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Bubble letter chain real11/4/2022 ![]() The second special case is decay into a space of vanishing cosmological constant, the case that applies if we are now living in the debris of a false vacuum which decayed at some early cosmic epoch. This possibility has now been eliminated. However, one could always draw stoic comfort from the possibility that perhaps in the course of time the new vacuum would sustain, if not life as we know it, at least some structures capable of knowing joy. Vacuum decay is the ultimate ecological catastrophe in the new vacuum there are new constants of nature after vacuum decay, not only is life as we know it impossible, so is chemistry as we know it. The possibility that we are living in a false vacuum has never been a cheering one to contemplate. The time required for the collapse of the interior universe is on the order of. #Bubble letter chain real free#Although this space-time is free of singularities, it is unstable under small perturbations, and inevitably suffers gravitational collapse of the same sort as the end state of a contracting Friedmann universe. The geometry of space-time within the bubble is that of anti-de Sitter space, a space much like conventional de Sitter space except that its group of symmetries is O(3, 2) rather than O(4, 1). Within the bubble, the effects of gravitation are more dramatic. In the presence of gravitation, though, the negative energy density of the true vacuum distorts geometry within the bubble with the result that, for a small enough energy density, there is no bubble with a big enough volume/surface ratio. ![]() In the absence of gravitation, this is no problem, no matter how small the energy-density difference all one has to do is make the bubble big enough, and the volume/surface ratio will do the job. For the vacuum to decay, it must be possible to build a bubble of total energy zero. In general, gravitation makes the probability of vacuum decay smaller in the extreme case of very small energy-density difference, it can even stabilize the false vacuum, preventing vacuum decay altogether. Ī paper by Coleman and de Luccia which attempted to include simple gravitational assumptions into these theories noted that if this was an accurate representation of nature, then the resulting universe "inside the bubble" in such a case would appear to be extremely unstable and would almost immediately collapse: #Bubble letter chain real full#Some false vacuum decay scenarios are compatible with survival of structures like galaxies and stars or even biological life while others involve the full destruction of baryonic matter or even immediate gravitational collapse of the universe, although in this more extreme case the likelihood of a "bubble" forming may be very low (i.e., false vacuum decay may be impossible). The effects could range from complete cessation of existing fundamental forces, elementary particles and structures comprising them, to subtle change in some cosmological parameters, mostly depending on the potential difference between true and false vacuum. If our universe is in a false vacuum state rather than a true vacuum state, then the decay from the less stable false vacuum to the more stable true vacuum (called false vacuum decay) could have dramatic consequences. This type of vacuum state is called a "false vacuum". ![]() It is possible that a physical vacuum state is a configuration of quantum fields representing a local minimum but not global minimum of energy. A true vacuum is stable because it is at a global minimum of energy, and is commonly assumed to coincide with the physical vacuum state we live in. Despite the name, the vacuum still has quantum fields. ![]() false vacuum Ī vacuum is defined as a space with as little energy in it as possible. The most common suggestion of how such a decay might happen in our universe is called bubble nucleation – if a small region of the universe by chance reached a more stable vacuum, this "bubble" (also called "bounce") would spread.Ī false vacuum exists at a local minimum of energy and is therefore not stable, in contrast to a true vacuum, which exists at a global minimum and is stable.ĭefinition of true vs. It may last for a very long time in that state, but could eventually decay to the more stable state, an event known as false vacuum decay. In quantum field theory, a false vacuum is a hypothetical vacuum that is stable, but not in the most stable state possible (it is metastable). Therefore, the transition to the true vacuum must be stimulated by the creation of high-energy particles or through quantum-mechanical tunneling. ![]() Note that the energy E is higher in the false vacuum than that in the true vacuum or ground state, but there is a barrier preventing the field from classically rolling down to the true vacuum. A scalar field φ (which represents physical position) in a false vacuum. ![]()
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