Studying chaos with one of the world's fastest cameras
There are things in life that can be predicted reasonably well. The tides rise and fall. The moon waxes and wanes. A billiard ball bounces around a table according to orderly geometry.
There are things in life that can be predicted reasonably well. The tides rise and fall. The moon waxes and wanes. A billiard ball bounces around a table according to orderly geometry.
General Physics
Jan 13, 2021
3
262
Apart from black holes, magnetars may be the most extreme stars in the universe. With a diameter less than the length of Manhattan, they pack more mass than that of our sun, wield the largest magnetic field of any known object—more ...
Astronomy
Jan 13, 2021
1
178
The shift to home-working triggered by the coronavirus pandemic looks set to endure long-term, making it vital to protect employees' rights and avoid blurred lines between on-the-clock hours and personal time, the United ...
Economics & Business
Jan 13, 2021
1
4
The descendants of regular wild-type bacteria can evolve to survive for a long time on metallic copper surfaces that would usually kill them within a few minutes. An international research team led by Martin Luther University ...
Cell & Microbiology
Jan 13, 2021
0
4
Special relativity is one of the most strongly validated theories humanity has ever devised. It is central to everything from space travel and GPS to our electrical power grid. Central to relativity is the fact that the speed ...
General Physics
Jan 11, 2021
24
37
Scientists sequencing virus samples from the first confirmed cases of COVID-19 in Scotland (and through the first wave) have found evidence of community transmission, driven by multiple introductions through international ...
Cell & Microbiology
Jan 08, 2021
1
149
Researchers from CAS Key Laboratory of Quantum Information of the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences have demonstrated on-demand storage of photonic qubits in an integrated ...
General Physics
Jan 08, 2021
0
307
Scientists around the world have noted that the Earth has been spinning on its axis faster lately—the fastest ever recorded. Several scientists have spoken to the press about the unusual phenomenon, with some pointing out ...
A new study in the Oxford Economic Papers finds that migration flows the last 500 years from high sunlight regions to low sunlight regions influence contemporary health outcomes in destination countries.
Evolution
Jan 07, 2021
1
926
Aquaculture is the world's fastest-growing animal-protein production sector, and the use of robots in many industries is growing quickly, as well. At North Carolina State University, researchers are finding ways to build ...
Plants & Animals
Jan 06, 2021
0
7
Time is a component of the measuring system used to sequence events, to compare the durations of events and the intervals between them, and to quantify the motions of objects. Time has been a major subject of religion, philosophy, and science, but defining it in a non-controversial manner applicable to all fields of study has consistently eluded the greatest scholars.
In physics as well as in other sciences, time is considered one of the few fundamental quantities. Time is used to define other quantities – such as velocity – and defining time in terms of such quantities would result in circularity of definition. An operational definition of time, wherein one says that observing a certain number of repetitions of one or another standard cyclical event (such as the passage of a free-swinging pendulum) constitutes one standard unit such as the second, is highly useful in the conduct of both advanced experiments and everyday affairs of life. The operational definition leaves aside the question whether there is something called time, apart from the counting activity just mentioned, that flows and that can be measured. Investigations of a single continuum called spacetime brings the nature of time into association with related questions into the nature of space, questions that have their roots in the works of early students of natural philosophy.
Among prominent philosophers, there are two distinct viewpoints on time. One view is that time is part of the fundamental structure of the universe, a dimension in which events occur in sequence. Time travel, in this view, becomes a possibility as other "times" persist like frames of a film strip, spread out across the time line. Sir Isaac Newton subscribed to this realist view, and hence it is sometimes referred to as Newtonian time. The opposing view is that time does not refer to any kind of "container" that events and objects "move through", nor to any entity that "flows", but that it is instead part of a fundamental intellectual structure (together with space and number) within which humans sequence and compare events. This second view, in the tradition of Gottfried Leibniz and Immanuel Kant, holds that time is neither an event nor a thing, and thus is not itself measurable nor can it be travelled.
Temporal measurement has occupied scientists and technologists, and was a prime motivation in navigation and astronomy. Periodic events and periodic motion have long served as standards for units of time. Examples include the apparent motion of the sun across the sky, the phases of the moon, the swing of a pendulum, and the beat of a heart. Currently, the international unit of time, the second, is defined in terms of radiation emitted by caesium atoms (see below). Time is also of significant social importance, having economic value ("time is money") as well as personal value, due to an awareness of the limited time in each day and in human life spans.
This text uses material from Wikipedia, licensed under CC BY-SA