Introduction to general relativity this energy loss would be too small to be detectable, but this energy loss was observed in 1974 in a binary pulsar called PSR1913+16. In such a system, one of the orbiting stars is a pulsar. This has two consequences: a pulsar is an extremely dense object known as a neutron star, for which gravitational wave emission is much stronger than for ordinary stars. Also, a pulsar emits a narrow beam of electromagnetic radiation from its magnetic poles. As the pulsar rotates, its beam sweeps over the Earth, where it is seen as a regular series of radio pulses, just
Beam bridge great distances; it only means that a series of beam bridges must be joined together, creating what is known as a continuous span. Beam bridge Beam bridges , also known as stringer bridges, are the simplest structural forms for bridge spans supported by an abutment or pier at each end. No moments are transferred throughout the support, hence their structural type is known as "simply supported". The simplest beam bridge could be a log (see log bridge), a wood plank, or a stone (see clapper bridge) laid across a stream. Bridges designed for modern infrastructure will usually be constructed of