Can we power a light bulb with positrons?

[cragar]

would we need anti-tungsten to do it.

 

[mgb_phys]

Yes and anti-copper, and anti whatever gas is in the lightbulb

 

[cragar]

i see

 

[jtbell]

And anti-glass for the bulb, and anti-air outside the anti-glass, and anti-people to look at it...

 

[Kopachris]

Yes and anti-copper, and anti whatever gas is in the lightbulb

That would be anti-argon (and a little anti-nitrogen). We'd also need anti-silicon and anti-oxygen. I suppose we could suspend it magnetically so we wouldn't need anti-air.

 

[Santa1]

Wouldn't the positrons annihilating with electrons (or something else for that matter) produce "light"? Probably not visible, and\or lethal, but still I'd call it a lightbulb.

 

[mgb_phys]

Back to the OP's question.
Assuming you had the tungsten filament suspended somehow so that it didn't have to touch the seal at the base of the bulb and you had a perfect vacuum in the bulb so you didn't have to worry about gas molecules hitting the anti-tugsten.

Then, yes it would work perfectly normally and you wouldn't be able to tell that the photons emitted were from anti-matter

 

[Bob S]

RE positrons in our light bulbs
Assuming you had the anti-tungsten filament suspended somehow so that it didn't have to touch the seal at the base of the bulb and you had a perfect vacuum in the bulb so you didn't have to worry about gas molecules hitting the anti-tugsten filament.

Then, yes it would work perfectly normally and you wouldn't be able to tell that the photons emitted were from anti-matter

This may be slightly off the subject, but how would we determine whether some (half?) of the millions of galaxies we see through the Sloan Digital Sky Survey and other telescopes were made of antimatter? Most of the photons we see from other galaxies are from atomic transitions (e.g.; Balmer series in hydrogen) and not from beta decay, so helicity is out.

 

[mgb_phys]

how would we determine whether some (half?) of the millions of galaxies we see through the Sloan Digital Sky Survey and other telescopes were made of antimatter?

You can't - the only reason to think they aren't is that you don't see the x-rays from where their anti-interstellar medium meets out interstellar medium.