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3
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1answer
35 views

What is relationship between Quantum tunnelling and Gravitational potential energy of stars?

Are there a direct mathematical relationship between Quantum tunnelling and Gravitational potential energy of stars? The true source of the Sun's energy was shown by Hans Bethe to be nuclear fusion ...
1
vote
1answer
34 views

How can fusion within the sun be possible if there is no such thing as helium-2 (2 protons, no neutrons)

As stated in the question where does the sun(or other star) get the necessary neutron in order to produce the Helium atom? and how does this process occur (explain how the neutron incorporates).
1
vote
1answer
33 views

How much fuel is needed for a constant-acceleration rocket?

My son and I have been discussing the concept of a constant-acceleration rocket, as described here and here. We're willing to assume advanced technology such as a fusion rocket, which, according to ...
2
votes
2answers
75 views

Can a laser be designed to ionize muonic atoms so as to prevent a-sticking?

Muon catalyzed fusion is currently little more than a lab curiosity today in part because of how many hydrogen nuclei can be fused before the muon is carried away by an alpha particle. ...
31
votes
9answers
9k 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 ...
2
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1answer
49 views

How long does it take plasma to radiate its heat?

Lets say we have 1 gram of plasma (Argon) at 1 million kelvin confined in a vacuum with electromagnets. If we keep the magnets on but shut down the device that heated the plasma, how long will it take ...
2
votes
1answer
25 views

Why is the triple product nτT used instead of the individual three criteria?

Why is the criteria for fusion represented as a triple product nτT instead of the n,τ,T individually? i.e saying the density has to be above this value, temperature above this value? What are the ...
2
votes
1answer
57 views

Why is the D+T fuel inside a pellet in two distintic regions in fusion after compression

Could anyone explain why the D+T inside the pellet is in two distinct regions? And why the center is a lot less dense than the outside region? I have been trying to find answers online but i cant ...
0
votes
1answer
41 views

The formation of shockwave inside pellets in inertial confinement fusion

In the explanations i have read on the internet about ICF they all explain that the top layer of the pellet or the ablator is heated till it explodes and this produces a reaction force which compress ...
1
vote
1answer
95 views

Help with Modeling a Liquid Vortex. (Related to General Fusion)

I want to model liquid lead swirling in a sphere. This is connected to General Fusion’s fusion machine. A 55 million dollar, Jeff Bezos funded, 60 person company trying to change the world with ...
2
votes
4answers
147 views

Why do almost all nuclear reactions release energy?

I'm just wondering why almost all nuclear reactions release energy, in a typical way, the mass defect is transformed into energy ? Is there a nuclear reaction that gains mass (resp. energy)? or most ...
0
votes
0answers
49 views

Understanding the concept of cross section

The cross section is a tiny area, measured in barns ($10^{-28} \mathrm{m^2}$), which relates to the probability of a reaction. But I have trouble interpreting that number. For example how can I ...
0
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3answers
102 views

Is the solar energy Infinite?

Is the solar energy coming from the sun infinite and will continue to be radiated to our earth forever? (discarding any outer factors) what's the sun's fuel?
2
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3answers
732 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 ...
4
votes
1answer
149 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 ...
-1
votes
1answer
72 views

Whether nuclear physics or nuclear engineering is suitable for doing research in nuclear fusion? [closed]

I want to do research in making nuclear fusion sustainable for electrical energy production , which field I should choose? and it is worth doing research in fusion now, since many of them are saying ...
5
votes
2answers
263 views

When did the first carbon atom in the Universe come into existence?

I am a chemist with a passion for astrophysics and particle physics, and one of the most marvellous things I have learned in my life is the process of stellar nucleosynthesis. It saddens me how my ...
0
votes
2answers
79 views

requirements for hydrogen fusion

What are the requirements for hydrogen atoms to go through fusion? Is it a ratio of heat to pressure or are there specific heat and pressure values that must be met (per atom or per mole?) Are there ...
2
votes
2answers
122 views

Can Deuterium undergo a nuclear fusion without the presence of Tritium?

I've been reading about fusion fuels for a while now, and I understand that in Lithium-Deuterium fuel, the neutrons from the fission reaction bombard the Lithium to produce Tritium and the D-T ...
3
votes
2answers
205 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 ...
8
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2answers
220 views

What is the difference between the KDEMO and DEMO projects?

I'm writing a paper on the future of fusion technology and I can't seem to find the difference between Europe's DEMO experiment and Korea's KDEMO except for the fact that they are both planned to ...
0
votes
0answers
51 views

Polarizing virtual photons to make fusion easier?

