Gregory Benford
Professor
Plasma Physics and Astrophysics
(949) 824-5147
Professor Benford earned his Ph.D. from the University of California, San Diego in 1967. He is a member of Phi Beta Kappa, a Woodrow Wilson Fellow, and a consultant for NASA.
This program unites theoretical studies with a parallel experimental program in radiation processes of relativistic electron streams in plasma. Experiments use intense relativistic beams (10 kAmp, 700 keV) propagating in helium plasma. Microwave and atomic spectral (Stark shift) diagnostics measure emission and the underlying turbulent fields. The group also studies the practical methods of high-power microwave emission. Turbulence levels are high, with electric field energy densities comparable with the total thermal energy of the background plasma. Such strong fields demand new theory and sophisticated diagnostics, with fast time resolution (less than ten nanoseconds). This is a new regime -- "superstrong" turbulence -- with statistical properties just being explored.
These experiments and coupled theory apply to galactic jets, quasars, and pulsars. Emission by scattering of energetic electrons from plasma turbulence (which the beams themselves produce) can be much more powerful that the familiar single-particle processes such as synchrotron radiation. The extreme variability of quasars recently discovered in radio and optics may arise from such processes. Calculations of expected power and spectra imply that quasars could be powered by flows with less total energy than formerly expected. Much work needs to be done in relating these new, collective radiation mechanisms with both astrophysical and laboratory observations.
Teaching areas include general properties of strong turbulence and radiation, both in experiment and theory. Astrophysical applications of these fundamental areas are also of interest, such as the brilliant radio features (arcs, filaments, threads) recently found at our own galactic center, and their possible links with hypothesized black holes there.
Representative Publications
Coherent Radiation from Energetic Electron Streams via Collisionless Bremmstrahlung in Electrical Plasma Turbulence, (with J. C. Weatherall), Astrophys. J. 378, 543 (1991).
Collective Emission from Rapidly Variable Quasars, Astrophys. J. 391, L59 (1992).
Electron Beam Radiation by Collective Compton Boosting of Strong Turbulence, (with J.C. Weatherall), Phys. Fluids B 4 (12) 4111 (1992).
Collective Radiation from Jets, Proceedings of the 7th IAP Astrophys. Meeting, Extragalactic Radio Sources from Beams to Jets, Paris, July 2-5 (1991).
Statistics of Strongly Turbulent Electric Fields, (with X.-L. Zhai), Phys. Fluids B 5 (6) 1914 (1993).
GREGORY BENFORD
Doing Alien
I REMEMBER HOW MITCHELL was putting the moves on some major league pussy when the news about the aliens came in.
That Mitchell, he stopped in mid-line and cocked his big square head and said kind of whispery, "Double dog damn." Then he went back to the little redhead he had settled onto the stool next to his, way down at the end of the mahogany bar at Nan's.
But I could tell he was distracted. He's the kind of fella always drawn to a touch of weirdness. At Mardi Gras he just loved the confusion, not being able to tell guys from gals, or who was what, the whole thing.
He left with the redhead before ten, which was pretty quick even for Mitchell. When he's headed for the sheets there isn't much can get in Mitchell's way. But he kept glancing over at the Alphas on the TV. Going out, he gave me the old salute and big smile but I could tell he was thinking off somewhere, not keeping his mind and his hands on the redhead. Which wasn't like him.
Mitchell's been my buddy since the earth's crust cooled off. I can read him pretty well. We graduated high school about the time the dinosaurs started up and went into farm equipment sales together when there were still a few nickels to make in that game. I've seen Mitchell bareass in the woods howling around a campfire, watched him pulling in six-foot tuna off the back of McKenzie's old boat, laughed when he was drunk up to his eyeballs with a big brassy broad on each arm and a shit ass happy grin. For sure I know him better than any of his goddamn two ex-wives or his three kids. None of them'd recognize him on the street, pretty near.
So when the Alphas showed up right here in Fairhope I could tell right away that Mitchell took it funny. These Alphas come in slick as you please, special escort in limos and all. They go down to the wharf and look at the big new Civic Center and all, but nobody has a dime's worth of idea what they're here for.
