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Antihydrogen Trapped For 1000 Seconds

technologyreview.com

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Re: Antihydrogen Trapped For 1000 Seconds

#71

Post by othermaciej »

anigbrowl wrote: post #59
martinkallstrom wrote: post #27

$100 says antimatter is also attracted by gravity. Anything else would be too cool for school.

I'm with you on this one. If antimatter was just backwards everything then there'd be large conspicuous clusters of the stuff all over the cosmos because ordinary matter would be repelling it instead of annihilating it. While there does seem to be a lot of dark matter out there, if it were actually antimatter and had opposite gravity to normal matter one would imagine there would be a huge discrepancy between cosmolo…

We know two things about dark matter: - It doesn't interact electromagnetically. - It does interact gravitationally and produces extra gravitational attraction beyond the electromagnetically interacting matter we know about. - It is dispersed throughout galaxies.

The first property rules out baryonic antimatter as dark matter, since that would interact electromagnetically. The last two properties rule out anything that has a repulsive gravitational interaction as dark matter.

Re: Antihydrogen Trapped For 1000 Seconds

#73

Post by martinkallstrom »

enko wrote: post #53
natep wrote: post #52

Earlier quoted context omitted.

Doesn't look like your odds are good (consensus atm is there's no theoretical basis): http://www.reddit.com/r/askscience/comments/h28sd/is_there_a...

Well, let's see what the data says. I confess I want the universe to surprise and confound. I want the theories to be wrong, I want reality to be stranger than fiction. That would be awesome! Or I am wrong, in which case I'll happily pay out[1]. I'm a layman, as if that wasn't obvious, and it will be a much-needed physics lesson. Win-win. [1] If in Australia, payout will take the form of alcohol credits at an establi…

I want the theories to be wrong too, it's just that I'm a sceptic in this case simply because of the utter awesomness that would be the result.

I will happily spend more than $100 just on delivery if that is required to make a payout in liquor (local Swedish flavors) across the world. Crisp paper is fully acceptable as well :)

Doubt we will ever settle this though... I have painfully little faith in scientific breakthroughs.

Re: Antihydrogen Trapped For 1000 Seconds

#75

Post by Cushman »

kijinbear wrote: post #42
jwuphysics wrote: post #31

Earlier quoted context omitted.

If you were holding onto a chunk of antimatter you would probably be missing a hand.

Not if you're holding onto it using a magnetic field, or any other method that doesn't involve direct contact.

Is there any conceivable way to make such a system fail-safe?

Re: Antihydrogen Trapped For 1000 Seconds

#76

Post by Tuna-Fish »

ljf wrote: post #63

So who is bootstrapping the first startup right now to make hoverboards?

Assuming 1kg of antimatter can be used to hover 1kg of matter and that your hoverboard could carry 80kg, should it's containment fail, it would detonate with the force of 3.4 gigatons of tnt. That's roughly equivalent with the entire present nuclear arsenal of the united states, and would cause 3rd degree burns out of direct thermal radiation over 300 kilometers away.

So, umm, no.

Re: Antihydrogen Trapped For 1000 Seconds

#77

Post by Fargren »

enko wrote: post #53
natep wrote: post #52

Earlier quoted context omitted.

Doesn't look like your odds are good (consensus atm is there's no theoretical basis): http://www.reddit.com/r/askscience/comments/h28sd/is_there_a...

Well, let's see what the data says. I confess I want the universe to surprise and confound. I want the theories to be wrong, I want reality to be stranger than fiction. That would be awesome! Or I am wrong, in which case I'll happily pay out[1]. I'm a layman, as if that wasn't obvious, and it will be a much-needed physics lesson. Win-win. [1] If in Australia, payout will take the form of alcohol credits at an establi…

Well, it would be really cool and confounding if gravity made antimatter move sideways. But I don't think that's likely.

Re: Antihydrogen Trapped For 1000 Seconds

#78

Post by qntm »

natep wrote: post #52
enko wrote: post #51

Earlier quoted context omitted.

Fuck it, you're on. $100. I want to believe ...

Doesn't look like your odds are good (consensus atm is there's no theoretical basis): http://www.reddit.com/r/askscience/comments/h28sd/is_there_a...

That reddit post (and admittedly it is just a reddit post) actually says the opposite: there is no theoretical basis for antimatter not to behave exactly like regular matter in the presence of a gravitational field.

The null hypothesis (and, in the absence of any strong evidence to the contrary, the stronger hypothesis) is that antimatter and matter respond to gravity in exactly the same way.

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