Thursday 13 August 2015

Time

In modern physics time is such things that we never call it as time. We have to consider space with time. In new era of physics time and space are in one continuum. Hence, it would be very scientific, not let alone "time" rather, "space time". Simply, we can say space time instead of time alone. From the emergence of Einstein's general theory of relativity time became interrelated with space. Time is relative just like mass and speed.
Scientists have been tried enough to discovery of inner theme of time flow from the past to future through present. If we look at our clock, it may be seems to simple of the time flow. Someone may ignore to think about of time flowing, least they lose their  valuable time. Someone may not agree it as a very complex topics of science. It is a perceptual matter concerned with psychology. When people see something visually happening, human take it as a simple matter. But it is real that behaviour of a small clock is concerned with the behaviour of big universe. It may be relates with different phenomena in universe.
I think human brain can easily assess past than future. Before million years ago what was happened we did not see with our eye and after million years latter what will be happen may not see. But making relationship of our visual facts we can imagine and assess something that what may be happen or what was happened. Both of these the assessment of past is more easy than the assessment of future. Because present everything in universe have established through a generalised process and every consequence of happening may transformed into present matter from the ancestors. Whatever, to investigate the origin of time, if we drive our memory to past as possible as far we can drive. We may reach at the conception of singular point from where big bang was started and the universe was started its expansion that is till now expanding. If someone make a relationship of time with planets motion, it would not be very wrong thinking to make a relationship with universe expansion. If there have doubt with complex restriction by complex acceptable theory of physics, it may draw a conclusion about the origin of time flow started from the initial moment of big bang. But this may be authentic and undoubtedly, only when scientists will accept of existence of only one universe. But conception of multiple universe again will make a complexity to draw a conclusion about the origin of time Before 4000 years ago human civilisation learns to measuring time. To measuring time, sunlight and shadow was taken as a standard of time flow. Sundial is such kinds of time measuring instrument, that was first used to measure time flow on the basis of shadow movement by the effect of sunlight. Another form of clock was used by measuring the level of water and sand. In seventeenth century pendulum clock was invented.  After invention of chronometer by John Horrison measurement of time became more accurate. After a period of spending time, human abled to invent quartz clock and atomic clock. Measurement of time by quartz clock is based on the property of quartz crystal of exhibiting piezoelectric effect. Atomic clock is a certain type of clock based on natural process that certain type of atom causes a natural change within it within a certain period of time. Just for example, cesium is such kinds of radioactive element that emits specific frequency of radiation. The oscillation per unit time is defined as frequency.  Before invention of atomic clock time was based on the earth rotation surrounding the sun. One rotation about earth's own axis was a day. After inventing the modern measurement techniques of time, ephemeris second became the standard of time measurement. Second is defined as 1 divided by 315569259747 of tropical year AD. Tropical year is the time taken by sun required for passing between successive spring equinoxes. Just like mass, time also relative in nature. Time is dependent on space. Einstein's general theory of relativity provides us a conception of time and space to integrate into a unique continuum, that is called space time. The conception of Sir Issac Newton that time is not absolute, but fact relative. This conception leads Einstein to develop theory of relativity. But during past 100 years before it was thought that time flows in same rate for every observers in universe. This conception about time flow is now out dated.
By observing the stability of moving cesium clock and stationary cesium clock we can find the evidence of relativity of time. Moving clock more stable than stationary clock. It is due to less decaying of particles. Moving radioactive elements are found less particle to radiate than stationary radioactive element. Hence, moving radioactive element have more life time. It is the Lorentz's effect on moving clock that proves the relativity of time.

Attractive force

The force acting among the objects that tends to closer together is attractive force. The opposite concept of attractive force is repulsive ...