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Physicists Turn Pull Into Push

samzenpus posted about a year and a half ago | from the push-me-pull-you dept.

Science 60

sciencehabit writes "It's textbook physics: An electric charge near the surface of a material gets pulled toward the surface. However, if the charge is spread out into the right shape and moves fast enough, that attraction becomes a repulsion, one physicist calculates. The odd finding could help physicists avoid unexpected effects when guiding beams of particles such as electrons."

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Repulsion Engines Online (3, Interesting)

lawnboy5-O (772026) | about a year and a half ago | (#42246855)

Make it so!

Re:Repulsion Engines Online (1)

earls (1367951) | about a year and a half ago | (#42247109)

Amen. Antigravity, finally.

Re:Repulsion Engines Online (4, Insightful)

Tough Love (215404) | about a year and a half ago | (#42247145)

If it works, it's antigravity just as much as a table leg is. In that sense, we have already had antigravity for some time. What you really meant to say is: land speeder, finally.

Re:Repulsion Engines Online (0)

Anonymous Coward | about a year and a half ago | (#42248049)

He wanted a hoverboard instead, helluva lot more convenient.

Re:Repulsion Engines Online (1)

tepples (727027) | about a year and a half ago | (#42248135)

He wanted a hoverboard instead, helluva lot more convenient.

Not over water, it isn't, unless you've got power [youtube.com] .

Re:Repulsion Engines Online (0)

Anonymous Coward | about a year and a half ago | (#42248719)

POOWWWAAAA

Bleh

Re:Repulsion Engines Online (1)

able1234au (995975) | about a year and a half ago | (#42247335)

Where's my tractor beam?

Re:Repulsion Engines Online (0)

Anonymous Coward | about a year and a half ago | (#42253435)

Probably somewhere near your tractor (hiding)

They could have just asked any geek (2, Funny)

Anonymous Coward | about a year and a half ago | (#42246865)

They seem to have that repulsion charge with girls.

Re:They could have just asked any geek (5, Funny)

Anonymous Coward | about a year and a half ago | (#42246911)

So you are saying that if a geek guy stops and listens to a girl, that she'll find him attractive?

Re:They could have just asked any geek (1)

OneAhead (1495535) | about a year and a half ago | (#42247067)

Well played sir or madam. Very well played.

Re:They could have just asked any geek (2)

somersault (912633) | about a year and a half ago | (#42247105)

I have data points that indicate this to be correct at least some of the time. There may be just a little more to it of course, but I'm sure future physics papers will give us some more hints.

Re:They could have just asked any geek (3, Funny)

besalope (1186101) | about a year and a half ago | (#42247583)

I have data points that indicate this to be correct at least some of the time. There may be just a little more to it of course, but I'm sure future physics papers will give us some more hints.

Pretty sure those are just outliers. Are you sure p from your dataset is remotely close to 0.05?

Re:They could have just asked any geek (2)

somersault (912633) | about a year and a half ago | (#42248956)

Only one of them was into that type of thing, so we'll never know.

Re:They could have just asked any geek (1)

MightyYar (622222) | about a year and a half ago | (#42246989)

That wears off around 30 or so...

Re:They could have just asked any geek (0)

Anonymous Coward | about a year and a half ago | (#42247093)

That wears off around 30 or so...

Yeah that is about when the average female starts to think a solid mate who will provide for her and care about her, is a tad more important than playing idiotic mindgames, teasing, and whoring for attention. Eventually they figure out that emotionally or physically abusive "bad boys" were a bad choice and that no good man will want them unless they get their values straightened out.

Course lots of women never figure that out. They wind up bitter and angry, with the attention span of a two-year-old, soon as the beauty fades. You can usually find those wherever there are waitstaff, impatiently demanding a lot more assistance than they really need, complaining all the while, hoping and praying the server will lose his cool and give them something to bitch to management about, for this type of person loves to abuse a captive audience.

Re:They could have just asked any geek (5, Insightful)

somersault (912633) | about a year and a half ago | (#42247127)

Yeah that is about when the average female starts to think a solid mate who will provide for her and care about her, is a tad more important than playing idiotic mindgames, teasing, and whoring for attention

Counter-point: it's also when your average geek has settled into a well paying job/career.

Re:They could have just asked any geek (3, Funny)

I Mean, What (2778851) | about a year and a half ago | (#42247591)

Wait, who's bitter and angry?

