Gravitational radiation from colliding vacuum bubbles

Journal Article · Mon Jun 15 00:00:00 EDT 1992 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.45.4514· OSTI ID:7184557

Kosowsky, A; Turner, M S; Watkins, R ^[1]

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1. NASA/Fermilab Astrophysics Center, Fermi National Accelerator Laboratory, Batavia, Illinois 60510-0500 (United States) Departments of Physics and Astronomy Astrophysics, Enrico Fermi Institute, The University of Chicago, Chicago, Illinois 60637-1433 (United States)

In the linearized-gravity approximation we numerically compute the amount of gravitational radiation produced by the collision of two true-vacuum bubbles in Minkowski space. The bubbles are separated by distance {ital d} and we calculate the amount of gravitational radiation that is produced in a time {tau}{similar to}{ital d} (in a cosmological phase transition {tau} corresponds to the duration of the transition, which is expected to be of the order of the mean bubble separation {ital d}). Our approximations are generally valid for {tau}{approx lt}{ital H}{sup {minus}1}. We find that the amount of gravitational radiation produced depends only upon the grossest features of the collision: the time {tau} and the energy density associated with the false-vacuum state, {rho}{sub vac}. In particular, the spectrum {ital dE}{sub GW}/{ital d}{omega}{proportional to}{rho}{sub vac}{sup 2}{tau}{sup 6} and peaks at a characteristic frequency {omega}{sub max}{congruent}3.8/{tau}, and the fraction of the vacuum energy released into gravitational waves is about 1.3{times}10{sup {minus}3}({tau}/{ital H}{sup {minus}1}){sup 2}, where {ital H}{sup 2}=8{pi}{ital G}{rho}{sub vac}/3 ({tau}/{ital H}{sup {minus}1} is expected to be of the order of a few percent). We address in some detail the important symmetry issues in the problem, and how the familiar quadrupole approximation'' breaks down in a most unusual way: it {ital overestimates} the amount of gravitational radiation produced in this highly relativistic situation by more than a factor of 50. Most of our results are for collisions of bubbles of equal size, though we briefly consider the collision of vacuum bubbles of unequal size. Our work implies that the vacuum-bubble collisions associated with strongly first-order phase transition are a very potent cosmological source of gravitational radiation.

• OSTI ID: 7184557
• Journal Information: Physical Review, D (Particles Fields); (United States), Vol. 45:12; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
GRAVITATIONAL RADIATION
CALCULATION METHODS
UNIVERSE
PHASE TRANSFORMATIONS
BUBBLES
COSMOLOGY
ENERGY DENSITY
HUBBLE EFFECT
MINKOWSKI SPACE
NUCLEATION
NUMERICAL ANALYSIS
PARTICLE INTERACTIONS
SCALAR FIELDS
SYMMETRY
TIME DEPENDENCE
VACUUM STATES
INTERACTIONS
MATHEMATICAL SPACE
MATHEMATICS
RADIATIONS
SPACE
662110* - General Theory of Particles & Fields- Theory of Fields & Strings- (1992-)