How big is the universe?
The dimensions of the universe depend on its age, shape, total mass and acceleration. The correct estimation of the size is around 156 billion light years. Much confidence can be put into this value as the instrument that has been used to measure is the latest WMAP telescope. This instrument can be used in deep-space calculations and has an error probability less than 1%. The error component has also been minimized through years of research and calculations.
Wilkinson Microwave Anisotropy Probe
The Wilkinson Microwave Anisotropy Probe (2003) established the Euclidian theory that the universe is flat throughout. The probe also revealed that our universe was expanding quickly, which also means that the heavenly masses are flying apart at ever increasing speeds. WMAP measured cosmic microwaves and background radiation accurately with an estimated 5% error component. The radius figures thus established are amazingly huge.
The radius figures that we have got at a certain point of time, are subject to change the very next moment. The Big-Bang theory suggests that a huge space can be created by a single explosion. Recent figures also say that the planets are getting farther away from each other, thus strengthening the same point. Explosions like the Big Bang are a continuous and random phenomenon in the outer space, so it can well be imagined how much more new space is generated with each of them.
Just as the concept of numbers, the very concept of space is infinite too. There is no limit by which one can define a space. There is always a space outside a certain limit. Thus reaching no limit at the end.
The distance upto which light can travel gives up an estimation of the universe. All our instruments can measure light year distance from this phenomenon, but we will never know what lies beyond that limit. For us, the universe ends there as we can’t measure further, but in reality it is only a part of infinity.
Study of old stars
Studying the old stars can give us an idea of the measurement of the universe. The oldest known stars are between 10 to 14 billion light years old. If we were able to find a star that is older than light could travel, all our assumptions would have stood wrong. It would have meant that there was more time for the star to evolve than the maximum time we have measured our universe to have existed. However, nothing as such has still been found, and we still hold to the calculations arrived at by the WMAP technology.
The theories of quantum physics, Feynman’s formula, probability amplitudes, wave function, contingency, and the concepts of indiscernible have led to the many worlds hypothesis. All this hypothesis aim to measure the exact spread and thickness of the universe, but as stated earlier they are with respect to a certain point in time.
Thus, it would be illogical outside realms when we are no knowledgeable enough of what lies inside.