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-4
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0answers
41 views

could bacteria perform nuclear fusion of hydrogen atoms [closed]

Consider a bacteria that produces a protein that reacts in such a way as to force two hydrogen atoms to fuse. Is such a protein possible? Could the energy produced be harnessed. Is this sort of thing ...
6
votes
4answers
619 views

Tokamaks and the reason they are still not efficient

I'm curious about why tokamaks are inefficient as generators. In laymans terms, what is the main reason(s) tokamaks still cannot be used as generators? My limited understanding of tokamaks tells me ...
2
votes
1answer
7k views

What is the lowest possible theoretical temperature that nuclear fusion can occur at?

I am not talking about the pseudo-science of so called cold fusion I am interested in what temperature you can get away with to produce fusion reaction. I was thinking in terms of micro-fusion or at ...
1
vote
2answers
46 views

What is the role of plasma in nuclear fusion energy production?

I read that confined plasma in electromagnetic field uses in TOKAMARK nuclear fusion reaction.But I don't know what is the main role of plasma in fusion reaction. Is it use for producing energy ...
1
vote
1answer
107 views

Physics needed for a quite well understanding of nuclear bomb [closed]

I am an undergraduate student in physics and mathematics and one of my early dreams in physics was to understand the way nuclear weapons work. Is there a book which deals with the physics and the ...
1
vote
2answers
75 views

How much energy is released per unit mass from depressurizing degenerate matter?

A neutron star remnant consists mostly of neutron degenerate matter. If you happened to suddenly have 1 kg of it in your lap without the pressure necessary to keep it degenerate, I suppose it would ...
2
votes
1answer
147 views

Difference between fusion plasma and fluorescent lamp plasmas

How is the plasma in a compact fluorescent lamp (CFL) different from a plasma in say ITER or the sun? Why does ITER need 100MK and a CFL can work at practically room temperature (apart from the ...
0
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0answers
34 views

How much of fusion energy is positron-electron annihilation?

Stellar fusion involves protons becoming neutrons, which means ejecting a positron. Positrons annihilate electrons. This must deliver some energy in stellar fusion. But how much of the energy from ...
2
votes
1answer
1k views

What would happen if a hydrogen bomb were to explode in Saturn's atmosphere?

Purely hypothetical since any kind of testing in atmosphere/space is banned by international legislation/agreement. The humans have already bombed Luna so ... what could be expected to happen on ...
15
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1answer
633 views

Do supernovae produce an appreciable amount of lithium?

David Z's answer to this question got me wondering - is any appreciable amount of lithium produced as the result of a supernova explosion, either by fusion (which seems unlikely to me, but I don't ...
0
votes
5answers
97 views

Could we use nuclear bombs to generate electricity? [closed]

it seems the biggest problem with fusion power is confinement. on the other hand, we developed a fusion bomb in just a few years. i was wondering if it could be economically viable to use nuclear ...
1
vote
1answer
39 views

Does nuclear fusion of light nuclei occur in fire or boiling water?

At the temperature range of ordinary fire or maybe even ordinary boiling water, is the Coulomb potential between light atomic nuclei occasionally overcome to give way to fusion? Basically, how are ...
0
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0answers
27 views

ITER (International Thermonuclear Experimental reactor): material used

What structural material is being used in the ITER (International Thermonuclear Experimental reactor) to hold the plasma?
0
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0answers
46 views

Nuclear Fission and Fusion [duplicate]

I've read several other answers on here, but I still don't understand. Why do both fission and fusion release energy? I know the masses drop, but then why do the masses drop on both? Fusion is taking ...
18
votes
3answers
14k views

Why is the nucleus of an Iron atom so stable?

Lighter nuclei liberate energy when undergoing fusion, heavier nuclei when undergoing fission. What is it about the nucleus of an Iron atom that makes it so stable? Alternatively: Iron has the ...
8
votes
3answers
810 views

Why only light nuclei are able to undergo nuclear fusion not heavy nuclei?

Is it because of the binding energy or the binding energy per nuclei . I am having trouble with this whole binding energy and nuclear fusion concept.
5
votes
1answer
1k views

Reason why stars do not produce elements heavier than iron

In his book "Origins", Neil deGrasse Tyson says that "if you seek to split iron nuclei apart, you must them with additional energy. On the other hand, if you combine iron atoms they will also absorb ...
2
votes
2answers
129 views

Why does the core of a low mass star contract after reaching electron degeneracy?

