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Can Event Horizons be Created at Lagrange Points in a Multiple Neutron Star System?

-- | November 5, 2015

Question: I have been interested in astronomy since I was a child. My question arose while I was studying the effects of Lagrangian points between multiple bodies.

Imagine a scenario of a binary (or multiple) neutron stars system. Provided the neutron stars are all very close to their critical mass and are running in a very compacted orbits around each other. Is it possible that the gravitational interaction between the neutron stars, similar to the principle of Lagrangian points, creates a spot of event horizon in the system?

I am deeply intrigued in this question, as I imagine the event horizon would be mobile and deforms corresponding to the motion of neutron stars. Also, with no singularity in the system, the event horizon would probably behave differently compare to those around a black hole. — Peterson

Answer: As you likely already know, Langrange Points are positions where the gravitational pull of two massive objects, such as the Earth and the Sun, precisely equals the centripetal force required for a small object to move with them. This is quite different than an event horizon, which is a boundary in space-time beyond which information cannot be transmitted. In other words, objects which are within an event horizon cannot be detected from an observer outside the event horizon. Event horizons are associated with very massive objects, such as black holes, which create gravitational fields that are so strong that they halt the travel of light propagating from the black hole. Neutron stars are not massive enough to produce event horizons. Also, Langrange Points do not naturally have the physical properties to create a massive object that can lead to an event horizon.

Jeff Mangum

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