Re:They could have just asked any geek (0)

Anonymous Coward | about a year and a half ago | (#42253753)

It's actually above average(in terms of intelligence) females who understand this. However many of them are what most males would consider average in terms of looks but meh, when you have a partner who is also your friend, looks can come a bit down the list, but only a bit. A poor personality can degrade a hot woman's appeal quite a bit.

The rest I agree with as my partner has seen some of her friends follow that track (ie hot chick gets all attention, plays around, acts the tease, personality is stunted, ends up as either a hooker or doing pr0n etc etc). Seen it happen from the other side as I've made freinds with a few bad-boy cast-offs.

So altho someone below me got modded funny, that really is how it goes for some people, but hey, I got mine and that's just their tough luck, regardless of gender =D

Re:They could have just asked any geek (3, Insightful)

Nerdfest (867930) | about a year and a half ago | (#42247339)

A more jaded person would say it wears off around $100K or so.

Other applications (1)

Anonymous Coward | about a year and a half ago | (#42246899)

How long till we can turn this technology into space ship energy shields? I'm sure they'd be handy with all the space junk we've created...

Re:Other applications (1)

Anonymous Coward | about a year and a half ago | (#42247115)

If you ever need to repel very specifically shaped/timed and energy pulses of charged particles, it would be perfect for a space craft if you don't mind other charged particles still being attracted and it doing nothing for neutral objects.

Great explanations (4, Funny)

jez9999 (618189) | about a year and a half ago | (#42246903)

It's textbook physics: An electric charge near the surface of a material gets pulled toward the surface. However, if the charge is spread out into the right shape and moves fast enough, that attraction becomes a repulsion, one physicist calculates.

This finally explains so much about women's behaviour towards me.

Re:Great explanations (0)

Anonymous Coward | about a year and a half ago | (#42247231)

its all about the shape and velocity, then. No surprise if small , fast ejaculators repel women

Re:Great explanations (2)

Impy the Impiuos Imp (442658) | about a year and a half ago | (#42247417)

Even quoting to her how Tony Stark's repulsor rays work?

ION engines? (0)

colin_faber (1083673) | about a year and a half ago | (#42246925)

This sounds very similar to the idea behind ion engines. It's interesting and I wonder if this discovery was something new, or something finally explained.

Re:ION engines? (4, Informative)

Anonymous Coward | about a year and a half ago | (#42246997)

It isn't like an ion engine at all. What they are saying is that electrostatic induction [wikipedia.org] is not always attractive but it takes very specific conditions to make it repulsive. An ion engine doesn't use induction. Induction is the force between a neutrally charged object and a charged object.

Re:ION engines? (0)

Anonymous Coward | about a year and a half ago | (#42247371)

> What they are saying is that electrostatic induction

No, there's no "electrostatic" about it. It's moving charges. Holly crap, moving charges interact with one another! Well yeah...

Re:ION engines? (1)

Anonymous Coward | about a year and a half ago | (#42247065)

Ion drives require no such trickery; positive ions are accelerated by the electrical field between a positive and negative grid with enough energy to carry them clear of the negative grid once they've passed through it. There's no attraction turning into repulsion or vice versa, just the basic physics that you learnt at school.

For the door that you push instead of pull (1)

Anonymous Coward | about a year and a half ago | (#42246937)

Now you won't look so bad.

They should work on the reverse (2)

Spy Handler (822350) | about a year and a half ago | (#42246985)

we already know lots of ways to push things... jet engines to push planes, gunpowder to push bullets out of a gun, etc.

What we need is a way to PULL things, so we can make a tractor beam. So far we got... nothing.

Re:They should work on the reverse (4, Funny)

multiben (1916126) | about a year and a half ago | (#42247069)

Sure we do. Rope!

Re:They should work on the reverse (5, Funny)

Tough Love (215404) | about a year and a half ago | (#42247191)

Why didn't I think of that? A matter beam. Brilliant.

Re:They should work on the reverse (4, Funny)

Carewolf (581105) | about a year and a half ago | (#42247421)

All personal at battle stations: Fire the matter beam!!

*poke*

Re:They should work on the reverse (0)

Anonymous Coward | about a year and a half ago | (#42248015)

New York City!

Get a Matter Beam!

It's obvious when you think about it (1)

beer_maker (263112) | about a year and a half ago | (#42251765)

I was a starship trooper till I took a matter beam to the knee ...

