Are there additional dimensions?
In trying to extend Einstein’s theory and to understand the quantum nature of gravity, particle physicists have posited the existence of spacetime dimensions beyond those that we know. Their existence could have implications for the birth and evolution of the universe, could affect the interactions of the fundamental particles, and could alter the force of gravity at short distances. The HENP’s research into string theories suggests extra dimensions, as discussed in question #9. Experiments at the Tevatron and other colliders will search for evidence of extra dimensions by looking for missing energy in the particles produced in a collision of two accelerated particles, such as the proton and an antiproton at the Tevatron accelerator. 11. How did the Universe begin? There is evidence that during its earliest moments the universe underwent a tremendous burst of additional expansion, known as inflation, so that the largest objects in the universe had their origins in subatomic quantum fuz