Neither does the escort. Two suits on every Alpha, dark glasses and shoulder-slung pistols and earplug radios and the like. You could see it plain, the way their tight mouths twitched. They dunno from sour owl shit what to expect next.
For sure nobody thought they'd go into Nan's. Just clank on in, look around, babble that babble to each other, plunk down on those chrome stools.
Then they order up. Mitchell and me, we was at the other end of the bar. The Alphas, they are ordering up and putting them down pretty quick. Nobody knows their chemistry but they must like something in gimlets and fireballs and twofers, cause they sure squirt them in quick.
Pretty soon there's a crowd around them. The suits stand stiff as boards, but the locals ooze around them, curious. The Alphas don't pay any attention. Maybe they're used to it or maybe they don't even know people are there unless they need something. Way they act, you could believe that.
But Mitchell, he keeps eyeing them. Tries to talk to them. They don't pay him no never mind. Buys one a drink, even, but the Alpha won't touch it.
I could see it got to him. Not the first day maybe or the second. By the third, though, he was acting funny. Studying them. The Alphas would show up at Nan's, suck in plenty of the sauce, then blow out of town in those limos.
News people around, crowds waiting to see them, the whole goddamn shooting match. Made Fairhope hell to get around in. I was gone three days to Birmingham on a commission job with International Harvester, so I didn't see what stared him on it. I come into town all busted out from chasing tail in Birmingham and first thing you know, phone rings and Mitchell wants help.
"I'm in that beat up shack back of Leroy's TV," he said.
"That place's no biggem a coffin and smells worse."
"They spruced it up since Briggs run that poker game in here."
"So who you pokin there now?"
"Fred, your dick fell off your I.Q. would be zero."
"That happen, what'd I need to think for?"
"Get your dumb ass over here."
So I did. Walk in on Mitchell in a chair, this brunette working on him. First I figured she was from over Bessie's, giving him a manicure with her kit all spread out. Turns out she's a makeup gal from clear over to New Orleans. Works Mardi Gras and like that.
Only she's not making Mitchell up to be a devil or in blackface or anything. This is serious. She's painting shellack all over him. He's already got a crust on him like dried mud in a hog wallow, only it's orange.
"Christ on a crutch," is all I can say.
"Mix me a bourbon and branch." Mitchell's voice came out muffled by all these pink pancake-size wattles on his throat, like some kind of rooster.
So I do. Only he doesn't like it, so he gets up and makes his own. "Got to add a twist sometimes," he says.
Mitchell was always picky about drinks. He used to make coffee for the boys, morning after a big carouse, and it had to be Colombian and ground just so and done up in this tricky filter rig he made himself out of tin sheeting.
That's how he was with this makeup girl, too. She layered on ridges of swarthy gum all down his arms, then shaped it with little whittling tools. She was sweating in that firebox shack. Mitchell was too under all the makeup.
I'm wondering what the hell, a
nd Mitchell says, "Go take a squint, see if they're in Nan's yet."
So I'm catching on. Mitchell's always had something working on the side, see, but he takes his time about letting on. Kind of subtle, too. When Mr. Tang moved into Fairhope with his factory, Mitchell was real respectful and polite and called him Poon for a year before that Tang caught on.
As I go out the shack and down the alley I see why he used that place. I angle across Simpson's parking lot and down by those big air conditioners and pop out on Ivy right next to Nan's. That way, none of the suits can see you coming. Slip in the side door and sure as God's got a beard, there's three Alphas. Got a crowd around them but the room is dead quiet. People just looking and wondering and the aliens drinking.
I'd heard that plenty of fastlane operators were trying to get information out of Alphas, seeing as they got all this technology. We didn't even see them coming, that's how good their stuff is.
First thing anybody knew, they were bellying up to Venus, this other planet out there. Covered in clouds, it was. Then the Alphas start to work on her. First thing you know, you can see those volcanoes and valleys.
