On the total energy conservation of the Alcubierre spacetime
arXiv:2201.05684 · doi:10.1088/1475-7516/2022/07/030
Abstract
In this article, we consider the Alcubierre spacetime, such a spacetime describes a ``bubble'' that propagates with arbitrary global velocity. This setting allows movement at a speed greater than that of light. There are some known problems with this metric, e.g., the source's negative energy and the violation of the source's energy conservation when the bubble accelerates. We address these two issues within the realm of the Teleparallel Equivalent of General Relativity (TEGR). The energy conservation problem can be solved when considering the energy of the gravitational field itself. The total energy of the spacetime, gravitational plus source, is conserved even in accelerated motion. We explicitly show the dependence of energy and gravitational energy flux on the frame of reference, one adapted to a static observer and the other to a free-falling one in the same coordinate system. Addressing the problem of energy negativity of the source, we find that a static observer measures positive energy of the source, while an Eulerian observer measures a negative one. Thus, we surmise that negative energy may be a reference problem.
arXiv comment25 pages, 11 figures
References in corpus (28)
- Type Ia Supernova Discoveries at z>1 From the Hubble Space Telescope: Evidence for Past Deceleration and Constraints on Dark Energy Evolution
- The teleparallel equivalent of general relativity
- The warp drive: hyper-fast travel within general relativity
- An analysis of systematic effects in finite size scaling studies using the gradient flow
- Hyperfast Interstellar Travel in General Relativity
- Superluminal travel requires negative energies
- Superluminal travel requires negative energies
- A Superluminal Subway: The Krasnikov Tube
- The unphysical nature of "Warp Drive"
- Fundamental limitations on "warp drive" spacetimes
- Length measurement in accelerated systems
- On reference frames in spacetime and gravitational energy in freely falling frames
- The Energy Density in the Casimir Effect
- A `warp drive' with more reasonable total energy requirements
- Null geodesics in the Alcubierre warp drive spacetime: the view from the bridge
- Warp Drive With Zero Expansion
- Vacuum Electrodynamics of Accelerated Systems: Nonlocal Maxwell's Equations
- Weak energy condition violation and superluminal travel
- Generic warp drives violate the null energy condition
- Introducing Physical Warp Drives
- On Conserved Quantities for the Schwarzschild Black Hole in Teleparallel Gravity
- The energy-momentum of plane-fronted gravitational waves in the teleparallel equivalent of GR
- The Alcubierre Warp Drive: On the Matter of Matter
- Positive Energy Warp Drive from Hidden Geometric Structures
- Curvature Invariants for the Alcubierre and Natário Warp Drives
- Bianchi I metric solutions with nonminimally coupled Einstein-Maxwell gravity theory
- Conformal Gravity and the Alcubierre Warp Drive Metric
- Electrodynamics in accelerated frames revisited