Re:They should work on the reverse (1)

jeffb (2.718) (1189693) | about a year and a half ago | (#42252699)

This is my new favorite euphemism of the day.

Re:They should work on the reverse (0)

Anonymous Coward | about a year and a half ago | (#42247151)

So we need to invent an engine that moves the universe backwards.

Re:They should work on the reverse (0)

Anonymous Coward | about a year and a half ago | (#42249856)

We have magnets, just no way to pull matter in general.

This is not news (1)

G3ckoG33k (647276) | about a year and a half ago | (#42247165)

I woke up one morning and the attraction I had felt the night before had turned into repulsion.

So what is new? That it is on Slashdot?

Re:This is not news (1)

Tablizer (95088) | about a year and a half ago | (#42247311)

And it had nothing to do with those 8 beers you had?

Re: (0)

Anonymous Coward | about a year and a half ago | (#42247331)

Did it spread into the right shape and move fast enough?

Brazilians did too (0)

Anonymous Coward | about a year and a half ago | (#42247169)

Tell a brasilario to push something and see what happens

theoretical bs (1)

illestov (945762) | about a year and a half ago | (#42247459)

sigh.. another ridiculous claim from some random physicist grabs the headlines because it "violates the laws of physics"

And if a charge moves through the glass faster than light can, it creates a shockwave of light

Re:theoretical bs (4, Informative)

Chuckstar (799005) | about a year and a half ago | (#42247533)

Nothing in the article violates the laws of physics. It's merely a question of who did the math more accurately for the specific case of the given arrangement of electrons.

Cherenkov radiation is a well understood phenomenon. What you are missing is that the cosmic speed limit is the speed of light in a vacuum. Where the speed of light is slower (i.e. glass), it does not violate the laws of physics for a particle to move faster than that speed. In the given example: the electrons move faster in glass than light moves in glass, but still slower than light moves in a vacuum.

Re:theoretical bs (1)

illestov (945762) | about a year and a half ago | (#42247745)

For Cherenkov Radioation , doesn't the charged particle have to move through a dialectic medium, not above its surface?

Re:theoretical bs (1)

Anonymous Coward | about a year and a half ago | (#42248653)

Yes, but in this case the particles moving in the glass are being forced by the passing electron outside it.

Re:theoretical bs (2)

Muad'Dave (255648) | about a year and a half ago | (#42251957)

For Cherenkov Radioation , doesn't the charged particle have to move through a dialectic medium, not above its surface?

I don't think the charges use spirit guides to exchange logical arguments to resolve disagreements [wikipedia.org] .

Re:theoretical bs (-1)

Anonymous Coward | about a year and a half ago | (#42249414)

" It's merely a question of who did the math more accurately for the specific case of the given arrangement of electrons."

This work has been already done by Larry Spring.
http://www.larryspring.com/magnespheres.html

I been nipping at slashdot ass for many years (since mid 90's) about Larry Spring's Magnespheres..

Prior to this I only knew
traditional high school physics
Then USAF electronics
Then one day I found a book (giant paperback one of several in a series of like 3 and 4 or something) which said that, a crystal in copper box, which is sealed to become a pure vacuum out in space, with solar panel trickle, and antenna to beam energy to recktenna down on earth, I learned this from a book on CRYSTALS back in the 1980's. The danger then is as it is now, getting in the path of that beam. Hint it ain't the green ray! or some channeled crap from Michael.

In the 1990's at a Tesla meeting in San Francisco, I picked up his book called "Common Sense Physics"
I've ran off that code/belief/math ever since ^^ all the way up to recently when studying the UN's climategate, by actually learning something more about geoengineering, cloud seeding, and the HF UHF microwave haarp technology stations basically shoving insane amounts of RF up into our sky, creating plasma mirrors, and many others in the sky from dutchsince.

So at this point I am of the opinion of okay whatever, I don't give a shit what the fuck some physicst wants to call his shit, all I am saying is don't be so quick to jump on the UN/IPCC global warming crap, they're the ones CAUSING THE WARMING with this GeoEngineering shit.

This leaves me in a state of being PISSED off at being lied to. Fuck the Greens, Fuck Carbon Tax, Fuck the IPCC, fuck the UN, fuck NATO, fuck all these fucking liars and oath breaking sellout pieces of shit that support them like ICLEI.

