Schneibster

Snicker @ "LASER" Backronym. Meanwhile, I'd expect a random flat surface reflection to be fairly limited in angular scope even at that long a distance.

Moontanman, that's tough, but if you can't get someone to believe molecular biology after all we can do, including create new living species in the lab, not to mention organisms that are alive but are clearly not anything that ever evolved on Earth, then your friend insists on ignoring reality and you should tell her so. She's welcome to deny whatever she wants, but that doesn't make it real and you should tell her so, and tell her of your concerns that she is ignoring reality. You will never convince her but you can at least make her think about it.

Dr. Lohse has found a subtle genetic method for confirming the difference between the first and second scenarios above. This method has positively ruled out the second scenario. It is certain now that Homo Sapiens Neanderthalensis and Homo Sapiens Sapiens interbred on occasion, and modern humans of all so-called "races" have inherited genes from these occasions. The press release is here; I look to the geneticists among us to check out the scholarly paper (linked in the press release) and tell us all what we're looking at in terms of the details of the new method.

I expect it was all the footage the reporter on FP could find on short notice. They're going through a "Hey, look at all these awesome graphics 'n' stuff on this new Internet thingie!!" phase right now. I have to close their window and only open it when I want to surf them so they don't overwhelm my CPU. I've summarized our results back there (I'm a full subscriber to FP) and we'll see what I hear back. Meanwhile I also mentioned "no explosive magazine risk" as a possible advantage; thanks you guys. And I have thought about the range, which is impressive to say the least. They can hit anything in the littoral. I think the most important thing is how many projectiles they can put on target before the target can react. Even if they're small, any aircraft hit is down for days. Furthermore, there is the durandal effect on the runways; planes are no good if you can't launch them and you can't launch them if they're full of holes. If they can put hundreds of these on target in minutes, it will be like lightning raining down from Gawd guided by satellite. Another important point is that they can put small force on target a hundred miles away. Never mind drones, these things are almost as small as Hellfire missiles drones use. And the drone's data showing the target location can be fed to this gun, and a projectile can land a hundred miles away that only takes out one or two rooms in a house, instead of the whole block. And no explosives.

It's plausible. Since I'm not being paid I'll leave it to a real mathematician (and there are some here) to comment on whether it will actually work. If it does work, then if you can design the algorithm right in terms of primitives you'll get something that's ripe for compiler optimization in a RISC. This is an assembly/machine language level optimization, however, something you do in a compiler, not in, say, C or Fortran. That's my opinion as a CS. You should wait for a mathematician to confirm the algorithm works.

I didn't even dare respond to that. I know a senior VP Dekan should meet for the improvement of attitude. She's a redhead.

When I run a Windows box, I run Eset's antivirus; it's the lowest footprint of any of the major non-free solutions. I use browser utilities for internet security, as well as a firewall. If I can do my outgoing connection and incoming connection security at the firewall, I save CPU cycles.

On ekpyrotic theory? No, no books. On physics, if you're working on a chemistry degree you're already getting a lot. I think the two best-known Brian Greene books are your best bet if you don't want to take on the heavy-duty math of string physics. (The Elegant Universe and The Fabric of the Cosmos.) This will give you the operating principles, and let you choose where you need to delve deeper. If you need to beef up on the real basics, try The Force of Symmetry by Vincent Icke. No string theory in that, though; OTOH, a darn good overview of everything short of it, from a not-so-much-math perspective that won't strain your brain when you're taking a break from cramming for a mid-term. It's quantum and relativity physics for liberal arts majors. You won't be able to drive the locomotive but you'll know where all the important knobs, buttons, levers, and control wheels are.

And as I said, your interpretation fails. As far as defining motion myself, I use the appropriate definition for the circumstances. And I remember it's relative. There isn't any one definition that suits all circumstances.

Well, then you're using "Lorentz symmetric" in a completely different manner than I'm used to. So you're saying that "Lorentz symmetric" is something that can only be said about a scalar? It's not something a complex field inherits from the scalars that make it up? And also, several parts of the Dirac field do transform. So I'm not sure what you mean when you say it "does not change under a Lorentz transformation." I suspect the problem is deeper; that your definition of "Dirac field" is different than I'm used to.

Starting John Shirley's "A Song Called Youth," first novel Eclipse. This is the Babbage Press quarto paperback edition from 1999, not the original 1985 octavo paperback edition which I also own. I'm looking forward to Rickenharp jamming on top of the Arc de Triomphe with a battery-powered Marshall as the giant nuclear powered swastika war machines advance to demolish it. Iconic stuff.

