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2
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4answers
2k views

Why doesn't fusion contradict the 1st law of thermodynamics?

I was reading up on the 1st law of thermodynamics for my Chemistry exam and I was wondering why doesn't fusion contradict the 1st law of thermodynamics? The 1st law states that The energy of an ...
2
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0answers
81 views

Calculating the minimum Lawson parameter for sustained d-d fusion

Calculate the minimum Lawson parameter for sustained deuterium-deuterium fusion in a plasma with an energy of 10 keV. I have been given the above question as part of a homework assignment and help ...
5
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4answers
3k views

Where does the energy produced by fusion come from?

Fission, in layman's (or "initiate's") terms, is easy enough to understand; a large atom with a lot of protons and neutrons requires a large amount of force provided by the strong interaction to ...
3
votes
2answers
195 views

Neutron generators as Fusion reactor

One way of generating neutrons is by fusing D-D or D with T. In neutron generators that work by acceleration D-ions into a solid matrix of e.g. metal and T or D (metal hydrides). Such generators can ...
2
votes
1answer
304 views

Is man-made Carbon Fusion possible?

In a type Ia Supernova, the carbon accumulated in the earlier stages of a stars death fissues to create even heavier elements. Could this be used by humans aswell? Is it theoretically possible to ...
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3answers
2k views

Nuclear fusion: what causes this “resonance” peak?

Can anyone explain why the $^{11}\mathrm{B}\mathrm{H}$ fusion cross-section has a peak near 150 keV, and why $\mathrm{D}\mathrm{D}$ and $\mathrm{D}\mathrm{T}$ have no such sharp peaks?
0
votes
0answers
117 views

Can we use a warp bubble for nuclear fusion?

I understand NASA is now experimenting with a tweaked Alcubierre drive. Apperantly some physicists predict crazy heat (hotter than the sun) inside the warp bubble caused by Hawking radiation (recent ...
1
vote
1answer
150 views

Is there a good summary of all nuclear fusion approaches?

I am pretty sure, that during last 60 years of well-funded research a lot of ideas on nuclear fusion were already tried and ruled out. Is there some summary describing all of them and why they ...
4
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2answers
774 views

Could we use particle colliders as fusion generators?

So I know the basic gist is that fusion power's main issue is sustaining the fusion. I also know that there are two methods. The Torus method and the laser method. The torus magnetically contains ...
4
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0answers
66 views

How fission and fusion create energy? [duplicate]

Possible Duplicate: How to explain $E=mc^2$ mass defect in fission/fusion In order for energy to be released, mass has to be "lost", because mass is a form of energy. In my science class, ...
7
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5answers
2k views

What are the challenges to achieving cold fusion?

I am an absolute neophyte regarding physics. What are the challenges to achieving cold fusion? I'm not sure this is a duplicate of Why is cold fusion considered bogus?, because that question is ...
1
vote
1answer
419 views

Complete list of nuclear fusion reactions

Could anyone suggest good source of all fusion reactions and their cross section vs energy graphs, including ones which were ruled out for nuclear fusion reactors (i.e. including endothermic and ...
3
votes
1answer
100 views

Could tidal effects make matter hot enough for nuclear fusion?

There was a recent question about cosmological firewalls. Putting aside questions of entanglement and information and looking at the problem from a pure mechanical viewpoint, we know that although ...
7
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3answers
508 views

Nuclear fusion : ion vs atom fusion cross section?

I've read critique on ITER project (in Russian), and one of points was that cross section of ion-ion fusion is much lower than ion-atom and atom-atom, and that's the reason why it likely to not work. ...
3
votes
1answer
400 views

“Dynamic Albedo of Neutrons” and all these Farnsworth fusors

I've checked specs of Russian "Dynamic Albedo of Neutrons" module on Mars MSL rover - it can do 10^8 neutron pulses at 10 pulses per second. It works on D-T reaction in tiny linear accelerator, and ...
3
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3answers
1k views

Can fusion and fission happen at the same time, in the same place?

