Ask a physicist anything. (7)

[GrowingSmaller]

Is there interference from virtual particles (if I have it right: popping into the world from nothingness, and then disappearing again) in collider observations?

 

[Chalnoth]

Is there interference from virtual particles (if I have it right: popping into the world from nothingness, and then disappearing again) in collider observations?

I don't know what you mean "interference", but virtual particles are fundamental to our understanding of the behavior of these collisions. When we calculate a collision, we compute a tremendous number of virtual particles being produced and destroyed in that collision.

 

[GrowingSmaller]

What I meant by interference is that I would have thought that the collisions would have taken place in a near vaccuum (except fot the particles wanted on the collision). But you can't create a vaccuum as there will always be virtual particles, hence they would be "interference" or "noise" when e.g. a proton (or whatever) collided with virtuals instead of the intended particles.

 

[gattaca]

Ask a physicist anything

what are the benefits of global warming to life on earth?

 

[mzungu]

what are the benefits of global warming to life on earth?

Increase of CO2 benefits plant life but not in areas where droughts become the norm. Tropical areas stand to benefit the most. However animals that need calcium (Sea creatures) for their shells or base structures like corals are adversely effected due to CO2 increasing the acidity of sea water and thus impeding calcium deposit growth in the said creatures.

 

[Chalnoth]

What I meant by interference is that I would have thought that the collisions would have taken place in a near vaccuum (except fot the particles wanted on the collision). But you can't create a vaccuum as there will always be virtual particles, hence they would be "interference" or "noise" when e.g. a proton (or whatever) collided with virtuals instead of the intended particles.

I don't think that's actually possible. Pretty sure that conservation laws prevent any sort of destructive collision with virtual particles. Basically, virtual particles that pop in and out of the vacuum conserve energy over long timescales. But a collision would require a significant expenditure of energy.

 

[Chalnoth]

what are the benefits of global warming to life on earth?

In the short term, between slim and none. The problem is that life on Earth is adapted to current conditions, and so the changes due to global warming just put pressure on basically everything alive. This includes plants, because the other effects of global warming typically put more pressure on plant populations than the small increase in growth due to CO2.

Now, granted, on long time scales, life will adapt. But many species will just go extinct in the interim (and we are already in the middle of one of the largest mass extinctions in Earth's history).

 

[pgp_protector]

In the short term, between slim and none. The problem is that life on Earth is adapted to current conditions, and so the changes due to global warming just put pressure on basically everything alive. This includes plants, because the other effects of global warming typically put more pressure on plant populations than the small increase in growth due to CO2.

Now, granted, on long time scales, life will adapt. But many species will just go extinct in the interim (and we are already in the middle of one of the largest mass extinctions in Earth's history).

hasn't something like 99% of all life on this planet already gone extinct?

 

[Chalnoth]

hasn't something like 99% of all life on this planet already gone extinct?

I don't think it's that much. Not yet anyway. At least not during the current extinction event.

 

[Orogeny]

I don't think it's that much. Not yet anyway. At least not during the current extinction event.

I think he meant 'over the history of the earth, over 99% of species that have existed no longer do'. Which is probably true.

 

[Chalnoth]

I think he meant 'over the history of the earth, over 99% of species that have existed no longer do'. Which is probably true.

Oh, yeah, that's definitely true. Well over 99%.

 

[Wiccan_Child]

Oh, yeah, that's definitely true. Well over 99%.

Well over 99%? There's only so many

 

[Nabobalis]

Well over 99%? There's only so many

Unless you use the Star Trek Warp scale

 

[Wiccan_Child]

Unless you use the Star Trek Warp scale

True - and I refuse to acknowledge that Warp Factor 10 and its hyperevolution witchery!

 

[Nabobalis]

True - and I refuse to acknowledge that Warp Factor 10 and its hyperevolution witchery!

Yeah that is a stretch even by Star Trek standards.

 

[Zippy the Wonderslug]

Why is that, to this current day, our methods of putting out disaster fires are still so very crude?

Is there no research funding at all into this?

Is water, halon, sky jell-o, and setting a fire somewhere else really the only best possible solutions?

 

[Wiccan_Child]

Why is that, to this current day, our methods of putting out disaster fires are still so very crude?

I wouldn't say its crude. In a sufficiently industrialised area (e.g., London), fires are relatively rare - concrete and steel don't tend to combust all that well. And even when they do, we can quickly and efficiently extinguish the flames once the fire brigade gets there.

The tricky part is controlling natural fires, such as flash fires in the outback of Australia.

Is there no research funding at all into this?

Is water, halon, sky jell-o, and setting a fire somewhere else really the only best possible solutions?

Can you think of anything else? We need to a) starve the fire of oxygen, b) prevent its heat and flame from spreading, and c) evacuate any and all people in the vicinity. Water is cheap and abundant does the first two quite nicely for all but the biggest of fires - and in that case we use something artificial and industrial to smother the flames.

So, there's not a lot of room for improvement. We can decrease response times, increase the 'fire-retardant' ability of whatever substance we douse the flames with, but as for techniques, we're pretty much there.

Unless you can build a sonic weapon to snuff the flames out en masse at a distance

 

[Chalnoth]

Can you think of anything else? We need to a) starve the fire of oxygen, b) prevent its heat and flame from spreading, and c) evacuate any and all people in the vicinity. Water is cheap and abundant does the first two quite nicely for all but the biggest of fires - and in that case we use something artificial and industrial to smother the flames.

So, there's not a lot of room for improvement. We can decrease response times, increase the 'fire-retardant' ability of whatever substance we douse the flames with, but as for techniques, we're pretty much there.

There's also the point to be made that water has extremely minimal environmental impact. More sophisticated fire dousing materials are highly unlikely to have anywhere nearly as low an impact.

Unless you can build a sonic weapon to snuff the flames out en masse at a distance

I do wonder if that's possible. Would be very cool if it were!

 

[Orogeny]

Jet Engine Fire Extinguisher Does The Job - Geekologie

 

[mzungu]

Jet Engine Fire Extinguisher Does The Job - Geekologie

Or you could put out the fire with Gasoline:
Moonlight - "Putting Out Fire With Gasoline" - YouTube