The animation below illustrates how gravitational waves are emitted by two neutron stars as they first orbit each other and then coalesce. Though gravitational waves were predicted to exist in 1916, actual proof of their existence wouldn't arrive until 1974, 20 years after Einstein's death.
Uroabdomen can result from various causes, but the most common is related to trauma. Damage to the kidney, ureter, bladder, or urethra may cause urine to leak into the abdomen. Some common forms of trauma that can result in a disruption of the urinary tract in cats include:
UTI left untreated for weeks after the incidence of primary symptoms, causes the bacteria colonizing the bladder to move upwards, infecting the ureters. This leads to accumulation of urine in the ureters as well. When ureters are not completely emptied of urine, there is swelling and intense pain.