Well, I haven't learned anything yet. At least not anything that I was wrong about. The Dirac field is the spin 1/2 Fermi-Dirac particles, or fermions, correct? And there are only two spin moieties, half-spin and integer-spin, correct? And the integer spin particles are the bosons, which are in the other moiety from the fermion field we are discussing, correct? And this means that the most important difference between the two biggest moieties of particles, one of which represents classical "matter" and the other of which represents classical "energy," is spin, correct? And spin is, not merely affected by but entirely due to Lorentz symmetry, correct? So how can you claim the Dirac field is not relativistic when its most basic character, its spin is determined by the symmetry of special relativity, the Lorentz symmetry?

Biscuits 'n' gravy with scrambled egg beaters and turkey sausage patties.

I protest; this is not a "quick physics question" but one of the most profound subjects in physics today! Not that that's bad.

ajb, pretty sure this one predates the Landscape. I think the documentary's talking just about straight M theory, and cut it very short; perhaps they didn't even talk about what the string theories are that make the parts of it we've figured out up, just did a handwave like many such programs do, and went on to the ekpyrotic hypothesis which was what they really wanted to talk about. (And of course, you're absolutely correct, it is, in fact, the ekpyrotic hypothesis they're talking about. I have the impression it's the main part of the theory.) pyroglycerine, ajb is too modern for your documentary; he knows too much! Your program covered a very narrow piece of current cosmology, a hypothesis that has been put forward by a small faction. However, there is some evidence to indicate that they may be correct, but only looking at things from one very narrow perspective; their idea is likely to actually be one among many explanations, all correct, just as (for example) both the field and particle descriptions of elementary physics are two facets of the same truth. Just at the moment, however, cosmology has looked away from this hypothesis and is looking at data that is emerging from the Sloan Digital Sky Survey, in a program called "BOSS." I suspect we'll see the ekpyrotic hypothesis again, but at this point most cosmologists and astrophysicists are looking at this emerging data source since it is pretty much fountaining new data forth. Oooohhhh, shiny.

I'm going to make my guess that it's a reflection from a polished rock. I think I saw someone say there was a picture from a different perspective, which indicates a different location on the CCD; and it's in the same location against the background; that would rule out hot pixels except as the most astronomical coincidence. That is assuming the statement that there's more than one picture shown in that article is correct; it may not be. I haven't checked; I'm taking LaurieAG's word for it.

No. That's the preliminaries. We've never talked deeply about this stuff before so I don't know how to gauge your experience. I think we agree as far as that, remembering my mistake confusing the Ricci and Einstein tensors, and that you'll agree to what you see there so far. Except for the part about relativity and the Dirac field; I think we need to thrash that out first. Maybe I've made a mistake there. If so there's no point in going on; that's the mistake, I learned something, and since my assertion is based on it, obviously my assertion was wrong. This is why I'm being so finicky.

Post 75, please?

Sounds about right to me, imatfaal. I thought up an explanation for the flames, it's just a guess but unless it's some sort of hybrid thing this explains them: they're accelerating an object to hypersonic velocity in a tube; the gas law says the air in that tube is gonna get very hot, and if the projectile is supersonic the air can't move out of the way. At hypersonic velocity, I bet it might even get plasmatized. Doesn't that make sense?

You're talking about the math. The derivation of the mathematics is not the definition of the physical behavior. I'm talking about the field. And I'm talking about relativity and spin. You can't have a spin 1/2 particle/field without defining spin, and you can't have spin without relativity. Simple as that. And I'm still waiting for what's wrong with post 75. (Sorry for my mistake.)

My mistake, post 75. Since you've mentioned the Dirac field at the end of your last two posts, and still appear to feel that the Dirac field is not Lorentz symmetric, I will remind you that spin is based on the Lorentz symmetry, and for the Dirac field to be non-relativistic, it must, therefore, according to you, not have a spin. I don't think you've thought this all the way through. Edited to add, for the benefit of observers: spin is due to the fact that you cannot replace two successive Lorentz boosts with a single one; if you do, you must add a rotation. This is a consequence of the Lorentz symmetry. And that rotation is spin angular momentum. Since the very definition of the Dirac field is that it has spin 1/2, as opposed to the boson or Bose-Einstein field which has unitary spin, special relativity enters firmly into both the Fermi-Dirac and Bose-Einstein fields at their very most basic definition. It is not escapable by any trickery at all.