach obviously is one of the most effective possible, and it's good to see astronomers starting to gain the data processing expertise to identify the algorithms to achieve these results. We can look forward to surveys of this type of a million objects in the next decade (and that's pessimistic).

As it is, we already have SDSS surveys with photometry of over 500 million (half a billion) objects, and spectra for over a million of them. And the surveys are automated, computerized, and ongoing.

So far AFAIK it hasn't been measured, and I won't bet on it; it's not enough of a sure thing for me.

Also I'm not sure it wouldn't affect other parameters if it were true. I'm thinking of the speed of light, and the scale of the universe, and obvious stuff like that. It's just a conjecture.

In modern cars they can blow confuse the mixture computer, which fails safe and turns off the gas. (I don't think they're going to use something that will blow peoples' computers on the far side of the freeway.)

As davidivad hints, there are hints about the construction of such devices most of which involve magnetrons and ultracapacitors and vaporize their wires. You can find a lot of sites of varying credibility that talk about them. I've never stepped up and done the math and engineering to prove it, but my sense of the magnitudes involved says your friend is not being outrageous at 5 meters distance, but I'd be surprised if it would actually smoke the circuits as opposed to just temporarily interdict communications. A true EMP will burn transistor junctions. That takes a lot of power. I mean a lot. The first EMPs were made with kiloton (i.e. terajoule) nuclear weapons. You really don't want a terajoule being suddenly released anywhere in your near neighborhood even if you have a blockhouse. And you sure as heck aren't doing it with a magnetron the size of your fist.

I've seen articles that claimed a thousand pounds of ultracapacitors and a magnetron the size of a watermelon and worked over a distance of hundreds of meters/yards, no more. It seems like a good way to smoke all the electronics in an enemy tank; needs work to be feasible in aircraft. Interesting as an anti-missile close-in weapons system, fry the electronics before the missile can get close enough to hurt you. Need some serious cybernetics work though before it would be practical. Also you'd need to have shielded systems yourself to fire it off; it's just not that easy to make a thing like that all that directional. The backlash could smoke your fly-by-wire computer. After which you become aerodynamically unstable. At Mach 2. Bad idea. Think fly on freeway waiting for the windshield.

I've seen articles that talked about purpose-designed EMP nuclear weapons, blown off in the ionosphere to maximize the pulse and spread it over a continent. Megaton-range devices are discussed IIRC.

Megawatt radar arrays on guided missile cruisers of the great powers are said to be able to smoke the electronics on aircraft that fly through the beam too close; this is at the edge of believable with systems fifteen years old, and eminently possible these days as the synthetic aperture phased arrays have crept up into the tens of megawatts.

Which kind are you talking about? Or are you talking about another technology?

Sorry but if you won't answer questions I can't figure out where you've made your mistake.

Your understanding of vacuum energy as measured in a Casimir apparatus seems correct to me. Specifically, the waves between the plates are less than the waves outside the plates. The amount, however, is not infinite.

So your objection doesn't look correct to me, but not conceptually; only in terms of your assumptions about the quantities involved.

OTOH, it's several orders of magnitude so your objection isn't ridiculous, just ruled out. Remember that although there may be an infinite universe outside the plates, only the waves that strike the plates register; and that's as true on the outside as the inside.

This accounts for the frequent statement that expansion happens in the empty space between galaxy clusters. It's because it's not flat space inside them, but it's flat in the space between. If we measured the Casimir force in flat space it would be stronger. This latter is the experiment we'd need to perform to prove it.

The Bay of Bengal and the Marshall Islands are good candidates for the next wave.

So you deny something from that post?

Could you be explicit about what you disagree with, please? I'm unclear from what you've said what the problem is. All of those propositions look fine to me and you're in the process of agreeing with each one piecemeal. So far you're getting impatient with me trying to figure out what you think is wrong. Maybe if you'd say something other than "your conclusion" and start discussing why the conversation might be productive more quickly. That conclusion, I'll point out, was not mentioned in that post, so actually you still haven't answered my question.

Meanwhile, fine, so you admit mass comes into the Dirac equations for fermions through the Yukawa interaction with the Higgs scalar field, and you admit that the Dirac field defined by those equations is explicitly specially relativistic. Right?

Now, do you deny that the rest mass that the Lorentz transform acts upon is the rest mass determined by the Yukawa interaction with the Higgs field?

BTW, not sure what the claim that the Dirac field, i.e. the fermion field, is not Lorentz symmetric, is based upon. In fact the anticommutation of the half-integer spin fermions is determined explicitly due to Lorentz symmetry; it is therefore responsible for Pauli Exclusion and their other obedience to the Fermi-Dirac statistics. I have no idea what claiming the Dirac field is not Lorentz symmetric means.

I asked it twice in post 75.

What "claim" are you talking about?

More or less that is what I have been saying.

OK, now we're getting somewhere.

Do you deny that the Dirac field is explicitly Lorentz symmetric, i.e. incorporates special relativity?

I'm no physicist. Can't you do that?

I note you avoided my question.

I'll try each point in turn instead.

Do you deny that the Higgs field determines the rest mass that is an input to the Dirac field equations of the fermion field, through Yukawa coupling of the two fields?

Let's try this again:

Higgs field ->

Scalar field

Extremely simple has only one interaction besides self-interactions

couples through Yukawa interaction with

Dirac field ->

Yukawa interaction with Higgs field provides "rest mass"

Dirac field is more complex, provides many attributes

Dirac field is explicitly relativistic, incorporates Lorentz symmetry

Lorentz symmetry acts on "rest mass" (see above)

Now

mass ->

more properly mass/energy or stress-energy tensor

Acts upon all three both of

Ricci tensor

metric tensor

cosmological constant

And is in turn acted upon by them.

Are we good so far?

I want to understand this statement. Please show me where it has come from.

I'm working on it. Please answer if we're good so far.

Note, updated once.

No, I made a series of statements. Denying the last one is bad form. Prove which one that preceded it you disagree with. Or prove what's missing from them.

Yes, the rest or invariant mass.

Yes. The Yukawa interaction brings that in from the Higgs field.

Can you show me?

I believe I just did.

The Dirac theory's relativity acts on the mass attribute determined by the Yukawa coupling between the Higgs field and the Dirac field, is my point.

The point being that it's not the velocity that the Higgs field couples to. That coupling is not through the Higgs field but through the Dirac field.

The Higgs field's Yukawa coupling strength increases with acceleration.

Ummm, the Dirac theory is relativistic.

Explicitly. That's Standard Model.

More accurately it is Lorentz symmetric, which is the same thing. Lorentz symmetry is the symmetry of SR. You can look at it as, it's the symmetry that makes the Dirac field anticommutate.

Right. The relativistic mass comes from the Dirac theory of the fermions. The Higgs field gives them mass, and then the Dirac theory makes it relativistic. Mass is an input to the Dirac theory, not an output. It is an output of the Yukawa coupling of the Dirac theory with the Higgs field.

I am wondering if the difference in the magnitudes of the Casimir force as measured in the lab, and the necessary strength of lambda, the cosmological constant, or "dark energy," could be due to the fact that it is offset by a change in g_uv due to the local density of matter within the galaxy, or within the Local Cluster.

Sam, I'm sorry, I think you're trolling for a reaction and you have confirmed my opinion by denying the Big Bang.

So, again, what's wrong?

You're factually incorrect, BTW, my description of rapidity is straight doctrine.

Yes I believe we've established that already..........

Then why blame relativity for it?

Sam, I'm sorry you're upset but you're still just denying, and you're still not answering the essential question, "What's wrong?"