The tag has no wiki summary.

learn more… | top users | synonyms

4
votes
2answers
65 views

Why does fusion stop at iron when nickel is most tightly bound?

My understanding is that stellar fusion naturally stops at iron because it is energetically unfavourable to grow the nucleus further. But iron is only the third most tightly-bound nucleus, nickel is ...
6
votes
1answer
130 views

What types of fusion reactions happened in population III stars?

I have read that, in smaller stars, such as our Sun, the fusion reaction that takes place is a proton-proton chain, or PP chain for short. From what I have learned, in larger stars, a different ...
1
vote
3answers
106 views

Does energy conservation not hold in fission and fusion processes?

I have read that during fission and fusion processes, there is some kind of equilibrium between the single nucleus and the disintegration products, so they are constantly being converted into each ...
12
votes
3answers
2k 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
0answers
35 views

Nuclear fusion ignited by neutron capture

Does anybody know if there was some attempt to make a hydrogen (fusion) bomb using neutrons released from the fission primary? e.g. using $^{10}\text{B}$ hydrate as a fuel? Assuming reaction ...
2
votes
1answer
42 views

How much potential fusion energy is in Earth's ocean?

Assuming the most efficient manner for extraction, and a ready supply of other necessary materials not mentioned herein, and given the current estimates about the volume of Earth's ocean, how much ...
0
votes
0answers
29 views

MHD stability - boundary conditions

In Freidberg's 'Plasma Physics and Fusion Energy,' ch. 12.4 p 311, right after deriving the Linear Force operator and momentum equation in which it is used $$ -\rho \omega^2 \boldsymbol\xi = ...
3
votes
3answers
536 views

Is nuclear fusion possible on planets in our Solar system?

Apart from thermo-nuclear reactions in the Sun, (and in hydrogen bombs and other methods developed by scientists) does nuclear fusion occur naturally in the planets? If not, why? Also, do the Sun ...
1
vote
1answer
37 views

What makes red giants big? [duplicate]

I read some about red giants and so far I understand red giants become exhausted of burning hydrogen in the core, so then start hydrogen burning at shell and may or may not be burning helium in the ...
2
votes
5answers
307 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
29 views

Could deuterium saturated palladium capsules be used for inertial confinement fusion?

NIF(National Ignition Facility at the Lawrence Livermore National Laboratory in California) uses the ICF (inertial confinement fusion) approach in order to harvest fusion energy. At NIF, indirect ...
4
votes
1answer
147 views

Chemical and stellar evolution in stars

I'm having an exam soon where I have to discuss/describe the follow figure: It's the first figure I have to explain, and it was on the same slide as the one below, so I'm thinking they are somewhat ...
7
votes
3answers
3k views

Can open, unsafe nuclear fusion reaction burn the atmosphere?

I happened to hear people saying that the nuclear fusion bomb tests could set the atmosphere on fire. I have some serious doubts about that - but I have no facts. Nuclear fusion reaction requires ...
2
votes
1answer
28 views

What is the main thermal energy source for a protostar, the contraction or the deuterium burning energy?

According to the virial theorem, when a protostar contracts, half of the gravitational potential energy is radiated and half is kept as kinetic energy of the falling material which in turn heats the ...
2
votes
1answer
50 views

Water behaviour under theoretical near-infinite pressure conditions

I've asked a similar question here but the answer given shows the behaviour of water under general conditions. I'd like to know what the behaviour of water is like as pressures increase towards ...
-1
votes
2answers
639 views

Quantum Mechanics and nuclear fusion

I've been told that, according to QM, when Hydrogen atoms are left together there is a non-zero probability that they spontaneously fuse (I accept this bit). I've been told further that, because of ...
1
vote
3answers
2k 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 ...
5
votes
4answers
5k 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 ...
2
votes
1answer
54 views

Questions regarding the feasibility of “Jupiter”-like fusion reactor

I was reading this post from this website: Turning Jupiter into a star It basically talks about whether fusion can or does happen in the core of Jupiter. I know Jupiter cannot become a star, but I ...
0
votes
1answer
76 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. ...
0
votes
1answer
28 views

Proton 'Laser' ? could we get a laser-like effect? [closed]

This is a speculative question. question: Can we gain protons, by smashing a high speed proton into a hydrogen plasma? Background: I was thinking about how lasers repeatedly send the photons thru ...
4
votes
0answers
165 views

Are Lockheed Martin nuclear fusion claims realistic? [duplicate]

Lockheed Martin reported breakthroughs on nuclear fusion technology for energy. Are these claims scientifically realistic? The claims have been reported in the media: ...
6
votes
1answer
676 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?
0
votes
0answers
35 views

Fusion plasma compression with liquid metal

General Fusion plans to use an imploding shockwave of molten lead to compress a magnetized plasma "spheromak" target in order to make it burn more efficiently. How come the lead does not quench the ...
2
votes
2answers
2k views

Would a matter-antimatter explosion cause fallout?

I know matter and antimatter annihilation release a lot of gamma rays which are considered ionizing radiation if I am not mistaken. But what if the explosion happened on the surface of the earth, ...
8
votes
3answers
3k 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 ...
3
votes
1answer
121 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 ...
4
votes
2answers
1k views

Is the E-cat by Andrea Rossi et al. 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 breakthrough in science ever :)
5
votes
3answers
295 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
54 views

Why is plasma confinement on the NIF called inertial confinement when it appears to be confined by pressure?

I've heard that unlike Tokamaks that use magnetic confinement of the plasma, the NIF project uses 'inertial' confinement. What's inertial about it? Do they spin the plasma to use angular momentum like ...
0
votes
1answer
44 views

Working of fusion reactor

The present type fusion reactors use the magnetic confinement technique for the production of energy. Moreover only 48% for the energy is only absorbed and converted into useful energy . Why we are ...
2
votes
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 ...
3
votes
2answers
111 views

Nuclear fusion using electromagnetic fields

I was just thinking about how deuterium and tritium are charged particles and so I couldn't help but wonder why we don't use the same process used in the LHC(electromagnetic fields to accelerate ...
3
votes
1answer
69 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
52 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
82 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
90 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. ...
33
votes
9answers
11k 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
votes
1answer
75 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
33 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
60 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
59 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
190 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 ...
0
votes
0answers
69 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
votes
3answers
201 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
votes
3answers
816 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
165 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
82 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 ...
6
votes
2answers
604 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
101 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 ...