Anybody who can clear up muggy air like that inside a week, you got to pay attention. Turned out that was just cleaning off the work bench. Next they spun a kind of magnetic rod, rammed it in at the pole, clean down into the core of the whole damn planet. Easy as sticking an ice pick through an apple. Only the ice pick was hollow and they sucked the liquid metal out of there. Up the rod like it was a straw, and out into space. To make those metal city kind of things, huge and all.
That's when people started getting really afraid. And some others got really interested. The way they figured, any little scrappy thing you got from an Alpha might just be a billion-buck trick.
That's the scoop I heard on CNN coming down from Birmingham, anyway. Now here was the whole circus in Fairhope, big as life and twice as ugly. Snoops with those directional microphones. Cameras in the backs of vans, shooting out through dark windows. Guys in three-piece suits kind of casual slouched against the bar and trying to get an Alpha to notice them.
So back I go. Mitchell is getting some inflated bags stuck on him by the makeup girl. Bags all over his back and chest and neck even. He's all the Alpha colors now, from Georgia clay red here to sky blue there.
"Three of 'em sucking it up in there," I said.
"Holy shit, let's go," Mitchell croaks back at me. The girl had fitted him out with this voicebox thing, made him sound like a frog at the bottom of a rain barrel.
The girl pats him all over with that fine, rusty dust the Alphas are always shedding. She straightens the pouches so you can hardly see that his arms are too short for an Alpha.
"Let's make tracks," Mitchell says, and proceeds to do just that. Alpha tracks, fat and seven-toed.
We go across the parking lot, so the escorts can't see. In a minute we're in Nan's. The other Alphas don't take any notice of Mitchell but all the people do. They move out of the way fast and we parade in, me a little behind so it'll seem like I was just a tourist. Mitchell's got the Alpha shuffle down just right, to my eye.
Bold as brass, he sits down. The suits look at each other, dunno what to do. But they buy it, that Mitchell's one of them.
The Alphas still don't notice him. Bartender asks and Mitchell orders, making a kind of slithery noise.
He slurps down two drinks before anything happens. An Alpha makes a gesture with that nose thing of theirs and Mitchell does too. Then there's some more gesturing and they talk like wet things moving inside a bag.
I sit and listen but I can't make sense out of any of it. Mitchell seems to know what he's doing. He keeps it up for maybe five more minutes. I can see it's wearing on him. He gives me the signal.
I clear some space for him so he can get back up -- that crap he was wearing weighs real considerable. He gets up smooth and shuffles some and then we're out the door. Free and clean. We got back to the shack before we let go with the whooping and hollering.
We pull it off four more times in the next three weeks. Each time the Alphas take more notice of Mitchell. Hard to know what they think of him. The gift comes over from New Orleans and does him up, getting better each time. I keep an ear open for word on the street and it's all good.
Or seems so to me, anyway. Everybody thinks Mitchell's the real thing. Course that's people talking, not Alphas. After the fourth time I couldn't hold back any more. "You got some money angle on this, right?"
"Money?"
"What I want to know is, how you going to get anything out of them?"
"I'm not in for money."
"You figure maybe you can get one of those little tool kits they carry? They don't look hooked on real firm or anything."
Mitchell grinned. "Wouldn't try that, I was you. Fella in Cincinnati went to lift one, came up an arm short."
"Then what the hell you in for?"
Mitchell gave me this funny look. "Cause it's them." I blinked. "So goddamn what?"
"You don't get it, Fred. Thing about aliens is, they're alien." In his eyes there's this look. Like he was seeing something different, something important, something way bigger than Fairhope.
I couldn't make any more sense out of what he said after that. That's when I realized. Mitchell just wanted to be close to them, was all.
That pretty well took the wind out of my sails. I'd figured Mitchell was onto something for sure. I went with him one more time, that's all. And a few days later I heard that the same Alpha was coming back to Nan's every day, just sitting and waiting for more Alphas to come in, and hanging out with them when they did.
It went that way for a while and I was feeling pretty sour about it. I went on a carouse with the Perlotti brothers and had me a pretty fair time. Next morning I was lying in bed with a head that barely fit in the room and in walks Mitchell. "Heard you maybe needed some revivin' from last night."
