Exciting new developments in nuclear power

[Cabal]

The laser system for the National Ignition Facility has been completed, albeit a little late:

http://www.physorg.com/news155846213.html

There's also a new reactor type being developed in Texas that can generate power while reducing the half-life of existing nuclear waste by transmutation.

http://physicsworld.com/cws/article/news/37903

Cool stuff!

 

[Split Rock]

The laser system for the National Ignition Facility has been completed, albeit a little late:

http://www.physorg.com/news155846213.html

There's also a new reactor type being developed in Texas that can generate power while reducing the half-life of existing nuclear waste by transmutation.

http://physicsworld.com/cws/article/news/37903

Cool stuff!

Yes, but will these Godless Mad Scientists create a Black Hole and get us all sucked up into it? The End of Days is nigh!

 

[Cabal]

Yes, but will these Godless Mad Scientists create a Black Hole and get us all sucked up into it? The End of Days is nigh!

Foolish religionite! We already have the LHC for that! MWAHAWHWAHAHAHAH

 

[Avatar]

It's all fun and games until you pass the event horizon...

 

[Hespera]

is a mini black hole heavy? would it sink to the center of the earth then start hollowing it out?

 

[Split Rock]

is a mini black hole heavy? would it sink to the center of the earth then start hollowing it out?

White dwarf or neutron star material would do so. I assume a black hole would have no problem passing right through the earth.

 

[Assyrian]

It's all fun and games until you pass the event horizon...

Which n..e....v......e........ r........... h............a..............p................p....................e........................n..................................s...

 

[sbvera13]

is a mini black hole heavy? would it sink to the center of the earth then start hollowing it out?

It'd swing wildly through the earth's center and gravity and back again, passing effortlessly through the Earths matter and eating up about it's diameter's worth as it went by- depending on how fast it was going, of course, and what it's actual mass is. When it's total mass exceeds the remaining total mass of the earth it'll start sucking everything up at once. Fun times!

 

[ranmaonehalf]

is a mini black hole heavy? would it sink to the center of the earth then start hollowing it out?

Silly, the earth is hollow already.

http://en.wikipedia.org/wiki/Hollow_earth_theory

 

[bigbadwilf]

I had a look at the article, and I think it's probably best to point out that it's still an experimental machine, rather than a power station yet.
As experiments go it is a big one though, right up with the the Large Hadrian Collider (that fires Roman Emperors at each other), and quite a step up from it's immediate predecessor, the Mega Amp Spherical Tokamak (MAST) project that has been running for about the last ten years.

The main real snag is that (according to my dad, who was one of the electronic engineers working on MAST) the thing will likely be run by high-energy physicists who don't really exist on the same mental plane as the rest of us.

 

[Cabal]

I had a look at the article, and I think it's probably best to point out that it's still an experimental machine, rather than a power station yet.
As experiments go it is a big one though, right up with the the Large Hadrian Collider (that fires Roman Emperors at each other), and quite a step up from it's immediate predecessor, the Mega Amp Spherical Tokamak (MAST) project that has been running for about the last ten years.

The main real snag is that (according to my dad, who was one of the electronic engineers working on MAST) the thing will likely be run by high-energy physicists who don't really exist on the same mental plane as the rest of us.

Fair points indeed - it'll be an interesting step forward nonetheless though. I'm curious though as to how it being run by high-energy physicists is a "snag" (not offended, just curious, seeing as your family has been involved with one of these things).

 

[sfs]

Fair points indeed - it'll be an interesting step forward nonetheless though. I'm curious though as to how it being run by high-energy physicists is a "snag" (not offended, just curious, seeing as your family has been involved with one of these things).

The standard comment about practical fusion power is that it's only twenty years away, and has been for the last fifty years. Unexpected difficulties have cropped up so many times that some caution is indeed in order.

As an ex-high-energy physicist, I'm also a little surprised that high-energy physicists would be heavily involved, since they have no particular expertise in either fusion or lasers.

 

[bigbadwilf]

Physicists, and in particular high-energy physicists are notorious for having enormous feature-creep in their experiments, and are usually bad at communicating the exact specifications for what they want.

It makes life "entertaining" for the engineers who are actually trying to build the thing, as they'd go away and change what exactly they wanted it to do and assume that it would, without telling the people who would have to redesign and/or rebuild it.

Plus, when you're getting that near to what was theoretical physics, you tend to start running into the Pauli Effect (http://en.wikipedia.org/wiki/Pauli_effect), which can prove problematic when you're dealing with very powerful lasers, insanely strong electromagnets and even high-end vaccum pumps.

 

[bigbadwilf]

As an ex-high-energy physicist, I'm also a little surprised that high-energy physicists would be heavily involved, since they have no particular expertise in either fusion or lasers.

It's certainly the case in the UK, where most of the serious toys are owned either by the UKAEA or the STFC, (sorry United Kingdom Atomic Energy Authority or the Science and Technology Facilities Council), the thing is that the two main UKAEA sites are within ten miles of the main STFC laboratory complex (one of them actually shares a fence with it) so there is a continual cross-pollination/inbreeding between the two.