Can fusion and fission happen at the same time, in the same place? I was talking with a friend, and he thinks that fission and fusion happen at the same time at the sun, is that true? I guess this ...
16
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2answers
520 views

Is there a sound theoretical argument against inner-shell induced nuclear chain reactions?

There is a claim often made about cold fusion, that it is excluded theoretically. The main theoretical argument is that electronic energies are too low to overcome the Coulomb barrier, since d-d ...
5
votes
1answer
3k views

How to explain $E=mc^2$ mass defect in fission/fusion

What is the nature of nuclear energy? This is closely related to the correct explanation of mass defect. I did some research of that topic and cannot come to a single comprehensive and consistent ...
4
votes
1answer
137 views

Helium Fusion and the Origin of Elements

In the fifth of his Messenger Lectures Feynman mentions the fact that Carbon-12 has an energy level at 7.82 MeV. He then states that this is what enables the fusion of three Helium-4 ions into Carbon ...
11
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2answers
375 views

How large can you make a tokamak?

I've seen questions on how small you can make a tokamak. But I haven't yet seen any "physical" upper limit on the tokamak design. If you take a wind turbine for example, doubling the linear ...
2
votes
1answer
136 views

How is/do they plan on having fusion energy collected at the National Ignition Facility?

I was just watching a program on television showing how the method they use at the National Ignition Facility to attempt to achieve fusion is to fire extremely powerful lasers at a small pellet of ...
1
vote
1answer
173 views

Why does a coulomb explosion induce fusion?

If you strip the valence electrons apart with a very short intense electromagnetic field the remaining core explodes in a so called coulomb explosion. But experiments have shown that under certain ...
4
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3answers
1k views

How much of the energy from 1 megaton H Bomb explosion could we capture to do useful work?

The world is full of nuclear warheads being stockpiled. Controlled fusion power seems a long way away. Could we put these warheads to better use by exploding them in a controlled way and capturing ...
2
votes
4answers
421 views

Should we forget fusion and focus on geothermal power? [closed]

Firstly I can say that I would love us to come up with a sustainable fusion solution. However with the latest estimates being 2050 at the earliest for an effective fusion solution and the planets ...
3
votes
2answers
278 views

Proposed Closing of Alcator C-Mod Fusion Tokamak

So I have friends at school who are petitioning against the proposed closing of the tokamak (refer to the recently released FY 2013 Administration Budget). I told said friends that before I signed the ...
3
votes
1answer
251 views

role of pure mathematics in fusion?

Is there any way a pure math guy can get his rigorous math fix while simultaneously moving fusion research forward? Is fusion simply too complicated to take a pure math approach? What open math ...
2
votes
1answer
294 views

How to initiate fusion explosion without a fission trigger

I'd like to know what theoretical methods for initiating a fusion detonation without a fission trigger exist, and which would be the most practical in the near future. I'd also like to know how small ...
7
votes
3answers
1k views

Why doesn't helium start to fuse while there is still hydrogen fuel?

In all the descriptions of the stellar life cycle it seems as though helium doesn't start being fused until all (most?) of the hydrogen is gone. Is this true? Why is this? It seems counter ...
3
votes
2answers
168 views

Proof Human Designs for Fusion Could Work

Are there convincing proofs on paper that fusion is possible the various ways humans are trying to design machines to do it or is the only way absolutely proven to work in theory also the only way ...
1
vote
3answers
2k views

The amount of energy required to break the Coulomb Barrier

This web page says that only 3-10 keV of energy is required to break the Coulomb barrier for colliding hydrogen nuclei. Pretty far from what originally said. Is this true? Does this have something ...
3
votes
2answers
989 views

Is the E-cat for real?

Does this thing really do what they say? http://www.youtube.com/watch?v=EhvD4KuAEmo If it does, it looks like this will probably be the biggest breaktrough in science ever :)
3
votes
2answers
187 views

Does magnetic geometry determine the scaling of a Polywell fusor?

