# Tag Info

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The electromagnetic and weak forces have been unified into the theory of the electroweak force. The recent discovery of the Higgs boson put the icing on this particular cake. The strong force is described by the same type of quantum Yang-Mills theory as the electroweak force, however it is not unified with it. There have been several attempts at unifying ...

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Short answer: not yet. Long answer: The strong, EM, and weak forces have been unified via quantum field theories (QFT), while gravity is understood separately via general relativity. The two theories are currently incompatible with each other in the quantum regime. There are a variety of theoretical efforts underway to unify gravity with the other three ...

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is it possible to consider also the other fundamental forces [...] to be fictitious forces like gravity in the framework of general relativity? No, because the equivalence principle only holds for gravity. If we want a final unification of all fundamental forces, hasn't this feature of gravity to become a feature of the other forces as well? The ...

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The classical theory of electrodynamics can indeed be written as a geometrical theory in a similar way to general relativity. As it happens there is a question and answer addressing just this, but it's in the Maths SE: Electrodynamics in general spacetime. Classical electrodynamics is an example of a class of theories called classical Yang-Mills gauge ...

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On the quantum level, force is not acceleration. The concept of "fictitious force" makes no sense on a QFT level, because forces are interactions between quantum states, not the classical forces you might imagine. Quantum forces are not vector fields in space. The notion of "fictitious force" would mean that, e.g., the strong force is something influencing ...

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Once upon a time physicists dreamed that there would be one Theory of Everything (TOE) that would explain everything we see around us, or at least, from which all of the supposedly fundamental constants could be calculated and which would be so logically consistent it might explain why this is the only way things could be. That dream has died over the past ...

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...space, time, energy, matter or even motion. I'm not quite sure how these things relate to each other, such as whether or not one emerges from another, or if there are even more fundamental 'elements' that make up our universe. I'm also unsure if physicists agree everything can be reduced down to one of them, such as energy. What are all of ...

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Computational chemistry methods have advanced significantly in the last 5-10 years, including much more accurate DFT methods, quantum mechanical dynamical methods (like Car Parrinello MD, and better classical molecular dynamics techniques. That said, dealing with the dynamics of molecular reactions is an active area of research. Perhaps the most promising ...

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It depends on the level of theory you want to apply to a simulation. For example, the current state-of-the-art ab-initio calculations for a single low ernergy ($\lt 10~eV$) electron approaching and interacting with a molecule can cope with perhaps 20 to 40 electrons in the target molecule. Note that ab-initio calculations contain, in principle, no ...

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The time $10^{-23}$ seconds is about the time needed for light to cross a distance of $10^{-15}$ metres, so you could interpret it as a timescale in this sense. However I'm not sure that the time interval of such a strong interaction is a terribly useful concept. The nearest I can think of to a useful definition of time interval of such a strong interaction ...

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This time is a time of a nuclear reaction. There are nuclear reactions with their characteristic times - how fast nucleons are rearranged during reactions, something like that.

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I think the part about electromagnetic force being exponentially stronger than gravitation got through to you!(An easy way to picture this is how static electricity can lift up things against the pull of the earth!) About the feather,the way you are able to support the feather against the gravitational pull of the earth is because of the electromagnetic ...

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Quantum field theories have no direct notion of force, neither in the "physical approach" through a Lagrangian and the path integral, nor in the "mathematical approach" through Wightman, Haag-Kastler or other axioms. The theory of "force carriers" is developed without ever appealing to forces - one imposes a local gauge symmetry upon the theory and ...

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