He was grinning and I was glad to see him even if he did waste a slab of my time. We'd do little things like that for each other sometimes, bring a fells a drink or a hundred dollar bill when he was down and could sure use it. So I crawled up out of bed and pulled on some jeans and went into the kitchen.
Mitchell was filling a pot and popping open one of his Colombian coffee packs. I got some cups and we watched the water boil without saying anything. That's when it happened.
Mitchell was fooling with the coffee and I was still pretty bleary-eyed, so I'm not sure just exactly what I saw. Mitchell was stirring the coffee and he turned to me. "Ummm. Smell those enzymes."
He said it perfectly natural and I wouldn't have taken much notice of the funny word. I looked it up later at the library and it's a chemical term, I forget what it means. Mitchell would never have said something like that. And I wouldn't have given it any mind, except that just then his arm stuck a little farther out of the denim work shirt he had on. He has big arms and thick wrists. As the shirt slid up I saw the skin and curly hair and then something else.
At first I thought it was leather. Then it seemed like cloth, real old fabric, wrinkled and coarse. Mitchell turned further and looked at me and that's when I heard the sound of him moving. It was like dry leaves rustling. Old and blowing in a wind. In the next second I caught a whiff of it and the worse smell I ever knew came swarming up into my head and I finally really saw what the thing next to me was.
I don't want to describe that. It sent me banging back against the plywood wall of the kitchen and then out the door. The smell stayed with me somehow even in the open. I was off into the pines way back of my place before I knew it.
I had the shakes for hours. Made myself circle around for three miles. Got to my sister's place. Didn't tell her anything about it but I think she might of guessed. I was pale and woozy.
I got my truck and went off to Pensacola for a week. There was maybe some work there but it didn't pan out and I hadn't gone for that anyway.
I didn't go back into my place for another week. And I was real careful when I did
.
It was all picked up, neat as you please. Not a sign. Mitchell was a fine man but he would never have done that.
I stood in the kitchen and tried to work out what had happened, how it had been. Couldn't. There was that one second when I saw straight into whatever was there and being Mitchell, and that was all.
He had tried to blend in with them. And I'd helped him. So in some way maybe this was the reverse. Or a pay back, kind of. Or maybe a signal or something. No way to tell.
Only, you know what I think? I figure there isn't any Mitchell anymore. There's something else.
Now, could be there's still some Mitchell in there, only he can't get out. Or maybe that thing's Alpha for sure. I guess it could be something in between. Only thing I know is, it isn't anything I ever want to know.
Maybe it's something I can't know. Thing about aliens is, they're alien.
They say that one Alpha still hangs out at Nan's. I haven't been to check. I don't even walk down that part of town anymore.
< Converted by HTMLess v2.5 by Troglobyte/Darkness. Only Amiga... >
GREGORY BENFORD
THE FOURTH DIMENSION
Suppose that next to you, right now, a pale gray sphere appeared. It grew from baseball-sized to a diameter as big as you -- grainy, gray, cool to the touch -- then shrank to a point . . . and disappeared.
You would probably interpret it as a balloon blown up, then deflated. But where did the flat balloon go?
Or you could realize that you had been visited by a denizen of a higher dimension -- a four dimensional sphere, or hypersphere. In three dimensions, it looks like a sphere, the most perfect of figures, just as a sphere projected in two dimensions makes a circle. The fact that this isn't an everyday occurrence implies that travel between dimensions is uncommon, but not that it is illogical.
Probably you would not have thought of such ideas before 1884. That is due to the Reverend Edwin Abbott Abbott, M.A., D.D., headmaster of the City of London School.
Respected, well liked, he led a strictly regular life, as proper as a parallelogram. He had published quite a few conventional books with titles like Through Nature to Christ, Parables for Children and How to Tell the Parts of Speech. These did not prepare the world for his sudden excursion into the fantastic, in 1884. Beneath his exterior he was a bit odd, and his short novel Hatland has proved his only hedge against oblivion, an astonishingly prescient fantasy of mathematics.
Essays Page 1