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User avatar #2187 - indone (06/29/2014) [-]
Harnessing the force of gravity like we have harnessed the strong/weak nuclear force
Say, lets discuss a few ideas behind gravity.
Gravity is
1. One of four known fundamental forces in the universe. Gravity was one of the forces that split away from the prime force that held them all together like a crystal.
2. Gravity is surprisingly enough the weakest force in this universe to my knowledge, which some physicist explain with the multiverse
3. The mechanisms behind gravity are not very well understood, I've heard
a) That it is simply the attraction of mass to other mass without any actual me... That doesn't make sense. Scrap this proposition
b) an elementary particle called "gravaton" "gravitron" and so on.
4. Dark energy, I believe if I'm not wrong, excerpts antigravity somehow. This is noticeable because galaxy clusters are being forced away from eachother at an alarming rate
User avatar #2246 to #2187 - givememoarpony (07/02/2014) [-]
There has been no grand unified theory that conclusively combined and derived all 4 interactions that can even be tested, and certainly not one that hypothesizes that the forces were held together like a crystal. The general idea is, as with the Higgs mechanism that gave rise to the weak and electromagnetic forces, as well as the Higgs boson, from the single electroweak interaction (which is not a thing, but a system of equations mapping the entire possibilities of interactions), that there exists a single force in energy levels high enough, and the force breaks apart into differently acting components when the energy levels become minimal compared to a ground level energy state. The most correct analogy would be a change in dimension once the spontaneous symmetry breaking occurs and the ball falls from the top of the Mexican hat, not some crystal. This analogy makes the most sense physically because the three forces of the Standard Model are defined in terms of a mathematical group, a concept in abstract algebra. For example, rotation in 2D space (more specifically, conservation of a value or equation in 2D rotation) is defined by the group SO(2), consisting of orthogonal matrices with determinant 1. Likewise, the electromagnetic force is defined on the group U(1), the weak force on SU(2), the electroweak force on U(2) and the strong force on SU(3). The Higgs mechanism breaks U(2) into SU(2) x U(1). But a similar thing cannot be done with general relativity because gravity is too nonlinear to be fit into the specific type of equations that reveal these groups (they are derived from the Yang-Mills Lagrangian).
User avatar #2250 to #2246 - indone (07/02/2014) [-]
Crystal was just a metaphor for them being unified once
User avatar #2248 to #2247 - givememoarpony (07/02/2014) [-]
Gravity is perfectly explained by the Einstein field equations of general relativity, which attribute the gravitational field to acceleration in space-time caused by space-time curvature, which is connected via the equations to the stress-energy tensor, which is a representation of the total energy, momentum and stress of an object. Problems arise when these equations are treated as quantum fields, where the energy levels cannot be rounded to any finite number (by a tweak called renormalization, which is a whole 'nother problem on its own) like they can in other forces, but end up resulting in infinities. This is because the equations for gravity cannot be reduced to the Yang-Mills equations. I speculate that this fundamental disparity in how these forces act is due to the three standard model forces being defined as projections of discrete space coordinates onto Minkowski space-time coordinates, while general relativity is defined on the Minkowski coordinates themselves. This is typically solved by bringing in tetrads, which represent a projection of the ideal flat space-time coordinates (or Lorentz coordinates) onto the curved Minkowski coordinates, but that complicates equations even more. That is why theorists generally do not use tetrads in their failed attempts at quantizing the gravitational force, and instead use low-energy linear approximations, by using a Higgs-like mechanism of separating the curved metric into the constant flat metric plus an anomaly, like the Higgs field being separated into the ground level energy state plus an anomaly and expanding the equations. Still, these failures strongly suggest that gravity is of a fundamentally different nature than the other forces. Gravity is the weakest for the same reason: its ground energy state is the Planck energy, while the energies of the other forces are vastly lower, because no such energy can be greater than the Planck energy.

User avatar #2249 to #2248 - givememoarpony (07/02/2014) [-]
Because of this, those energies are far more easily passable, so those forces become much stronger and yet with much less range. That's the best explanation I can think of right now.

Gravity does have a mechanism in its present conception and it is the curved space-time of general relativity. These equations detail how the metric (which represents the curvature of space-time) is affected by the presence of energy and how the energy would move on the space-time in line with the tendency to move toward the state with the least energy. Dark energy comes from a certain application of those equations in a certain metric (called the FLRW metric) that makes certain plausible assumptions about the universe (like homogeneity and isotropy) to approximately describe the evolution of the universe as a whole. When Aleksandr Friedmann first did this, he showed that general relativity implied that the universe was expanding. Einstein found that nonsense and corrected his equations with a little tweak called the cosmological constant which modified the Friedmann equations enough to exert a negative pressure that keeps the universe constant. But when Hubble then showed that the universe was, indeed, expanding (i.e. the spatial coordinates were expanding and moving apart from each other, not that Hubble actually saw the borders of space getting expanded), Einstein erased the cosmological constant and deemed it the biggest blunder of his life. But when it was revealed that the expansion of the universe was accelerating, the cosmological constant was revived and its value is actually known (~10^-120 Planck energies). People speculated on whether this constant is related to the cosmic inflation which is thought to explain the accelerated expansion (and has evidence behind it). Dark energy is a possible source of the cosmological constant that does not change density as the universe expands, thereby creating a negative pressure as shown by the equations.

You might want to look into it.
User avatar #2251 to #2249 - indone (07/02/2014) [-]
This is too much for me right now, but I'm gonna learn it some day. The ghost of dunning Kruger chased me there.
#2252 to #2251 - anonymous (07/03/2014) [-]
Really? really? really kid? face it, you didnt think you knew this stuff, you were just bullshitting and hoping someone would think you are smart if they didnt actually read your stupid dribble
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