 

[sfs]

It's certainly the case in the UK, where most of the serious toys are owned either by the UKAEA or the STFC, (sorry United Kingdom Atomic Energy Authority or the Science and Technology Facilities Council), the thing is that the two main UKAEA sites are within ten miles of the main STFC laboratory complex (one of them actually shares a fence with it) so there is a continual cross-pollination/inbreeding between the two.

This is not an important issue, of course, but I'd still like to see some evidence that HEP people are making a significant contribution to laser fusion. Both fusion and HEP share a funding agency in the U.S., but I never encountered any real crosstalk between them when I was in HEP -- even though I worked with scientists from Livermore, and sometimes went there for meetings. (Of course, Livermore physicists are generally not a chatty bunch about other research that's going on there.)

Looking at a few papers on the Livermore laser project, I see that all of the authors seem to have backgrounds in plasma physics or lasers or the like, based on their previous publications.

 

[bigbadwilf]

This is not an important issue, of course, but I'd still like to see some evidence that HEP people are making a significant contribution to laser fusion. Both fusion and HEP share a funding agency in the U.S., but I never encountered any real crosstalk between them when I was in HEP -- even though I worked with scientists from Livermore, and sometimes went there for meetings. (Of course, Livermore physicists are generally not a chatty bunch about other research that's going on there.)

Looking at a few papers on the Livermore laser project, I see that all of the authors seem to have backgrounds in plasma physics or lasers or the like, based on their previous publications.

It does have some localized importance though, at least for me, as my parents met in the jointly-run accommodation (she was a computer programmer on the neutron source, before she retired, back in the days before magnetic media).
Agreed the laser fusion link is somewhat tenuous on a larger scale, however the plasma physicists, the laser physicists and the particle physicists all seem to speak a language if not the same, then definitely similar. Which is more can be said for the rest of us trying to follow what they're saying when they get into work-speech.

As you have a background in HEP, I was wondering if you could explain something to me: in Beta decay you have a neutron breaking down to form a proton and an electron, I understand that both protons and neutrons are made up of 3 quarks (up, up, down and up, down, down respectively), so in essence one up is becoming a down in the neutron in question. What I struggle with is that the process suggests to me an additional level of sub-quark complexity, and that's about where my poor non-physicist brain starts to overheat dangerously.



Is there any chance of a simple explanation?

 

[Chalnoth]

As you have a background in HEP, I was wondering if you could explain something to me: in Beta decay you have a neutron breaking down to form a proton and an electron, I understand that both protons and neutrons are made up of 3 quarks (up, up, down and up, down, down respectively), so in essence one up is becoming a down in the neutron in question. What I struggle with is that the process suggests to me an additional level of sub-quark complexity, and that's about where my poor non-physicist brain starts to overheat dangerously.



Is there any chance of a simple explanation?

Yup.

u -> d + e + v

That is, the up quark transitions to a down quark plus an electron and an electron neutrino. The intermediary is a W boson (this is a weak force interaction).

Did that help any?

 

[bigbadwilf]

Yup.

u -> d + e + v

That is, the up quark transitions to a down quark plus an electron and an electron neutrino. The intermediary is a W boson (this is a weak force interaction).

Did that help any?

Well, it's certainly easier to read than my version, but it's more the how does one quark change into another while spitting off a lepton and a boson that gets me a bit confused.

 

[Chalnoth]

Well, it's certainly easier to read than my version, but it's more the how does one quark change into another while spitting off a lepton and a boson that gets me a bit confused.

Well, it has to do with the way the W boson interacts with these particles. First, it may help to use this as a visual aid:
http://en.wikipedia.org/wiki/File:Standard_Model_of_Elementary_Particles.svg

Those are the particles of the standard model. The particles are deliberately arranged in a particular form: you see each quark paired with a partner. Up is paired with down, charm with strange, and bottom with top. In a similar manner, each lepton (electron, muon, tau) is paired with its own type of neutrino. The key point is that there exists what is known as a "vertex element" wherein you can interact a W boson with one particle in the standard model with its partner. That is, you can, with a W boson, interact an up quark with a down quark.

This means, for instance, if you start with an up quark, it can become a down quark if it emits a positively-charged W boson, or if it absorbs a negatively-charged one. If, on the other hand, you start with an electron neutrino, it can become a normal electron if it absorbs a negatively-charged W boson, or emits a positively-charged one.

So what happens with beta decay is that the down quark emits a negatively-charged W boson, becoming an up quark. Then the negatively-charged W boson rapidly decays into an electron and an anti-neutrino.

Of course, I should mention that this is a schematic view and it's a bit more complicated. But I think it's correct in essence.

 

[sfs]

It does have some localized importance though, at least for me, as my parents met in the jointly-run accommodation (she was a computer programmer on the neutron source, before she retired, back in the days before magnetic media).

Viewed in this light, I would certainly agree that fruitful cross-fertilization can occur between all sorts of fields. My own children are the result of a collaboration between a (now-ex) physicist and an economist, for example.