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It has been asked frequently-- how come only the past is present in our memories and not the future? Why time travel is not an actuality and the process of aging is irreversible? Why is entropy a definitive constant? What came before the Big Bang? Was time existent before the Big Bang?  The answers to these complex questions can be potentially traced to the moment of the Big Bang. Sean Carroll, theoretical physicist of California Institute of Technology whose research focuses on theoretical physics, astrophysics and issues in cosmology, gravitation and field theory addresses this question below. Time definitively infuses our lives for it is constantly measured. It’s tracked, put to use, machines employ time and others are built to keep track of its passage and measure it just as a ruler measures distances. There is a stark difference between the ruler and the clock-- time doesn’t necessarily employ distances but it does take use of direction pointing past from future. Sean Carroll’...

What’s your opinion on String theory? Does this theory excite you? Mathematically, it seems perfect and quite amazing. Few aspects about it propose not one but several diverse dimensions, ones we’re not usually aware of, however we may be interacting with some of them all the time, entirely oblivious. If these dimensions are to be true, what would these dimensions look like and how might they affect us? And what is a dimension anyway? Two dimensions is just a point. We may remember the coordinate plane from math class with the x and y-axes. Then there’s the third dimension, depth (the z-axis). Another way to look at it is latitude, longitude, and altitude, which can locate any object on Earth. These are followed by the fourth dimension, space-time. Everything has to occur somewhere and at a certain time. After that, things get weird. Superstring theory, one of the leading theories today to explain the nature of our universe, contends that  there are 10 dimensions.  That’s nine...