So, this is probably incredibly foolish, outlandish, etc but I figure I'd post it anyways. Basically I was thinking about how the Deuterium nuclei repel each other and how they do this by exchanging ...
0
votes
2answers
52 views

Energy realized in fusion and electrons?

I was doing this question about the energy released in a fusion reaction: In the mark scheme it included the mass of the electrons (for part cii) on the left and just used the mass of protons for ...
1
vote
1answer
65 views

Calculate the average temperature needed for hydrogen fusion reaction [duplicate]

my question is simple. How can we calculate the temperature needed in order to do the nuclear fusion things , and also the temperature after the reaction successful. If you can describe it, it ...
4
votes
1answer
79 views

Is nuclear fusion via underwater vacuum possible?

An under water explosion creates a bubbly which quickly collapses on itself. The action takes less that 1/100 of a second for bubbles less than a foot across. This creates a point of extremely ...
5
votes
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
200 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 ...
3
votes
2answers
133 views

How clean will first generation fusion reactors be compared to fission reactors?

Googling the topic seems to indicate that fusion reactors will produce less waste and less toxic radioactivity, but this fact never seems to be mentioned during the current debate over nuclear power. ...
16
votes
2answers
538 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 ...
1
vote
2answers
230 views

Light formed by the sun?

This is an extract from the astrophysics chapter in my book: Hydrogen atoms fuse to form helium. At the same time, lots of of gamma photons and neutrinos are produced. The photons take thousands ...
3
votes
1answer
57 views

pp chain gamma decay / intermediate state

Based on the first equation at http://en.wikipedia.org/wiki/Proton%E2%80%93proton_chain_reaction $$_1^{1}H+_1^{1}H \to _2^{2}He+\gamma$$ Is it correct to say that in the P-P chain two hydrogen atoms ...
4
votes
1answer
109 views

What does the Coulomb barrier really mean?

I realize I'm trying to get a simple answer on a complicated subject, but here goes anyway. I've done some research and I understand (well, mostly) about how Vc is the amount of energy required to get ...
0
votes
1answer
68 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
2answers
192 views

What is a simple mathematical model of a star?

I had a discussion at work regarding a recent fusion experiment in China that resulted in temperatures five times hotter than the Sun. Someone mentioned that no one can know the temperature of the ...
2
votes
1answer
308 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 ...
4
votes
1answer
176 views

Fusion: Why deuterium and tritium?

I would like to know why scientists try to use deuterium and tritium for fusion and not just the ordinary isotope of Hydrogen ${}^1H$?
0
votes
0answers
40 views

Does the plasma move in the tokamak?

I was reading about tokamaks, for usage in fusion, and it seems that the positive ions circle in one way in the toakmak, while the negative circles in another. That would make a lot of sense, as it ...
8
votes
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 ...
3
votes
2answers
721 views

What is the shielding in nuclear reactors mainly against?

I have a little knowledge about ionizing radiation and I have been confused over why nuclear reactors need these massive shields. So, if I am not mistaken, Alpha and Beta radiation are not that ...
6
votes
3answers
5k views

How do you build a nuclear reactor in your garage?

When I came across this link earlier today, I was astounded. Nuclear reactors are immensely complex devices that took scientists years to develop, and are usually housed in huge facilities. The link ...
4
votes
2answers
508 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 ...
7
votes
2answers
419 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 ...
0
votes
1answer
320 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
vote
2answers
1k views

How much iron would I have to shoot into the sun to blow it up?

My understanding--though it's from a Science Channel show so I'm not sure if it is correct--is that there is a fusion reaction happening in the center of the sun. Atomic nuclei are being created and ...
-1
votes
1answer
84 views

At what speed do things stop being stable and essentially become atomic bomb?

I know that when things go very fast (approaching the speed of light), they tend to turn into atomic bombs. What speed can you reach (in earth's atmosphere) before nuclear fusion begins. Does this ...
0
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0answers
71 views

Energy Density of Hydrogen Fusion

How much energy is derived from the full process from hydrogen-1 fused into helium-4? Including all the sub-reactions (H1 into Deuterium, etc).
3
votes
1answer
130 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
192 views

Are multi-megaton antimatter induced fusion explosions theoretically possible?

I just finished reading this research about antimatter induced fusion and thermonuclear reactions. And one conclusion I could make is that very little mass of antimatter (in range of micrograms) is ...
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?
10
votes
1answer
730 views

With what probability does nuclear fusion occur at energies far below the Coulomb barrier?

Even at the core of the sun, the temperature of $\sim 10^7$ K only results in $kT\sim1$ keV, which is about a thousand times less than the electrical potential energy of $\sim1$ MeV needed in order to ...