Does magnetic geometry determine the scaling of a Polywell fusor? Forgive imprecise terminology here - by "magnetic geometry" I mean the configuration of the magnets, the configuration that creates ...
2
votes
1answer
287 views

How does the internuclear repulsion vary in Hydrogenic atom collision?

Hydrogen fusion requires two hydrogen nuclei to get close enough (typically a few fm) to fuse. Much of the problem of creating a fusion reactor is overcoming the Coulomb repulsion between a pair of ...
6
votes
1answer
167 views

Recent news about Tokamak

I first heard about the Tokamak in highschool 10 years ago and was wondering how far the technology has come since then. Can it sustain a reaction for more than a few seconds? Are these devices ...
7
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2answers
385 views

What elements can be created in the fusion process of different types of stars?

As I understand it fusion inside a sun can produce heavier and heavier elements until some sort of "nucleus size limit" is reached. As far as I understand, the limit is thought to be reached with the ...
12
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2answers
350 views

Hydrogen as a fuel in Sun

The source of Sun's incessant energy is hydrogen; which is continuously converting to helium through nuclear fusion reaction releasing energy. Why does not all hydrogen convert into helium in one big ...
1
vote
3answers
799 views

Lightning and nuclear fusion

I'm going to be brief, I just saw a Discovery Channel show that showed a lot of interesting phenomena around lightning (like elves, how cool is that(!)), and got me wondering. 1) Thinking of ...
2
votes
3answers
703 views

cosmic radiation muons as a source for muon-catalyzed fusion

taking rough numbers from here and here, it seems that with natural cosmic radiation sources, we could sustain $10^6$ muon-catalyzed fusion reactions per square-meter per minute. This would be $14 ...
12
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3answers
1k views

How often does nuclear fusion occur within the human body?

I'm just curious. I figure atoms fuse occasionally just by chance, like quantum tunneling or rogue waves. Is this true? If so, any idea how often?
2
votes
1answer
436 views

Do Hydrinos Exist? [duplicate]

Possible Duplicate: Have the Rowan University “hydrino” findings been replicated elsewhere? I came across this controversial company: Black Light Power I want to know if there ...
4
votes
6answers
748 views

Is there any inherent danger in operating a Thermonuclear Reactor?

Nuclear fusion research appears to promise sustainable, practically unlimited energy, and according to ITER it will be a perfectly safe, non-polluting source of energy. My question is if there are ...
1
vote
2answers
120 views

Light bending surfaces and energy funneling properties

In the last year there has been fuzz regarding metamaterials studied for the purpose of cloaking, and it seem to me they are somewhat glorified 2D waveguides, but in any case it seems a reasonable ...
5
votes
2answers
2k views

Origin of elements heavier than Iron (Fe)

In all the discussions about how the heavy elements in the universe are forged in the guts of stars and especially during a stars death, I usually hear that once the star begins fusing lighter atoms ...
2
votes
1answer
449 views

How much energy can be extracted from hydrogen?

http://en.wikipedia.org/wiki/B-L says that the difference between baryon number and lepton number is conserved. Ordinary hydrogen has one of each, but turning it into helium releases only the binding ...
24
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9answers
8k views

Can Jupiter be ignited?

Our solar system itself contains two candidate "Earths" One is Jupiter's moon Europa and another is Saturn's moon Titan. Both of them have the problem of having at low temperature as Sun's heat ...
5
votes
4answers
626 views

Help fill in my understanding of the Polywell fusion reactor

Polywell is a proposed new type of fusion reactor, which is designed to use magnetic fields to overcome the problems with the Elmore-Tuck-Watson fusor. I'm trying to understand exactly how it works. ...
8
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5answers
968 views

What new breakthrough energy technologies are close to being realized? [closed]

Energy production is one of the burning issues for humankind. There has been some talk about future energy technologies including Fusion, Anti-matter annihilation and Zero-point-energy (from most to ...