How to talk about Sickness?

 

 

                                                   Stop Saying - I Don’t Know

What Is Time?

 WHAT IS TIME?

Time is familiar to everyone, yet it's hard to define and understand. Science, religion, philosophy, and the arts have different definitions of time, but the system of measuring it is relatively consistent.Clocks are based on seconds, minutes, and hours. While the basis for these units has changed throughout history, they trace their roots back to ancient Sumeria. The modern international unit of time, the second, is defined by the electronic transition of the cesium atom. But what, exactly, is time? Physicists define time as the progression of events from the past to the present into the future. Basically, if a system is unchanging, it is timeless. Time can be considered to be the fourth dimension of reality, used to describe events in three-dimensional space. It is not something we can see, touch, or taste, but we can measure its passage. 

Physics equations work equally well whether time is moving forward into the future (positive time) or backward into the past (negative time.) However, time in the natural world has one direction, called the arrow of time. The question of why time is irreversible is one of the biggest unresolved questions in science.

One explanation is that the natural world follows the laws of thermodynamics. The second law of thermodynamics states that within a closed system, the entropy of the system remains constant or increases. If the universe is considered to be a closed system, its entropy (degree of disorder) can never decrease. In other words, the universe cannot return to exactly the same state in which it was at an earlier point. Time cannot move backward.As far as the universe is concerned, time had a beginning. The starting point was 13.799 billion years ago when the Big Bang occurred. We can measure cosmic background radiation as microwaves from the Big Bang, but there isn't any radiation with earlier origins. One argument for the origin of time is that if it extended backward infinitely, the night sky would be filled with light from older stars.

Will time end? The answer to this question is unknown. If the universe expands forever, time would continue. If a new Big Bang occurs, our time line would end and a new one would begin. In particle physics experiments, random particles arise from a vacuum, so it doesn't seem likely the universe would become static or timeless. Only time will tell.

Где найти друга по переписке

 

Где найти друга по переписке: 4 лучших сайта

1. interpals.net — на сайте можно бесплатно зарегистрироваться и найти друга по переписке, предварительно просмотрев его профиль и решив, найдете ли вы интересные темы для общения. Ресурс довольно активный, постоянно находятся онлайн как минимум 3000-4000 человек.
2. mylanguageexchange.com — бесплатный сайт для поиска друзей за границей. На сегодняшний день общее количество членов сайта — более 550 000.
3. studentsoftheworld.info — тоже полностью бесплатный сервис для поиска друга по переписке. Ориентирован как раз на студентов, изучающих английский язык.
4. penpalworld.com — на сайте зарегистрировано более 2 000 000 пользователей. Бесплатно можно писать только 3 пользователям в день (в принципе, этого может быть вполне достаточно для общения). Чтобы писать бо́льшему числу участников, нужен платный аккаунт.