And fuck the slashdot trolls that keep pushing my shit down, you little fucking pricks are getting a lot more than you can comprehend by shutting my word down..

It's bitter out here, add the fucking spying, and it's almost time to say fuck it, go fucking prepare for TEOTWAWKI.

A special sliver' y fucking baseball bat up the ass of those who know exactly that which I speak, yet sit there doing nothing of laughing as I flail in the wind. Add in this oath breaking shit about changing the spirit of words or using specific words which if not spoken, then allow for plausable deniability, e.g. we don't have "ChemTrails" we have "Aerial Spraying", or "GeoEngineering", so when asked these cocksuckers FUCKING LIED about it, oh no we're not doing that., when in fact the fuckers have local county contracts for exactly what the fuck we were complaining about!!! (we just used the wrong WORDS) All that RF in the sky, it that isn't even talked about, the shit's invisible (just like your electronic vote.) You little pricks can keep justice from the public by writing law in a language that has to be translated (lawyers) to plain fucking english. The next mistake is going to be pissing everyone off to the point they are screaming for your lying murderous oath breaking treasonous DEATH, and at that point in time, I have no reason to protect any elected official who is an oath breaker from their just and GOD provided reward.. I may sound scater brained when talking about this shit, but once you grasp the SIZE you will be scaterbrain too

Re:theoretical bs (4, Informative)

History's Coming To (1059484) | about a year and a half ago | (#42247625)

Nope, they're referring to Cerenkov radiation [wikipedia.org] , it's a known effect and produces a very pretty blue light in nuclear reactors. It occurs when the phase velocity travels faster than the speed of light in that medium which is all fine and dandy and breaks no rules at all.

Re:theoretical bs (0)

Anonymous Coward | about a year and a half ago | (#42251483)

A very pretty blue light indeed, that if you find yourself directly observing and appreciating its prettiness it probably also means radiation poisoning of some serious kind

Re:theoretical bs (2)

Muad'Dave (255648) | about a year and a half ago | (#42252055)

Not in the least. I've been in the 'core' of a couple of small research-grade swimming pool [wikipedia.org] reactors (including this one [uvamagazine.org] ), and you can see the blue light [google.com] quite well and with no danger from radiation.

It's Mega Maid... (-1)

Anonymous Coward | about a year and a half ago | (#42247823)

It's Mega Maid. She's gone from suck to blow. (funny how often this joke applies to stories here lately)

Mr Checkov Deflectors on full! (0)

Anonymous Coward | about a year and a half ago | (#42248007)

Mr Checkov Deflectors on full!

Re:Mr Checkov Deflectors on full! (0)

Anonymous Coward | about a year and a half ago | (#42256147)

Mr. Checkov alright. He's right here http://science.slashdot.org/comments.pl?sid=3307513&cid=42247625 [slashdot.org] saying "it was inwented in Russia" since it's named after Russian scientist Pavel Alekseyevich Cherenkov

But how the fuck does a flywheel lose its weight? (-1)

Anonymous Coward | about a year and a half ago | (#42248701)

When this faggot does this shit?

http://www.youtube.com/watch?v=MHlAJ7vySC8

pull/push (0)

Anonymous Coward | about a year and a half ago | (#42249600)

I bet they got the idea from Phoebe Buffay:
http://www.youtube.com/watch?feature=player_detailpage&v=pr4UkL-TcHk#t=61s

All you need to do is... (1)

jeffb (2.718) (1189693) | about a year and a half ago | (#42252773)

...keep your velocity higher than 80% or so of c. If your velocity drops below the velocity of light in the repelling surface, the Cherenkov radiation goes away, there's no more repulsion, and you land on the surface cruising at .5c or so. Hope the tires on your landing gear are properly inflated.

Actually, now that I think about it, you'd probably get plenty of backup lift from the relativistic plasma formerly constituting the repulsive surface and the bottom of your vehicle. I withdraw my objection.

Re:All you need to do is... (0)

Anonymous Coward | about a year and a half ago | (#42255099)

Tsk! It's not 80% of c - I think you'll find it's 88mph that you're thinking of... There was a very clear documentary on this subject just a few years ago.

"Ladies & Gentlemen - What if I told you... (0)

Anonymous Coward | about a year and a half ago | (#42256189)

... That in just a few short years, Your automobile won't even have to touch the ground, at all! With Stark Rubidic Reversion Technology? You'll be able to do, just that..." - Howard Stark, Captain America

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