I am learning about the lives and deaths of stars with a solar mass of 0.4-2. What I understand is that once the star stops hydrogen fusion after using up all its hydrogen, the star leaves the main ...
2
votes
0answers
34 views

How much energy does proton - carbon 12 fusion produce?

Page 25 of this document from the California Institute of Technology says that proton-carbon 12 fusion releases 7.54 MeV, while Wikipedia says it releases 1.95 MeV. Which one is correct?
1
vote
3answers
148 views

If planet like Jupiter is massive enough to hold hydrogen with its gravity is it bound to become a star?

I have been reading about Jupiter as of late and reason I am asking is if Jupiter has strong enough gravity to pull hydrogen to itself then it should be only matter of time when it will acquire enough ...
0
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0answers
36 views

What would keep a hypothetical fusion reactor from “igniting the atmosphere”? [duplicate]

So in the early days of Nuclear fission, there was a concern about the resulting energy igniting the atmosphere in a ball of fire and world-wide death which is awesome terrifying awesomely terrifying. ...
3
votes
1answer
85 views

Why did they start Wendelstein 7-X With Helium?

Just saw the first Hydrogen plasma at the Wendelstein reactor. I haven't found anywhere that gives a good explanation as to why they first used a Helium plasma - can anyone shed any light?
1
vote
1answer
27 views

So how much fuel does a hypothetical fusion plant need?

Reading about potential fusion plants it's easy to get the impression that we have nearly infinite access to the fuels required. But looking aside form how much we have available, I am interested in ...
1
vote
0answers
48 views

Can a spheromak propagate in vacuum?

I recently learned about (and am now fascinated by) spheromaks. I am no expert on plasma physics, but as I understand they are analogous to propagating toroidal vortices (smoke rings), but with plasma ...
6
votes
1answer
210 views

Why is a stellarator-type nuclear fusion reactor so oddly-shaped?

My first impression: It's a mess. Why is it shaped like that? I can't find any info about its shape other than it's a special arrangement of magnetic coils. (link) Here's some more images of it on ...
1
vote
2answers
138 views

Is there a difference in the energy output of a nuclear fission reaction as opposed to fusion?

For example, if I split a Helium atom will I get the same amount of energy as when I fuse Hydrogen into Helium? If there is a difference, what will be the difference (in general not according to ...
1
vote
2answers
80 views

How much iron would result of fusing a human body?

While discussing nonsense plots, a friend and I ran into the question of what would happen to a human enclosed perfectly with an enormous amount of energy, Antimatter or fusion level energy. It was a ...
0
votes
0answers
50 views

How is the interaction radius of fusion reactants determined?

To calculate the Coulomb barrier between two fusion reactants, the interaction radius (also called the fusion radius), r, must be known. How do I find the interaction radii of different nuclei?
0
votes
0answers
65 views

Is it possible for oxygen in the ocean to undergo nuclear fusion?

Could the oxygen in the ocean undergo oxygen burning (uncontrolled self-sustained fusion) if struck by a very large meteor or exposed to a similarly devastating cosmic catastrophe? Is it possible for ...
2
votes
1answer
73 views

Is neutron-neutron fusion viable?

Do I get unusual baryon maybe like pentaquark or just a pair of conjoined twin that is very unstable?
7
votes
2answers
1k views

Can the High beta fusion reactor work?

Are the claims made about the http://en.wikipedia.org/wiki/High_beta_fusion_reactor realistic? Can such a small fusion reactor really work?
2
votes
2answers
124 views

Temperature of fusion in the Sun vs. fusion in controlled experiments on Earth

I recently learned that hydrogen fusion (i.e., hydrogen to helium) experiments on Earth have been successful at temperatures in excess of 100,000,000 degrees Celsius. However, I also learned that ...
5
votes
2answers
605 views

How much faster is the fusion we make on earth compared to the fusion that happens in the sun?

I have come across many websites that states that the proton-proton fusion which is the dominant type of fusion that powers the suns, is extremely slow and that is why the sun is still burning to that ...
1
vote
1answer
56 views

Fusing Hydrogen with lightning

I've been reading about fusion recently (Specifically Deuterium fusion) and a friend of mine asked me if it was possible to fuse two Deuterium atoms with a lightning strike? Now this question has a ...
1
vote
2answers
176 views

Why do people say nuclear fusion is 50 years away? [closed]

This '50 years' number is floating around media pretty consistently, even the ITER road map claims that the first commercial reactor will happen post-2050. But why is that? I understand that there is ...
0
votes
2answers
143 views

Fusion reactors why does size matter?

I've been following articles about fusion recently, and with the ITER project mostly. I have noticed that their view point is they need to build a large scale reactor in order to achieve their goals. ...
-1
votes
2answers
366 views

What is the theoretical wattage output of a Tokamak fusion reactor?

By that I mean the complete radiative wattage of any type of energetic radioactivity or electromagnetic wave or even particle if that's what they output. My purpose is to compare this to the suns ...
4
votes
3answers
5k views

In nuclear fusion reaction, what is the percentage of mass converted to energy?

I read somewhere that it is about one percent of the mass, but I find this too high. Also I have done some calculations, for example, the Tsar Bomba was 50 MT bomb and weighed about 27 tons. Although ...
1
vote
1answer
190 views

Could atmospheric muons be used to catalyze nuclear fusion?

https://en.wikipedia.org/wiki/Muon-catalyzed_fusion I read above that some work as been done investigating whether muons could be used to catalyze fusion of deuterium and tritium. Apparently they can ...
2
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0answers
63 views

Usage of rare earth barium copper oxide (ReBCo) superconductors (for fusion reactors)

Recently, scientist from MIT have proposed a new design for a compact fusion reactor, see for example this ArXiV paper. I do not want to discuss the physics of their reactor but am more interested in ...
2
votes
0answers
40 views

Could anyone explain to me how the products of nuclear fusion/fission are predicted? [duplicate]

I have an idea of how quantum mechanics work, but I know too little to understand which products are a result of certain reactions like bombarding a certain atom with neutrons or just by natural ...
1
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0answers
29 views

Why can't electrostatically accelerated deuterium beams neutralized by electrons produce net energy fusion? [duplicate]

I was looking through the various nuclear fusion approaches and it struck me that they all suffered from one of two problems. Either they wasted a lot of energy trying to accelerate fusion fuel to the ...
5
votes
3answers
3k views

Why can't Iron fusion occur in stars?

It is said that iron fusion is endothermic and star can't sustain this kind of fusion (not until it goes supernova). However star is constantly releasing energy from fusion of elements like Hydrogen ...
12
votes
3answers
7k 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 ...
0
votes
2answers
176 views

How can the magnetic field of a tokamak or stellatron hold against the outwards plasma pressure?

I understand that magnetic containment structures like tokamaks generate a toroidal magnetic field in which the plasma particles move in helices around the field lines, because of the Lorentz force. A ...
2
votes
1answer
86 views

Help identifying a Fusion approach

Several years ago, I saw a Google video (back before the YouTube acquisition) where the leader of a group studying an unusual approach to fusion gave a presentation. His approach centered on a ...
0
votes
2answers
166 views

In a nuclear reaction, where does the energy go?

Lets say two hydrogen fuse together, where does the energy released go? Is it carried away as momentum imparted on the helium atom? Is it carried away in neutrinos? Is it carried away as gamma rays? ...
-1
votes
1answer
168 views

Mass loss for Fusion energy? [closed]

I am thinking how you can estimate the mass loss of the fusion energy for 1 kWh. I think you cannot use Einstein's $E=mc^2$ to calculate the mass loss in the fusion reaction of the Sun. How can ...
3
votes
1answer
850 views

Can we generate infinite energy by successive fission and fusion reactions?

Fission divides one Helium atom into two Hydrogen (Deuterium) atoms. And fusion, once again, puts together those two Hydrogen atoms into one Helium atom. In both reactions, overall output energy is ...
-1
votes
1answer
78 views

In what ways does the sun output energy?

I'm curious about the energy output of the sun, and how it breaks down. What fraction is from EM radiation, solar wind, neutrinos, et cetera? How does energy output vary over the EM spectrum? I was ...